Science.gov

Sample records for motricite digestive associees

  1. 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 ...

  2. Digestive diseases

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/007447.htm Digestive diseases To use the sharing features on this page, please enable JavaScript. Digestive diseases are disorders of the digestive tract, which ...

  3. Digestive System

    MedlinePlus

    ... is about 30 feet long. continue How Digestion Works Digestion Begins in the Mouth The process of ... a noncongenital condition. Esophagitis is usually caused by gastroesophageal reflux disease (GERD) , a condition in which the esophageal ...

  4. Elastase Digests

    PubMed Central

    Rietschel, Benjamin; Arrey, Tabiwang N.; Meyer, Bjoern; Bornemann, Sandra; Schuerken, Malte; Karas, Michael; Poetsch, Ansgar

    2009-01-01

    Despite many advances in membrane proteomics during the last decade the fundamental problem of accessing the transmembrane regions itself has only been addressed to some extent. The present study establishes a method for the nano-LC-based analysis of complex membrane proteomes on the basis of a methanolic porcine pancreatic elastase digest to increase transmembrane coverage. Halobacterium salinarium purple and Corynebacterium glutamicum membranes were successfully analyzed by using the new protocol. We demonstrated that elastase digests yield a large proportion of transmembrane peptides, facilitating membrane protein identification. The potential for characterization of a membrane protein through full sequence coverage using elastase is there but is restricted to the higher abundance protein components. Compatibility of the work flow with the two most common mass spectrometric ionization techniques, ESI and MALDI, was shown. Currently better results are obtained using ESI mainly because of the low response of MALDI for strictly neutral peptides. New findings concerning elastase specificity in complex protein mixtures reveal a new prospect beyond the application in shotgun experiments. Furthermore peptide mass fingerprinting with less specific enzymes might be done in the near future but requires an adaptation of current search algorithms to the new proteases. PMID:19116210

  5. 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. PMID:26799793

  6. Digestive Diseases Materials

    MedlinePlus

    ... NIDDK Health Information NIDDK Home NIDDK Image Library Digestive Disease, Nutrition, and Weight-control Materials Healthy eating, ... Materials Statistics Tip Sheets Catalog Home | Diabetes Materials | Digestive Diseases Materials | Kidney and Urologic Diseases Materials Online ...

  7. Digestive Diseases A-Z

    MedlinePlus

    ... Home Health Information Digestive Diseases English English Español Digestive Diseases The digestive system made up of the ... Upper GI Endoscopy Upper GI Series Virtual Colonoscopy Digestive Disease Topics Abdominal Adhesions Acid Reflux (GER & GERD) ...

  8. Membrane controlled anaerobic digestion

    NASA Astrophysics Data System (ADS)

    Omstead, D. R.

    In response to general shortages of energy, examination of the anaerboic digestion process as a potential source of a combustible, methane-rich fuel has intensified in recent years. It has been suggested that orgaic intermediates (such as fatty acids), produced during digestion, might also be recovered for use as chemical feedstocks. This investigation has been concerned with combining ultrafiltration separation techniques with anaerobic digestion for the development of a process in which the total production of acetic acid (the most valuable intermediate in anaerobic digestion) and methane are optimized. Enrichment cultures, able to utilize glucose as a sole carbon source, were adapted from sewage digesting cultures using conventional techniques. An ultrafiltration system was constructed and coupled to an anaerobic digester culture vessel which contained the glucose enrichment. The membrane controlled anaerobic digester appears to show promise as a means of producing high rates of both methane gas and acetic acid.

  9. (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.

  10. 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.

  11. 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...

  12. 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.

  13. 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.

  14. Effects of Aging on the Digestive System

    MedlinePlus

    ... Mail Facebook TwitterTitle Google+ LinkedIn 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 ...

  15. 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.

  16. Interracial Digest, Number 1.

    ERIC Educational Resources Information Center

    Council on Interracial Books for Children, Inc., New York, NY.

    This is a digest of articles which originally appeared in the bulletin, "Interracial Books for Children." Its purpose is to evaluate trade and textbooks with special concern for racist and sexist content and to suggest alternative materials for home and classroom. Included are the following articles: Doctor Dolittle--The Great White Father,…

  17. Carbohydrate digestion and absorption

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A variety of simple and complex carbohydrates are present in human diets. Food carbohydrates include the sugars, starches, and fibers found mainly in fruits, vegetables, grains, and milk products. Small amounts of digestible carbohydrates come from non-plant sources (e.g., trehalose in insects and...

  18. 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…

  19. Defining Giftedness. 1985 Digest.

    ERIC Educational Resources Information Center

    McClellan, Elizabeth

    The digest examines conceptions of giftedness. A brief historical review notes L. Terman's work and impetus for increasingly broadened definitions since the 1940's. The 1969 Marland Report is cited and its definition of giftedness is presented. Current response to that definition's inclusion of six achievement areas (general academic ability,…

  20. 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…

  1. Principal Mentoring. ERIC Digest.

    ERIC Educational Resources Information Center

    Malone, Robert J.

    To help new principals succeed, school districts are capitalizing on senior administrators' expertise by adding mentor programs to the practical training programs for beginning principals. This digest examines the nature of mentorships and discusses how they can prepare principals for the next stage of their careers. Although mentoring has existed…

  2. State Issues Digest, 2003.

    ERIC Educational Resources Information Center

    American Association of State Colleges and Universities, Washington, DC.

    This digest is designed to provide campus leaders with an up-to-date, "bird's eye" view of key issues affecting state colleges and universities. The American Association of State Colleges and Universities conducted is annual State Issues Survey of the Council of State Representatives in 2002 and received 44 responses from 61 college and university…

  3. Electronic Networking. ERIC Digest.

    ERIC Educational Resources Information Center

    Tucker, Susan

    This digest discusses several aspects of electronic networking, including network functions, implementation, and applications in education. Electronic networking is defined as including the four basic services of electronic mail (E-mail), electronic "bulletin boards," teleconferencing, and online databases, and an overview of these four functions…

  4. [Digestive endometriosis. Current concepts].

    PubMed

    Caligaris, P; Ducassou, M J; Masselot, R; Maurin, B; Cardon, J M; Bricot, R

    1982-12-01

    Endometriosis involving the digestive tract accounts for 1% of all cases of the disease. There is a marked predominance in the recto-sigmoid and terminal ileal loops. Symptomatology is dominated by disturbances in intestinal transit, sub-occlusion or acute obstruction, pain worsening at the time of menstruation and by a haemorrhagic rectal discharge again accompanying menstruation. Apart from classical aetiopathogenic theories such as grafting onto the digestive tract by tubal, lymph vessel or venous propagation, it would appear that prostaglandins and in particular a change in the (formula; see text) ratio may play a large role. Operative resection of localised stenosis combined with oophorectomy, if the latter is possible in view of the patient's age, or prolonged medical treatment with progestational agents or even better Danazol results in cure and avoids recurrences. PMID:6891703

  5. Refeeding biogas digester solids

    SciTech Connect

    Licht, L.A.

    1981-01-01

    Biosolid, the digester residue from a biogas plant, must be of economical use to ensure the financial feasibility of biogas facilities. This paper sumarizes work performed for a Department of Energy study in the Imperial Valley of California. Feeding trials show that biosolid can only be used as a small proportion of feed rations. Apart from bacterial debris, biosolid is composed larely of non-nutritive residues. 5 refs.

  6. 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

  7. 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.

  8. 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.

  9. Digest of Education Statistics, 2000.

    ERIC Educational Resources Information Center

    Snyder, Thomas D.; Hoffman, Charlene M.

    This edition of the "Digest of Education Statistics" is the 36th in a series that provides a compilation of statistical information covering the broad field of U.S. education from kindergarten through graduate school. The Digest includes data from many sources, both government and private, and draws heavily on work done by the National Center for…

  10. 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 accepting…

  11. Obscure digestive bleeding.

    PubMed

    Van Gossum, A

    2001-02-01

    Obscure digestive bleeding is defined as recurrent bleeding for which no definite source has been identified by routine endoscopic or barium studies. Mucosal vascular abnormality or 'angioectasia' is the most common course of obscure bleeding, especially in elderly patients. Small bowel tumours are more frequent in patients younger than 50 years. However, missed or underestimated upper and lower gastrointestinal lesions at the initial endoscopic investigation may be the source of a so-called obscure intestinal bleeding. The various radiological procedures, including enteroclysis, visceral angiography and CT scan as well as radioisotope bleeding scans have limitations in the case of obscure gastrointestinal bleeding. Recent developments in magnetic resonance imaging are promising. The different methods of enteroscopy have a similar diagnostic yield, reaching approximately 40-65%. Endoscopic cauterization of small bowel angioectasias seems to be efficacious but randomized trials are needed. Efficacy of hormonal therapy is very controversial. The extent of diagnostic and therapeutic strategies must be based on a number of factors including the patient's parameters, bleeding characteristics and also the result of previous work-up. PMID:11355906

  12. 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.

  13. 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

  14. 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.

  15. Your Digestive System and How It Works

    MedlinePlus

    ... at the junction of the esophagus and stomach, controls the passage of food and liquid between the esophagus and stomach. As ... different nutrients. The small intestine absorbs most digested food ... digestive process. [ Top ] Clinical Trials The National ...

  16. 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…

  17. Gas in the Digestive Tract

    MedlinePlus

    ... digestive tract when you swallow air and when bacteria in your large intestine break down certain undigested foods. ​​​​ Diagnosis of Gas Doctors may diagnose the causes of gas with a medical history and physical exam. If your doctor suspects you ...

  18. 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…

  19. What Is Dyslexia: 1984 Digest.

    ERIC Educational Resources Information Center

    Harrie, Roger P.; Weller, Carol

    The digest focuses on the nature of dyslexia and its characteristics. An initial section notes the variations in definitions as a function of the discipline. Diagnosis of dyslexia is said to isolate the specific difficulties associated with the problem and to suggest appropriate educational intervention. Typical characteristics of dyslexia are…

  20. Inducting School Leaders. ERIC Digest.

    ERIC Educational Resources Information Center

    Lashway, Larry

    Beginning principals are often overwhelmed by their job. Traditionally, they have been left to fend for themselves. For this reason, schools and districts have been implementing formal induction programs to help the principals during their first year on the job. This digest examines the challenges faced by new administrators and the steps that…

  1. 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…

  2. 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…

  3. FEU Technology Digest No. 3.

    ERIC Educational Resources Information Center

    Further Education Unit, London (England).

    This digest contains four articles about technology and education in Britain. "The Development of an 'Additional Skills' Training Programme" (Peter Riley) details the organization and progress of a collaborative effort between Blackpool Processing Company and Flyde College's Additional Skills training program, a solution to achieving the flexible…

  4. Videodiscs in Education. ERIC Digest.

    ERIC Educational Resources Information Center

    McLean, Lois

    This digest discusses the nature of interactive videodiscs and their educational applications, provides information about educational uses of videodisc technology, and presents lists of videodisc-related organizations, books, and periodicals. A general description of a reflective optical laser videodisc is presented, as well as the equipment…

  5. Identifying Potential Dropouts. ERIC Digest.

    ERIC Educational Resources Information Center

    Gaustad, Joan

    An overview of issues and problems in identifying and predicting dropouts is presented in this Digest. The topics discussed are as follows: factors associated with dropping out; defining and calculating dropouts; problems in prediction; the usefulness of current prediction models; and suggestions for improving prediction. The recommendation is…

  6. 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…

  7. 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…

  8. 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…

  9. Prekindergarten Teacher Licensure. ERIC Digest.

    ERIC Educational Resources Information Center

    Stein, Sheryl E.

    This digest examines prekindergarten teacher licensure, which enables states to ensure a level of specialized knowledge and experience among early childhood professionals. A recent movement toward specialization has led to more states offering early childhood education licenses (which is beneficial since the best predictor of appropriate teacher…

  10. 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…

  11. Coaching for Tests. ERIC Digest.

    ERIC Educational Resources Information Center

    Wildemuth, Barbara

    The term "coaching" applies to a variety of types of test preparation programs which vary in length, instructional method, and content. Most research on the effectiveness of coaching has examined the Scholastic Aptitude Test (SAT), a measure of academic abilities used to predict college performance. This ERIC Digest reviews studies of coaching for…

  12. Improving Principal Evaluation. ERIC Digest.

    ERIC Educational Resources Information Center

    Lashway, Larry

    In recent years, the role of the principal has become more critical in the success of schools. School improvement is often tied to principal performance, yet the practice of evaluating principal performance leaves a lot to be desired, according to some educators. This ERIC Digest reviews current principal evaluation practices and describes some…

  13. 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...

  14. Modifying crops to increase cell wall digestibility.

    PubMed

    Jung, Hans-Joachim G; Samac, Deborah A; Sarath, Gautam

    2012-04-01

    Improving digestibility of roughage cell walls will improve ruminant animal performance and reduce loss of nutrients to the environment. The main digestibility impediment for dicotyledonous plants is highly lignified secondary cell walls, notably in stem secondary xylem, which become almost non-digestible. Digestibility of grasses is slowed severely by lignification of most tissues, but these cell walls remain largely digestible. Cell wall lignification creates an access barrier to potentially digestible wall material by rumen bacteria if cells have not been physically ruptured. Traditional breeding has focused on increasing total dry matter digestibility rather than cell wall digestibility, which has resulted in minimal reductions in cell wall lignification. Brown midrib mutants in some annual grasses exhibit small reductions in lignin concentration and improved cell wall digestibility. Similarly, transgenic approaches down-regulating genes in monolignol synthesis have produced plants with reduced lignin content and improved cell wall digestibility. While major reductions in lignin concentration have been associated with poor plant fitness, smaller reductions in lignin provided measurable improvements in digestibility without significantly impacting agronomic fitness. Additional targets for genetic modification to enhance digestibility and improve roughages for use as biofuel feedstocks are discussed; including manipulating cell wall polysaccharide composition, novel lignin structures, reduced lignin/polysaccharide cross-linking, smaller lignin polymers, enhanced development of non-lignified tissues, and targeting specific cell types. Greater tissue specificity of transgene expression will be needed to maximize benefits while avoiding negative impacts on plant fitness.cauliflower mosiac virus (CaMV) 35S promoter. PMID:22325867

  15. PERFORMANCE EVALUATION OF THE DUAL DIGESTION SYSTEM

    EPA Science Inventory

    The dual digestion system (DDS) was developed to provide stabilized, pathogen free sludge. DDS consists of a 1-day detention time, pure-oxygen, covered aerobic digester (Step I) followed by an 8-day detention time anaerobic reactor. The temperature in the Step I digester is contr...

  16. 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 ...

  17. Communication Strategies for Employment Interviews. ERIC Digest.

    ERIC Educational Resources Information Center

    Aiex, Nola Kortner

    Intended to help prepare individuals for job seeking, this digest suggests some resources to consult to help improve basic communication skills needed for the interview process. The digest reviews research on teaching interview skills in the classroom, discussing role playing, videotapes, and techniques workshops. The digest also lists practical…

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

    PubMed Central

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

    2015-01-01

    Scope Resistance of proteins to gastrointestinal digestion may play a role in determining immune‐mediated adverse reactions to foods. However, digestion studies have largely been restricted to purified proteins and the impact of food processing and food matrices on protein digestibility is poorly understood. Methods and results Digestibility of a total gliadin fraction (TGF), flour (cv Hereward), and bread was assessed using in vitro batch digestion with simulated oral, gastric, and duodenal phases. Protein digestion was monitored by SDS‐PAGE and immunoblotting using monoclonal antibodies specific for celiac‐toxic sequences (QQSF, QPFP) and starch digestion by measuring undigested starch. Whereas the TGF was rapidly digested during the gastric phase the gluten proteins in bread were virtually undigested and digested rapidly during the duodenal phase only if amylase was included. Duodenal starch digestion was also slower in the absence of duodenal proteases. Conclusion The baking process reduces the digestibility of wheat gluten proteins, including those containing sequences active in celiac disease. Starch digestion affects the extent of protein digestion, probably because of gluten‐starch complex formation during baking. Digestion studies using purified protein fractions alone are therefore not predictive of digestion in complex food matrices. PMID:26202208

  19. The digestibility of waste activated sludges.

    PubMed

    Park, Chul; Abu-Orf, Mohammad M; Novak, John T

    2006-01-01

    Laboratory digestion studies using waste activated sludges (WAS) were conducted to compare the digestion performance between anaerobic and aerobic processes. Nine samples of WAS from seven wastewater treatment plants were collected and batch-digested under both anaerobic and aerobic conditions for 30 days at 25 degrees C. The cation content of wastewater (both floc and solution phases) and solution biopolymer (protein and polysaccharide) was measured before and after digestion and compared with volatile solids destruction data. The study revealed that each digestion process was associated with a distinct biopolymer fraction, which accounted for differences in volatile solids reduction under anaerobic and aerobic conditions. The anaerobic digestion data showed strong correlations between soluble protein generation, ammonium production, percent volatile solids reduction, and floc iron (Fe). These data suggest that the amount of volatile solids destroyed by anaerobic digestion depends on the Fe content of floc. In aerobic digestion, polysaccharide accumulated in solution along with calcium and magnesium. For aerobic digestion, correlations between divalent cation release and the production of inorganic nitrogen were found. This implies that divalent cation-bound biopolymer, thought to be lectin-like protein, was the primary organic fraction degraded under aerobic conditions. The results of the study show that the cation content in wastewater is an important indicator of the material that will digest under anaerobic or aerobic conditions and that some of the volatile solids will digest only under either anaerobic or aerobic conditions. PMID:16553167

  20. [Digestive surgery in the elderly].

    PubMed

    Duron, J J; Duron, E; Maneglia, R

    2005-01-01

    The dramatic increase in digestive surgery among patients of advanced age is the logical consequence of the aging population demographics in developed countries. Surgery in the aged is not fundamentally different, but it demands precise and tailored assessment and management of surgical indications and surgical and anesthetic techniques. Advanced age is not a contraindication to even major digestive surgery, but every effort must be made to avoid urgent operations by attention to pre-existing symptoms which are all-too-often neglected in the aged. Intensive care may help to shorten the hospital stay which should ideally occupy only a minor portion of the numbered days of the patient (whose life expectancy may be significantly longer than one may intuitively foresee). PMID:16142077

  1. 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.

  2. Anaerobic digestion of cellulosic wastes

    SciTech Connect

    Donaldson, T.L.; Lee, D.D.

    1984-01-01

    Anaerobic digestion is a potentially attractive technology for volume reduction of cellulosic wastes. A substantial fraction of the waste is converted to off-gas and a relatively small volume of biologically stabilized sludge is produced. Process development work is underway using a 75-L digester to verify rates and conversions obtained at the bench scale, to develop start-up and operating procedures, and to generate effluent for characterization and disposal studies. Three runs using batch and batch-fed conditions have been made lasting 36, 90, and over 200 days. Solids solubilization and gas production rates and total solids destruction have met or exceeded the target values of 0.6 g cellulose per L of reactor per day, 0.5 L off-gas per L of reactor per day, and 80% destruction of solids, respectively. Successful start-up procedures have been developed, and preliminary effluent characterization and disposal studies have been done. A simple dynamic process model has been constructed to aid in further process development and for use in process monitoring and control of a large-scale digester. 7 references, 5 figures, 1 table.

  3. Anaerobic digestion of cellulosic wastes

    SciTech Connect

    Lee, D.D.; Donaldson, T.L.

    1985-01-01

    Anaerobic digestion is a potentially attractive technology for volume reduction of low-level radioactive cellulosic wastes. A substantial fraction of the waste is converted to off-gas and a relatively small volume of biologically stabilized sludge is produced. Process development work has been completed using a 75-L digester to verify rates and conversions obtained at the bench scale. Start-up and operating procedures have been developed, and effluent was generated for characterization and disposal studies. Three runs using batch and fed-batch conditions were made lasting 36, 90, and 423 d. Solids solubilization rates and gas production rates averaged approximately 1.8 g cellulose per L of reactor per d and 1.2 L of off-gas per L reactor per d. Greater than 80% destruction of the volatile suspended solids was obtained. A simple dynamic process model was constructed to aid in process design and for use in process monitoring and control of a large-scale digester.

  4. A rapid DNA digestion system.

    PubMed

    Fu, Lung-Ming; Lin, Che-Hsin

    2007-04-01

    This paper presents a novel microfluidic DNA digestion system incorporating a high performance micro-mixer. Through the appropriate control of fixed and periodic switching DC electric fields, electrokinetic forces are established to mix the DNA and restriction enzyme samples and to drive them through the reaction column of the device. The experimental and numerical results show that a mixing performance of 98% can be achieved within a mixing channel of length 1.6 mm when a 150 V/cm driving voltage and a 5 Hz switching frequency are applied. The relationship between the mixing performance, switching frequency, and main applied electric field is derived. It is found that the optimal switching frequency depends upon the magnitude of the main applied electric field. The successful digestion of lambda-DNA using Eco RI restriction enzyme is demonstrated. The DNA-enzyme reaction is completed within 15 min in the proposed microfluidic system, compared to 50 min in a conventional large-scale system. Hence, the current device provides a valuable tool for rapid lambda-DNA digestion, while its mixer system delivers a simple yet effective solution for mixing problems in the micro-total-analysis-systems field. PMID:17195107

  5. Biochar from anaerobically digested sugarcane bagasse.

    PubMed

    Inyang, Mandu; Gao, Bin; Pullammanappallil, Pratap; Ding, Wenchuan; Zimmerman, Andrew R

    2010-11-01

    This study was designed to investigate the effect of anaerobic digestion on biochar produced from sugarcane bagasse. Sugarcane bagasse was anaerobically digested to produce methane. The digested residue and fresh bagasse was pyrolyzed separately into biochar at 600 degrees C in nitrogen environment. The digested bagasse biochar (DBC) and undigested bagasse biochar (BC) were characterized to determine their physicochemical properties. Although biochar was produced from the digested residue (18% by weight) and the raw bagasse (23%) at a similar rate, there were many physiochemical differences between them. Compared to BC, DBC had higher pH, surface area, cation exchange capacity (CEC), anion exchange capacity (AEC), hydrophobicity and more negative surface charge, all properties that are generally desirable for soil amelioration, contaminant remediation or wastewater treatment. Thus, these results suggest that the pyrolysis of anaerobic digestion residues to produce biochar may be an economically and environmentally beneficial use of agricultural wastes. PMID:20634061

  6. 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.

  7. 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…

  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. PMID:27191559

  9. Auditory Processing Disorders: An Overview. ERIC Digest.

    ERIC Educational Resources Information Center

    Ciocci, Sandra R.

    This digest presents an overview of children with auditory processing disorders (APDs), children who can typically hear information but have difficulty attending to, storing, locating, retrieving, and/or clarifying that information to make it useful for academic and social purposes. The digest begins by describing central auditory processing and…

  10. Modifying crops to increase cell wall digestibility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improving digestibility of roughage cell walls will improve ruminant animal performance and reduce loss of nutrients to the environment. The main digestibility impediment for dicotyledonous plants are highly lignified secondary cell walls, notably in stem secondary xylem, which become almost non-dig...

  11. 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 applying…

  12. State Standards, Assessments and Instruction. ERIC Digest.

    ERIC Educational Resources Information Center

    Tienken, Christopher; Wilson, Michael

    This digest describes a program used by two New Jersey educators to help teachers improve instruction through a deeper understanding of state standards and test specifications. Understanding how standards-based tests are constructed is the first step in being able to use them to guide and improve instruction. This digest recommends, as the route…

  13. TECHNOLOGY EVALUATION OF THE DUAL DIGESTION SYSTEM

    EPA Science Inventory

    Full-scale performance and costs of an innovative sludge stabilization process were evaluated at the three plants. The DDS incorporates a 1-day-detention-time, pure oxygen aerobic digester followed in series by an 8-day-detention-time anaerobic digester. Heat of biological oxidat...

  14. Functional Utrastructure of Genlisea (Lentibulariaceae) Digestive Hairs

    PubMed Central

    Płachno, Bartosz Jan; Kozieradzka-Kiszkurno, Małgorzata; Świątek, Piotr

    2007-01-01

    Background and Aims Digestive structures of carnivorous plants produce external digestive enzymes, and play the main role in absorption. In Lentibulariaceae, the ultrastructure of digestive hairs has been examined in some detail in Pinguicula and Utricularia, but the sessile digestive hairs of Genlisea have received very little attention so far. The aim of this study was to fill this gap by expanding their morphological, anatomical and histochemical characterization. Methods Several imaging techniques were used, including light, confocal and electron microscopy, to reveal the structure and function of the secretory hairs of Genlisea traps. This report demonstrates the application of cryo-SEM for fast imaging of whole, physically fixed plant secretory structures. Key Results and Conclusion The concentration of digestive hairs along vascular bundles in subgenus Genlisea is a primitive feature, indicating its basal position within the genus. Digestive hairs of Genlisea consist of three compartments with different ultrastructure and function. In subgenus Tayloria the terminal hair cells are transfer cells, but not in species of subgenus Genlisea. A digestive pool of viscous fluid occurs in Genlisea traps. In spite of their similar architecture, the digestive-absorptive hairs of Lentibulariaceae feature differences in morphology and ultrastructure. PMID:17550910

  15. Cyberspace Class: Rewards and Punishments. ERIC Digest.

    ERIC Educational Resources Information Center

    Shoemake, Barbara R.

    This Digest details how one professor of public relations has developed and put into practice a class in "cyberspace." The Digest first provides background on online communication techniques and the explosion of online teaching at the university level, and then tells how a professor, with the help of a summer grant from her university, developed…

  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. 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…

  19. Motivating Low Performing Adolescent Readers. ERIC Digest.

    ERIC Educational Resources Information Center

    Collins, Norma Decker

    This Digest focuses on motivating the low performing adolescent in a remedial reading or subject area classroom--the idea is that students who are disengaged from their own learning processes are not likely to perform well in school. The Digest points out that such adolescents are often caught in a cycle of failure and that secondary teachers must…

  20. Discourses of Disability in the "Digest."

    ERIC Educational Resources Information Center

    Barton, Ellen

    2001-01-01

    Presents an account of the discourse of disability in the "Reader's Digest" during its first 30 years (1922-1952). Concludes that the construction of disability in the "Digest" raises important questions that should enter the field of disability studies. (PM)

  1. 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,…

  2. Severe Disabilities. ERIC Digest #311. Revised.

    ERIC Educational Resources Information Center

    Council for Exceptional Children, Reston, VA.

    This digest defines the term "severe disabilities"; lists some typical behavioral characteristics of individuals with severe disabilities, such as self-mutilation and lack of self-care skills; and outlines the educational implications of severe disabilities. The digest stresses the need for a multidisciplinary approach to education; the need for a…

  3. 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…

  4. Water soluble carbohydrates affects dry matter digestibility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The low energy concentration of forages often limits animal performance. This limitation in performance can be mitigated by either increasing daily dry matter intake (DMI) or digestibility, or both, resulting in greater daily digestible DMI. The diurnal fluctuation in forage composition, especially ...

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

    PubMed

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

    2010-04-28

    This paper describes an in vitro study that tests the proposition that actinidin from green kiwifruit influences the digestion of proteins in the small intestine. Different food proteins, from sources including soy, meat, milk, and cereals, were incubated in the presence or absence of green kiwifruit extract (containing actinidin) using a two-stage in vitro digestion system consisting of an incubation with pepsin at stomach pH (simulating gastric digestion) and then with added pancreatin at small intestinal pH, simulating upper tract digestion in humans. The digests from the small intestinal stage (following the gastric digestion phase) were subjected to gel electrophoresis (SDS-PAGE) to assess loss of intact protein and development of large peptides during the in vitro simulated digestion. Kiwifruit extract influenced the digestion patterns of all of the proteins to various extents. For some proteins, actinidin had little impact on digestion. However, for other proteins, the presence of kiwifruit extract resulted in a substantially greater loss of intact protein and different peptide patterns from those seen after digestion with pepsin and pancreatin alone. In particular, enhanced digestion of whey protein isolate, zein, gluten, and gliadin was observed. In addition, reverse-phase HPLC (RP-HPLC) analysis showed that a 2.5 h incubation of sodium caseinate with kiwifruit extract alone resulted in approximately 45% loss of intact protein. PMID:20232891

  6. 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.

  7. 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. PMID:27054731

  8. 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

  9. 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.

  10. High rate manure supernatant digestion.

    PubMed

    Bergland, Wenche Hennie; Dinamarca, Carlos; Toradzadegan, Mehrdad; Nordgård, Anna Synnøve Røstad; Bakke, Ingrid; Bakke, Rune

    2015-06-01

    The study shows that high rate anaerobic digestion may be an efficient way to obtain sustainable energy recovery from slurries such as pig manure. High process capacity and robustness to 5% daily load increases are observed in the 370 mL sludge bed AD reactors investigated. The supernatant from partly settled, stored pig manure was fed at rates giving hydraulic retention times, HRT, gradually decreased from 42 to 1.7 h imposing a maximum organic load of 400 g COD L(-1) reactor d(-1). The reactors reached a biogas production rate of 97 g COD L(-1) reactor d(-1) at the highest load at which process stress signs were apparent. The yield was ∼0.47 g COD methane g(-1) CODT feed at HRT above 17 h, gradually decreasing to 0.24 at the lowest HRT (0.166 NL CH4 g(-1) CODT feed decreasing to 0.086). Reactor pH was innately stable at 8.0 ± 0.1 at all HRTs with alkalinity between 9 and 11 g L(-1). The first stress symptom occurred as reduced methane yield when HRT dropped below 17 h. When HRT dropped below 4 h the propionate removal stopped. The yield from acetate removal was constant at 0.17 g COD acetate removed per g CODT substrate. This robust methanogenesis implies that pig manure supernatant, and probably other similar slurries, can be digested for methane production in compact and effective sludge bed reactors. Denaturing gradient gel electrophoresis (DGGE) analysis indicated a relatively fast adaptation of the microbial communities to manure and implies that non-adapted granular sludge can be used to start such sludge bed bioreactors. PMID:25776915

  11. 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. PMID:26903302

  12. 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.

  13. Inhibition of anaerobic digestion process: a review.

    PubMed

    Chen, Ye; Cheng, Jay J; Creamer, Kurt S

    2008-07-01

    Anaerobic digestion is an attractive waste treatment practice in which both pollution control and energy recovery can be achieved. Many agricultural and industrial wastes are ideal candidates for anaerobic digestion because they contain high levels of easily biodegradable materials. Problems such as low methane yield and process instability are often encountered in anaerobic digestion, preventing this technique from being widely applied. A wide variety of inhibitory substances are the primary cause of anaerobic digester upset or failure since they are present in substantial concentrations in wastes. Considerable research efforts have been made to identify the mechanism and the controlling factors of inhibition. This review provides a detailed summary of the research conducted on the inhibition of anaerobic processes. The inhibitors commonly present in anaerobic digesters include ammonia, sulfide, light metal ions, heavy metals, and organics. Due to the difference in anaerobic inocula, waste composition, and experimental methods and conditions, literature results on inhibition caused by specific toxicants vary widely. Co-digestion with other waste, adaptation of microorganisms to inhibitory substances, and incorporation of methods to remove or counteract toxicants before anaerobic digestion can significantly improve the waste treatment efficiency. PMID:17399981

  14. 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.

  15. 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.

  16. 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. PMID:23871080

  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. PMID:25457225

  18. Northern New England's Dairy Manure digesters

    SciTech Connect

    Gilman, F.E.; Bennett, S.

    1985-01-01

    Dairy Manure digesters are complimentary to systematized manure handling providing unique opportunities for by-product use and pollution control. Separated solids used for bedding are a valued by-product in addition to cash income from electric power sold.

  19. Energy and environment legislative digest 2008

    SciTech Connect

    2008-08-15

    This Digest (published every year) is a compilation of energy and environmental legislation enacted by the Southern States Energy Board's 18 member states and territories during the 2008 legislative session.

  20. 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.

  1. Learning Disabilities. ERIC Digest #407. Revised.

    ERIC Educational Resources Information Center

    ERIC Clearinghouse on Handicapped and Gifted Children, Reston, VA.

    This digest defines learning disabilities, cites their prevalence, describes typical characteristics of learning-disabled students, outlines educational implications of learning disabilities, and lists several printed and organizational resources for further information. (JDD)

  2. Stromal Fibroblasts in Digestive Cancer

    PubMed Central

    Worthley, Daniel L.; Giraud, Andrew S.

    2010-01-01

    The normal gastrointestinal stroma consists of extra-cellular matrix and a community of stromal cells including fibroblasts, myofibroblasts, smooth muscle cells, pericytes, endothelium and inflammatory cells. α-smooth muscle actin (α-SMA) positive stromal fibroblasts, often referred to as myofibroblasts or activated fibroblasts, are critical in the development of digestive cancer and help to create an environment that is permissive of tumor growth, angiogenesis and invasion. This review focusses on the contribution of activated fibroblasts in carcinogenesis and where possible directly applies this to, and draws on examples from, gastrointestinal cancer. In particular, the review expands on the definition, types and origins of activated fibroblasts. It examines the molecular biology of stromal fibroblasts and their contribution to the peritumoral microenvironment and concludes by exploring some of the potential clinical applications of this exciting branch of cancer research. Understanding the origin and biology of activated fibroblasts will help in the development of an integrated epithelial-stromal sequence to cancer that will ultimately inform cancer pathogenesis, natural history and future therapeutics. PMID:21209778

  3. Pressurized wet digestion in open vessels.

    PubMed

    Maichin, B; Zischka, M; Knapp, G

    2003-07-01

    The High Pressure Asher (HPA-S) was adapted with a Teflon liner for pressurized wet digestion in open vessels. The autoclave was partly filled with water containing 5% (vol/vol) hydrogen peroxide. The digestion vessels dipped partly into the water or were arranged on top of the water by means of a special rack made of titanium or PTFE-coated stainless steel. The HPA-S was closed and pressurized with nitrogen up to 100 bars. The maximum digestion temperature was 250 degrees C for PFA vessels and 270 degrees C for quartz vessels. Digestion vessels made of quartz or PFA-Teflon with volumes between 1.5 mL (auto sampler cups) and 50 mL were tested. The maximum sample amount for quartz vessels was 0.5-1.5 g and for PFA vessels 0.2-0.5 g, depending on the material. Higher sample intake may lead to fast reactions with losses of digestion solution. The samples were digested with 5 mL HNO(3) or with 2 mL HNO(3)+6 mL H(2)O+2 mL H(2)O(2). The total digestion time was 90-120 min and 30 min for cooling down to room temperature. Auto sampler cups made of PFA were used as digestion vessels for GFAAS. Sample material (50 mg) was digested with 0.2 mL HNO(3)+0.5 mL H(2)O+0.2 mL H(2)O(2). The analytical data of nine certified reference materials are also within the confidential intervals for volatile elements like mercury, selenium and arsenic. No cross contamination between the digestion vessels could be observed. Due to the high gas pressure, the diffusion rate of volatile species is low and losses of elements by volatilisation could be observed only with diluted nitric acid and vessels with large cross section. In addition, cocoa, walnuts, nicotinic acid, pumpkin seeds, lubrication oil, straw, polyethylene and coal were digested and the TOC values measured. The residual carbon content came to 0.2-10% depending on the sample matrix and amount. PMID:12802569

  4. 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.

  5. 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

  6. 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. PMID:14979566

  7. Partial stream digestion of residual municipal solid waste.

    PubMed

    De Baere, L

    2008-01-01

    Anaerobic digestion of residual municipal solid waste (MSW) has become more important than the digestion of source separated biowaste. More than 52% of the capacity available in Europe was designed for digestion of residual municipal waste by the end of 2006, while this was only 13% in 1998. Partial digestion of residual waste organics, by which only a part of the organics is digested, has been implemented to reduce the need for dewatering and subsequent wastewater treatment. The digestate coming from part of the organics is immediately mixed with the non-digested organic fraction. This organic fraction is drier and still contains a lot of energy which can be used to dry the digestate during the aerobic composting of the mixture of digested and undigested organics. Such a MBT-plant has been operating for over a year whereby 2/3 of the organics (including sludge cake) are digested (25,000 t/year) and mixed after digestion with the remaining 1/3 of the organics. Biogas production averages 125.7 Nm2 per ton fed and contained 56.2% of methane. The mixture of digestate and non-digested organics is aerated in tunnels during 4 to 6 weeks. The stabilized end product is landfilled, meeting the stringent German standards for inert landfills. By using a dry fermentation able to produce a digestate at 35% solids, there is no need for dewatering the digestate so that no wastewater is produced. PMID:18441435

  8. 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…

  9. 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. PMID:24760222

  10. Carnivorous mammals: nutrient digestibility and energy evaluation.

    PubMed

    Clauss, Marcus; Kleffner, Helen; Kienzle, Ellen

    2010-01-01

    Estimating the energy content is the first step in diet formulation, as it determines the amount of food eaten and hence the concentration of nutrients required to meet the animal's requirements. Additionally, being able to estimate the energy content of a diet empirically known to maintain body condition in an animal will facilitate an estimation of maintenance energy requirements. We collated data on nutrient composition of diets fed to captive wild canids, felids, hyenids, mustelids, pinnipeds, and ursids and the digestibility coefficients from the literature (45 species, 74 publications) to test whether differences in protein and fat digestibility could be detected between species groups, and whether approaches suggested for the estimation of dietary metabolizable energy (ME) content in domestic carnivores (NRC [2006] Nutrient requirements of dogs and cats. Washington, DC: National Academy Press.) can be applied to wild carnivores as well. Regressions of digestible protein or fat content vs. the crude protein (CP) or fat content indicated no relevant differences in the digestive physiology between the carnivore groups. For diets based on raw meat, fish, or whole prey, applying the calculation of ME using "Atwater factors" (16.7  kJ/g CP; 16.7  kJ/g nitrogen-free extracts; 37.7  kJ/g crude fat) provided estimates that compared well to experimental results. This study suggests that ME estimation in such diets is feasible without additional digestion trials. For comparative nutrition research, the study implicates that highly digestible diets typically fed in zoos offer little potential to elucidate differences between species or carnivore groups, but research on diets with higher proportions of difficult-to-digest components (fiber, connective tissues) is lacking. PMID:20073050

  11. 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. PMID:27396682

  12. [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

  13. Digestive system damage caused by substance abuse.

    PubMed

    Dimitrijević, I; Kalezić, N; Ristić, J; Bojović, O; Dimitrijević, N

    2008-01-01

    Substance abuse and addiction represent a worldwide problem and cause a number of family, social and health problems. Digestive system damage caused by substance intake is an increasing problem amoung drug addicts. Many studies show that substances can cause cancer of all parts of the digestive system. Alcohol consumption was significantly associated with colon and rectal cancer. For rectal cancer, the risk was increased in association with drinking of alcoholic beverages, specialy for beer consumption. Sinthetic drugs such as ecstasy may lead also to digestive and hepatic damage, as well as vascular complications of the stomach. Many studies show the existance of supstance associated enterocolitis as well as ishemic colitis. Diagnosis of ishemic colitis is based on the presence of rectal bleeding, abdominal pain, a history of substance use, supportive endoscopic and histopathologic findings, and the absence of other etiologic mechanisms of ischemic colitis. Great damage to the digestive system is also produced by smuggling narcotics packed into small pages that are afterwards been swallowed or implemented on other sorts of ways inside the smugglers natural body spaces as the rectum or vagina. In the paper authors reviewed literature conserning digestive system damage caused by substance abuse and drug smuggling. PMID:19069706

  14. Digestive disease resources on the Internet.

    PubMed

    Gumber, S C; O'Doherty, J E

    1999-08-01

    The aim of this study is to help digestive disease professionals fully utilize the resources available on the Internet for patient care, education, and research. The following search resources were employed to locate websites: general search engines--Lycos, Metacrawler, Webcrawler, and Yahoo!; medical search engines--HealthWeb, MedMatrix, MedWeb, and MedWebPlus; website links; and publications. The inclusion of web sites was based on their content. Each site was evaluated with respect to its authorship, attribution, currency, and disclosure. All digestive disease professional organizations and academic centers that met the above criteria were included. Only nutrition sites with relevance to digestive diseases were included. A variety of very useful web sites related to digestive diseases exist on the Internet, and their numbers are growing. Many of these sites have valuable information that can be used to improve patient care, promote medical education, and facilitate research. Digestive disease professionals should adopt the Internet and address the many issues raised by this technology. PMID:10445523

  15. 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. PMID:24695892

  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. The digestive tract of Drosophila melanogaster.

    PubMed

    Lemaitre, Bruno; Miguel-Aliaga, Irene

    2013-01-01

    The digestive tract plays a central role in the digestion and absorption of nutrients. Far from being a passive tube, it provides the first line of defense against pathogens and maintains energy homeostasis by exchanging neuronal and endocrine signals with other organs. Historically neglected, the gut of the fruit fly Drosophila melanogaster has recently come to the forefront of Drosophila research. Areas as diverse as stem cell biology, neurobiology, metabolism, and immunity are benefitting from the ability to study the genetics of development, growth regulation, and physiology in the same organ. In this review, we summarize our knowledge of the Drosophila digestive tract, with an emphasis on the adult midgut and its functional underpinnings. PMID:24016187

  18. Sophisticated digestive systems in early arthropods.

    PubMed

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

    2014-01-01

    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. PMID:24785191

  19. CFD simulation of mixing in anaerobic digesters.

    PubMed

    Terashima, Mitsuharu; Goel, Rajeev; Komatsu, Kazuya; Yasui, Hidenari; Takahashi, Hiroshi; Li, Y Y; Noike, Tatsuya

    2009-04-01

    A three-dimensional CFD model incorporating the rheological properties of sludge was developed and applied to quantify mixing in a full-scale anaerobic digester. The results of the model were found to be in good agreement with experimental tracer response curve. In order to predict the dynamics of mixing, a new parameter, UI (uniformity index) was defined. The visual patterns of tracer mixing in simulation were well reflected in the dynamic variation in the value of UI. The developed model and methods were applied to determine the required time for complete mixing in a full-scale digester at different solid concentrations. This information on mixing time is considered to be useful in optimizing the feeding cycles for better digester performance. PMID:19081247

  20. Fiber digestibility in royal antelope (Neotragus pygmaeus).

    PubMed

    Schmidt, Debra A; Schlegel, Michael L; Galyean, Michael L

    2014-12-01

    Royal antelope (Neotragus pygmaeus) are among the smallest ungulate species and are browsing ruminants. To date, their capacities for fiber fermentation and nutrient digestion have not been quantified. This study compared apparent digestibilities of a typical high-fiber herbivore pellet (ADF 25) and a low-starch, high-fiber diet (WHP) in royal antelope in a crossover design (seven subjects in the first period and four in the second). Animals on ADF 25 pellets had greater intake concentrations (P < 0.05) of dry matter, crude protein, lignin, and crude fat; however, animals fed the WHP diets had greater (P < 0.05) apparent digestibility of dry matter, acid detergent fiber, neutral detergent fiber, and crude fat. Identifying the capacity to which these smaller ruminants can degrade fiber will help to establish more appropriate feeding guidelines for small, browsing ruminants in captivity. PMID:25632658

  1. 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.

  2. 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. PMID:27155428

  3. Enhancing post aerobic digestion of full-scale anaerobically digested sludge using free nitrous acid pretreatment.

    PubMed

    Wang, Qilin; Zhou, Xu; Peng, Lai; Wang, Dongbo; Xie, Guo-Jun; Yuan, Zhiguo

    2016-05-01

    Post aerobic digestion of anaerobically digested sludge (ADS) has been extensively applied to the wastewater treatment plants to enhance sludge reduction. However, the degradation of ADS in the post aerobic digester itself is still limited. In this work, an innovative free nitrous acid (HNO2 or FNA)-based pretreatment approach is proposed to improve full-scale ADS degradation in post aerobic digester. The post aerobic digestion was conducted by using an activated sludge to aerobically digest ADS for 4 days. Degradations of the FNA-treated (treated at 1.0 and 2.0 mg N/L for 24 h) and untreated ADSs were then determined and compared. The ADS was degraded by 26% and 32%, respectively, in the 4-day post aerobic digestion period while being pretreated at 1.0 and 2.0 mg HNO2-N/L. In comparison, only 20% of the untreated ADS was degraded. Economic analysis demonstrated that the implementation of FNA pretreatment can be economically favourable or not depending on the sludge transport and disposal cost. PMID:26901471

  4. 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

  5. Thermophilic anaerobic digestion of high strength wastewaters

    SciTech Connect

    Wiegant, W.M.; Claassen, J.A.; Lettinga, G.

    1985-09-01

    Investigations on the thermophilic anaerobic treatment of high-strength wastewaters (14-65 kg COD/mT) are presented. Vinasse, the wastewater of alcohol distilleries, was used as an example of such wastewaters. Semicontinuously fed digestion experiments at high retention times revealed that the effluent quality of digestion at 55C is comparable with that at 30C at similar loading rates. The amount of methane formed per kilogram of vinasse drops almost linearly with increasing vinasse concentrations. The treatment of vinasse was also investigated using upflow anaerobic sludge blanket (UASB) reactors.

  6. 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

  7. Thermophilic anaerobic digestion of industrial orange waste.

    PubMed

    Kaparaju, P L N; Rintala, J A

    2006-06-01

    Thermophilic anaerobic digestion of industrial orange waste (pulp and peel) with subsequent aerobic post-treatment of the digestate was evaluated. Methane production potential was first determined in batch assays and the effects of operational parameters such as hydraulic retention times (HRT) and organic loading rates (OLR) on process performance were studied through semi-continuous digestion. In batch assays, methane production potential of about 0.49 m(3) kg(-1) volatile solids (VS)(added waste) was achieved. In semi-continuous digestion, loading at 2.8 kgVS m(-3) d(-1) (2.9 kg total solids (TS) m(-3) d(-1)) and HRT of 26 d produced specific methane yields of 0.6 m(3) kg(-1) VS (added waste) (0.63 m(3) kg(-1) VS(added waste)). Operating at a higher OLR of 4.2 kgVS m(-3) d(-1) (4.4 kg TS m(-3) d(-1)) and 40 d HRT produced 0.5 m(3) of methane kg(-1) VS (added waste) (0.63-0.52 m(3) kg(-1) TS (added waste). Up to 70% of TS of industrial orange waste (11.6% TS) was methanised. Further increase in OLR to 5.6 kg VS m(-3) d(-1) (5.9 kg TS m(-3) d(-1); HRT of 20 d) resulted in an unstable and non-functional digester process shown directly through complete cessation of methanogenesis, drop in methane content, reduced pH and increase in volatile fatty acid (VFA) concentrations, especially acetate and soluble chemical oxygen demand. A pH adjustment (from an initial 3.2 to ca. 8) for the low pH orange waste was necessary and was found to be a crucial factor for stable digester operation as the process showed a tendency to be inhibited due to accumulation of VFAs and decrease in digester pH. Aerobic post-treatment of digestate resulted in removal of ammonia and VFAs. PMID:16865918

  8. 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).

  9. Adenylyl cyclases in the digestive system

    PubMed Central

    Sabbatini, Maria Eugenia; Gorelick, Fred; Glaser, Shannon

    2015-01-01

    Adenylyl cyclases (ACs) are a group of widely distributed enzymes whose functions are very diverse. There are nine known transmembrane AC isoforms activated by Gαs. Each has its own pattern of expression in the digestive system and differential regulation of function by Ca2+ and other intracellular signals. In addition to the transmembrane isoforms, one AC is soluble and exhibits distinct regulation. In this review, the basic structure, regulation and physiological roles of ACs in the digestive system are discussed. PMID:24521753

  10. Adenylyl cyclases in the digestive system.

    PubMed

    Sabbatini, Maria Eugenia; Gorelick, Fred; Glaser, Shannon

    2014-06-01

    Adenylyl cyclases (ACs) are a group of widely distributed enzymes whose functions are very diverse. There are nine known transmembrane AC isoforms activated by Gαs. Each has its own pattern of expression in the digestive system and differential regulation of function by Ca(2+) and other intracellular signals. In addition to the transmembrane isoforms, one AC is soluble and exhibits distinct regulation. In this review, the basic structure, regulation and physiological roles of ACs in the digestive system are discussed. PMID:24521753

  11. 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

  12. 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.

  13. INACTIVATION OF ENTERIC PATHOGENS DURING AEROBIC DIGESTION OF WASTEWATER SLUDGE

    EPA Science Inventory

    The effects of aerobic and anaerobic digestion on enteric viruses, enteric bacteria, total aerobic bacteria, and intestinal parasites were studied under laboratory and field conditions. Under laboratory conditions, the temperature of the sludge digestion was the major factor infl...

  14. MICROBIAL DESTRUCTIONS ACHIEVED BY FULL-SCALE ANAEROBIC DIGESTION

    EPA Science Inventory

    As part of studies undertaken to investigate the pathogen reducing capabilities of conventional sludge stabilization procedures, microbial reductions produced by mesophilic and thermophilic digestion at the Los Angeles Hyperion Plant were examined. Samples from the digester feed ...

  15. Impact of structural characteristics on starch digestibility of cooked rice.

    PubMed

    Tamura, Masatsugu; Singh, Jaspreet; Kaur, Lovedeep; Ogawa, Yukiharu

    2016-01-15

    To examine the impact of structural characteristics of cooked rice grains on their starch digestibility, a simulated in vitro gastro-small intestinal digestion technique was applied to intact and homogenised cooked rice samples. The starch hydrolysis percentage increased during simulated small intestinal digestion, in which approximately 65% and 24% of the starch was hydrolysed within the first 5min, for homogenised and intact cooked rice, respectively. The kinetic constant of homogenised cooked rice, which was regarded as an estimated digestion rate, was ∼8 times higher than the intact cooked rice. The homogenised and intact samples were also examined for any microstructural changes occurring during the in vitro digestion process using fluorescent and scanning electron microscopy. In the intact samples, the aleurone layers of the endosperm remained as thin-film like layers during in vitro digestion and thus may be regarded as less digestible materials that influence cooked rice digestibility. PMID:26258706

  16. 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.

  17. Comparison of digestate from solid anaerobic digesters and dewatered effluent from liquid anaerobic digesters as inocula for solid state anaerobic digestion of yard trimmings.

    PubMed

    Xu, Fuqing; Wang, Feng; Lin, Long; Li, Yebo

    2016-01-01

    To select a proper inoculum for the solid state anaerobic digestion (SS-AD) of yard trimmings, digestate from solid anaerobic digesters and dewatered effluent from liquid anaerobic digesters were compared at substrate-to-inoculum (S/I) ratios from 0.2 to 2 (dry basis), and total solids (TS) contents from 20% to 35%. The highest methane yield of around 244L/kg VSfeed was obtained at an S/I ratio of 0.2 and TS content of 20% for both types of inoculum. The highest volumetric methane productivity was obtained with dewatered effluent at an S/I ratio of 0.6 and TS content of 24%. The two types of inoculum were found comparable regarding methane yields and volumetric methane productivities at each S/I ratio, while using dewatered effluent as inoculum reduced the startup time. An S/I ratio of 1 was determined to be a critical level and should be set as the upper limit for mesophilic SS-AD of yard trimmings. PMID:26575617

  18. Delivery Systems for Distance Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Schamber, Linda

    This ERIC digest provides a brief overview of the video, audio, and computer technologies that are currently used to deliver instruction for distance education programs. The video systems described include videoconferencing, low-power television (LPTV), closed-circuit television (CCTV), instructional fixed television service (ITFS), and cable…

  19. 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…

  20. Reflective Practice and Professional Development. ERIC Digest.

    ERIC Educational Resources Information Center

    Ferraro, Joan M.

    Reflective practice can be beneficial to preservice and inservice teacher professional development. This digest reviews the concept, levels, techniques for, and benefits of reflective practice. Donald Schon introduced the concept in 1987, and since then, many schools, colleges, and departments of education have begun designing teacher education…

  1. Using Technology in Remedial Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Keup, Jennifer Rinella

    This digest discusses two specific computer-aided instruction systems used in two-year colleges in the United States and Canada, and addresses critical points regarding system implementation in remedial education programs. As developed in the Nova Scotia Community College System in Canada, the INVEST computer system provides literacy-based…

  2. 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,…

  3. Career Counseling with Street Youth. ERIC Digest.

    ERIC Educational Resources Information Center

    Redekopp, Dave E.; And Others

    A variety of programs have unsuccessfully attempted to address the career development needs of street youth (defined here as 16-24 year olds with no fixed address, low social support, and who support themselves through street activities such as prostitution, theft, and drug-dealing). This digest describes "Skills Plus," a pre-employability program…

  4. 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;…

  5. 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,…

  6. 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 organizations, the…

  7. 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…

  8. Some Evaluation Questions. ERIC/AE Digest.

    ERIC Educational Resources Information Center

    Shadish, William

    This digest illustrates the variety of basic and theoretical issues in evaluation with which aspiring evaluators should be conversant in order to claim that they know the knowledge base of their profession. Coverage of the issues includes: the four steps in the logic of evaluation; whether qualitative evaluations are valid; whether it matters if…

  9. 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…

  10. 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…

  11. Enrollment Trends in Community Colleges. ERIC Digest.

    ERIC Educational Resources Information Center

    Andrews, Hans A.

    This digest identifies three major enrollment trends presently affecting community colleges. The three types of students--dual credit, reverse transfer, and job retraining--are likely to continue to increase in number in the near future. Dual-credit, in which secondary school students enroll in courses that receive both high school and college…

  12. 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...

  13. 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…

  14. 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 designs…

  15. Action Research in Science Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Feldman, Allan; Capobianco, Brenda

    This digest provides an introduction to action research in science education and includes examples of how action research has been used to improve teaching and learning, as well as suggested resources for those seeking to incorporate action research into their own teaching or research. Action research is defined and is examined in science…

  16. Technology Options for Libraries. ERIC Digest.

    ERIC Educational Resources Information Center

    Schamber, Linda

    This two-page digest briefly outlines some of the technological trends in updating a library, and briefly discusses the administrative issues and strategies involved. It begins by describing the wholly integrated information environment, which would include: (1) public-access personal and professional communications networks; (2) information…

  17. Optical Disk Formats: A Briefing. ERIC Digest.

    ERIC Educational Resources Information Center

    Schamber, Linda

    This digest begins with a brief description and review of the development of optical disks. Optical disk formats are then described by capability: Read Only Memory (ROM), Write Once, Read Many (WORM), Interactive (I), and Erasable (E); forms of information (audio, text or data, video or graphics, or a combination); and disk size (most often 12 or…

  18. Your Digestive System and How It Works

    MedlinePlus

    ... that the body digests into smaller molecules called amino acids. The body absorbs amino acids through the small intestine into the blood, which ... into the bloodstream. The bloodstream carries simple sugars, amino acids, glycerol, and some vitamins and salts to the ...

  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. Teaching about Judicial Review. ERIC Digest.

    ERIC Educational Resources Information Center

    Patrick, John J.

    Judicial review is a fundamental facet of constitutional government in the United States. Invented during the founding of the United States, judicial review has spread to most constitutional democracies of the world. This digest discusses: (1) the concept of judicial review; (2) the origin of this concept; (3) the uses of this concept in U.S.…

  1. 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…

  2. Knowledge Management for Higher Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Milam, John H., Jr.

    This digest describes the emerging study of Knowledge Management (KM), a field that has much to offer administrators in higher education. KM principles recognize that it is important for organizations to "know what they know." It is the organized complexity of collaborative work to share and use information across all aspects of an institution…

  3. Reconceptualizing Professional Teacher Development. ERIC Digest.

    ERIC Educational Resources Information Center

    ERIC Clearinghouse on Teaching and Teacher Education, Washington, DC.

    This digest highlights ways in which new and seasoned teachers are developing a repertoire of skills and knowledge that complement education reform efforts. For example, rather than seeing each stage of a teacher's professional life as distinct and separate, a more holistic view of the development of teacher from novice to advanced practitioner is…

  4. Contract Faculty in Higher Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Holub, Tamara

    This Digest discusses issues related to full-time, nontenure track, contract college faculty, sometimes called contingent faculty. Recent data from several sources show that the opportunities for tenure are declining, while the numbers of nontenure positions are increasing. Part of the increase in full-time nontenure faculty is due to the decrease…

  5. 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…

  6. Professional Standards Development: Teacher Involvement. ERIC Digest.

    ERIC Educational Resources Information Center

    Abdal-Haqq, Ismat

    This digest provides a brief overview of the work of several influential standards-setting bodies established during the last decade and summarizes the primary ways in which classroom teachers participate in deriving, testing, implementing, and evaluating standards. The federal government is helping to shape the movement to develop rigorous…

  7. Fax for Library Services. ERIC Digest.

    ERIC Educational Resources Information Center

    Spitzer, Kathleen L.

    This digest discusses how libraries of all types are using the facsimile (or "fax") machine to meet users' information needs. A definition of facsimile technology includes the components of a fax machine, the four types of fax machines, and the recent development of the "fax board," which allows a computer to transmit information to other fax…

  8. The anaerobic digestion of solid organic waste.

    PubMed

    Khalid, Azeem; Arshad, Muhammad; Anjum, Muzammil; Mahmood, Tariq; Dawson, Lorna

    2011-08-01

    The accumulation of solid organic waste is thought to be reaching critical levels in almost all regions of the world. These organic wastes require to be managed in a sustainable way to avoid depletion of natural resources, minimize risk to human health, reduce environmental burdens and maintain an overall balance in the ecosystem. A number of methods are currently applied to the treatment and management of solid organic waste. This review focuses on the process of anaerobic digestion which is considered to be one of the most viable options for recycling the organic fraction of solid waste. This manuscript provides a broad overview of the digestibility and energy production (biogas) yield of a range of substrates and the digester configurations that achieve these yields. The involvement of a diverse array of microorganisms and effects of co-substrates and environmental factors on the efficiency of the process has been comprehensively addressed. The recent literature indicates that anaerobic digestion could be an appealing option for converting raw solid organic wastes into useful products such as biogas and other energy-rich compounds, which may play a critical role in meeting the world's ever-increasing energy requirements in the future. PMID:21530224

  9. 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); (3) Science…

  10. 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…

  11. The Benefits of Information Technology. ERIC Digest.

    ERIC Educational Resources Information Center

    Kosakowski, John

    To be effective, technology cannot exist in a vacuum, but must become part of the whole educational environment. New measures of evaluation are under development which would help to better define the role of technology in its wider context. This ERIC digest summarizes the observed benefits of technology implementation and addresses the importance…

  12. Facilitative Leadership. ERIC Digest, Number 96.

    ERIC Educational Resources Information Center

    Lashway, Larry

    Influenced by leadership developments in the private sector, educational researchers have increasingly focused their attention on "transformational" models of leadership that emphasize collaboration and empowerment. The facilitative leader's role is to foster the involvement of employees at all different levels. This digest summarizes current…

  13. Managing Computer Software Collections. ERIC Digest.

    ERIC Educational Resources Information Center

    McLaughlin, Pamela

    This information digest discusses current issues in the management of software collections and outlines several possible options for the cataloging and processing of microcomputer software and courseware. A statement of the problem indicates that treatment of microcomputer software is highly dependent on the type of library, size of the…

  14. ACTFL Speaking Proficiency Guidelines. ERIC Digest.

    ERIC Educational Resources Information Center

    Stansfield, Charles W.

    This digest focuses on the American Council on the Speaking of Foreign Languages (ACTFL) Speaking Proficiency Guidelines. The history and development of the ACTFL Proficiency Guidelines (originally, the ACTFL Provisional Proficiency Guidelines) are reviewed, the generic characteristics of each level of the speaking guidelines are presented in…

  15. 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…

  16. Stereotypes of Asian American Students. ERIC Digest.

    ERIC Educational Resources Information Center

    Kim, Angela; Yeh, Christine J.

    This digest discusses various negative and positive Asian American stereotypes and explores how school practices and individual educators, consciously or unconsciously, may reinforce them. This has important negative social, political, and economic ramifications for Asian Americans. While Asian Americans are often characterized as the "model…

  17. Bilingual Special Education. ERIC Digest #E496.

    ERIC Educational Resources Information Center

    Baca, Leonard M.; Cervantes, Hermes T.

    This digest estimates that 948,000 U.S. children may both be linguistically different and have disabilities. The nature of instruction and educational placement of these students should be based on the degree of disability, level of language proficiency in both English and the primary language, and intellectual capacity. Placement decisions should…

  18. 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…

  19. 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…

  20. 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"…

  1. 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…

  2. 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.…

  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 cultural…

  4. 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…

  5. Mental Retardation: Update 2002. ERIC Digest.

    ERIC Educational Resources Information Center

    Hourcade, Jack

    This digest provides an overview of mental retardation in children and adults. It begins by discussing the definition of mental retardation and the three components that are required for an accurate diagnosis: an IQ score of approximately 70 or below, a determination of deficits in adaptive behavior, and origins of the disability prior to age 18.…

  6. Manejo de riesgo (Risk Management). ERIC Digest.

    ERIC Educational Resources Information Center

    Gaustad, Joan

    The ordinary conduct of school business is accompanied today by risks that were rare or unknown a few decades ago. This ERIC Digest in Spanish discusses how risk management, a concept long used by corporate decision makers, can help school boards and administrators conserve their districts' assets. Risk management is a coordinated effort to…

  7. Hypertext: Behind the Hype. ERIC Digest.

    ERIC Educational Resources Information Center

    Bevilacqua, Ann F.

    This digest begins by defining the concept of hypertext and describing the two types of hypertext--static and dynamic. Three prototype applications are then discussed: (1) Intermedia, a large-scale multimedia system at Brown University; (2) the Perseus Project at Harvard University, which is developing interactive courseware on classical Greek…

  8. 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…

  9. Shared Governance in Community Colleges. ERIC Digest.

    ERIC Educational Resources Information Center

    Schuetz, Pam

    This digest discusses shared governance in community colleges and identifies issues highlighted by recent shared governance experiences. Governance structure in public community colleges tends to have many variations at both the state and local level. Shared governance is a pattern of self-government in which decision-making is shared among…

  10. Status of Dance in Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Overby, Lynnette Young

    This Digest introduces dance as an art form characterized by use of the human body as a vehicle of expression. Organized into three sections, the first examines the rationale for dance programs in education, presenting opportunities for development of critical thinking and analytical skills; cooperation and teamwork; self-expression and…

  11. Teacher Mentoring as Professional Development. ERIC Digest.

    ERIC Educational Resources Information Center

    Huling, Leslie; Resta, Virginia

    Teacher mentoring programs have increased dramatically since the early 1980s as a vehicle to support and retain novice teachers. However, researchers and facilitators of mentoring programs are recognizing that mentors also derive substantial benefits from the mentoring experience. This digest examines research on how mentoring contributes to the…

  12. 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…

  13. 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…

  14. 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 or…

  15. Helping the Underachiever in Reading. ERIC Digest.

    ERIC Educational Resources Information Center

    Quatroche, Diana J.

    Noting that the development of effective intervention programs and instructional strategies for the struggling or underachieving reader continues to be a topic of concern, this Digest first reviews the current status of reading performance, based on the 1998 National Assessment of Educational Progress. It then reports on the importance of early…

  16. 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…

  17. Motivation and Middle School Students. ERIC Digest.

    ERIC Educational Resources Information Center

    Anderman, Lynley Hicks; Midgley, Carol

    Research has shown a decline in motivation and performance for many children as they move from elementary school into middle school; however, research has also shown that the nature of motivational change on entry to middle school depends on characteristics of the learning environment in which students find themselves. This Digest outlines some…

  18. Diversity Digest. Volume 8, Number 2

    ERIC Educational Resources Information Center

    Giles, Mark, Ed.

    2004-01-01

    This issue of "Diversity Digest" contains articles and resources focused on the lasting lessons, legacies, and spirit of the 1954 "Brown v. Board of Education" decision. This year of the fiftieth anniversary, filled with ceremonies, celebrations, and commemorations of that decision has highlighted many well known and lesser known people who fought…

  19. 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.…

  20. Mathematics Achievement in Rural Schools. ERIC Digest.

    ERIC Educational Resources Information Center

    Howley, Craig B.

    This digest examines the best evidence available on mathematics achievement in rural schools and offers recommendations for further research. Findings on the mathematics achievement of secondary students are presented, based on analyses of the National Assessment of Educational Progress (NAEP) in 1996 and 2000, the Longitudinal Study of American…

  1. 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…

  2. 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.

  3. 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.

  4. Political Communication via the Media. ERIC Digest.

    ERIC Educational Resources Information Center

    Aiex, Nola Kortner; Gottlieb, Stephen S.

    Noting that critics charge that news reporting focuses on the superficial, personal characteristics of candidates and ignores the issues underlying elections, this Digest examines the relationship between the political process and political communication through the media. It addresses the power of advertising, cyberspace political communication,…

  5. Gender Equity in Vocational Education. WEEA Digest.

    ERIC Educational Resources Information Center

    McAuliffe, Anne, Ed.

    This digest contains three articles on gender equity in vocational education, especially in relation to the provisions of the Vocational Education Act of 1976 and the Carl Perkins Act of 1984. "Gender Equity in Vocational Education" (Debra J. Robbin) describes interviews with students at a New England vocational school, in which they reported a…

  6. 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…

  7. Test Accommodations for LEP Students. ERIC Digest.

    ERIC Educational Resources Information Center

    Stansfield, Charles; Rivera, Charlene

    This digest presents an overview of accommodations for students of limited English proficiency (LEP) and an overview of inclusion practices on statewide assessments, with emphasis on the accommodation known as linguistic simplification. The inclusion of LEP students in statewide testing programs over the last decade has been uneven. In the…

  8. Selecting and Retaining Teacher Mentors. ERIC Digest.

    ERIC Educational Resources Information Center

    Mullinix, Bonnie B.

    This digest examines considerations and strategies for selecting and retaining teacher mentors, suggesting that the degree to which mentors are meaningfully engaged in the mentoring process may have a significant impact on a program's success. Strategies for recruiting mentors range from opportunistic appointment to promoting self-nomination to…

  9. 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…

  10. 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…

  11. 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…

  12. 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…

  13. Reteniendo los directores (Retaining Principals). ERIC Digest.

    ERIC Educational Resources Information Center

    Hertling, Elizabeth

    This digest in Spanish examines the reasons why--outside of retirement--school principals leave their jobs. It also lists strategies districts can employ to retain principals. Many principals exit their profession because of the long hours, the workload and complexity of the job, the unending supervision of evening activities, the minimal pay…

  14. Gender Equity for Males. WEEA Digest.

    ERIC Educational Resources Information Center

    Flood, Craig, Ed.; Bates, Percy, Ed.; Potter, Julia, Ed.

    Traditionally, the term "gender equity" is associated with equalizing the playing field for girls. However, gender equity by definition applies to both genders. This digest states that, in the best possible scenario, gender equitable education provides equal opportunities and enables each student to reach his or her potential, reducing the gender…

  15. Discovering Mathematical Talent. ERIC Digest #E482.

    ERIC Educational Resources Information Center

    Miller, Richard C.

    This digest offers guidance in identifying and nurturing mathematical talent in children. Mathematical talent is defined and the characteristics of mathematically talented students are listed. Some mathematically talented students do not achieve well in school mathematics due to a mismatch between the student and the mathematics program. Ways that…

  16. 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…

  17. Loneliness in Young Children. ERIC Digest.

    ERIC Educational Resources Information Center

    Bullock, Janis R.

    Loneliness is a significant problem than can predispose young children to immediate and long-term negative consequences. This Digest presents an overview of loneliness, with suggestions for practitioners on how they can apply the research in early childhood settings. Children who feel lonely often experience poor peer relationships and feelings of…

  18. 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"; the…

  19. What Is An Expert System? ERIC Digest.

    ERIC Educational Resources Information Center

    Boss, Richard W.

    This digest describes and defines the various components of an expert system, e.g., a computerized tool designed to enhance the quality and availability of knowledge required by decision makers. It is noted that expert systems differ from conventional applications software in the following areas: (1) the existence of the expert systems shell, or…

  20. 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…

  1. Emerging Challenges for Community Colleges. ERIC Digest.

    ERIC Educational Resources Information Center

    Schuetz, Pam

    This digest is drawn from the spring 2002 issue of New Directions for Community Colleges, titled "Next Steps for the Community College." It summarizes three overlapping challenges facing colleges in the coming decade: educating a more diverse student body, assessing student outcomes, and maintaining the educated workforce needed to meet the…

  2. Negotiation Research Digest, April 1967-June 1975.

    ERIC Educational Resources Information Center

    Negotiation Research Digest, 1975

    1975-01-01

    The Negotiation Research Digest (NRD) was compiled by the Research Division of the National Education Association (NEA). It began publication in April 1967 and, after 81 issues, ceased publication in June 1975. A normal publication year involved 10 issues published from September through June, skipping July and August. Each issue contained…

  3. 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 ...

  4. Learning Disabilities Overview: Update 2002. ERIC Digest.

    ERIC Educational Resources Information Center

    Boudah, Daniel J.; Weiss, Margaret P.

    This digest of what is currently known about learning disabilities (LD) begins with a brief vignette and then notes that individuals with LD generally have average or above average intelligence, yet underachieve in academics. Five common problem areas for individuals with LD are also examined: reading, written language, math, memory, and…

  5. DISACCHARIDE DIGESTION: CLINICAL AND MOLECULAR ASPECTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sugars normally are absorbed in the small intestine. When carbohydrates are malabsorbed, the osmotic load produced by the high amount of low molecular weight sugars and partially digested starches in the small intestine can cause symptoms of intestinal distention, rapid peristalsis, and diarrhea. Co...

  6. Open Questions in Mathematics Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Britton, Edward; Raizen, Senta; Kaser, Joyce; Porter, Andrew

    This ERIC Digest presents highlights and recommendations from a working forum (Britton, Raizen, Kaser, and Porter, 2000) in which participants considered diversity and equity issues in mathematics and science education with special emphasis on research directions for the future. An overview of needed research, gender issues in mathematics, and the…

  7. 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…

  8. Multicultural Issues in Outdoor Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Roberts, Nina S.; Rodriguez, Donald A.

    The 1990s saw the outdoor education community undergo a process of critical redefinition as it attempted to address multicultural issues. This digest defines multicultural education, reviews the current status of multicultural diversity in outdoor education, poses questions for researchers and practitioners, and offers suggestions for relevant…

  9. 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…

  10. REDUCTIONS OF ENTERIC MICROORGANISMS DURING AEROBIC SLUDGE DIGESTION: COMPARISON OF CONVENTIONAL AND AUTOHEATED DIGESTERS

    EPA Science Inventory

    The objectives of the investigation were to: (1) determine the seasonal variations in sludge stabilization and reductions in the densities of indicator organisms, Salmonella ssp., and enteroviruses that occur with conventional aerobic digestion in cold climates; and (2) demonstra...

  11. 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...

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

    PubMed Central

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

    2014-01-01

    A novel microfluidic protein digestion system with 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. PMID:25511010

  13. Foaming phenomenon in bench-scale anaerobic digesters.

    PubMed

    Siebels, Amanda M; Long, Sharon C

    2013-04-01

    The Madison Metropolitan Sewerage District (The District) in Madison, Wisconsin has been experiencing seasonal foaming in their anaerobic biosolids digesters, which has occurred from mid-November to late June for the past few years. The exact cause(s) of foaming is unknown. Previous research findings are unclear as to whether applications of advanced anaerobic digestion processes reduce the foaming potential of digesters. The object of this study was to investigate how configurations of thermophilic and acid phase-thermophilic anaerobic digestion would affect foaming at the bench-scale level compared to single stage mesophilic digestion for The District. Bench-scale anaerobic digesters were fed with a 4 to 4.5% by dry weight of solids content blend of waste activated sludge (WAS) and primary sludge from The District. Foaming potential was monitored using Alka-Seltzer and aeration foaming tests. The bench-scale acid phase-thermophilic digester had a higher foaming potential than the bench-scale mesophilic digester. These results indicate that higher temperatures increase the foaming potential of the bench-scale anaerobic digesters. The bench-scale acid phase-thermophilic digesters had a greater percent (approximately 5 to 10%) volatile solids destruction and a greater percent (approximately 5 to 10%) total solids destruction when compared to the bench-scale mesophilic digester. Overall, for the full-scale foaming experienced by The District, it appears that adding an acid phase or switching to thermophilic digestion would not alleviate The District's foaming issues. PMID:23697241

  14. 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. PMID:11936112

  15. Full-scale application of anaerobic digestion process with partial ozonation of digested sludge.

    PubMed

    Yasui, H; Komatsu, K; Goel, R; Li, Y Y; Noike, T

    2005-01-01

    For improving sludge digestion and biogas recovery, a new anaerobic digestion process combined with ozonation was tested at a full-scale unit for 2 years and its performance was compared with a simultaneously operated conventional anaerobic digestion process. The new process requires two essential modifications, which includes ozonation for enhancing the biological degradability of sludge organics and concentrating of solids in the digester through a solid/liquid separation for extension of SRT. These modifications resulted in high VSS degradation efficiency of ca. 88%, as much as 1.3 times of methane production and more than 70% reduction in dewatered sludge cake production. Owing to accumulation of inorganic solids in the digested sludge, water content of the dewatered sludge cake also reduced from 80% to 68%. An energy analysis suggested that no supplemental fuel was necessary for the subsequent incineration of the cake from the new process scheme. The process is suitable to apply to a low-loaded anaerobic digestion tank, where power production is used. PMID:16180435

  16. 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

  17. 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.

  18. On-farm anaerobic digester and fuel alcohol plant

    SciTech Connect

    Not Available

    1985-01-01

    An anaerobic digestion system was constructed and set up on a southern Illinois farm. The anaerobic digestion system was designed to be coupled with a fuel alcohol plant constructed by the farm family as part of an integrated farm energy system. The digester heating can be done using waste hot water from the alcohol plant and biogas from the digester can be used as fuel for the alcohol production. The anaerobic digestion system is made up of the following components. A hog finishing house, which already had a slotted floor and manure pit beneath it, was fitted with a system to scrape the manure into a feed slurry pit constructed at one end of the hog house. A solids handling pump feeds the manure from the feed slurry pit into the digester, a 13,000 gallon tank car body which has been insulated with styrofoam and buried underground. Another pump transfers effluent (digested manure) from the digester to a 150,000 gallon storage tank. The digested manure is then applied to cropland at appropriate times of the year. The digester temperature is maintained at the required level by automated hot water circulation through an internal heat exchanger. The biogas produced in the digester is pumped into a 32,000 gallon gas storage tank.

  19. 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.

  20. Evaluating anaerobic digestion for reduction of organic wastes

    SciTech Connect

    Hartung, H.A.

    1994-12-31

    A small-scale anaerobic digestion test has been developed for monitoring start-up work with inoperative digesters. The test is described and variables critical to its consistent operation are detailed. The method has been used in many anaerobic digestion studies, including evaluation of the digestibility of various municipal solid wastes like grass and hedge clippings, garbage and newspapers. Digestion rates are expressed in terms of the rate of production of combustible gas and the retention time needed for a fixed degree of volatile solids destruction. An example shows the advantage of digesting selected combined charges, and it is suggested that this approach might be fruitful with many toxic organic materials. Application of this test to find the digestion rates of some high-yield biomass crops is also described.

  1. 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. PMID:2238434

  2. 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

  3. Digestion and Postprandial Metabolism in the Elderly.

    PubMed

    Milan, Amber M; Cameron-Smith, David

    2015-01-01

    The elderly are an increasing segment of the population. Despite the rapid gains in medical knowledge and treatments, older adults are more likely to experience chronic illnesses that decrease quality of life and accelerate mortality. Nutrition is a key modifiable lifestyle factor which greatly impacts chronic disease risk. Yet despite the importance of nutrition, relatively little is known of the impact of advancing age on the gastrointestinal function, the digestive responses, and the post-meal metabolic adaptations that occur in response to ingested food. Knowledge of the age-related differences in digestion and metabolism in the elderly is essential to the development of appropriate nutritional recommendations for the maintenance of optimal health and prevention of disease. PMID:26602572

  4. 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.

  5. Nucleotide `maps' of digests of deoxyribonucleic acid

    PubMed Central

    Murray, K.

    1970-01-01

    Various digests of 32P-labelled DNA were examined by two-dimensional ionophoresis on cellulose acetate and DEAE-cellulose paper. The products from digestion with pancreatic deoxyribonuclease and Neurospora crassa endonuclease were qualitatively closely similar, but very complex, and were used to investigate the mapping behaviour of nucleotides in various ionophoretic systems. Ionophoresis on DEAE-cellulose paper in triethylamine carbonate, pH 9.7, followed by ionophoresis in the second dimension at pH1.9 gave high resolution of nucleotides in very complex mixtures and permitted the fractionation of larger quantities than is possible on cellulose acetate. High resolution of nucleotides in compact spots was obtained with two-dimensional ionophoresis on cellulose acetate and AE-cellulose paper, a system that is a useful supplement to those based on DEAE-cellulose paper. ImagesPLATE 7PLATE 1PLATE 2PLATE 3PLATE 4PLATE 5PLATE 6 PMID:5476726

  6. 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

  7. Nuclease digestion studies of chromatin structure

    SciTech Connect

    Deutsch, S.M.

    1987-01-01

    Micrococcal nuclease, which preferentially cleaves linker DNA in chromatin, was immobilized by covalent attachment to CNBr-activated agarose beads and used to study the accessibility of linker DNA in chromatin fibers prepared from chicken erythrocyte nuclei. This immobilized nuclease was able to cleave chromatin fibers into the typical pattern of fragments corresponding to multiples of mononucleosomes. Cleavage from only the ends of the fibers was ruled out by examining the products of cleavage of fibers end-labelled with /sup 35/P. Comparison of the rate of digestion by immobilized and soluble micrococcal nuclease indicated that the fiber structure does not significantly affect access to linker DNA. The absence of an effect of reducing temperatures on the rate of digestion of fibers, as compared to short oligonucleosomes, indicated that breathing motions to allow access to the fiber interior were not required for cleavage of linker DNA.

  8. 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.

  9. American Laundry Digest Buyer's Guide. Manufacturers directory.

    PubMed

    1991-06-15

    The following is the annual American Laundry Digest Buyer's Guide which is being circulated to all segments of the laundry industry. The Guide contains a list of manufacturers who responded to our questionnaire. This is followed by a list of product categories and the various manufacturers who make these products. You may contact these companies directly or by using the reader service card in this issue. PMID:10112431

  10. Bronchoalveolar Lavage and Lung Tissue Digestion

    PubMed Central

    Han, Hongwei; Ziegler, Steven F.

    2016-01-01

    Bronchoalveolar lavage (BAL) is a simple but valuable and typically performed technique commonly used for studying the pathogenesis of lung diseases such as asthma and COPD. Cell counts can be combined with new methods for examining inflammatory responses, such as ELISA, Flow cytometric analysis, immunohistochemistry, quantitative polymerase chain reaction, and HPLC to assess cellular expression for inflammatory cytokines and growth factor. Here we describe a basic procedure to collect BAL fluid and digest lung tissue for assessing a number of pulmonary components.

  11. Binge Drinking on College Campuses. ERIC Digest.

    ERIC Educational Resources Information Center

    Kellogg, Karen

    This digest discusses binge drinking on U.S. college campuses. Male binge drinking is defined as five or more drinks in a row one or more times during a 2-week period; female binge drinking is defined as four or more drinks in a row one or more times during a two-week period. A drink is defined as twelve ounces of beer or wine cooler, four ounces…

  12. 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…

  13. 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.

  14. Anaerobic digestion of space mission wastes.

    PubMed

    Chynoweth, D P; Owens, J M; Teixeira, A A; Pullammanappallil, P; Luniya, S S

    2006-01-01

    The technical feasibility of applying leachbed high-solids anaerobic digestion for reduction and stabilization of the organic fraction of solid wastes generated during space missions was investigated. This process has the advantages of not requiring oxygen or high temperature and pressure while producing methane, carbon dioxide, nutrients, and compost as valuable products. Anaerobic biochemical methane potential assays run on several waste feedstocks expected during space missions resulted in ultimate methane yields ranging from 0.23 to 0.30 L g-1 VS added. Modifications for operation of a leachbed anaerobic digestion process in space environments were incorporated into a new design, which included; (1) flooded operation to force leachate through densified feedstock beds; and (2) separation of biogas from leachate in a gas collection reservoir. This mode of operation resulted in stable performance with 85% conversion of a typical space solid waste blend, and a methane yield of 0.3 Lg per g VS added after a retention time of 15 days. These results were reproduced in a full-scale prototype system. A detailed analysis of this process was conducted to design the system sized for a space mission with a six-person crew. Anaerobic digestion compared favorably with other technologies for solid waste stabilization. PMID:16784202

  15. Acid digestion demonstration (WeDID)

    SciTech Connect

    Crippen, M.D.

    1993-11-01

    Acid digestion process development began at the Hanford Site in 1972 with a beaker of laboratory acid and progressed through laboratory and pilot-scale development culminating in the Radioactive Acid Digestion Test Unit (RADTU). The RADTU was operational from 1977 through 1982 and processed over 5,000 kg of synthetic and combustible waste forms from Hanford Site operations. It routinely reacted plastics, wood, paper, cloth, ion-exchange resins, metals, and solvents. Operation of RADTU routinely gave volume reductions of 100:1 for most plastics and other combustibles. The residue was inert and was disposed of both as generated and after application of other immobilization techniques, such as calcination, addition to glass, and cement addition. The system was designed to accommodate offgas surges from highly reactive nitrated organics and successfully demonstrated that capability. The system was designed and operated under very stringent safety standards. The Weapons Destruction Integrated Demonstration (WeDID) program required a technology that could dispose of an assortment of weapon components, such as complex electronics, neutron generators, thermal batteries, plastics, cases, cables, and others. A program objective was to recycle and reuse materials wherever possible, but many unique components would need to be rendered inactive, inert, and suitable for disposal under current environmental laws. Acid digestion technology was a key candidate for treating many of the above components; it provided accepted technology for treatment of chemicals and elements that have posed disposal difficulties designated by the US Environmental Protection Agency (EPA).

  16. 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. PMID:26711173

  17. 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.

  18. Baltimore Zoo digester project. Final report. [Elephants

    SciTech Connect

    Gibson, P.W.

    1980-01-01

    The results of a project to produce methane using the manure from zoo animals as a feedstock is presented. Two digesters are in operation, the first (built in 1974) utilizing wastes from the Hippo House and a second (built in 1980) utilizing wastes from the Elephant House. Demonstrations on the utilization of the gas were performed during zoo exhibits. The Elephant House Digester has a capacity of 4200 gallons and a floating gas dome which can retain at least 150 cu ft of gas. Solar energy has been incorporated into the design to maintain digester temperature at 95/sup 0/F. The system produces 50 cu ft per day. After cleaning the gas, it is used to generate electricity to power an electric light, a roof fan, and an air conditioner. The gas is also used to operate a gas range and a gas lamp. During the opening day exhibit, 50 meals were cooked using the bio-gas from just 2 elephants. (DMC)

  19. 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. PMID:26979664

  20. 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.

  1. 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. PMID:26092475

  2. Quality assessment of digested sludges produced by advanced stabilization processes.

    PubMed

    Braguglia, C M; Coors, A; Gallipoli, A; Gianico, A; Guillon, E; Kunkel, U; Mascolo, G; Richter, E; Ternes, T A; Tomei, M C; Mininni, G

    2015-05-01

    The European Union (EU) Project Routes aimed to discover new routes in sludge stabilization treatments leading to high-quality digested sludge, suitable for land application. In order to investigate the impact of different enhanced sludge stabilization processes such as (a) thermophilic digestion integrated with thermal hydrolysis pretreatment (TT), (b) sonication before mesophilic/thermophilic digestion (UMT), and (c) sequential anaerobic/aerobic digestion (AA) on digested sludge quality, a broad class of conventional and emerging organic micropollutants as well as ecotoxicity was analyzed, extending the assessment beyond the parameters typically considered (i.e., stability index and heavy metals). The stability index was improved by adding aerobic posttreatment or by operating dual-stage process but not by pretreatment integration. Filterability was worsened by thermophilic digestion, either alone (TT) or coupled with mesophilic digestion (UMT). The concentrations of heavy metals, present in ranking order Zn > Cu > Pb > Cr ~ Ni > Cd > Hg, were always below the current legal requirements for use on land and were not removed during the processes. Removals of conventional and emerging organic pollutants were greatly enhanced by performing double-stage digestion (UMT and AA treatment) compared to a single-stage process as TT; the same trend was found as regards toxicity reduction. Overall, all the digested sludges exhibited toxicity to the soil bacterium Arthrobacter globiformis at concentrations about factor 100 higher than the usual application rate of sludge to soil in Europe. For earthworms, a safety margin of factor 30 was generally achieved for all the digested samples. PMID:24903249

  3. 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. PMID:18561391

  4. Bioaugmentation of overloaded anaerobic digesters restores function and archaeal community.

    PubMed

    Tale, V P; Maki, J S; Zitomer, D H

    2015-03-01

    Adding beneficial microorganisms to anaerobic digesters for improved performance (i.e. bioaugmentation) has been shown to decrease recovery time after organic overload or toxicity upset. Compared to strictly anaerobic cultures, adding aerotolerant methanogenic cultures may be more practical since they exhibit higher methanogenic activity and can be easily dried and stored in ambient air for future shipping and use. In this study, anaerobic digesters were bioaugmented with both anaerobic and aerated, methanogenic propionate enrichment cultures after a transient organic overload. Digesters bioaugmented with anaerobic and moderately aerated cultures recovered 25 and 100 days before non-bioaugmented digesters, respectively. Increased methane production due to bioaugmentation continued a long time, with 50-120% increases 6 to 12 SRTs (60-120 days) after overload. In contrast to the anaerobic enrichment, the aerated enrichments were more effective as bioaugmentation cultures, resulting in faster recovery of upset digester methane and COD removal rates. Sixty days after overload, the bioaugmented digester archaeal community was not shifted, but was restored to one similar to the pre-overload community. In contrast, non-bioaugmented digester archaeal communities before and after overload were significantly different. Organisms most similar to Methanospirillum hungatei had higher relative abundance in well-operating, undisturbed and bioaugmented digesters, whereas organisms similar to Methanolinea tarda were more abundant in upset, non-bioaugmented digesters. Bioaugmentation is a beneficial approach to increase digester recovery rate after transient organic overload events. Moderately aerated, methanogenic propionate enrichment cultures were more beneficial augments than a strictly anaerobic enrichment. PMID:25528544

  5. 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. PMID:24569280

  6. Anaerobic digestion of high-strength cheese whey utilizing semicontinuous digesters and chemical flocculant addition

    SciTech Connect

    Barford, J.P.; Cail, R.G.; Callander, I.J.; Floyd, E.J.

    1986-11-01

    Semicontinuous digesters were used to anaerobically treat high-strength whey (70 kg/cubic m COD). A maximum loading of 16.1 kg COD/cubic m/day was obtained with soluble COD removal efficiencies greater than 99%. The use of a chemical flocculant resulted in an increased biomass concentration in the digester compared to a control, thus enabling correspondingly higher space loadings to be applied. With the onset of substantial levels of granulation of the biomass, flocculant dosage was able to be discontinued. This article discusses the performance of the digesters in detail and, briefly, the long-term operational difficulties experienced and the control strategies employed on such systems. 24 references.

  7. Slowly digestible state of starch: mechanism of slow digestion property of gelatinized maize starch.

    PubMed

    Zhang, Genyi; Sofyan, Maghaydah; Hamaker, Bruce R

    2008-06-25

    The mechanism underlying the previously reported parabolic relationship between amylopectin fine structure, represented by the weight ratio of linear short chains [degree of polymerization (DP < 13) to long chains (DP >/= 13], and slowly digestible starch (SDS) content was investigated from the viewpoint of starch retrogradation and substrate susceptibility to enzyme hydrolysis. A maize mutant sample, termed "highest long-chain starch" (HLCS) representing group I samples with a higher proportion of long chains, showed a bell-shaped SDS pattern with retrogradation time, whereas insignificant changes in SDS were found for the sample termed "highest short-chain starch" (HSCS) representing group II samples with a higher proportion of short chains. This corresponded to results from X-ray powder diffraction and differential scanning calorimetry that showed a rapid increase of crystallinity and enthalpy for HLCS during retrogradation, but negligible changes for sample HSCS. Therefore, retrogradation was associated with SDS content for group I samples, but not for group II samples. Analysis of amylopectin fine structure, SDS content, retrogradation enthalpy, SDS material debranching profile, and hydrolysis pattern demonstrated, for group I samples, that linear branched chains of DP 9-30 of amylopectin may act as anchor points to slow the digestion of branced-chain fractions of DP > 30, which constitute the major slowly digestible portion, whereas for group II samples, it is the inherent molecular structure of amylopectin with a higher amount of branches and shorter chains that is not favorable for rapid enzyme digestion. The concept of a slowly digestible starch state (SDS state) that could be a chemical or physical entity is proposed to better describe the mechanistic underpinning of the slow digestion property of starches. PMID:18512933

  8. Use of bench-scale digesters to evaluate full-scale digester performance

    SciTech Connect

    Murk, J.S.; Frieling, J.L.; Tortorici, L.D.; Dietrich, C.C.

    1980-11-01

    The use of properly designed laboratory-scale digestion facilities afforded an economical method to investigate the causes(s) of and remedies for a severe operational problem at the Encina wastewater treatment plant located in North San Diego Country, California. These studies resulted in verification that the chronic foaming problems were related to inadequate mixing and heating and led to the implementation of design and operational modifications to optimize digester performance. As a result of this program, subsequent design changes, and the dedicated efforts of the plant operators, a severe operational problem has been eliminated.

  9. 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. PMID:27243386

  10. Impact of different ratios of feedstock to liquid anaerobic digestion effluent on the performance and microbiome of solid-state anaerobic digesters digesting corn stover.

    PubMed

    Li, Yueh-Fen; Shi, Jian; Nelson, Michael C; Chen, Po-Hsu; Graf, Joerg; Li, Yebo; Yu, Zhongtang

    2016-01-01

    The objective of this study was to understand how the non-microbial factors of L-AD effluent affected the microbiome composition and successions in the SS-AD digesters using both Illumina sequencing and qPCR quantification of major genera of methanogens. The SS-AD digesters started with a feedstock/total effluent (F/Et) ratio 2.2 (half of the effluent was autoclaved) performed stably, while the SS-AD digesters started with a 4.4 F/Et ratio (no autoclaved effluent) suffered from digester acidification, accumulation of volatile fatty acids, and ceased biogas production two weeks after startup. Some bacteria and methanogens were affected by non-microbial factors of the L-AD fluent. Alkalinity, the main difference between the two F/Et ratios, may be the crucial factor when SS-AD digesters were started using L-AD effluent. PMID:26575616

  11. 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. PMID:26776247

  12. 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. PMID:26773433

  13. 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.

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

    DOE PAGESBeta

    Shi, Jinshu; Shi, Sheldon Q.; Barnes, H. Michael; Horstemeyer, Mark; Wang, Jinwu; Hassan, El-Barbary M.

    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

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. [Medical treatment of digestive neuroendocrine tumours].

    PubMed

    Panzuto, F; Nasoni, S; Delle Fave, G

    2001-09-01

    Surgery is the only therapy able to cure patients with digestive neuroendocrine tumor. However, due to the presence of diffuse metastases, radical surgery is often not feasible. In these cases, medical treatment plays a critical role, because of its ability to control symptoms in functioning tumors and to inhibit tumor growth. Different therapeutic approaches, such as chemotherapy, hepatic artery chemoembolization and targeted radio-nuclide therapy can be used alone or combined to the biologic treatment with somatostatin analogues and interferon. However, an accurate staging by imaging procedures plus a histological, immunohistochemical and biomolecular examination must be performed before planning an optimal medical treatment. PMID:11753237

  1. 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.

  2. 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.

  3. 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...

  4. 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...

  5. 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 ...

  6. 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. PMID:23402587

  7. Carbohydrate digestion in ticks and a digestive α-L-fucosidase.

    PubMed

    Moreti, R; Perrella, N N; Lopes, A R

    2013-10-01

    Digestive carbohydrases are present in many species of hematophagous Arthropoda, including ticks. In this work, Amblyomma cajennense (Ixodidae) midgut digestive carbohydrases were tracked with different substrates, resulting in the identification of a chitinase and an N-acetyl-β-glucosaminidase and the first description of a digestive α-L-fucosidase in ticks. α-L-fucosidases are involved in various physiological processes, and digestive α-L-fucosidases have been shown to be present in other types of organisms. Amblyomma cajennense α-L-fucosidase activity was isolated using acidic and salting-out precipitations and chromatographic steps in hydrophobic and cation-exchange columns. The specificity of the isolated activity as an α-L-fucosidase was confirmed by the hydrolysis of 4-methylumbelliferyl α-L-fucopyranoside and the natural substrate fucoidan and the inhibition by fucose and deoxyfuconojirimycin. The isolated activity of α-L-fucosidase forms oligomers with molecular mass of 140 kDa or 150 kDa as determined by gel filtration and non-reducing SDS-PAGE, respectively. This particular fucosidase has an optimum pH of 5.3, is stable even at high temperatures (stable for at least 2h at 50 °C), has a Km of 45 μM to the substrate 4-methylumbelliferyl α-L-fucopyranoside and IC 50% of 327 μM to fucose and 42 pM to deoxyfuconojirimycin. The presence of digestive fucosidases in hematophagous Arthropoda may be related to defence mechanisms against host-parasite interactions. PMID:23994295

  8. Protein digestibility of the same protein preparations by human and rat assays and by in vitro enzymic digestion methods.

    PubMed

    Bodwell, C E; Satterlee, L D; Hackler, L R

    1980-03-01

    The apparent and true digestibilities of the same preparations of six proteins (spray dried whole egg, cottage cheese, canned tuna, peanut flour, soy isolate, and wheat gluten) were estimated in four to five men and in rats and compared to estimates of digestibility from three different in vitro enzymic digestion procedures. For all six proteins, the correlation coefficient was 0.46 between true digestibility in humans and in rats; with values for tuna excluded, r = 0.96. With all six proteins, none of the in vitro values was significantly correlated with values from humans or rats. However, with either the three animal proteins alone or the three plant proteins alone, correlations were high (r greater than 0.90) between one or more of the in vitro estimates and the observed true or apparent human and rat digestibilities. The differences in the relationship between enzymic digestion estimates and the human digestibility estimates for plant or animal proteins suggest that for accurate prediction of protein digestibility in humans by these enzymic methods, different equations would have to be used for plant and animal proteins. For protein sources containing both plant and animal protein, use of the in vitro enzymic procedures would give only an approximate estimate of digestibility in humans. PMID:6986763

  9. Therapeutic potential of curcumin in digestive diseases

    PubMed Central

    Dulbecco, Pietro; Savarino, Vincenzo

    2013-01-01

    Curcumin is a low-molecular-weight hydrophobic polyphenol that is extracted from turmeric, which possesses a wide range of biological properties including anti-inflammatory, anti-oxidant, anti-proliferative and anti-microbial activities. Despite its diverse targets and substantial safety, clinical applications of this molecule for digestive disorders have been largely limited to case series or small clinical trials. The poor bioavailability of curcumin is likely the major hurdle for its more widespread use in humans. However, complexation of curcumin into phytosomes has recently helped to bypass this problem, as it has been demonstrated that this new lecithin formulation enables increased absorption to a level 29-fold higher than that of traditional curcuminoid products. This allows us to achieve much greater tissue substance delivery using significantly lower doses of curcumin than have been used in past clinical studies. As curcumin has already been shown to provide good therapeutic results in some small studies of both inflammatory and neoplastic bowel disorders, it is reasonable to anticipate an even greater efficacy with the advent of this new technology, which remarkably improves its bioavailability. These features are very promising and may represent a novel and effective therapeutic approach to both functional and organic digestive diseases. PMID:24409053

  10. Therapeutic potential of curcumin in digestive diseases.

    PubMed

    Dulbecco, Pietro; Savarino, Vincenzo

    2013-12-28

    Curcumin is a low-molecular-weight hydrophobic polyphenol that is extracted from turmeric, which possesses a wide range of biological properties including anti-inflammatory, anti-oxidant, anti-proliferative and anti-microbial activities. Despite its diverse targets and substantial safety, clinical applications of this molecule for digestive disorders have been largely limited to case series or small clinical trials. The poor bioavailability of curcumin is likely the major hurdle for its more widespread use in humans. However, complexation of curcumin into phytosomes has recently helped to bypass this problem, as it has been demonstrated that this new lecithin formulation enables increased absorption to a level 29-fold higher than that of traditional curcuminoid products. This allows us to achieve much greater tissue substance delivery using significantly lower doses of curcumin than have been used in past clinical studies. As curcumin has already been shown to provide good therapeutic results in some small studies of both inflammatory and neoplastic bowel disorders, it is reasonable to anticipate an even greater efficacy with the advent of this new technology, which remarkably improves its bioavailability. These features are very promising and may represent a novel and effective therapeutic approach to both functional and organic digestive diseases. PMID:24409053

  11. Mechanisms of foam formation in anaerobic digesters.

    PubMed

    Subramanian, Bhargavi; Pagilla, Krishna R

    2015-02-01

    An anaerobic digester (AD) is the most essential step to generate energy in the form of biogas from waste. AD foaming is widespread and leads to deterioration of the AD process and operation. In extreme conditions, AD foaming poses a significant safety risk and considerable economic impacts. It is, therefore, necessary to understand the fundamentals of AD foaming to develop effective strategies that can help minimize the foaming impacts. Several aspects of AD foaming have attracted considerable research attention, however, the focused has been mainly on site specific causes and prevention. Here, the available three-phase foam literature is reviewed with an emphasis on the fundamental aspects of bubble formation in AD: similarities between AD foams and other "desirable" foams, surface rheology, physico-chemical aspects of carbon dioxide (CO2) in digesters, dynamics of the gas-phase, pH, alkalinity and certain relationships between these factors are discussed. All of the abovementioned fundamental aspects seem to be involved in AD foam formation. However, the detailed relationship between these uncontrolled and controlled factors, foam formation and its implications for process and operation of AD is still inconclusive. PMID:25487880

  12. 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

  13. 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...

  14. Comparison of non-agitated and agitated batch, thermophilic anaerobic digestion of sugarbeet tailings.

    PubMed

    Tian, Zhuoli; Chauliac, Diane; Pullammanappallil, Pratap

    2013-02-01

    Sugar beet tailings were anaerobically digested at non-agitated and agitated conditions in identical thermophilic batch reactors. The average methane yield in the agitated digester was only 74% of that in the non-agitated digester. Ninety percent of the ultimate methane yield was produced in approximately 5 days in the non-agitated digester whereas it took 12 days in agitated digester. Even upon using an active inoculum from non-agitated digester the methane rate and yield was low in the agitated digester. On the other hand when the poorly performing inoculum from the agitated digester was transferred to the non-agitated digester, its activity was immediately enhanced. The non-agitated digester harbored a diverse microbial community with phylotypes Methanoculleus and Methanosarcina being dominant methanogens. Methanosaeta was the only methanogen detected in the agitated digester. It also contained a hydrogen-producing bacterial phylotype Petrotoga in high proportion which was not detected in the other digester. PMID:23262019

  15. 78 FR 9401 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-08

    ... Digestive and Kidney Diseases Special Emphasis Panel; R24 Collaborative Interdisciplinary Team Science-3... Digestive and Kidney Diseases Special Emphasis Panel; R24 Collaborative Interdisciplinary Team Science-8... Digestive and Kidney Diseases Special Emphasis Panel; R24 Collaborative Interdisciplinary Team...

  16. 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...

  17. 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 ...

  18. 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...

  19. 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. PMID:22520182

  20. 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 from many sources, both…

  1. 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…

  2. 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 of surveys and…

  3. 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 of American education…

  4. 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…

  5. Recovery of failed solid-state anaerobic digesters.

    PubMed

    Yang, Liangcheng; Ge, Xumeng; Li, Yebo

    2016-08-01

    This study examined the performance of three methods for recovering failed solid-state anaerobic digesters. The 9-L digesters, which were fed with corn stover, failed at a feedstock/inoculum (F/I) ratio of 10 with negligible methane yields. To recover the systems, inoculum was added to bring the F/I ratio to 4. Inoculum was either added to the top of a failed digester, injected into it, or well-mixed with the existing feedstock. Digesters using top-addition and injection methods quickly resumed and achieved peak yields in 10days, while digesters using well-mixed method recovered slowly but showed 50% higher peak yields. Overall, these methods recovered 30-40% methane from failed digesters. The well-mixed method showed the highest methane yield, followed by the injection and top-addition methods. Recovered digesters outperformed digesters had a constant F/I ratio of 4. Slow mass transfer and slow growth of microbes were believed to be the major limiting factors for recovery. PMID:27155759

  6. Impact of sludge thickening on energy recovery from anaerobic digestion.

    PubMed

    Puchajda, B; Oleszkiewicz, J

    2008-01-01

    This paper presents energy balances for various digestion systems, which include single mesophilic digestion, single thermophilic digestion, two-stage thermophilic-mesophilic digestion system and systems at elevated solids content in sludge. On the basis of a sludge flow containing 30 tons TS/day (equivalent to a 100 ML/d WWTP plant) it was shown that a two-stage thermophilic-mesophilic digestion system generated more available energy than single mesophilic digestion and single thermophilic digestion systems. Sludge thickening offered the greatest amount of available energy; however that energy surplus was offset by the cost of thickening. After the cost of thickening was converted into equivalent energy units it was shown that the price of energy is important in calculation of equivalent energy units related to operation of the thickening plant. Sludge thickening may be beneficial from energy view point compared to conventional mesophilic digestion when price of energy exceeds dollars 0.08 CAN kW-hr. PMID:18309218

  7. 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…

  8. Community Colleges: General Information and Resources. ERIC Digest.

    ERIC Educational Resources Information Center

    Foote, Elizabeth

    This digest offers general information about American community colleges and lists a variety of sources of additional information about these institutions. The digest provides the defining characteristics of community colleges and information on their curricula; statistics on enrollments and student characteristics; information on faculty…

  9. 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 of American education…

  10. 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. PMID:20719427

  11. 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…

  12. 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;…

  13. National Institute of Diabetes and Digestive and Kidney Diseases

    MedlinePlus

    ... Topics Information about diabetes, digestive and liver diseases, kidney diseases, weight control and nutrition, urologic diseases, endocrine and ... metabólicas, y enfermedades hematológicas Health Statistics Diabetes, digestive, kidney diseases, obesity, weight and more Healthy Moments Radio Broadcast ...

  14. 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...

  15. 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.…

  16. 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…

  17. 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…

  18. 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...

  19. 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 of surveys and…

  20. 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…

  1. 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…

  2. Addressing Diversity in Special Education Research. ERIC/OSEP Digest.

    ERIC Educational Resources Information Center

    Utley, Cheryl A.; Obiakor, Festus E.

    This digest reviews scientific and methodological problems in special education research related to race, ethnicity, and socioeconomic status. The first section of the digest discusses the various definitions of race, ethnicity, culture, and socioeconomic status. The problems with current race classification and the difficulties in determining the…

  3. Teaching about the U.S. Presidency. ERIC Digest.

    ERIC Educational Resources Information Center

    Drake, Sarah E.; Vontz, Thomas S.

    This ERIC digest addresses (1) the constitutional foundations of the U.S. presidency, (2) how the role of chief executive has changed through the years, and (3) Internet resources for teaching about the U.S. presidency. The digest discusses the Philadelphia Convention (1787), dominant issues guiding the creation of the chief executive's role,…

  4. Electronic Discourse: Evolving Conventions in Online Academic Environments. ERIC Digest.

    ERIC Educational Resources Information Center

    Abdullah, Mardziah Hayati

    Based on the premise that computer networks are changing the way people think and interact, this Digest discusses some features of electronic discourse as a relatively new form of discourse and examines the current research on computer mediated communication text. The Digest suggests further research on how other features of electronic discourse…

  5. Dramatic Activities in Language Arts Classrooms: Resource Summary. ERIC Digest.

    ERIC Educational Resources Information Center

    Tatar, Sibel

    This digest reviews some of the related literature about the benefits of classroom drama activities and introduces a variety of resources to help educators incorporate dramatic activities in their language arts classrooms. The digest notes that although several terms have been used to refer to "classroom drama" such as creative dramatics,…

  6. ERIC Digests, 1988-1991: A Compendium of Forty Titles.

    ERIC Educational Resources Information Center

    ERIC Clearinghouse on Educational Management, Eugene, OR.

    This compendium contains 40 ERIC Digests published by the ERIC Clearinghouse on Educational Management from 1988 to 1991. Listed alphabetically by title, the digests discuss a wide range of topics related to school management and administrative responsibilities, followed by 8 to 15 references. Topics covered include AIDS/HIV education; evaluation…

  7. 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...

  8. 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...

  9. 1 CFR 6.5 - Indexes, digests, and guides.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 1 General Provisions 1 2012-01-01 2012-01-01 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...

  10. 1 CFR 6.5 - Indexes, digests, and guides.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 1 General Provisions 1 2013-01-01 2012-01-01 true 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...

  11. 1 CFR 6.5 - Indexes, digests, and guides.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 1 General Provisions 1 2014-01-01 2012-01-01 true 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...

  12. Restriction digestion method for haplotyping the potato psyllid, Bactericera cockerelli

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A restriction digestion method has been developed for haplotyping the potato psyllid, Bactericera cockerelli Sulc., an economically important pest of solanaceous crops. This method differentiates the four known potato psyllid haplotypes by utilizing restriction enzyme digestion of a portion of the ...

  13. POLIOVIRUS TYPE 1: NEUTRALIZATION BY PAPAIN-DIGESTED ANTIBODIES.

    PubMed

    VOGT, A; KOPP, R; MAASS, G; REICH, L

    1964-09-25

    Papain-digested rabbit antibody (Porter's fractions I and II) can neutralize poliovirus. Neutralizing capacity after digestion ranged from 35 to 45 percent of that of the undigested antibody. No definite dissociation of the antibody fragments from the virus was observed after the reaction mixture had been diluted in a neutral medium. PMID:14175107

  14. Biogas production from anaerobic co-digestion of food waste with dairy manure in a two-phase digestion system.

    PubMed

    Li, Rongping; Chen, Shulin; Li, Xiujiu

    2010-01-01

    Co-digestion of food waste and dairy manure in a two-phase digestion system was conducted in laboratory scale. Four influents of R0, R1, R2, and R3 were tested, which were made by mixing food waste with dairy manure at different ratios of 0:1, 1:1, 3:1, and 6:1, respectively. For each influent, three runs of experiments were performed with the same overall hydraulic retention time (HRT) of 13 days but different HRT for acidification (1, 2, and 3 days) and methanogenesis (12, 11, and 10 days) in two-phase digesters. The results showed that the gas production rate (GPR) of co-digestion of food waste with dairy manure was enhanced by 0.8-5.5 times as compared to the digestion with dairy manure alone. Appropriate HRT for acidification was mainly determined by the biodegradability of the substrate digested. Three-, 2-, and 1-day HRT for acidification were found to be optimal for the digestion of R0, R1, and R2/R3, respectively, when overall HRT of 13 days was used. The highest GPR of 3.97 L/L.day was achieved for R3(6:1) in Run 1 (1 + 12 days), therefore, the mixing ratio of 6:1 and HRT of 1 day for acidification were considered to be the optimal ones and thus recommended for co-digestion of food waste and dairy manure. There were close correlations between degradation of organic matters and GPR. The highest VS removal rate was achieved at the same HRT for acidification and mixing ratio of food waste and dairy manure as GPR in the co-digestion. The two-phase digestion system showed good stability, which was mainly attributed to the strong buffering capacity with two-phase system and the high alkalinity from dairy manure when co-digested with food waste. PMID:19214795

  15. In vitro digestibility and immunoreactivity of bovine milk proteins.

    PubMed

    Do, Andrew B; Williams, Kristina; Toomer, Ondulla T

    2016-01-01

    Current models of digestibility solely utilize pepsin stability to assess the safety of allergenic food proteins. However, in vivo complete protein digestion requires acid denaturation and pepsin, trypsin, and/or chymotrypsin cleavage. This study aimed to identify the immunoreactivity and allergenicity of stable bovine milk proteins, using an improved digestibility model to simulate physiological gastric and intestinal conditions in vitro. Gel electrophoresis and immunoblot analysis were used to determine protein stability and immunoreactivity, respectively. Immunoreactivity of bovine milk proteins, β-lactoglobulin (β-LG) and casein (CN) was greatly diminished with gastric simulation (0-60 min), but some proteins were stable and immunoreactive with simulated intestinal digestive conditions (0-60 min). This study demonstrates the need for improved digestibility models for more accurate assessment of the behavior of food allergens in vivo. PMID:26213013

  16. 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. PMID:21977645

  17. Comparison of methane production by co-digesting fruit and vegetable waste with first stage and second stage anaerobic digester sludge from a two stage digester.

    PubMed

    Park, Nathan D; Thring, Ronald W; Helle, Steve S

    2012-01-01

    Fruit and vegetable waste (FVW) was co-digested with first stage (FSS) and second stage anaerobic digester sludge (SSS) separately, over the course of 10 days, in batch reactors. Addition of FVW significantly increased the methane production in both sludges. After 10 days of digestion FSS + FVW produced 514 ± 57 L CH(4) kg VS(-1)(added) compared with 392 ± 16 L CH(4) for the SSS + FVW. The increased methane yield was most likely due to the higher inoculum substrate ratio of the FSS. The final VS and COD contents of the sewer sludge and FVW mixtures were not significantly different from the control values suggesting that all of the FVW added was degraded within 10 days. It is recommended that FVW be added to the first stage of the anaerobic digester in order to maximize methane generation. PMID:22437023

  18. 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. PMID:26239220

  19. 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…

  20. 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. PMID:24191456

  1. 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. PMID:27279140

  2. 77 FR 29676 - National Institute of Diabetes and Digestive and Kidney Disorders; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-18

    ... Director for Pharmacogenomics and Drug Discovery, National Institute of Diabetes and Digestive and Kidney..., Program Director for Pharmacogenomics and Drug Discovery, National Institute of Diabetes and Digestive...

  3. Anaerobic digestion and co-digestion processes of vegetable and fruit residues: process and microbial ecology.

    PubMed

    Garcia-Peña, E I; Parameswaran, P; Kang, D W; Canul-Chan, M; Krajmalnik-Brown, R

    2011-10-01

    This study evaluated the feasibility of methane production from fruit and vegetable waste (FVW) obtained from the central food distribution market in Mexico City using an anaerobic digestion (AD) process. Batch systems showed that pH control and nitrogen addition had significant effects on biogas production, methane yield, and volatile solids (VS) removal from the FVW (0.42 m(biogas)(3)/kg VS, 50%, and 80%, respectively). Co-digestion of the FVW with meat residues (MR) enhanced the process performance and was also evaluated in a 30 L AD system. When the system reached stable operation, its methane yield was 0.25 (m(3)/kg TS), and the removal of the organic matter measured as the total chemical demand (tCOD) was 65%. The microbial population (general Bacteria and Archaea) in the 30 L system was also determined and characterized and was closely correlated with its potential function in the AD system. PMID:21865034

  4. 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. PMID:27347799

  5. 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.

  6. 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.

  7. 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.

  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 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.

  10. 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.

  11. 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.

  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 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  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 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.

  2. Autogenerative high pressure digestion: anaerobic digestion and biogas upgrading in a single step reactor system.

    PubMed

    Lindeboom, R E F; Fermoso, F G; Weijma, J; Zagt, K; van Lier, J B

    2011-01-01

    Conventional anaerobic digestion is a widely applied technology to produce biogas from organic wastes and residues. The biogas calorific value depends on the CH, content which generally ranges between 55 and 65%. Biogas upgrading to so-called 'green gas', with natural gas quality, generally proceeds with add-on technologies, applicable only for biogas flows > 100 m3/h. In the concept of autogenerative high pressure digestion (AHPD), methanogenic biomass builds up pressure inside the reactor. Since CO2 has a higher solubility than CH4, it will proportion more to the liquid phase at higher pressures. Therefore, AHPD biogas is characterised by a high CH4 content, reaching equilibrium values between 90 and 95% at a pressure of 3-90 bar. In addition, also H2S and NH3 are theoretically more soluble in the bulk liquid than CO2. Moreover, the water content of the already compressed biogas is calculated to have a dew point <--10 degrees C. Ideally, high-quality biogas can be directly used for electricity and heat generation, or injected in a local natural gas distribution net. In the present study, using sodium acetate as substrate and anaerobic granular sludge as inoculum, batch-fed reactors showed a pressure increase up to 90 bars, the maximum allowable value for our used reactors. However, the specific methanogenic activity (SMA) of the sludge decreased on average by 30% compared to digestion at ambient pressure (1 bar). Other results show no effect of pressure exposure on the SMA assessed under atmospheric conditions. These first results show that the proposed AHPD process is a highly promising technology for anaerobic digestion and biogas upgrading in a single step reactor system. PMID:22097043

  3. 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. PMID:19748957

  4. Amine modification of digested peptide at C-terminal end during protein digestion by protease.

    PubMed

    Ito, Toshiyuki; Sugita, Yoshiaki; Takao, Koichi; Ikeguchi, Yoshihiko; Shirahata, Akira

    2007-10-01

    We recently reported that C-terminal polyamine modification occurs when proteins are digested with trypsin in the presence of polyamine [Biochem. Biophys. Res. Commun., 356, 159-162 (2007)]. In the present study, the characteristics of this C-terminal modification in the presence of protease and amine were investigated. When hemoglobin (HB) was digested with trypsin in the presence of N-(2-pyridyl)-1,4-diaminobutane (Py4), formation of the modified peptide was dependent on time and on HB or Py4 concentration. When synthetic peptide was treated with trypsin in the presence of Py4, ca. 0.1% of the peptide was modified with Py4. When HB or cytochrome C was treated with a range of serine proteases in the presence of various amines (Py4, N-(2-pyridyl)-1,3-diaminopropane, tranexamic acid, isonicotinic acid hydrazide and ampicillin), the modified peptide was detected in all cases tested, thus suggesting that amine modification widely accompanies digestion by proteases. PMID:17917247

  5. 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.

  6. Digestion of Protein in Premature and Term Infants.

    PubMed

    Dallas, David C; Underwood, Mark A; Zivkovic, Angela M; German, J Bruce

    2012-04-23

    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

  7. 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. PMID:17571838

  8. [Anaerobic digestion of animal manure contaminated by tetracyclines].

    PubMed

    Tong, Zi-Lin; Liu, Yuan-Lu; Hu, Zhen-Hu; Yuan, Shou-Jun

    2012-03-01

    Anaerobic digestion of pig manure spiked with tetracycline (TC) and chlortetracycline (CTC) and the degradation of the two antibiotics during the anaerobic digestion at 35 degrees C were investigated. The results indicate that propionate was the main volatile fatty acid produced during the anaerobic digestion followed by acetate. Compared with the CTC addition, TC + CTC addition showed obvious inhibitory effect on the hydrolysis and acidification of easily digestible organic components of pig manure. The cumulative methane production of TC, CTC, TC + CTC and CK2 during anaerobic digestion was 386.4 mL, 406.0 mL, 412.1 mL and 464.6 mL, respectively. Degradation of TC and CTC followed the first-order kinetic equation. The half-life of TC and CTC was 14-18 days and 10 days, respectively. After the treatment of 45-day anaerobic digestion, the degradation efficiency of TC was 88.6%-91.6% with 97.7%-98.2% of CTC. Therefore, anaerobic digestion shows the benefit on the management of animal manures contaminated by tetracyclines. PMID:22624404

  9. Kinetics of Cellulose Digestion by Fibrobacter succinogenes S85

    PubMed Central

    Maglione, G.; Russell, J. B.; Wilson, D. B.

    1997-01-01

    Growing cultures of Fibrobacter succinogenes S85 digested cellulose at a rapid rate, but nongrowing cells and cell extracts did not have detectable crystalline cellulase activity. Cells that had been growing exponentially on cellobiose initiated cellulose digestion and succinate production immediately, and cellulose-dependent succinate production could be used as an index of enzyme activity against crystalline cellulose. Cells incubated with cellulose never produced detectable cellobiose, and cells that were preincubated for a short time with thiocellobiose lost their ability to digest cellulose (competitive inhibition [K(infi)] of only 0.2 mg/ml or 0.56 mM). Based on these results, the crystalline cellulases of F. succinogenes were very sensitive to feedback inhibition. Different cellulose sources bound different amounts of Congo red, and the binding capacity was HCl-regenerated cellulose > ball-milled cellulose > Sigmacel > Avicel > filter paper. Congo red binding capacity was highly correlated with the maximum rates of metabolism of cellulose digestion and inversely related to K(infm). Congo red (250 (mu)g/ml) did not inhibit the growth of F. succinogenes S85 on cellobiose, but this concentration of Congo red inhibited the rate of ball-milled cellulose digestion. A Lineweaver-Burk plot of ball-milled cellulose digestion rate versus the amount of cellulose indicated that Congo red was a competitive inhibitor of cellulose digestion (K(infi) was 250 (mu)g/ml). PMID:16535519

  10. 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. PMID:23764598

  11. Digestion kinetics of carbohydrate fractions of citrus by-products

    PubMed Central

    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. PMID:25992250

  12. 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. PMID:25840737

  13. 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. PMID:25919065

  14. 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. PMID:27432729

  15. - 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

  16. 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. PMID:26020739

  17. 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

  18. 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

  19. Digestive cell turnover in digestive gland epithelium of slugs experimentally exposed to a mixture of cadmium and kerosene.

    PubMed

    Zaldibar, B; Cancio, I; Soto, M; Marigómez, I

    2007-11-01

    Slugs, Arion ater (L), have been proposed as sentinel organisms to assess soil health. In slugs under the influence of pollutants, digestive cell loss and the concomitant increase of excretory cells of the digestive gland have been described. The aim of the present work was to determine up to what extent digestive cell loss affects biomarkers and whether the affectation is reversible after exposure to a mixture of metal and organic pollutants. Slugs were dosed with a mixture of cadmium and kerosene in the food for 27 days. Apart from chemical analyses, the volume density of black silver deposits (Vv(BSD)) after autometallography, and acyl-CoA oxidase (AOX) activity were used as biomarkers of exposure to metals and organic compounds, respectively. As effect biomarkers, changes in the volume density of the cell types that constitute the digestive gland epithelium were calculated. Proliferating cells were identified by means of bromodeoxyuridine (BrdU) immunohistochemistry. Results revealed that the mixture of pollutants provoked an increase in Vv(BSD) and AOX activity and a decrease in the number of digestive cells. These changes had no effect in the digestive gland accumulation capacity or in the effect and exposure biomarkers employed. BrdU-labelling showed that exposure to pollutants provoked an enhanced digestive cell proliferation. PMID:17706745

  20. Secondary Structure and Subunit Composition of Soy Protein In Vitro Digested by Pepsin and Its Relation with Digestibility

    PubMed Central

    Yang, Yong; Wang, Zhongjiang; Wang, Rui; Sui, Xiaonan; Qi, Baokun; Han, Feifei; Li, Yang; Jiang, Lianzhou

    2016-01-01

    In the present study, in vitro digestibility and structure of soybean protein isolates (SPIs) prepared from five soybean varieties were investigated in simulated gastric fluid (SGF), using FT-IR microspectroscopy and SDS-PAGE. The result indicated that β-conformations were prone to be hydrolyzed by pepsin preferentially and transformed to unordered structure during in vitro digestion, followed by the digestion of α-helix and unordered structure. A negative linear correlation coefficient was found between the β-conformation contents of five SPIs and their in vitro digestibility values. The intensities of the protein bands corresponding to 7S and 11S fractions were decreased and many peptide bands appeared at 11~15 kDa during enzymatic hydrolysis. β-conglycinin was poorly hydrolyzed with pepsin, especially the β-7S subunit. On the other hand, basic polypeptides of glycinin degraded slower than acidic polypeptides and represented a large proportion of the residual protein after digestion. 11S-A3 of all SPIs disappeared after 1 h digestion. Moreover, a significant negative linear correlation coefficient (r = −0.89) was found between the β-7S contents of five SPIs and their in vitro digestibility values. These results are useful for further studies of the functional properties and bioactive properties of these varieties and laid theoretical foundations for the development of the specific functional soy protein isolate. PMID:27298825

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

    PubMed

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

    2014-10-01

    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 (NH4-N and/or free NH3) can cause process imbalance during the digestion. Mono-digestion of rendering wastes at an organic loading rate (OLR) of 1.5 kg volatile solids (VS)/m(3)d and hydraulic retention time (HRT) of 50 d was unstable and resulted in methane yields of 450 dm(3)/kg VS(fed). On the other hand, co-digestion of rendering wastes with potato pulp (60% wet weight, WW) at the same OLR and HRT improved the process stability and increased methane yields (500-680 dm(3)/kg VS(fed)). Thus, it can be concluded that co-digestion of rendering wastes with potato pulp could improve the process stability and methane yields from these difficult to treat industrial waste materials. PMID:25002371

  2. The digestion of kiwifruit (Actinidia deliciosa) fibre and the effect of kiwifruit on the digestibility of other dietary nutrients.

    PubMed

    Montoya, Carlos A; Saigeman, Stuart; Rutherfurd, Shane M; Moughan, Paul J

    2016-04-15

    The effect of dietary kiwifruit inclusion level on the digestibility of kiwifruit fibre and dietary nutrients was studied. Ileal cannulated pigs (50±1.9 kg) were fed a fibre-free diet for seven days (n=14) followed by kiwifruit-containing diets (133 or 266 g kiwifruit/kg dry matter) (n=7) for 44 days followed by the fibre-free diet (n=14) for seven days. Faecal and ileal samples were collected on days 5, 11, 21, 35, 49 and 56. The soluble kiwifruit fibre was highly digested in the foregut (80%), and the insoluble fibre in the hindgut (95%). Increasing the kiwifruit inclusion level decreased the apparent ileal and faecal digestibilities of several nutrients (P<0.05), including the faecal digestibility of insoluble kiwifruit fibre and led to higher ileal and faecal concentrations of short-chain fatty acids (P<0.05). The decreased digestibility was explained by the lower digestibility of kiwifruit itself. The duration of kiwifruit consumption per se did not affect dietary nutrient digestibility (P>0.05). PMID:26616986

  3. 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. PMID:19151501

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

    PubMed

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

    2014-04-01

    This research was aimed at assessing the fertilizer quality and public health implications of using digestate biofertilizer from the anaerobic digestion of food wastes and human excreta. Twelve (12) kg of food wastes and 3kg of human excreta were mixed with water in a 1:1 w/v to make 30-l slurry that was fed into the anaerobic digester to ferment for 60days at mesophilic temperature (22-31°C). Though BOD, COD, organic carbon and ash content in the feedstock were reduced after anaerobic digestion by 50.0%, 10.6%, 74.3% and 1.5% respectively, nitrogen, pH and total solids however increased by 12.1%, 42.5% and 12.4% respectively. The C/N ratios of the feedstock and compost are 135:1 and 15.8:1. The residual total coliforms of 2.10×10(8)CFU/100ml in the digestate was above tolerable limits for direct application on farmlands. Microbial analysis of the digestate biofertilizer revealed the presence of Pseudomonas, Klebsiella, Clostridium, Bacillus, Bacteroides, Penicillum, Salmollena, and Aspergillus. Klebsiella, Bacillus, Pseudomonas, Penicillum and Aspergillus can boost the efficiency of the biofertilizer through nitrogen fixation and nutrient solubility in soils but Klebsiella again and Salmollena are potential health risks to end users. Further treatment of the digestate for more efficient destruction of pathogens is advised. PMID:24556263

  5. Secondary Structure and Subunit Composition of Soy Protein In Vitro Digested by Pepsin and Its Relation with Digestibility.

    PubMed

    Yang, Yong; Wang, Zhongjiang; Wang, Rui; Sui, Xiaonan; Qi, Baokun; Han, Feifei; Li, Yang; Jiang, Lianzhou

    2016-01-01

    In the present study, in vitro digestibility and structure of soybean protein isolates (SPIs) prepared from five soybean varieties were investigated in simulated gastric fluid (SGF), using FT-IR microspectroscopy and SDS-PAGE. The result indicated that β-conformations were prone to be hydrolyzed by pepsin preferentially and transformed to unordered structure during in vitro digestion, followed by the digestion of α-helix and unordered structure. A negative linear correlation coefficient was found between the β-conformation contents of five SPIs and their in vitro digestibility values. The intensities of the protein bands corresponding to 7S and 11S fractions were decreased and many peptide bands appeared at 11~15 kDa during enzymatic hydrolysis. β-conglycinin was poorly hydrolyzed with pepsin, especially the β-7S subunit. On the other hand, basic polypeptides of glycinin degraded slower than acidic polypeptides and represented a large proportion of the residual protein after digestion. 11S-A3 of all SPIs disappeared after 1 h digestion. Moreover, a significant negative linear correlation coefficient (r = -0.89) was found between the β-7S contents of five SPIs and their in vitro digestibility values. These results are useful for further studies of the functional properties and bioactive properties of these varieties and laid theoretical foundations for the development of the specific functional soy protein isolate. PMID:27298825

  6. 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. PMID:25353947

  7. [Endoscopic ultrasonography of the upper digestive tract].

    PubMed

    Mesihović, Rusmir; Vanis, Nenad; Tanović, Haris; Gornjaković, Srdan; Smajlović, Fahrudin; Borovac, Nada

    2003-01-01

    Endoscopic Ultrasonography, or EUS, has joined medical techniques of endoscopy with high frequency ultrasound technique, known as ultrasound. This removable achievement allows physician for microscopic tissue examination, not only in digestive system, but also in its surroundings by highly frequent technique. Endoscopic ultrasonography detects all kinds and nature of possible abnormalities, including and information, which are necessary for proper diagnosis and optimal treatment. In experience hands, EUS can detect abnormalities, which are undetectable during any other techniques of examination. EUS is applied from inside the body, near or even touching the examined surface, so the precise, highly frequent energy of showing the images can be used. The sonography, MRI, CT techniques must show the inner organs through outside surface of body, loosing the resolution during process. The superior resolution of EUS shows 5 layers of digestive tract, almost equally good as by microscope; none of other techniques allows showing of intestinal wall equally good as this one. By EUS liquid has been proved with 90% of precision in diagnosis of operative degrees of pancreas tumours. CT in this case has shows only 50% of precision. Highly skilled surgeons are aware of application of these diagnostics techniques in preoperative cases so the surgical removement of tumours is going to be more effective. The precision of EUS findings are of critical importance for the utilisation of maximum of new treatment having in mind that abnormalities could be diagnosed and characterised without operative intervention. To be able to focus on specific anatomic surfaces, there is need of great knowledge, skillfulness and praxis during the manipulation with EUS instrument. The years of experience are needed to be able to achieve high standard of expertise. The accuracy of results varies, depending on physicians diagnostic experience, sub-optimal results are not going to be a good guide during

  8. Sonochemical Digestion of Soil and Sediment Samples

    SciTech Connect

    Sinkov, Sergei I.; Lumetta, Gregg J.

    2006-10-12

    This work was performed as part of a broader effort to automate analytical methods for determination of plutonium and other radioisotopes in environmental samples. The work described here represented a screening study to determine the potential for applying ultrasonic irradiation to sample digestion. Two standard reference materials (SRMs) were used in this study: Columbia River Sediment and Rocky Flats Soil. The key experiments performed are listed below along with a summary of the results. The action of nitric acid, regardless of its concentration and liquid-to-solid ratio, did not achieve dissolution efficiency better that 20%. The major fraction of natural organic matter (NOM) remained undissolved by this treatment. Sonication did not result in improved dissolution for the SRMs tested. The action of hydrofluoric acid at concentrations of 8 M and higher achieved much more pronounced dissolution (up to 97% dissolved for the Rocky Flats soil sample and up to 78% dissolved for the Columbia River Sediment sample). Dissolution efficiency remains constant for solid-to-liquid ratios of up to 0.05 to 1 and decreases for the higher loadings of the solid phase. Sonication produced no measurable effect in improving the dissolution of the samples compared with the control digestion experiments. Combined treatment of the SRM by mixtures of HNO3 and HF showed inferior performance compared with the HF alone. An adverse effect of sonication was found for the Rocky Flats soil material, which became more noticeable at higher HF concentrations. Sonication of the Columbia River sediment samples had no positive effect in the mixed acid treatment. The results indicate that applying ultrasound in an isolated cup horn configuration does not offer any advantage over conventional ''heat and mix'' treatment for dissolution of the soil and sediment based on the SRM examined here. This conclusion, however, is based on an approach that uses gravimetric analysis to determine gross dissolution

  9. 40 CFR 428.80 - Applicability; description of the wet digestion reclaimed rubber subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... digestion reclaimed rubber subcategory. 428.80 Section 428.80 Protection of Environment ENVIRONMENTAL... Wet Digestion Reclaimed Rubber Subcategory § 428.80 Applicability; description of the wet digestion... discharges resulting from the production of reclaimed rubber by use of the wet digestion process....

  10. Historical Analysis of Portuguese Primary School Textbooks (1920-2005) on the Topic of Digestion

    ERIC Educational Resources Information Center

    Carvalho, Graca S.; Silva, Rui; Clement, Pierre

    2007-01-01

    Our previous studies have shown that Portuguese primary school pupils and teachers have three main difficulties in the representation of the digestion process: the sequence of the digestive tract, blood absorption, and the relationship of the digestive function with other human functions. In this study we analysed the topic of digestion in 63…

  11. 40 CFR 428.80 - Applicability; description of the wet digestion reclaimed rubber subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... digestion reclaimed rubber subcategory. 428.80 Section 428.80 Protection of Environment ENVIRONMENTAL... Wet Digestion Reclaimed Rubber Subcategory § 428.80 Applicability; description of the wet digestion... discharges resulting from the production of reclaimed rubber by use of the wet digestion process....

  12. Anaerobic Digestion I. Sludge Treatment and Disposal Course #166. Instructor's Guide [and] Student Workbook.

    ERIC Educational Resources Information Center

    Arasmith, E. E.

    This lesson is the first of a two-part series on anaerobic digestion. Topics discussed include the five basic functions of an anaerobic digester, basic theory of the biological processes involved, basic equipment necessary for digestion, and the products of digestion. The lesson includes an instructor's guide and student workbook. The instructor's…

  13. Digestibility of rice (Oryza sativa L.) flours and starches differing in amylose content

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Digestibility of starches in four rice samples with amylose content (AC) from 1.7 to 55.4%, including a newly developed high-amylose rice, was investigated. An in vitro enzymatic starch digestion method an an AOAC method were applied to correlate rapidly digestible starch (RDS), slowly digestible s...

  14. Two-stage upflow anaerobic digestion of concentrated sludge

    SciTech Connect

    Ghosh, S.; Sajjad, A.; Henry, M.P.; Bleakney, R.A.

    1983-01-01

    The development of an innovative fermentation mode and the application of novel upflow reactors for biogasification of high-solids-content sludges are described; anaerobic digestion is conducted at higher loading rates and lower hydraulic residence times (HRT's) to obtain higher methane yields and production rates and better effluent qualities than those of conventional single-stage continuously stirred tank reactor digesters. Digestion of primary sludge in a two-phase upflow system at a 5.6-day HRT (1.2 days for stage 1 and 4.4 days for stage 2) exhibited a methane yield of 6.8 supercritical fluid/lb volatile solids added, which was significantly higher than those from conventional digestion at much higher HRT's. 27 references, 7 figures, 6 tables.

  15. Role of microRNA-7 in digestive system malignancy

    PubMed Central

    Chen, Wan-Qun; Hu, Ling; Chen, Geng-Xin; Deng, Hai-Xia

    2016-01-01

    There are several malignancies of the digestive system (including gastric, pancreatic and colorectal cancers, and hepatocellular carcinoma), which are the most common types of cancer and a major cause of death worldwide. MicroRNA (miR)-7 is abundant in the pancreas, playing an important role in pancreatic development and endocrine function. Expression of miR-7 is downregulated in digestive system malignancies compared with normal tissue. Although there are contrasting results for miR-7 expression, almost all research reveals that miR-7 is a tumor suppressor, by targeting various genes in specific pathways. Moreover, miR-7 can target different genes simultaneously in different malignancies of the digestive system. By acting on many cytokines, miR-7 is also involved in many gastrointestinal inflammatory diseases as a significant carcinogenic factor. Consequently, miR-7 might be a biomarker or therapeutic target gene in digestive system malignancies. PMID:26798443

  16. Energy Integrated Dairy Farm digester and cogeneration system installation

    SciTech Connect

    Ross, C.C.; Walsh, J.L.

    1984-01-01

    Georgia Tech finished in December, 1983 Phase II (system installation and startup) of its four year Energy Integrated Dairy Farm System (EIDFS) program. This paper outlines the selection and installation of the anaerobic digestion and cogeneration components of the EIDFS.

  17. Rheological characterization of digested sludge by solid sphere impact.

    PubMed

    Jiang, Jiankai; Wu, Jing; Poncin, Souhila; Li, Huai Z

    2016-10-01

    An impact method was applied to investigate the rheological characteristics of digested sludge and reveal its transient dynamics. A high-speed camera allowed visualizing the dynamic impact process and observing interaction between impacting sphere and targeted sludge. A damping oscillation was observed after the impact. The crater diameter followed an exponential function, while the crater depth varied as a logarithmic function of both sphere diameter and free fall height. Furthermore, the viscosity and elasticity of digested sludge were evaluated by establishing a simplified impact drag force model. The impact elastic modulus was consistent with the Young's modulus measured by a penetrometer. The impact viscosity was reasonable as the estimated impact shear stress was greater than the yield stress of digested sludge resulting in the formation of crater. The impact method offers an alternative way to reveal the viscoelasticity of digested sludge through a dynamic process. PMID:27372010

  18. 4. OVERALL VIEW OF FACTORY COMPLEX, WITH DIGESTER HOUSE IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. OVERALL VIEW OF FACTORY COMPLEX, WITH DIGESTER HOUSE IN LEFT FOREGROUND. VIEW TO NORTHWEST. - Commercial & Industrial Buildings, Maizewood Insulation Company Factory, 275 Salina Street, Dubuque, Dubuque County, IA

  19. 5. OVERALL VIEW OF FACTORY COMPLEX, WITH DIGESTER HOUSE IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. OVERALL VIEW OF FACTORY COMPLEX, WITH DIGESTER HOUSE IN LEFT FOREGROUND. VIEW TO NORTHWEST. - Commercial & Industrial Buildings, Maizewood Insulation Company Factory, 275 Salina Street, Dubuque, Dubuque County, IA

  20. Bile acid nuclear receptor FXR and digestive system diseases

    PubMed Central

    Ding, Lili; Yang, Li; Wang, Zhengtao; Huang, Wendong

    2015-01-01

    Bile acids (BAs) are not only digestive surfactants but also important cell signaling molecules, which stimulate several signaling pathways to regulate some important biological processes. The bile-acid-activated nuclear receptor, farnesoid X receptor (FXR), plays a pivotal role in regulating bile acid, lipid and glucose homeostasis as well as in regulating the inflammatory responses, barrier function and prevention of bacterial translocation in the intestinal tract. As expected, FXR is involved in the pathophysiology of a wide range of diseases of gastrointestinal tract, including inflammatory bowel disease, colorectal cancer and type 2 diabetes. In this review, we discuss current knowledge of the roles of FXR in physiology of the digestive system and the related diseases. Better understanding of the roles of FXR in digestive system will accelerate the development of FXR ligands/modulators for the treatment of digestive system diseases. PMID:26579439

  1. Degradation of blood in the human digestive tract

    NASA Astrophysics Data System (ADS)

    Mørup, Steen; Johansen, Claus

    1986-02-01

    Samples of human faeces from patients suffering from intestinal bleeding have been studied by use of Mössbauer spectroscopy. It is shown that it is possible to follow the degradation of blood in the digestive tract.

  2. Defining Anaerobic Digestion Stability-Full Scale Study

    NASA Astrophysics Data System (ADS)

    Demitry, M. E., Sr.

    2014-12-01

    A full-scale anaerobic digester receiving a mixture of primary and secondary sludge was monitored for one hundred days. A chemical oxygen demand, COD, and a volatile solids, VS, mass balance was conducted to evaluate the stability of the digester and its capability of producing methane gas. The COD mass balance could account for nearly 90% of the methane gas produced while the VS mass balance showed that 91% of the organic matter removed resulted in biogas formation. Other parameters monitored included: pH, alkalinity, VFA, and propionic acid. The values of these parameters showed that steady state had occurred. Finally, at mesophilic temperature and at steady state performance, the anaerobic digester stability was defined as a constant ratio of methane produced per substrate of ΔVS (average ratio=0.404 l/g). This ratio can be used as universal metric to determine the anaerobic digester stability in an easy and inexpensive way.

  3. Eating and digesting "Lestrygonians": a physiological model of reading.

    PubMed

    Yared, Aida

    2008-01-01

    In this article, I propose that, beneath a deceptively simple story-line, "Lestrygonians" functions like a living entity, one through which Bloom unknowingly traverses. First, there is Joyce's familiar Dublin, on a macroscopic level, and, second, there is the episode's narrative, personified by a gigantic female organism, in whose digestive tract Bloom has been reduced to Lilliputian size. Some critics have noted the importance of the physiological details of digestion here; no one, however, has noted to what extent the structure of the episode is represented by the digestive model. My final claim about the episode's digestive proclivities concerns its effects on the reader. If "Lestrygonians" replicates alimentary functions by propelling both its characters and the reading process along, it also elicits, in the reader, the synesthesia of reading with autonomic sensations. PMID:20836271

  4. Children with Communication Disorders. ERIC Digest #E470 (Revised #419).

    ERIC Educational Resources Information Center

    Council for Exceptional Children, Reston, VA.

    This digest defines the term "communication disorders," states prevalence rates for the condition, describes characteristics of children with communication disorders, and outlines educational implications. Thirteen publications on communication disorders and six organizational resources are listed. (JDD)

  5. Exploring Turkish upper primary level pupils' understanding of digestion

    NASA Astrophysics Data System (ADS)

    Cakici, Yilmaz

    2005-01-01

    This article reports a study of Turkish children's understanding of digestion in Grades 4 and 5 (ages 10-11). Data collection was carried out through the use of an open-ended questionnaire administered to 283 children in three Turkish primary schools. Follow-up interviews were conducted with 30 children in Grade 4 and 72 children in Grade 5. The most significant finding was the children's conception of the digestive process as 'melting of foods' rather than 'breaking foods down'. Some other children considered digestion to be a filtering process that is performed by the stomach in order to separate the useful and waste parts of food. These views 'melting of foods' and 'filtering of foods' have not been mentioned in the literature previously. The study revealed that social influences and everyday language had an important impact on children's learning of the digestive process.

  6. Educating the Consumer about Advertising: Some Issues. ERIC Digest.

    ERIC Educational Resources Information Center

    Gottlieb, Stephen S.

    Providing a basic overview of issues related to advertising and the consumer, this digest discusses the omnipresence of advertisements, suggesting ways for consumers to recognize advertising appeals. Deceptive advertising is discussed, with particular attention paid to financial advertising. (RS)

  7. Anaerobic digestion of livestock manures: A current opportunities casebook

    SciTech Connect

    Lusk, P.D.

    1995-08-01

    Growth and concentration of the livestock industry creates new opportunities for proper disposal of the large quantities of manures generated at dairy, swine, and poultry farms. One manure management system provides not only pollution prevention but also converts a problem into a new profit center. Economic evaluations and case studies of operating systems indicate that the anaerobic digestion of livestock manures is a commercially-available bioconversion technology with considerable potential for providing profitable co-products, including a renewable fuel. An introduction to the engineering economies of these technologies is provided, based on estimates of digesters that generate electricity from the recovered methane. Regression models used to estimate digester cost and internal rate of return are developed from the evaluations. Case studies of operating digesters, including project and maintenance histories, and the operator`s {open_quotes}lessons learned{close_quotes}, are provided as a reality check.

  8. Waste heat utilization in an anaerobic digestion system

    NASA Astrophysics Data System (ADS)

    Boissevain, Brett

    Anaerobic digestion has great potential as an energy source. Not only does it provide an effective method for waste mitigation, but it has the potential to generate significant quantities of fuel and electricity. In order to ensure efficient digestion and biomass utilization, however, the system must be continuously maintained at elevated temperatures. It is technically feasible to supplement such a system with outside energy, but it is more cost effective to heat the system using only the produced biogas. While there is considerable literature covering the theory of anaerobic digestion, there are very few practical studies to show how heat utilization affects system operation. This study considers the effect of major design variables (i.e. heat exchanger efficiencies and biogas conditioning) on promoting a completely self-sustaining digestion system. The thesis considers a real world system and analyzes how it can be improved to avoid the need of an external energy source.

  9. Bile acid nuclear receptor FXR and digestive system diseases.

    PubMed

    Ding, Lili; Yang, Li; Wang, Zhengtao; Huang, Wendong

    2015-03-01

    Bile acids (BAs) are not only digestive surfactants but also important cell signaling molecules, which stimulate several signaling pathways to regulate some important biological processes. The bile-acid-activated nuclear receptor, farnesoid X receptor (FXR), plays a pivotal role in regulating bile acid, lipid and glucose homeostasis as well as in regulating the inflammatory responses, barrier function and prevention of bacterial translocation in the intestinal tract. As expected, FXR is involved in the pathophysiology of a wide range of diseases of gastrointestinal tract, including inflammatory bowel disease, colorectal cancer and type 2 diabetes. In this review, we discuss current knowledge of the roles of FXR in physiology of the digestive system and the related diseases. Better understanding of the roles of FXR in digestive system will accelerate the development of FXR ligands/modulators for the treatment of digestive system diseases. PMID:26579439

  10. Subclinical zinc deficiency impairs pancreatic digestive enzyme activity and digestive capacity of weaned piglets.

    PubMed

    Brugger, Daniel; Windisch, Wilhelm M

    2016-08-01

    This study investigated the effects of short-term subclinical Zn deficiency on exocrine pancreatic activity and changes in digestive capacity. A total of forty-eight weaned piglets were fed ad libitum a basal diet (maize and soyabean meal) with adequate Zn supply (88 mg Zn/kg diet) during a 2-week acclimatisation phase. Animals were then assigned to eight dietary treatment groups (n 6) according to a complete randomised block design considering litter, live weight and sex. All pigs were fed restrictively (450 g diet/d) the basal diet but with varying ZnSO4.7H2O additions, resulting in 28·1, 33·6, 38·8, 42·7, 47·5, 58·2, 67·8 and 88·0 mg Zn/kg diet for a total experimental period of 8 d. Pancreatic Zn concentrations and pancreatic activities of trypsin, chymotrypsin, carboxypeptidase A and B, elastase and α-amylase exhibited a broken-line response to stepwise reduction in dietary Zn by declining beneath thresholds of 39·0, 58·0, 58·0, 41·2, 47·5, 57·7 and 58·0 mg Zn/kg diet, respectively. Furthermore, carboxypeptidase B and α-amylase activities were significantly lower in samples with reduced pancreatic Zn contents. Coefficients of faecal digestibility of DM, crude protein, total lipids and crude ash responded similarly to pancreatic enzyme activities by declining below dietary thresholds of 54·7, 45·0, 46·9 and 58·2 mg Zn/kg diet, respectively. In conclusion, (1) subclinical Zn deficiency impaired pancreatic exocrine enzymes, (2) this response was connected to pancreatic Zn metabolism and (3) the decline in catalytic activity impaired faecal digestibility already after 1 week of insufficient alimentary Zn supply and very early before clinical deficiency symptoms arise. PMID:27230230

  11. Anaerobic digestion of glycerol and co-digestion of glycerol and pig manure.

    PubMed

    Nuchdang, Sasikarn; Phalakornkule, Chantaraporn

    2012-06-30

    The potential of glycerol obtained from transesterification of waste cooking oil as a main carbon source for biogas production was investigated. The glycerol was highly contaminated with oils and fats and was pretreated with sulfuric acid. Using a carbon source of glucose as a control, we compared biogas production from the acid-treated glycerol in a synthetic medium and the acid-treated glycerol mixed with pig manure. The anaerobic digestion of acid-treated glycerol with supplement in a synthetic medium was found to be satisfactory at organic loading rates (OLR) between 1.3, 1.6 and 2.6 g chemical oxygen demand (COD) L(-1) d(-1). The maximum methane yield of 0.32 L at Standard temperature and pressure (STP) g(-1) COD removal was achieved at an OLR of 1.6 g COD L(-1) d(-1) and the methane content was 54% on an average. At a higher organic loading rate of 5.4 g COD L(-1) d(-1), the propionic acid to acetic acid ratio was higher than the critical threshold limit for metabolic imbalance. Anaerobic digestion of acid-treated glycerol with pig manure was also investigated at the COD ratio of 80:20 (glycerol:pig manure). The anaerobic digestion of acid-treated glycerol with pig manure was found to be satisfactory at organic loading rates between 1.3, 1.7, 2.9 and 5.0 g COD L(-1) d(-1) in terms of COD reduction (>80%) and methane content of (62% on an average). However, the biogas production rate was found to significantly decrease at the highest load. The maximum methane yield of 0.24 L STP g(-1) COD removal was achieved at an OLR of 1.3 g COD L(-1) d(-1). PMID:22417895

  12. Digestive neuroendocrine neoplasms: A 2016 overview.

    PubMed

    Merola, Elettra; Rinzivillo, Maria; Cicchese, Noemi; Capurso, Gabriele; Panzuto, Francesco; Delle Fave, Gianfranco

    2016-08-01

    Digestive neuroendocrine neoplasms (DNENs) have an incidence of 2.39 per 100,000 inhabitants per year, and a prevalence of 35 cases per 100,000; the gap between these rates is to be referred to the relatively long survival that characterizes the majority of these tumors, which can be thus considered as chronic oncological diseases. Up to 80% of patients are stage IV since the first diagnosis, presenting a 5-yr overall survival rate of 35%-55% and a twice higher mortality than limited disease. DNENs express somatostatin receptors in more than 80% of cases, detected through immunohistochemistry or functional imaging tests (FITs). This feature identifies patients who may benefit from "cold" somatostatin analogs (SSAs) or peptide receptors radionuclide therapy, although SSAs are sometimes used also with a negative uptake at FITs. The therapeutic options have been recently increased after the identification of molecular pathways involved in DNENs pathogenesis, and the subsequent use of targeted therapies (i.e., Everolimus and Sunitinib) for these neoplasms. This review offers an overview about pancreatic and small bowel NENs, critically underlining the issues that still need to be clarified and the future perspectives to be investigated. PMID:27212431

  13. Screening of 18 species for digestate phytodepuration.

    PubMed

    Pavan, Francesca; Breschigliaro, Simone; Borin, Maurizio

    2015-02-01

    This experiment assesses the aptitude of 18 species in treating the digestate liquid fraction (DLF) in a floating wetland treatment system. The pilot system was created in NE Italy in 2010 and consists of a surface-flow system with 180 floating elements (Tech-IA®) vegetated with ten halophytes and eight other wetland species. The species were transplanted in July 2011 in basins filled with different proportions of DLF/water (DLF/w); periodic increasing of the DLF/w ratio was imposed after transplanting, reaching the worst conditions for plants in summer 2012 (highest EC value 7.3 mS cm/L and NH4-N content 225 mg/L). It emerged that only Cynodon dactylon, Typha latifolia, Elytrigia atherica, Halimione portulacoides, Salicornia fruticosa, Artemisia caerulescens, Spartina maritima and Puccinellia palustris were able to survive under the system conditions. Halophytes showed higher dry matter production than other plants. The best root development (up to 40-cm depth) was recorded for Calamagrostis epigejos, Phragmites australis, T. latifolia and Juncus maritimus. The highest nitrogen (10-15 g/m(2)) and phosphorus (1-4 g/m(2)) uptakes were obtained with P. palustris, Iris pseudacorus and Aster tripolium. In conclusion, two halophytes, P. palustris and E. atherica, present the highest potential to be used to treat DLF in floating wetlands. PMID:25005162

  14. USSR Space Life Sciences Digest, issue 9

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran; Radtke, Mike; Teeter, Ronald; Rowe, Joseph E.

    1987-01-01

    This is the ninth issue of NASA's USSR Space Lifes Sciences Digest. It contains abstracts of 46 papers recently published in Russian language periodicals and bound collections and of a new Soviet monograph. Selected abstracts are illustrated with figures and tables from the original. Additional features include reviews of a Russian book on biological rhythms and a description of the papers presented at a conference on space biology and medicine. A special feature describes two paradigms frequently cited in Soviet space life sciences literature. Information about English translations of Soviet materials available to readers is provided. The abstracts included in this issue have been identified as relevant to 28 areas of aerospace medicine and space biology. These areas are: adaptation, biological rhythms, body fluids, botany, cardiovascular and respiratory systems, developmental biology, endocrinology, enzymology, equipment and instrumentation, gastrointestinal system, genetics, habitability and environment effects, hematology, human performance, immunology, life support systems, mathematical modeling, metabolism, microbiology, morphology and cytology, musculoskeletal system, nutrition, neurophysiology, operational medicine, perception, personnel selection, psychology, radiobiology, and space biology and medicine.

  15. USSR Space Life Sciences Digest, issue 8

    NASA Technical Reports Server (NTRS)

    Hooke, L. R. (Editor); Teeter, R. (Editor); Teeter, R. (Editor); Teeter, R. (Editor); Teeter, R. (Editor); Teeter, R. (Editor)

    1985-01-01

    This is the eighth issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 48 papers recently published in Russian language periodicals and bound collections and of 10 new Soviet monographs. Selected abstracts are illustrated with figures and tables. Additional features include reviews of two Russian books on radiobiology and a description of the latest meeting of an international working group on remote sensing of the Earth. Information about English translations of Soviet materials available to readers is provided. The topics covered in this issue have been identified as relevant to 33 areas of aerospace medicine and space biology. These areas are: adaptation, biological rhythms, biospherics, body fluids, botany, cardiovascular and respiratory systems, cosmonaut training, cytology, endocrinology, enzymology, equipment and instrumentation, exobiology, gastrointestinal system, genetics, group dynamics, habitability and environment effects, hematology, human performance, immunology, life support systems, man-machine systems, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, operational medicine, personnel selection, psychology, reproductive biology, and space biology and medicine.

  16. [The aneurysms of digestive system arteries: three cases].

    PubMed

    Tijani, Y; Chtata, H; Elkaoui, H; Hatim, A; Drissi, M; Abissegue, Y; Taberkant, M

    2015-04-01

    The aneurysms of digestive arteries are a rare pathological entity, with a risk of rupture associated to a high mortality rate, often asymptomatic, then they are discovered incidentally during a exam for other diagnostic purposes. We report three cases of digestive aneurysms, one of celiac trunk, one of mesenteric artery on behçet disease, and one of splenic artery, which were treated surgically with success. PMID:24856656

  17. Chemical digestion of low level nuclear solid waste material

    DOEpatents

    Cooley, Carl R.; Lerch, Ronald E.

    1976-01-01

    A chemical digestion for treatment of low level combustible nuclear solid waste material is provided and comprises reacting the solid waste material with concentrated sulfuric acid at a temperature within the range of 230.degree.-300.degree.C and simultaneously and/or thereafter contacting the reacting mixture with concentrated nitric acid or nitrogen dioxide. In a special embodiment spent ion exchange resins are converted by this chemical digestion to noncombustible gases and a low volume noncombustible residue.

  18. Removal of fecal coliforms by thermophilic anaerobic digestion processes.

    PubMed

    De León, C; Jenkins, D

    2002-01-01

    Recent U.S. EPA regulations (40 CFR Section 503) specify maximum concentrations of pathogens and metals for Class A wastewater treatment plant sludges. The most common sludge process is mesophilic (35 degrees C) digestion which stabilizes the solids, produces a combustible gas but does not create an effluent that meets the 503 Class A pathogen requirements. This investigation was conducted to determine whether anaerobic digestion processes incorporating a thermophilic stage could achieve 503 Class A pathogen levels. The research reported here was a bench-scale screening study meant to identify the most promising process alternatives for further investigation. Fecal Coliform (FC) concentrations were used to assess disinfection efficiency. Digesters were 30 L capacity fed semi-continuously in draw-fill mode. Digester startup was rapid to produce true thermophiles. Temperature staging and pH were assessed in 3 sets of experiments: Set 1 were one stage ("acid phase"), Set 2 were one stage ("acid + methane phases") and Set 3 were two stage ("acid phase" then "methanogenic phase"). Feed was a 1:1 mixture of Thickened Waste Activated Sludge and Primary Sludge. The following anaerobic digestion configurations and operating parameters allowed the production of digested sludge with a mean FC concentration statistically less than 10(3) (the regulatory value for Class A sludge): thermophilic single stage acid phase at 52 and 62 degrees C; thermophilic single stage acid + methane phase at 48 degrees C, 52 degrees C and 62 degrees C; two-stage mesophilic acid phase followed by mesophilic methane phase; two stage mesophilic acid phase followed by thermophilic methane phase at 48 degrees C, 52 degrees C and 62 degrees C. If the maximum digested FC concentration must be below 10(3) MPN/g TS then the following digester configurations and operating conditions will be compliant: two stage mesophilic acid phase followed by thermophilic methane phase at 52 degrees C and 62 degrees C

  19. Phosphorus digestibility and phytate degradation by yearlings and mature horses.

    PubMed

    Fowler, A L; Hansen, T L; Strasinger, L A; Harlow, B E; Lawrence, L M

    2015-12-01

    Inorganic P is often added to growing horse diets because organic P, or phytate-P, is believed to have lower digestibility. If horses can efficiently digest organic P, then the need for inorganic P may be reduced. Much of the P in grain-based concentrates fed to growing horses is in the form of phytate-P. Little is known about the ability of growing horses to degrade phytate-P or whether horse age affects mineral digestion in horses. The objective of this study was to examine the effect of age on P, Ca, and Mg digestibility as well as phytate-P degradation. Four yearling geldings and 4 mature geldings were fed a diet of alfalfa cubes, timothy cubes, and a pelleted concentrate. The diet contained 0.28% total P and 17.4% of that P was in the phytate form. There was a 14-d diet adaptation period followed by a 4-d fecal collection period. Apparent total tract P digestibility was higher for yearlings than mature geldings ( = 0.036; 7.7 and -6.6% for yearlings and mature geldings, respectively). Phytate-P disappearance was 94.8% and did not differ between ages ( = 0.190). Apparent Ca digestibility was lower in mature geldings ( = 0.043), but apparent Mg digestibility did not differ between ages ( = 0.414). Phytate is broken down in the gastrointestinal tract, but the low P digestibilities suggest that either degradation occurs after the site of P absorption or liberated P is recycled back into the gastrointestinal tract. Yearlings can utilize organic P as well as mature horses; therefore, diets without inorganic P are acceptable for growing horses. PMID:26641183

  20. Single stage anaerobic digester at Tarleton State University. Final report

    SciTech Connect

    Not Available

    1980-01-01

    The design and operation of the demonstration plant facilities at Tarleton State University to produce methane in a single stage anaerobic digester are described. A combination of manures from hogs and poultry are used as feedstock. Uses for the methane, cost of the digester, and value of the energy produced are discussed. During the 21 months of operation, 310 people have visited the project. (DMC)

  1. Fast On–Line Digestion System for Protein Characterization

    PubMed Central

    López-Ferrer, Daniel; Petritis, Konstantinos; Lourette, Natacha M.; Clowers, Brian; Hixson, Kim K.; Heibeck, Tyler; Prior, David C; Pasa-Tolić, Ljiljana; Camp, David G.; Belov, Mikhail E.; Smith, Richard D.

    2009-01-01

    An efficient on-line digestion system that reduces the number of sample manipulation steps has been demonstrated for high throughput proteomics. By incorporating a pressurized sample loop into a liquid chromatography-based separation system, both sample and enzyme (e.g., trypsin) can be simultaneously introduced to produce a complete, yet rapid digestion. Both standard proteins and a complex Shewanella oneidensis global protein extract were digested and analyzed using the automated on-line pressurized digestion system coupled to an ion mobility time of flight mass spectrometer and/or an ion trap mass spectrometer. The system denatured, digested, and separated product peptides in a manner of minutes, making it amenable to high-throughput applications. In addition to simplifying and expediting sample processing, the system was easy to implement and no cross contamination was observed among samples. As a result, the on-line digestion system offers a powerful approach for high-throughput screening of proteins that could prove valuable in biochemical research; for example, quick screening of protein-based drugs. PMID:19551971

  2. Study of Resource Recovery and Epidemiology in an Anaerobic Digester

    NASA Technical Reports Server (NTRS)

    Li, K. Y.; Cao, Song; Hunt, M. D.; Fu, Xuping

    1995-01-01

    Three 4-liter packed bed anaerobic digesters were fabricated and operated at 35 degrees C, pH around 7, and hydraulic retention time (HRT) of 20, 10 and 5 days to study the resource recovery and epidemiology in a controlled ecological life support system (CELSS). A simulated wastewater, consisted of shower water, clothwash water, dishwasher water, handwash water, and urine flush water was used as the feeding solution. Under steady-state operation, chemical oxygen demand (COD), total organic carbon (TOC), pH, nitrogen, phosphorus, and potassium wer monitored in the digester input and output solutions. The volume and the CH4/CO2 ratios in the biogas produced from the anaerobic digesters were measured. The results indicate about 90 percent of TOC is converted while only 5-8 percent of N-P-K are consumed in the digester. A multi-drug resistant strain of Salmonella choleraesuis was used as the indicator bacterium in the epidemiology study. The levels of Salmonella choleraesuis in the influent and the effluent wer determined and decimal decay rate constants, k(d), were estimated. The k(d) values were greater at higher initial doses than lower doses for the same HR, and greater for batch digestion (7.89/d) than for continuous digestion (4.28, 3.82, and 3.82/d for 20, 10, and 5 d HRT, respectively).

  3. An integrated photocatalytic microfluidic platform enabling total phosphorus digestion

    NASA Astrophysics Data System (ADS)

    Tong, Jianhua; Dong, Tian; Bian, Chao; Wang, Minrui; Wang, Fangfang; Bai, Yin; Xia, Shanhong

    2015-02-01

    This paper presents an integrated thermally assisted photocatalytic microfluidic chip and its application to the digestion of total phosphorus (TP) in freshwater. A micro heater, a micro temperature sensor, thermal-isolation channels and a polymethylsiloxane (PDMS) reaction chamber were fabricated on the microfluidic chip. Nano-TiO2 film sputtered on the surface of silicon in the reaction area was used as the photocatalyst, and a micro ultraviolet A-ray-light-emitting diode (UVA-LED) array fabricated by MEMS technology were attached to the top of reaction chamber for TP degradation. In this study, sodium tripolyphosphate (Na5P3O10) and sodium glycerophosphate (C3H7Na2O6P) were chosen as the typical components of TP, and these water samples were digested under UVA light irradiation and heating at the same time. Compared with the conventional high-temperature TP digestion which works at 120 °C for 30 min, the thermally assisted UVA digestion method could work at relatively low temperature, and the power consumption is decreased to less than 2 W. Since this digestion method could work without an oxidizing reagent, it is compatible with the electrochemical detection process, which makes it possible to achieve a fully functional detection chip by integrating the digestion unit and electrochemical microelectrode, to realize the on-chip detection of TP, and other water quality parameters such as total nitrogen and chemical oxygen demand.

  4. A mass transfer model of ammonia volatilisation from anaerobic digestate

    SciTech Connect

    Whelan, M.J.; Everitt, T.; Villa, R.

    2010-10-15

    Anaerobic digestion (AD) is becoming increasingly popular for treating organic waste. The methane produced can be burned to generate electricity and the digestate, which is high in mineral nitrogen, can be used as a fertiliser. In this paper we evaluate potential losses of ammonia via volatilisation from food waste anaerobic digestate using a closed chamber system equipped with a sulphuric acid trap. Ammonia losses represent a pollution source and, over long periods could reduce the agronomic value of the digestate. Observed ammonia losses from the experimental system were linear with time. A simple non-steady-state partitioning model was developed to represent the process. After calibration, the model was able to describe the behaviour of ammonia in the digestate and in the trap very well. The average rate of volatilisation was approximately 5.2 g N m{sup -2} week{sup -1}. The model was used to extrapolate the findings of the laboratory study to a number of AD storage scenarios. The simulations highlight that open storage of digestate could result in significant losses of ammonia to the atmosphere. Losses are predicted to be relatively minor from covered facilities, particularly if depth to surface area ratio is high.

  5. Methane emissions from digestate at an agricultural biogas plant.

    PubMed

    Baldé, Hambaliou; VanderZaag, Andrew C; Burtt, Stephen D; Wagner-Riddle, Claudia; Crolla, Anna; Desjardins, Raymond L; MacDonald, Douglas J

    2016-09-01

    Methane (CH4) emissions were measured over two years at an earthen storage containing digestate from a mesophilic biodigester in Ontario, Canada. The digester processed dairy manure and co-substrates from the food industry, and destroyed 62% of the influent volatile solids (VS). Annual average emissions were 19gCH4m(-3)d(-1) and 0.27gCH4kg(-1)VSd(-1). About 76% of annual emissions occurred from June to October. Annual cumulative emissions from digestate corresponded to 12% of the CH4 produced within the digester. A key contributor to CH4 emissions was the sludge layer in storage, which contained as much VS as the annual discharge from the digester. These findings suggest that digestate management provides an opportunity to further enhance the benefits of biogas (i.e. reducing CH4 emissions compared to undigested liquid manure, and producing renewable energy). Potential best practices for future study include complete storage emptying, solid-liquid separation, and storage covering. PMID:27323243

  6. Effect of age on seed digestion in parrots (Amazona aestiva).

    PubMed

    Vendramin-Gallo, M; Pessutti, C; Pezzato, A C; Vicentini-Paulino, M L

    2001-01-01

    The objective of this study was to compare the capacity of adult (more than 3 yr old) and young (less than 1 yr old) true parrots to digest seeds that are normally included in their diet in captivity, particularly soybean, sunflower, and corn. All the seeds were offered for 5 d with an interval of 15 d between different diets. The seeds of soybean and corn were boiled for 15 min and soaked in water at ambient temperature for 12 h before being fed to the birds. There were no differences in the digestibilities of crude protein and fats (ether extract) among animals, but the digestibilities of dry matter and crude fiber by the adult animals were higher than those of the young ones. The digestibility of carbohydrate (nitrogen-free extract) by adult birds was higher only for sunflower seeds. It is concluded that the capacity of parrots to digest fiber may change according to the age of the animal. Since the digestion of fiber depends on the action of microorganisms, these results suggest that the colonization of the gastrointestinal tract is delayed or very slow in young parrots. PMID:11331512

  7. Flexible digestion strategies and trace metal assimilation in marine bivalves

    USGS Publications Warehouse

    Decho, Alan W.; Luoma, Samuel N.

    1996-01-01

    Pulse-chase experiments show that two marine bivalves take optimal advantage of different types of particulate food by varying food retention time in a flexible two-phase digestive system. For example, carbon is efficiently assimilated from bacteria by subjecting nearly all the ingested bacteria to prolonged digestion. Prolonging digestion also enhances assimilation of metals, many of which are toxic in minute quantities if they are biologically available. Detritus-feeding aquatic organisms have always lived in environments naturally rich in particle-reactive metals. We suggest that avoiding excess assimilation of metals could be a factor in the evolution of digestion strategies. We tested that suggestion by studying digestion of particles containing different Cr concentrations. We show that bivalves are capable of modifying the digestive processing of food to reduce exposure to high, biologically available, Cr concentrations. The evolution of a mechanism in some species to avoid high concentrations of metals in food could influence how effects of modern metal pollution are manifested in marine ecosystems.

  8. Effects of inhomogeneity on triglyceride digestion of emulsions using an in vitro digestion model (Tiny TIM).

    PubMed

    Oosterveld, Alexander; Minekus, Mans; Bomhof, Esther; Zoet, Franklin D; van Aken, George A

    2016-07-13

    The colloidal behaviour and extent of lipolysis of various emulsions stabilized by whey protein and Tween were studied using the TNO Intestinal Model (TIM) extended with a purposely designed gastric compartment. The in vitro results suggest that creaming of a fatty layer in the gastric region causes a delay in fat entering the small intestinal region, delays and reduces the free fatty acid content in the small intestinal lumen and delays fat absorption. It was shown that controlling the pH with pig gastric juice instead of simulated gastric juice delayed creaming of the emulsions significantly, which resulted in faster gastric lipolysis. However, because the digestive conditions are not adjusted by physiological regulation mechanisms such as the regulation of gastric emptying by the detection of nutrients in the small intestine, care must be taken to translate these results to the in vivo reality. It is expected that the differences between the systems will be tempered by the physiological feedback regulation mechanisms of digestion. PMID:27264678

  9. Relationship between anaerobic digestion of biodegradable solid waste and spectral characteristics of the derived liquid digestate.

    PubMed

    Zheng, Wei; Lü, Fan; Phoungthong, Khamphe; He, Pinjing

    2014-06-01

    The evolution of spectral properties during anaerobic digestion (AD) of 29 types of biodegradable solid waste was investigated to determine if spectral characteristics could be used for assessment of biological stabilization during AD. Biochemical methane potential tests were conducted and spectral indicators (including the ratio of ultraviolet-visible absorbance at 254nm to dissolved organic carbon concentration (SUVA254), the ratio of ultraviolet-visible absorbance measured at 465nm and 665nm (E4/E6), and the abundance of fluorescence peaks) were measured at different AD phases. Inter-relationship between organic degradation and spectral indicators were analyzed by principle component analysis. The results shows that from methane production phase to the end of methane production phase, SUVA254 increased by 0.16-10.93 times, the abundance of fulvic acid-like compounds fluorescence peak increased by 0.01-0.54 times, the abundance of tyrosine fluorescence peak decreased by 0.03-0.64 times. Therefore, these indicators were useful to judge the course of mixed waste digestion. PMID:24686373

  10. The functional-morphological adaptive strategy of digestive organs of decapodiform cephalopods

    PubMed Central

    OMURA, Ayano; ENDO, Hideki

    2015-01-01

    The digestive organs in decapodiform cephalopod species morphologically vary by individual lifestyle. We examined the following six species of adult decapodiformes cephalopods representing different habitats: Todarodes pacificus, Loligo bleekeri, Loligo edulis, Watasenia scintillans (pelagic), Sepia lycidas and Euprymna morsei (benthic). L. bleekeri and L. edulis possess a bursiform cecal sac connected to the cecum. Pelagic species have a single digestive gland smaller than in benthic species. T. pacificus has an oval digestive gland larger than that of L. bleekeri and L. edulis, which possess withered-looking and smaller digestive glands. In contrast, the digestive glands in benthic species are paired. S. lycidas and E. morsei have well-developed and larger digestive glands than those of the pelagic species. Well-developed digestive duct appendages are found in benthic species. In qualification of the mass of digestive organs, pelagic species have smaller stomachs, digestive glands and digestive ducts’ appendages than benthic species. Because pelagic species need to swim, they may possess smaller stomachs and larger cecums for more rapid digestion. A smaller digestive gland may have the advantage of reducing the body weight in pelagic species for rapid swimming. In contrast, since benthic species require a longer time for digestion than pelagic species, they compact more food in their stomachs and absorb nutrients via more organs, such as the digestive grand and digestive duct appendages, in addition to cecum. PMID:26369293

  11. The functional-morphological adaptive strategy of digestive organs of decapodiform cephalopods.

    PubMed

    Omura, Ayano; Endo, Hideki

    2016-01-01

    The digestive organs in decapodiform cephalopod species morphologically vary by individual lifestyle. We examined the following six species of adult decapodiformes cephalopods representing different habitats: Todarodes pacificus, Loligo bleekeri, Loligo edulis, Watasenia scintillans (pelagic), Sepia lycidas and Euprymna morsei (benthic). L. bleekeri and L. edulis possess a bursiform cecal sac connected to the cecum. Pelagic species have a single digestive gland smaller than in benthic species. T. pacificus has an oval digestive gland larger than that of L. bleekeri and L. edulis, which possess withered-looking and smaller digestive glands. In contrast, the digestive glands in benthic species are paired. S. lycidas and E. morsei have well-developed and larger digestive glands than those of the pelagic species. Well-developed digestive duct appendages are found in benthic species. In qualification of the mass of digestive organs, pelagic species have smaller stomachs, digestive glands and digestive ducts' appendages than benthic species. Because pelagic species need to swim, they may possess smaller stomachs and larger cecums for more rapid digestion. A smaller digestive gland may have the advantage of reducing the body weight in pelagic species for rapid swimming. In contrast, since benthic species require a longer time for digestion than pelagic species, they compact more food in their stomachs and absorb nutrients via more organs, such as the digestive grand and digestive duct appendages, in addition to cecum. PMID:26369293

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

    PubMed

    Ge, Huoqing; Batstone, Damien; Keller, Jurg

    2016-01-01

    The need to reduce energy input and enhance energy recovery from wastewater is driving renewed interest in high-rate activated sludge treatment (i.e. short hydraulic and solids retention times (HRT and SRT, respectively)). This process generates short SRT activated sludge stream, which should be highly degradable. However, the evaluation of anaerobic digestion of short SRT sludge has been limited. This paper assesses anaerobic digestion of short SRT sludge digestion derived from meat processing wastewater under thermophilic and mesophilic conditions. The thermophilic digestion system (55°C) achieved 60 and 68% volatile solids destruction at 8 day and 10 day HRT, respectively, compared with 50% in the mesophilic digestion system (35°C, 10 day HRT). The digestion effluents from the thermophilic (8-10 day HRT) and mesophilic systems were stable, as assessed by residual methane potentials. The ammonia rich sludge dewatering liquor was effectively treated by a batch anammox process, which exhibited comparable nitrogen removal rate as the tests using a control synthetic ammonia solution, indicating that the dewatering liquor did not have inhibiting/toxic effects on the anammox activity. PMID:26942526

  13. Digestion and degradation, air for life.

    PubMed

    Lettinga, G

    2001-01-01

    Anaerobic degradation of dead biomass is a natural gasification process, an anaerobic crematorium producing a very useful end-product composed of methane and carbon dioxide, generally polluted with small amounts of some malodorous and quite toxic volatile S-compounds. It leads to the production of essential building elements for new life. This exciting field became my faith, vision, hope and expectation. This paper intends to present a reflection of more than three decades of research, teaching and advertisement in the field of sustainable environmental protection technologies, particularly of systems based on anaerobic digestion and the biological sulphur cycle. Considerable progress has been made during these decades worldwide, both in the basic understanding of the various processes and concepts, but also in the implementation of these systems, despite the fact that particularly the implementation frequently proceeded very laboriously. The difficulties certainly can no longer be attributed to technological limitations and/or insufficient understanding of the microbiology and chemistry only, but mainly to the frustrating social rigidity and short-term self-interest in all sectors of our society. By combining anaerobic processes with other microbiological degradation or transformation processes, like those based on the biological sulphur cycle, micro-aerobic and conventional aerobic and anoxic processes, ideal conditions can be created to valorise residues (wastes) from domestic, industrial and agricultural origin. It is simply not just "technology", but also a route to achieve more sustainability and justice in society. It is a fight against conservative establishments. Decomposition, disintegration disbandment, it also stands for deliverance and liberation, space and air for continuation of life. PMID:11730132

  14. Animal and industrial waste anaerobic digestion: USA status report

    SciTech Connect

    Lusk, P.D.

    1996-01-01

    Pollutants from unmanaged animal and bio-based industrial wastes can degrade the environment, and methane emitted from decomposing wastes may contribute to global climate change. One waste management system prevents pollution and converts a disposal problem into a new profit center. Case studies of operating systems indicate that the anaerobic digestion of animal and industrial wastes is a commercially available bioconversion technology with considerable potential for providing profitable coproducts, including a cost-effective renewable fuel. Growth and concentration of the livestock industry create opportunities to properly dispose of the large quantities of manures generated at dairy, swine, and poultry farms. Beyond the farm, extension of the anaerobic digestion process to recover methane has considerable potential for certain classified industries - with a waste stream characterization similar to livestock manures. More than 35 example industries have been identified, and include processors of chemicals, fiber, food, meat, milk, and pharmaceuticals. Some of these industries already recover methane for energy. This status report examines some current opportunities for recovering methane from the anaerobic digestion of animal and industrial wastes in the US. Case studies of operating digesters, including project and maintenance histories, and the operator`s {open_quotes}lessons learned,{close_quotes} are included as a reality check. Factors necessary for successful projects, as well as a list of reasons explaining why some anaerobic digestion projects fail, are provided. The role of management is key; not only must digesters be well engineered and built with high-quality components, they must also be sited at facilities willing to incorporate the uncertainties of a new technology. Anaerobic digestion can provide monetary benefits and mitigate possible pollution problems, thereby sustaining development while maintaining environmental quality.

  15. Cysteine cathepsins as digestive enzymes in the spider Nephilengys cruentata.

    PubMed

    Fuzita, Felipe J; Pinkse, Martijn W H; Verhaert, Peter D E M; Lopes, Adriana R

    2015-05-01

    Cysteine cathepsins are widely spread on living organisms associated to protein degradation in lysosomes, but some groups of Arthropoda (Heteroptera, Coleoptera, Crustacea and Acari) present these enzymes related to digestion of the meal proteins. Although spiders combine a mechanism of extra-oral with intracellular digestion, the sporadic studies on this subject were mainly concerned with the digestive fluid (DF) analysis. Thus, a more complete scenario of the digestive process in spiders is still lacking in the literature. In this paper we describe the identification and characterization of cysteine cathepsins in the midgut diverticula (MD) and DF of the spider Nephilengys cruentata by using enzymological assays. Furthermore, qualitative and quantitative data from transcriptomic followed by proteomic experiments were used together with biochemical assays for results interpretation. Five cathepsins L, one cathepsin F and one cathepsin B were identified by mass spectrometry, with cathepsins L1 (NcCTSL1) and 2 (NcCTSL2) as the most abundant enzymes. The native cysteine cathepsins presented acidic characteristics such as pH optima of 5.5, pH stability in acidic range and zymogen conversion to the mature form after in vitro acidification. NcCTSL1 seems to be a lysosomal enzyme with its recombinant form displaying acidic characteristics as the native ones and being inhibited by pepstatin. Evolutionarily, arachnid cathepsin L may have acquired different roles but its use for digestion is a common feature to studied taxa. Now a more elucidative picture of the digestive process in spiders can be depicted, with trypsins and astacins acting extra-orally under alkaline conditions whereas cysteine cathepsins will act in an acidic environment, likely in the digestive vacuoles or lysosome-like vesicles. PMID:25818482

  16. Performance of a UASB-digester system treating domestic wastewater.

    PubMed

    Alvarez, J A; Armstrong, E; Presas, J; Gómez, M; Soto, M

    2004-10-01

    The anaerobic treatment of raw domestic wastewater by a novel technology consisting of an Up-flow Anaerobic Sludge Bed (UASB) reactor combined with a completely mixed digester for the stabilisation of the UASB sludge was assessed. A pilot-scale plant of the so-called UASB-Digester system was located at the municipal wastewater treatment facility of Santiago de Compostela (Northwest of Spain). The main aim of the Digester was to enhance the biodegradation of influent solids retained in the UASB reactor at low temperatures, then increasing its specific methanogenic activity. The sludge drawn from the middle zone of the UASB entered the upper zone of the Digester and then circulated from the bottom of the Digester to the UASB bottom. Circulating in an automated semi-continuous way, the flow of this sludge stream was selected in order to set a previously defined hydraulic retention time (HRT) (16-27 d) in the digester. The Digester temperature was set at an optimum value ranging from 25 to 35 degrees C. The steady state efficiency of the UASB system, at 6-8 h of HRT, 15-16 degrees C of temperature and 330-360 mg l(-1) of influent total chemical oxygen demand (TCOD) was 79% of total suspended solids (TSS) removal, 52% of TCOD removal and 60% of biological oxygen demand (BOD5) removal. The hydrolysis of retained solids reached 85%, while excess sludge generation was only 7% of influent TCOD. A stable anaerobic (pre)treatment of diluted domestic wastewater was reached as the sludge concentration in the reactor remained mainly constant and the specific methanogenic activity showed a slight increase. PMID:15551833

  17. Digestive enzymes along digestive tract of a carnivorous fish Glyptosternum maculatum (Sisoridae, Siluriformes).

    PubMed

    Xiong, D M; Xie, C X; Zhang, H J; Liu, H P

    2011-02-01

    This study attempted to determine the presence, distribution and levels of digestive proteases, pepsin, amylase and lipase in the homogenates of digestive tract of a freshwater, cold-adapted, carnivorous teleost of Tibet, Glyptosternum maculatum (n= 10, mean weight: 129.6±28.9 g, mean length: 195.1±16.6 mm, approximately 6 years old), at different temperatures and pH levels. The descending order of protease activity was as follows: stomach (pepsin, 16.16±0.96 U/mg protein), anterior intestine (3.18±0.25 U/mg protein), posterior intestine (1.76±0.21 U/mg protein) and middle intestine (1.52±0.23 U/mg protein). Amylase activity levels in descending order were as follows: anterior intestine (0.0062±0.0007 U/mg protein), stomach (0.0032±0.0009 U/mg protein), middle intestine (0.0023±0.0005 U/mg protein) and posterior intestine (0.0023±0.0004 U/mg protein). The highest lipase activity was found in the anterior intestine (0.83±0.25 U/mg protein), followed by posterior intestine (0.51±0.19 U/mg protein), middle intestine (0.48±0.09 U/mg protein) and stomach (0.39±0.10 U/mg protein). The optimal temperature and pH level for protease were 50°C and 9.0-10.0, respectively, along the intestine. The pepsin optima in the stomach were 30°C and 2.0 respectively. The optimal temperature for amylase was found to be 30°C along the digestive tract and the optimal pH was 7.0 in the intestine and 6.0 in the stomach. The optimal temperature and pH levels of lipase were 30°C, pH 6.0 for the stomach and 40-50°C, pH 8.0 for the intestine, respectively. Hepato-somatic index was 1.35±0.2% and relative intestine length was 0.90±0.19. The weight ratio of the stomach and intestine to body weight was 1.63±0.43% and 1.57±0.24% respectively. PMID:20487102

  18. Determination of Iron in Milk Powdermicrowave Digestion and Flame Atomicabsorption Spectrophotometry

    NASA Astrophysics Data System (ADS)

    Zhao, Guangyuan; Li, Bo

    To investigate the conditions of microwave digestion for determining Iron in milk powder by flame atomic absorption spectrophotometry(FAAS), the content of iron in milk powder was determined by flame atomic absorption spectrophotometry after the samples were microwavely digested under different conditions. The optimum parameters for microwave digestion were obtained by the orthogonal test at last. The best optimum parameters for microwave digestion was that, the volume of digestion solution was 8mL, the reagent proportion for HNO3 and H2O2 was 4:1, the digestion time was 8min, the digestion pressure was 2.6 Mpa and the digestion power was 1000 W. The content of Iron in assayed milk powder was 0.0560mg/g. Microwave digestion was a time-saving and practical pretreatment of samples.

  19. A simple digestion method with a Lefort aqua regia solution for diatom extraction.

    PubMed

    Wang, Huipin; Liu, Yan; Zhao, Jian; Hu, Sunlin; Wang, Yuzhong; Liu, Chao; Zhang, Yanji

    2015-01-01

    Presence of diatoms in tissues has been considered as a significant sign of drowning. However, there are limitations in the present extraction methods. We developed a new digestion method using the Lefort aqua regia solution (3:1 nitric acid to hydrochloric acid) for diatom extraction and evaluated the digestive capability, diatom destruction, and diatoms' recovery of this new method. The kidney tissues from rabbit mixed with water rich in diatoms were treated by the Lefort aqua regia digestion method (n = 10) and the conventional acid digestion method (n = 10). The results showed that the digestive capability of Lefort aqua regia digestion method was superior to conventional acid digestion method (p < 0.01); the structure of diatom remained almost intact; and the recovery of diatom was comparable to the conventional acid digestion method (p > 0.05). The Lefort aqua regia reagent is an improvement over the conventional acid digestion for recovery of diatoms from tissue samples. PMID:25399968

  20. Enhancement of the conventional anaerobic digestion of sludge: comparison of four different strategies.

    PubMed

    Pérez-Elvira, S I; Fdz-Polanco, M; Fdz-Polanco, F

    2011-01-01

    Anaerobic digestion (AD) is the preferred option to stabilize sludge. However, the rate limiting step of solids hydrolysis makes it worth modifing the conventional mesophilic AD in order to increase the performance of the digester. The main strategies are to introduce a hydrolysis pre-treatment, or to modify the digestion temperature. Among the different pre-treatment alternatives, the thermal hydrolysis (TH) at 170 degrees C for 30 min, and the ultrasounds pre-treatment (US) at 30 kJ/kg TS were selected for the research, while for the non-conventional anaerobic digestion, the thermophilic (TAD) and the two-stage temperature phased AD (TPAD) were considered. Four pilot plants were operated, with the same configuration and size of anaerobic digester (200 L, continuously fed). The biogas results show a general increase compared to the conventional digestion, being the highest production per unit of digester for the process combining the thermal pre-treatment and AD (1.4 L biogas/L digester day compared to the value of 0.26 obtained in conventional digesters). The dewaterability of the digestate became enhanced for processes TH + AD and TPAD when compared with the conventional digestate, while it became worse for processes US + AD and TAD. In all the research lines, the viscosity in the digester was smaller compared to the conventional (which is a key factor for process performance and economics), and both thermal pre-treatment and thermophilic digestion (TAD and TPAD) assure a pathogen free digestate. PMID:22097010

  1. Determination of gold and silver in geological samples by focused infrared digestion: A re-investigation of aqua regia digestion.

    PubMed

    Wang, Yong; Baker, Laura A; Brindle, Ian D

    2016-02-01

    Focused infrared radiation-based digestions, for the determination of gold and silver, can be achieved in a timeframe as short as 10-15 min, making it an attractive candidate technology for the mining industry, where very large numbers of samples are analyzed on a daily basis. An investigation was carried out into gold and silver dissolution chemistry from geological samples using this novel digestion technique. This study investigated in-depth the issue of low recoveries of gold from aqua regia (AR) digestions, reported by a number of researchers. Conventional AR digestions consistently delivered gold recoveries in a range of 69-80% of the certified values for the four certified reference materials (CRM) employed (CCU-1d, SN26, OREAS 62c, and AMiS 0274), while silver recoveries were satisfactory. By gradually shifting the HCl:HNO3 ratio (v/v) from 3:1 to a reversed 1:3 ratio, recoveries of gold and silver exhibited inverse trends. At a HCl:HNO3 ratio of 1:3, complete recovery of gold was achieved with excellent reproducibility in all CRMs. Meanwhile, silver recoveries plunged significantly at this ratio in samples with higher silver concentrations. Silver values were recovered, however, when the silver was re-solubilized by adding a small volume of concentrated HCl to the cooled reverse aqua regia digests. Recoveries of base metals, such as Fe and Cu, were satisfactory throughout and were much less sensitive to changes in the digestion medium. Using four CRMs and five real-world gold/silver containing samples, the utility of the proposed reverse aqua regia was systematically studied. The uncomplicated nature of the digestion methods reported here, that are fast, effective and inexpensive, may be useful to analysts developing/optimizing their methods for the rapid determination of Au and Ag in a variety of mineral phases, particularly where rapid results are desirable, such as in prospecting and mine development. PMID:26653468

  2. Assessments of lung digestion methods for recovery of fibers.

    PubMed

    Warheit, D B; Hwang, H C; Achinko, L

    1991-04-01

    Evaluation of the pulmonary hazards associated with exposure to fibrous materials tends to be more complicated than assessments required for particulate materials. Fibers are defined by aspect ratios and it is generally considered that physical dimensions play an important role in the pathogenesis of fiber-related lung diseases. Several digestion techniques have been used to recover fibers from exposed lung tissue for clearance studies. Because many of the digestion fluids are corrosive (e.g., bleach, KOH), it is conceivable that the dimensions of recovered fibers are modified during the tissue digestion methods to assess whether the physical dimensions of bulk samples of fibers were altered following simulated digestion processing. Aliquots of crocidolite and chrysotile asbestos, Kevlar aramid, wollastonite, polyacrylonitrile (pan)-based carbon, and glass fibers were incubated with either saline, bleach, or KOH and then filtered. Scanning electron microscopy techniques were utilized to measure the physical dimensions (i.e., lengths and diameters) of at least 160 fibers per treatment group of each fiber type. Our results showed that the lengths and diameters of glass fibers and wollastonite were altered after treatment with KOH. In addition, treatment with bleach produced a small reduction in both asbestos fiber-type diameters, and greater changes in Kevlar and wollastonite diameters and carbon fiber lengths (P less than 0.05). These results indicate that lung digestion methods should be carefully assessed for each fiber type before initiating fiber clearance studies. PMID:1851478

  3. Effect of pectin on anaerobic digestion of cattle dung

    SciTech Connect

    Madamwar, D.B.; Mithal, B.M.

    1986-04-01

    It is therefore desirable to discover procedures to increase the rate of digestion. It has been reported that addition of powdered activated carbon results in an increase in total gas production with high methane content. Based on a review of the literature, it is evident that carbon is responsible for improved digestion. The surface of the activated carbon provides adsorption sites where substrate can accumulate, thereby providing high localized substrate concentration. These areas of adsorption provide a more favorable growth environment for bacterial-substrate systems. No study, however, seems to have been made so far on the effect of other additives like pectin on anaerobic digestion of cattle dung. Since pectin is also used as one of the adsorbents in many cases, it appears desirable to study the effect of pectin on anaerobic digestion of cattle dung with the ultimate aim of improving the production of gas with increased methane content. Experiments carried out with this object in view are reported in this paper. The impact of pectin on volatile acid, pH, and process stability has also been examined. This paper presents the results of two sets of experiments involving pectin addition to bench-scale digesters. One set of experiments is carried out at a controlled temperature of 38 +/- 1 degree C, while the other is carried out at ambient temperature-ambient temperature varied from 40 to 15 degrees C, that is from August to November. 14 references.

  4. Effect of alkaline pretreatment on anaerobic digestion of solid wastes.

    PubMed

    López Torres, M; Espinosa Lloréns, Ma del C

    2008-11-01

    The introduction of the anaerobic digestion for the treatment of the organic fraction of municipal solid waste (OFMSW) is currently of special interest. The main difficulty in the treatment of this waste fraction is its biotransformation, due to the complexity of organic material. Therefore, the first step must be its physical, chemical and biological pretreatment for breaking complex molecules into simple monomers, to increase solubilization of organic material and improve the efficiency of the anaerobic treatment in the second step. This paper describes chemical pretreatment based on lime addition (Ca(OH)2), in order to enhance chemical oxygen demand (COD) solubilization, followed by anaerobic digestion of the OFMSW. Laboratory-scale experiments were carried out in completely mixed reactors, 1 L capacity. Optimal conditions for COD solubilization in the first step of pretreatment were 62.0 mEq Ca(OH)2/L for 6.0 h. Under these conditions, 11.5% of the COD was solubilized. The anaerobic digestion efficiency of the OFMSW, with and without pretreatment, was evaluated. The highest methane yield under anaerobic digestion of the pretreated waste was 0.15 m3CH4/kg volatile solids (VS), 172.0% of the control. Under that condition the soluble COD and VS removal were 93.0% and 94.0%, respectively. The results have shown that chemical pretreatment with lime, followed by anaerobic digestion, provides the best results for stabilizing the OFMSW. PMID:18068345

  5. Ultrafast microwave-assisted in-tip digestion of proteins.

    PubMed

    Hahn, Hans W; Rainer, Matthias; Ringer, Thomas; Huck, Christian W; Bonn, Günther K

    2009-09-01

    Trypsin was immobilized on glycidylmethacrylate-co-divinylbenzene (GMA/DVB) polymerized in pipet tips for online enzymatic digestion of proteins. The major advantages of in-tip digestion are easy handling and small sample amount required for analysis. Microwave-assisted digestion was applied for highly efficient and time saving proteolysis. Adaption to an automated robotic system allowed fast and reproducible sample treatment. Investigations with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) and liquid chromatography coupled with electrospray-ionization mass spectrometry (LC-ESI/MS) attested high sequence coverages (SCs) for the three standard proteins, myoglobin (Myo, 89%), bovine serum albumin (BSA, 78%) and alpha-casein (alpha-Cas, 83%). Compared to commercially available trypsin tips, clear predominance concerning the digestion performance was achieved. Storageability was tested over a period of several weeks and results showed only little decrease (<5%) of protein sequence coverages. The application of microwave-assisted in-tip digestion (2 min) with full automation by a robotic system allows high-throughput analysis (96 samples within 80 min) and highly effective proteolysis. PMID:19639939

  6. Factors controlling pathogen destruction during anaerobic digestion of biowastes

    SciTech Connect

    Smith, S.R. . E-mail: s.r.smith@imperial.ac.uk; Lang, N.L.; Cheung, K.H.M.; Spanoudaki, K.

    2005-07-01

    Anaerobic digestion is the principal method of stabilising biosolids from urban wastewater treatment in the UK, and it also has application for the treatment of other types of biowaste. Increasing awareness of the potential risks to human and animal health from environmental sources of pathogens has focused attention on the efficacy of waste treatment processes at destroying pathogenic microorganisms in biowastes recycled to agricultural land. The degree of disinfection achieved by a particular anaerobic digester is influenced by a variety of interacting operational variables and conditions, which can often deviate from the ideal. Experimental investigations demonstrate that Escherichia coli and Salmonella spp. are not damaged by mesophilic temperatures, whereas rapid inactivation occurs by thermophilic digestion. A hydraulic, biokinetic and thermodynamic model of pathogen inactivation during anaerobic digestion showed that a 2 log{sub 10} reduction in E. coli (the minimum removal required for agricultural use of conventionally treated biosolids) is likely to challenge most conventional mesophilic digesters, unless strict maintenance and management practices are adopted to minimise dead zones and by-pass flow. Efficient mixing and organic matter stabilisation are the main factors controlling the rate of inactivation under mesophilic conditions and not a direct effect of temperature per se on pathogenic organisms.

  7. Effect of ultrasonication on anaerobic degradability of solid waste digestate.

    PubMed

    Boni, M R; D'Amato, E; Polettini, A; Pomi, R; Rossi, A

    2016-02-01

    This paper evaluates the effect of ultrasonication on anaerobic biodegradability of lignocellulosic residues. While ultrasonication has been commonly applied as a pre-treatment of the feed substrate, in the present study a non-conventional process configuration based on recirculation of sonicated digestate to the biological reactor was evaluated at the lab-scale. Sonication tests were carried out at different applied energies ranging between 500 and 50,000kJ/kg TS. Batch anaerobic digestion tests were performed on samples prepared by mixing sonicated and untreated substrate at two different ratios (25:75 and 75:25 w/w). The results showed that when applied as a post-treatment of digestate, ultrasonication can positively affect the yield of anaerobic digestion, mainly due to the dissolution effect of complex organic molecules that have not been hydrolyzed by biological degradation. A good correlation was found between the CH4 production yield and the amount of soluble organic matter at the start of digestion tests. The maximum gain in biogas production was 30% compared to that attained with the unsonicated substrate, which was tentatively related to the type and concentration of the metabolic products. PMID:26586420

  8. Can Delignification Decrease Cellulose Digestibility in Acid Pretreated Corn Stover?

    SciTech Connect

    Ishizawa, C. I.; Jeoh, T.; Adney, W. S.; Himmel, M. E.; Johnson, D. K.; Davis, M. F.

    2009-01-01

    It has previously been shown that the improved digestibility of dilute acid pretreated corn stover is at least partially due to the removal of xylan and the consequent increase in accessibility of the cellulose to cellobiohydrolase enzymes. We now report on the impact that lignin removal has on the accessibility and digestibility of dilute acid pretreated corn stover. Samples of corn stover were subjected to dilute sulfuric acid pretreatment with and without simultaneous (partial) lignin removal. In addition, some samples were completely delignified after the pretreatment step using acidified sodium chlorite. The accessibility and digestibility of the samples were tested using a fluorescence-labeled cellobiohydrolase (Trichoderma reesei Cel7A) purified from a commercial cellulase preparation. Partial delignification of corn stover during dilute acid pretreatment was shown to improve cellulose digestibility by T. reesei Cel7A; however, decreasing the lignin content below 5% (g g{sup -1}) by treatment with acidified sodium chlorite resulted in a dramatic reduction in cellulose digestibility. Importantly, this effect was found to be enhanced in samples with lower xylan contents suggesting that the near complete removal of xylan and lignin may cause aggregation of the cellulose microfibrils resulting in decreased cellulase accessibility.

  9. Effect of alkaline pretreatment on anaerobic digestion of solid wastes

    SciTech Connect

    Lopez Torres, M. Espinosa Llorens, Ma. del C.

    2008-11-15

    The introduction of the anaerobic digestion for the treatment of the organic fraction of municipal solid waste (OFMSW) is currently of special interest. The main difficulty in the treatment of this waste fraction is its biotransformation, due to the complexity of organic material. Therefore, the first step must be its physical, chemical and biological pretreatment for breaking complex molecules into simple monomers, to increase solubilization of organic material and improve the efficiency of the anaerobic treatment in the second step. This paper describes chemical pretreatment based on lime addition (Ca(OH){sub 2}), in order to enhance chemical oxygen demand (COD) solubilization, followed by anaerobic digestion of the OFMSW. Laboratory-scale experiments were carried out in completely mixed reactors, 1 L capacity. Optimal conditions for COD solubilization in the first step of pretreatment were 62.0 mEq Ca(OH){sub 2}/L for 6.0 h. Under these conditions, 11.5% of the COD was solubilized. The anaerobic digestion efficiency of the OFMSW, with and without pretreatment, was evaluated. The highest methane yield under anaerobic digestion of the pretreated waste was 0.15 m{sup 3} CH{sub 4}/kg volatile solids (VS), 172.0% of the control. Under that condition the soluble COD and VS removal were 93.0% and 94.0%, respectively. The results have shown that chemical pretreatment with lime, followed by anaerobic digestion, provides the best results for stabilizing the OFMSW.

  10. Assessments of lung digestion methods for recovery of fibers

    SciTech Connect

    Warheit, D.B.; Hwang, H.C.; Achinko, L. )

    1991-04-01

    Evaluation of the pulmonary hazards associated with exposure to fibrous materials tends to be more complicated than assessments required for particulate materials. Fibers are defined by aspect ratios and it is generally considered that physical dimensions play an important role in the pathogenesis of fiber-related lung diseases. Several digestion techniques have been used to recover fibers from exposed lung tissue for clearance studies. Because many of the digestion fluids are corrosive (e.g., bleach, KOH), it is conceivable that the dimensions of recovered fibers are modified during the tissue digestion process, thus creating erroneous data. Accordingly, the authors evaluated two lung digestion methods to assess whether the physical dimensions of bulk samples of fibers were altered following simulated digestion processing. Aliquots of crocidolite and chrysotile asbestos, Kevlar aramid, wollastonite, polyacrylonitrile (pan)-based carbon, and glass fibers were incubated with either saline, bleach, or KOH and then filtered. Scanning electron microscopy techniques were utilized to measure the physical dimensions (i.e., lengths and diameters) of at least 160 fibers per treatment group of each fiber type. Their results showed that the lengths and diameters of glass fibers and wollastonite were altered after treatment with KOH. In addition, treatment with bleach produced a small reduction in both asbestos fiber-type diameters, and greater changes in Kevlar and wollastonite diameters and carbon fiber lengths.

  11. Anaerobic digestion of solid wastes of cane sugar industry

    SciTech Connect

    Dasgupta, A.

    1983-01-01

    The cane sugar manufacturing industry generates large quantities of lignocellulosic solid wastes, namely bagasse and cachaza. Bagasse is the fibrous residue of the cane after extracting the juice. Cachaza is the filter cake of the precipitated insoluble sugars. This research investigates the feasibility of anaerobic digestion of a mixture of bagasse and cachaza to produce methane. Two rations of bagasse-cachaza mix as substrates were investigated. The first one was 8:1 which represents the average ratio of bagasse and cachaza produced in a raw sugar mill. The second ratio investigated was 2.4:1 which represents the proportion of bagasse and cachaza wastes after 70% of the bagasse is burned in sugar mill boilers. An acclimated microbial culture for this substrate was developed. Organic Loading-Detention Time relationships were established for an optimum system. Pre-treatment techniques of the substrate were investigated as a means of enhancing the digestibility of the cellulosic substrate. Recirculation of the filtrate was evaluated as a method for increasing solids retention time without increasing hydraulic detention time. The kinetics of the digestion process for bagasse-cachaza mixed substrate was investigated and growth constants were determined. The bionutritional characteristics of the substrate used for the digestion were evaluated. Based on the results obtained, mass balances and preliminary economic analysis of the digestion system were developed.

  12. Cooking and grinding reduces the cost of meat digestion.

    PubMed

    Boback, Scott M; Cox, Christian L; Ott, Brian D; Carmody, Rachel; Wrangham, Richard W; Secor, Stephen M

    2007-11-01

    The cooking of food is hypothesized to have played a major role in human evolution partly by providing an increase in net energy gain. For meat, cooking compromises the structural integrity of the tissue by gelatinizing the collagen. Hence, cooked meat should take less effort to digest compared to raw meat. Likewise, less energy would be expended digesting ground meat compared to intact meat. We tested these hypotheses by assessing how the cooking and/or grinding of meat influences the energy expended on its digestion, absorption, and assimilation (i.e., specific dynamic action, SDA) using the Burmese python, Python molurus. Pythons were fed one of four experimental diets each weighing 25% of the snake's body mass: intact raw beef, intact cooked beef, ground raw beef, and ground cooked beef. We measured oxygen consumption rates of snakes prior to and up to 14 days following feeding and calculated SDA from the extra oxygen consumed above standard metabolic rate. Postprandial peak in oxygen consumption, the scope of peak rates, and SDA varied significantly among meal treatments. Pythons digesting raw or intact meals exhibited significantly larger postprandial metabolic responses than snakes digesting the cooked ground meals. We found cooking to decrease SDA by 12.7%, grinding to decrease SDA by 12.4%, and the combination of the two (cooking and grinding) to have an additive effect, decreasing SDA by 23.4%. These results support the hypothesis that the consumption of cooked meat provides an energetic benefit over the consumption of raw meat. PMID:17827047

  13. Anaerobic digestion of wheat straw--performance of continuous solid-state digestion.

    PubMed

    Pohl, Marcel; Heeg, Kathrin; Mumme, Jan

    2013-10-01

    In this study the upflow anaerobic solid-state (UASS) reactor was operated at various conditions to optimize the process parameters for anaerobically digesting wheat straw in a continuous process. Additionally, particle size effects have been studied in the operation at 55 and 60°C. Moreover, the incremental effect of the organic loading rate (OLR) to the system was examined from 2.5 to 8 gVS L(-1) d(-1). It was found that the UASS operating at 60 °C with a small OLR yields highest methane production, but the advantage over thermophilic operation is negligible. The rise in OLR reduces the systems yields, as expected. From OLR=8 gVS L(-1) d(-1) a second stage is necessary to circumvent volatile fatty acids accumulation. PMID:23954246

  14. Prediction of digestible energy and gross energy digestibility of feeds and diets in ostriches.

    PubMed

    Bovera, F; Nizza, S; Attia, Y A; Di Meo, C; Piccolo, G; Nizza, A

    2014-01-01

    1. The aim of this study was to assess regression equations able to predict the digestible energy (DE) and gross energy digestibility (GEd) of feed ingredients and diets for ostriches. 2. Results of chemical-nutritional characteristics from 17 ingredients (two varieties of maize, two barleys, oat, triticale, wheat bran, soybean meal, sunflower meal, beet pulp, maize silage, alfalfa hay, 4 alfalfa meals and lupin) and 12 experimental diets were used in a stepwise procedure. 3. Acid detergent lignin (ADL) was the first independent variable included in the model to predict the DE of all the samples (R(2) = 0.65 and Residual Standard Deviation (RSD) 1.02). When the concentration of ash, acid detergent fibre (ADF) and crude fibre were included in the model, the R(2) value of the regression equation increased (from 0.65 to 0.85) and RSD decreased (from 1.02 to 0.48). 4. The ADL concentration was also the first independent variable chosen by the stepwise regression analysis for the estimation of GEd from chemical-nutritional characteristics of feeds, explaining 57% of the total GEd variation. The concentrations of crude protein and ADF included at the second and third steps in the model increased the R(2) (up to 0.70 and 0.73, respectively) and decreased the RSD values (from 0.29 to 0.21 and 0.20, respectively). When other variables as crude fibre, ash and gross energy were included in the model, the coefficient of determination and the RSD strongly improved (0.85 and 0.12, respectively). PMID:24945235

  15. Investigation of Poultry Waste for Anaerobic Digestion: A Case Study

    NASA Astrophysics Data System (ADS)

    Salam, Christopher R.

    Anaerobic Digestion (AD) is a biological conversion technology which is being used to produce bioenergy all over the world. This energy is created from biological feedstocks, and can often use waste products from various food and agricultural processors. Biogas from AD can be used as a fuel for heating or for co-generation of electricity and heat and is a renewable substitute to using fossil fuels. Nutrient recycling and waste reduction are additional benefits, creating a final product that can be used as a fertilizer in addition to energy benefits. This project was conducted to investigate the viability of three turkey production wastes as AD feedstock: two turkey litters and a material separated from the turkey processing wastewater using dissolved air flotation (DAF) process. The DAF waste contained greases, oils and other non-commodity portions of the turkey. Using a variety of different process methods, types of bacteria, loading rates and food-to-microorganism ratios, optimal loading rates for the digestion of these three materials were obtained. In addition, the co-digestion of these materials revealed additional energy benefits. In this study, batch digestion tests were carried out to treat these three feedstocks, using mesophilic and thermophilic bacteria, using loading rates of 3 and 6 gVS/L They were tested separately and also as a mixture for co-digestion. The batch reactor used in this study had total and working volumes of 1130 mL and 500 mL, respectively. The initial organic loading was set to be 3 gVS/L, and the food to microorganism ratio was either 0.6 or 1.0 for different treatments based on the characteristics of each material. Only thermophilic (50 +/- 2ºC) temperatures were tested for the litter and DAF wastes in continuous digestion, but mesophilic and thermophilic batch digestion experiments were conducted. The optimum digestion time for all experiments was 14 days. The biogas yields of top litter, mixed litter, and DAF waste under

  16. Two-stage upflow anaerobic digestion of concentrated sludge

    SciTech Connect

    Ghosh, S.; Sajjad, A.; Henry, M.P.; Bleakney, R.A.

    1983-01-01

    The development of an innovative fermentation mode, two-stage digestion, and the application of a novel upflow reactor design to permit biogasification of high-solids-content wastewater sludges at higher loading rates and lower-than-normal hydraulic residence times (HRT) to obtain higher gas and methane yields and production rates and better effluent qualities than those achieved with conventional single-stage continuously stirred tank reactor (CSTR) digesters are presented. A bench-scale two-stage upflow system operated with primary sludge at a 5.6-day HRT (1.2 days for Stage 1 and 4.4 days for Stage 2) exhibited a methane yield of 6.8 SCF/lb VS added, which was about 350% higher than that from conventional digestion at the same HRT.

  17. The IWA Anaerobic Digestion Model No 1 (ADM1).

    PubMed

    Batstone, D J; Keller, J; Angelidaki, I; Kalyuzhnyi, S V; Pavlostathis, S G; Rozzi, A; Sanders, W T M; Siegrist, H; Vavilin, V A

    2002-01-01

    The IWA Anaerobic Digestion Modelling Task Group was established in 1997 at the 8th World Congress on Anaerobic Digestion (Sendai, Japan) with the goal of developing a generalised anaerobic digestion model. The structured model includes multiple steps describing biochemical as well as physicochemical processes. The biochemical steps include disintegration from homogeneous particulates to carbohydrates, proteins and lipids; extracellular hydrolysis of these particulate substrates to sugars, amino acids, and long chain fatty acids (LCFA), respectively; acidogenesis from sugars and amino acids to volatile fatty acids (VFAs) and hydrogen; acetogenesis of LCFA and VFAs to acetate; and separate methanogenesis steps from acetate and hydrogen/CO2. The physico-chemical equations describe ion association and dissociation, and gas-liquid transfer. Implemented as a differential and algebraic equation (DAE) set, there are 26 dynamic state concentration variables, and 8 implicit algebraic variables per reactor vessel or element. Implemented as differential equations (DE) only, there are 32 dynamic concentration state variables. PMID:12188579

  18. Relating Anaerobic Digestion Microbial Community and Process Function

    PubMed Central

    Venkiteshwaran, Kaushik; Bocher, Benjamin; Maki, James; Zitomer, Daniel

    2015-01-01

    Anaerobic digestion (AD) involves a consortium of microorganisms that convert substrates into biogas containing methane for renewable energy. The technology has suffered from the perception of being periodically unstable due to limited understanding of the relationship between microbial community structure and function. The emphasis of this review is to describe microbial communities in digesters and quantitative and qualitative relationships between community structure and digester function. Progress has been made in the past few decades to identify key microorganisms influencing AD. Yet, more work is required to realize robust, quantitative relationships between microbial community structure and functions such as methane production rate and resilience after perturbations. Other promising areas of research for improved AD may include methods to increase/control (1) hydrolysis rate, (2) direct interspecies electron transfer to methanogens, (3) community structure–function relationships of methanogens, (4) methanogenesis via acetate oxidation, and (5) bioaugmentation to study community–activity relationships or improve engineered bioprocesses. PMID:27127410

  19. Physicochemical properties and digestibility of hydrothermally treated waxy rice starch.

    PubMed

    Zeng, Feng; Ma, Fei; Kong, Fansheng; Gao, Qunyu; Yu, Shujuan

    2015-04-01

    Waxy rice starch was subjected to annealing (ANN) and heat-moisture treatment (HMT). These starches were also treated by a combination of ANN and HMT. The impact of single and dual modifications (ANN-HMT and HMT-ANN) on the molecular weight (M(w)), crystalline structure, thermal properties, and the digestibility were investigated. The relative crystallinity and short-range order on the granule surface increased on ANN, whereas decreased on HMT. All treated starches showed lower M(w) than that of the native starch. Gelatinization onset temperature, peak temperature and conclusion temperature increased for both single and dual treatments. Increased slowly digestible starch content was found on HMT and ANN-HMT. However, resistant starch levels decreased in all treated starches as compared with native starch. The results would imply that hydrothermal treatment induced structural changes in waxy rice starch significantly affected its digestibility. PMID:25442528

  20. Biogas production from anaerobic digestion of Spirulina maxima algal biomass

    SciTech Connect

    Samson, R.; LeDuy, A.

    1982-08-01

    The semimicroscopic blue-green alga Spirulina maxima makes an ideal substrate for anaerobic digestion because it is easy to harvest, it can use carbon dioxide from the atmosphere as its carbon source, and its fermentability is higher than that of other small algae. Digestion experiments demonstrated that S. maxima can serve as the sole nutrient for biogas production and that municipal sewage sludge, when adapted to this new substrate, is very stable. During semicontinuous daily-fed trials under non-optimal conditions at an 0.06 lb volatile solids (VS)/ft/sup 3/ (0.97 kg VS/m/sup 3/) loading rate, 33-day retention time, and 86/sup 0/F (30/sup 0/C) digestion temperature, the daily methane yield was 4.2 CF/lb (0.26 m/sup 3//kg) VS added, which represents 47% of the maximum theoretical yield. Studies on optimizing the process are underway.

  1. Isolation of protoplasts from undaria pinnatifida by alginate lyase digestion

    NASA Astrophysics Data System (ADS)

    Xiaoke, Hu; Xiaolu, Jiang; Huashi, Guan

    2003-04-01

    The aim of this study is to isolate protoplasts from Undaria pinnatifida. Protoplasts of the alga were isolated enzymatically by using alginate lyase, which was prepared by fermenting culture of a strain Vibrio sp. 510. Monofacterial method was applied for optimizing digestion condition. The optimum condition for protoplast preparation is enzymatic digestion at 28°C for 2h using alginate lyase at the concentration of 213.36 U (8 mL) every 0.5g fresh thalline with NaCl 50 and at the shaking speed of 150 r min-1 during digestion. The protoplast yield can reach 2.62±0.09 million per 0.5 g fresh leave under the optimum condition. The enzyme activity is inhibited by Ca2+ and slightly enhanced by Fe2+ and Mn2+ at concentrations of 0.05, 0.08 and 0.10 mol L-1.

  2. [Severe digestive manifestations of rheumatoid purpura in adults].

    PubMed

    Roche, B; Blazquez, M; Charlier, A; Bognel, J C

    1994-01-01

    The authors report three cases of Scholein-Henoch's purpura in adults which were characterized by atypical severity of the digestive signs which led to laparotomy. In one case, the digestive signs preceded the onset of the cutaneous purpura, which made the diagnosis difficult. The digestive impact was confirmed endoscopically (petechia, ulceration, ulcerated stenosis) in two of the three patients. Damage of the small intestine predominated, as in the literature, but only one patient required resection of the intestine. These observations highlight the importance of endoscopic exploration in cases of abdominal signs combined with Scholein-Henoch's purpura in adults. They also demonstrate the difficulty of evaluating the prognosis and treatment in severe, peritoneo-occlusive forms. PMID:8192421

  3. Molecular physiology of vesicular glutamate transporters in the digestive system

    PubMed Central

    Li, Tao; Ghishan, Fayez K.; Bai, Liqun

    2005-01-01

    Glutamate is the major excitatory neurotransmitter in the mammalian central nervous system (CNS). Packaging and storage of glutamate into glutamatergic neuronal vesicles require ATP-dependent vesicular glutamate uptake systems, which utilize the electrochemical proton gradient as a driving force. Three vesicular glutamate transporters (VGLUT1-3) have been recently identified from neuronal tissue where they play a key role to maintain the vesicular glutamate level. Recently, it has been demonstrated that glutamate signaling is also functional in peripheral neuronal and non-neuronal tissues, and occurs in sites of pituitary, adrenal, pineal glands, bone, GI tract, pancreas, skin, and testis. The glutamate receptors and VGLUTs in digestive system have been found in both neuronal and endocrinal cells. The glutamate signaling in the digestive system may have significant relevance to diabetes and GI tract motility disorders. This review will focus on the most recent update of molecular physiology of digestive VGLUTs. PMID:15793854

  4. Digestion in sea urchin larvae impaired under ocean acidification

    NASA Astrophysics Data System (ADS)

    Stumpp, Meike; Hu, Marian; Casties, Isabel; Saborowski, Reinhard; Bleich, Markus; Melzner, Frank; Dupont, Sam

    2013-12-01

    Larval stages are considered as the weakest link when a species is exposed to challenging environmental changes. Reduced rates of growth and development in larval stages of calcifying invertebrates in response to ocean acidification might be caused by energetic limitations. So far no information exists on how ocean acidification affects digestive processes in marine larval stages. Here we reveal alkaline (~pH 9.5) conditions in the stomach of sea urchin larvae. Larvae exposed to decreased seawater pH suffer from a drop in gastric pH, which directly translates into decreased digestive efficiencies and triggers compensatory feeding. These results suggest that larval digestion represents a critical process in the context of ocean acidification, which has been overlooked so far.

  5. Nuclear Regulatory Commission Information Digest 1994 edition. Volume 6

    SciTech Connect

    Stadler, L.

    1994-03-01

    The Nuclear Regulatory Commission Information Digest (digest) provides a summary of information about the US Nuclear Regulatory Commission (NRC), NRCs regulatory responsibility the activities NRC licenses, and general information on domestic and worldwide nuclear energy. The digest, published annually, is a compilation of nuclear-and 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 1993, with exceptions noted. Information on generating capacity and average capacity factor for operating US commercial nuclear power reactors is obtained from monthly operating reports that are submitted directly to the NRC by the information is reviewed by the NRC for consistency only and no independent validation and/or verification is performed.

  6. CFD simulation of mixing in egg-shaped anaerobic digesters.

    PubMed

    Wu, Binxin

    2010-03-01

    A computational fluid dynamics (CFD) model that characterizes mechanical draft tube mixing in egg-shaped anaerobic digesters was developed. Simulation of flow patterns were carried out with a propeller rotating from 400 to 750rpm, assuming liquid manure to be Newtonian (water) and non-Newtonian fluids depending on the total solids (TS) concentration. Power number and flow number of the propeller in water mixing were validated against lab specifications and experimental data from a field test. The rotational direction and placement of the propeller were examined to identify the primary pumping mode and the optimum position of the propeller fixed inside the tube. Quantitative comparisons of two mixing methods and two digester shapes indicated that mechanical draft tube mixing is more efficient than external pumped recirculation, and that the egg shape provides for more efficient mixing than the cylindrical shape. Furthermore, scale-up rules for mixing in egg-shaped digesters were investigated. PMID:19913870

  7. Microwave and ultrasound pre-treatments influence microbial community structure and digester performance in anaerobic digestion of waste activated sludge.

    PubMed

    Westerholm, Maria; Crauwels, Sam; Van Geel, Maarten; Dewil, Raf; Lievens, Bart; Appels, Lise

    2016-06-01

    Comparative analyses of bacterial and archaeal community structures and dynamics in three biogas digesters during start-up and subsequent operation using microwaved, ultrasonicated or untreated waste activated sludge were performed based on 454 pyrosequencing datasets of part of 16S ribosomal RNA sequences and quantitative PCR. The pre-treatment increased the solubility, and thus the availability of the substrate for microbial degradation and significantly affected the succession of the anaerobic community structure over the course of the digestion. Bacteroidetes, Proteobacteria and Firmicutes were the dominant phyla in all digesters throughout operation. Proteobacteria decreased in relative abundance from 23-26 % to 11-13 % in association with enhanced substrate availability. Negative correlations between relative abundance of Alpha-, Beta- and Gammaproteobacteria and the substrate availability and/or biogas production were disclosed in statistical analyses. Clostridiales was the dominant order in Firmicutes, and Clostridiales, Clostridia and Firmicutes relative abundance and richness were shown to positively correlate with substrate availability and biogas generation. Methanogenic communities had a fairly restricted structure, highly dominated by Methanosaeta and Methanobrevibacter phylotypes. A gradual decline in Methanobrevibacter and increased representation of Methanosaeta concilii over time were particularly apparent in the digester receiving untreated waste activated sludge, whereas more diversified archaeal communities were maintained in the pre-treatment digesters. The quantitative PCR analyses revealed a methanogenic community distribution that coincided with the 454 pyrosequencing data. PMID:26816092

  8. Modelling of two-stage anaerobic digestion using the IWA Anaerobic Digestion Model No. 1 (ADM1).

    PubMed

    Blumensaat, F; Keller, J

    2005-01-01

    The aim of the study presented was to implement a process model to simulate the dynamic behaviour of a pilot-scale process for anaerobic two-stage digestion of sewage sludge. The model implemented was initiated to support experimental investigations of the anaerobic two-stage digestion process. The model concept implemented in the simulation software package MATLAB/Simulink is a derivative of the IWA Anaerobic Digestion Model No.1 (ADM1) that has been developed by the IWA task group for mathematical modelling of anaerobic processes. In the present study the original model concept has been adapted and applied to replicate a two-stage digestion process. Testing procedures, including balance checks and 'benchmarking' tests were carried out to verify the accuracy of the implementation. These combined measures ensured a faultless model implementation without numerical inconsistencies. Parameters for both, the thermophilic and the mesophilic process stage, have been estimated successfully using data from lab-scale experiments described in literature. Due to the high number of parameters in the structured model, it was necessary to develop a customised procedure that limited the range of parameters to be estimated. The accuracy of the optimised parameter sets has been assessed against experimental data from pilot-scale experiments. Under these conditions, the model predicted reasonably well the dynamic behaviour of a two-stage digestion process in pilot scale. PMID:15607176

  9. Two-phase anaerobic co-digestion of olive mill wastes in semi-continuous digesters at mesophilic temperature.

    PubMed

    Fezzani, Boubaker; Ben Cheikh, Ridha

    2010-03-01

    This study investigates for the first time, on laboratory scale, the possible exploitation of the advantages of two-phase anaerobic digestion for treating a mixture of olive mill wastewater (OMW) and olive mill solid waste (OMSW) using two sequencing semi-continuous digesters operated at mesophilic temperature (37+/-2 degrees C). The experiments were conducted at hydraulic retention times (HRTs) of 14 and 24 days corresponding to organic loading rates (OLRs) ranging from 5.54 to 14 g COD/L/day in the first stage (acidifier) and at HRTs of 18, 24 and 36 days corresponding to OLRs ranging from 2.28 to 9.17 g COD/L/day in the second stage (methanizer). The results indicated that volatile fatty acids (VFA) concentrations increased with the increase of either HRT or feed concentration and their high values were obtained with the most concentrated influent (196+/-5 g COD/L) digested at the longest HRT (24 days) corresponded to an OLR of 8.17 g COD/L/d. Furthermore, two-phase anaerobic digestion system has given the best performances concerning methane productivity, soluble COD (SCOD) and phenol removal efficiencies and effluent quality compared to those given by conventional one-phase anaerobic digestion (AD) reactors. PMID:19896368

  10. Metabolizable energy and fiber digestibility of uncommon feedstuffs for geese.

    PubMed

    Zhang, S J; Zhu, C H; Guo, J; Tang, Q P; Li, H F; Zou, J M

    2013-07-01

    This experiment was conducted to study the digestibility of uncommon feedstuffs for geese. Thirty Taihu ganders were selected and divided into 5 groups (n = 6), and one group was allocated as the control. Taihu ganders in the 4 treated groups were force-fed with a weight of different uncommon feedstuffs after 24 h of fasting, and the control group was kept in fasting with no force feeding. All excretion of each gander was collected on a plate for 24 h after force feeding. There was a 12-d recovery period between treatments. In this study, we measured the ME and analyzed neutral detergent fiber, acid detergent fiber, and hemicellulose of brewers grains, distillers grains, empty-grain rice, ryegrass powder, rice husk, corn stalk, rice straw, wheat straw, wheat husk, mushroom bran, and peanut vine. The TME values were 9.29, 8.67, 8.97, 5.89, 3.85, 3.10, 3.32, 3.02, 5.29, 2.48, and 3.15 MJ/kg, respectively. The digestibility of neutral detergent fiber for the feedstuffs ranged from 6.14 to 45.0%, the digestibility of acid detergent fiber ranged from 4.52 to 32.6%, and the digestibility of hemicellulose ranged from 18.5 to 61.6%. The best TME quadratic prediction equation was TME = 12.2 - 0.232CF, where CF is crude fiber. These results suggest that geese were able to use uncommon feedstuffs with high digestibility, and there was a significant negative correlation between energy digestibility and CF content. The ME values tested in this experiment can provide a foundation for preparation and adjustment of feed formulation for reasonable use of uncommon feedstuffs for geese. PMID:23776268

  11. Enzymatic Digestion for Improved Bacteria Separation from Leafy Green Vegetables.

    PubMed

    Wang, Danhui; Wang, Ziyuan; He, Fei; Kinchla, Amanda J; Nugen, Sam R

    2016-08-01

    An effective and rapid method for the separation of bacteria from food matrix remains a bottleneck for rapid bacteria detection for food safety. Bacteria can strongly attach to a food surface or internalize within the matrix, making their isolation extremely difficult. Traditional methods of separating bacteria from food routinely involve stomaching, blending, and shaking. However, these methods may not be efficient at removing all the bacteria from complex matrices. Here, we investigate the benefits of using enzyme digestion followed by immunomagnetic separation to isolate Salmonella from spinach and lettuce. Enzymatic digestion using pectinase and cellulase was able to break down the structure of the leafy green vegetables, resulting in the detachment and release of Salmonella from the leaves. Immunomagnetic separation of Salmonella from the liquefied sample allowed an additional separation step to achieve a more pure sample without leaf debris that may benefit additional downstream applications. We have investigated the optimal combination of pectinase and cellulase for the digestion of spinach and lettuce to improve sample detection yields. The concentrations of enzymes used to digest the leaves were confirmed to have no significant effect on the viability of the inoculated Salmonella. Results reported that the recovery of the Salmonella from the produce after enzyme digestion of the leaves was significantly higher (P < 0.05) than traditional sample preparation methods to separate bacteria (stomaching and manually shaking). The results demonstrate the potential for use of enzyme digestion prior to separation can improve the efficiency of bacteria separation and increase the likelihood of detecting pathogens in the final detection assay. PMID:27497125

  12. Improved anaerobic digestion by staged fermentation and advanced reactor design

    SciTech Connect

    Ghosh, S.; Bostian, H.E.; Henry, M.P.; Sajjad, A.; Farrell, J.B.; Salotto, B.V.

    1985-01-01

    The anaerobic digestion process has taken on new importance and emphasis in recent years because of its potential applications for energy and chemicals production from various types of renewable-carbon resources, and because it can be coupled with certain electrochemical, thermochemical, and biochemical processes to generate electric power, hydrocarbons, methanol, and other high-value products. A number of initiatives have been taken to improve the anaerobic digestion process in keeping with the increasing appreciation for its utility and versatility of application in municipal, industrial, and rural settings.

  13. Detoxifying CO2 capture reclaimer waste by anaerobic digestion.

    PubMed

    Wang, Shuai; Hovland, Jon; Brooks, Steven; Bakke, Rune

    2014-01-01

    The decrease in toxicity of carbon capture reclaimer monoethanolamine (MEA) waste (MEAw) during anaerobic degradation of such waste together with easily degradable organics was investigated. Samples were collected from a bioreactor at steady state with 86 % organic chemical oxygen demand removal at room temperature, which had been running on MEAw for 2 years. The toxicity of the digester effluents were 126, 42 and 10 times lower than that of the MEAw to the tested freshwater trophic groups of Pseudokirchneriella subcapitata, Daphnia magna and embryos of Danio rerio, respectively. The toxicity of the tested taxonomic groups after anaerobic digestion was mainly attributed to the ammonia generated by the degradation of MEAw. PMID:24122630

  14. Biogas production from anaerobic digestion of Spirulina maxima algal biomass

    SciTech Connect

    Rejean Samson; Anh LeDuy

    1982-08-01

    Spirulina maxima algal biomass could be used as the sole nutrient for the production of biogas by anaerobic digestion process. It is relatively simple to adapt the municipal sewage sludge to this new substrate. The adapted sludge is very stable. Under nonoptimal conditions, the methane yield and productivity obtained were 0.26 m/sup 3//(kg VS added day) and 0.26 m/sup 3//(kg VS added day), respectively, with the semicontinuous, daily fed, anaerobic digestion having loading rate of 0.97 kg VS/(m/sup 3/ day), retention time of 33 days and temperature of 30/sup 0/C.

  15. Genetic Analysis of Digestive Physiology Using Fluorescent Phospholipid Reporters

    NASA Astrophysics Data System (ADS)

    Farber, Steven A.; Pack, Michael; Ho, Shiu-Ying; Johnson, Iain D.; Wagner, Daniel S.; Dosch, Roland; Mullins, Mary C.; Hendrickson, H. Stewart; Hendrickson, Elizabeth K.; Halpern, Marnie E.

    2001-05-01

    Zebrafish are a valuable model for mammalian lipid metabolism; larvae process lipids similarly through the intestine and hepatobiliary system and respond to drugs that block cholesterol synthesis in humans. After ingestion of fluorescently quenched phospholipids, endogenous lipase activity and rapid transport of cleavage products results in intense gall bladder fluorescence. Genetic screening identifies zebrafish mutants, such as fat free, that show normal digestive organ morphology but severely reduced phospholipid and cholesterol processing. Thus, fluorescent lipids provide a sensitive readout of lipid metabolism and are a powerful tool for identifying genes that mediate vertebrate digestive physiology.

  16. [Training in digestive endoscopy. Considerations, experiences and methodological contributions].

    PubMed

    Santos Lucero, R; Espiniella, F; Zárate, J O; Tomás, J; Grosso, M

    1986-01-01

    The bibliographical contributions on education in digestive endoscopy and the need of establishing in Argentina a curricular programming for its teaching-learning are considered. The experience of the authors acquired during the giving of eight Basic or initiation Courses and eight Advanced or Improvement Courses is presented. They used in them six didactic simulators and endoscopic cinematography that completed the written simulations. Conceptual and methodological aspects are exposed to perform the curricular programming of training comprising the student from the student of Medicine to the gastroenterologist or surgeon more devoted or specialist in digestive endoscopy. PMID:3661076

  17. Anaerobic digestion of food waste - Effect of recirculation and temperature on performance and microbiology.

    PubMed

    Zamanzadeh, Mirzaman; Hagen, Live H; Svensson, Kine; Linjordet, Roar; Horn, Svein J

    2016-06-01

    Recirculation of digestate was investigated as a strategy to dilute the food waste before feeding to anaerobic digesters, and its effects on microbial community structure and performance were studied. Two anaerobic digesters with digestate recirculation were operated at 37 °C (MD + R) and 55 °C (TD + R) and compared to two additional digesters without digestate recirculation operated at the same temperatures (MD and TD). The MD + R digester demonstrated quite stable and similar performance to the MD digester in terms of the methane yield (around 480 mL CH4 per gVSadded). In both MD and MD + R Methanosaeta was the dominant archaea. However, the bacterial community structure was significantly different in the two digesters. Firmicutes dominated in the MD + R, while Chloroflexi was the dominant phylum in the MD. Regarding the thermophilic digesters, the TD + R showed the lowest methane yield (401 mL CH4 per gVSadded) and accumulation of VFAs. In contrast to the mesophilic digesters, the microbial communities in the thermophilic digesters were rather similar, consisting mainly of the phyla Firmicutes, Thermotoga, Synergistetes and the hydrogenotrophic methanogen Methanothermobacter. The impact of ammonia inhibition was different depending on the digesters configurations and operating temperatures. PMID:27060528

  18. Effect of temperature on methane production from field-scale anaerobic digesters treating dairy manure.

    PubMed

    Arikan, Osman A; Mulbry, Walter; Lansing, Stephanie

    2015-09-01

    Temperature is a critical factor affecting anaerobic digestion because it influences both system heating requirements and methane production. Temperatures of 35-37°C are typically suggested for manure digestion. In temperate climates, digesters require a considerable amount of additional heat energy to maintain temperatures at these levels. In this study, the effects of lower digestion temperatures (22 and 28°C), on the methane production from dairy digesters were evaluated and compared with 35°C using duplicate replicates of field-scale (FS) digesters with a 17-day hydraulic retention time. After acclimation, the FS digesters were operated for 12weeks using solids-separated manure at an organic loading rate (OLR) of 1.4kgVSm(-3)d(-1) and then for 8weeks using separated manure amended with manure solids at an OLR of 2.6kgVSm(-3)d(-1). Methane production values of the FS digesters at 22 and 28°C were about 70% and 87%, respectively, of the values from FS digesters at 35°C. The results suggest that anaerobic digesters treating dairy manure at 28°C were nearly as efficient as digesters operated at 35°C, with 70% of total methane achievable at 22°C. These results are relevant to small farms interested in anaerobic digestion for methane reduction without heat recovery from generators or for methane recovery from covered lagoon digesters. PMID:26101200

  19. Micro-quantity tissue digestion for metal measurements by use of a microwave acid-digestion bomb.

    PubMed

    Nicholson, J R; Savory, M G; Savory, J; Wills, M R

    1989-03-01

    We describe a simple and convenient method for processing small amounts of tissue samples for trace-metal measurements by atomic absorption spectrometry, by use of a modified Parr microwave digestion bomb. Digestion proceeds rapidly (less than or equal to 90 s) in a sealed Teflon-lined vessel that eliminates contamination or loss from volatilization. Small quantities of tissue (5-100 mg dry weight) are digested in high-purity nitric acid, yielding concentrations of analyte that can be measured directly without further sample manipulation. We analyzed National Institute of Standards and Technology bovine liver Standard Reference Material to verify the accuracy of the technique. We assessed the applicability of the technique to analysis for aluminum in bone by comparison with a dry ashing procedure. PMID:2537690

  20. Anaerobic digester foaming in full-scale cylindrical digesters--effects of organic loading rate, feed characteristics, and mixing.

    PubMed

    Subramanian, Bhargavi; Pagilla, Krishna R

    2014-05-01

    Cylindrical anaerobic digesters (AD) were investigated to determine the causes and contributors of AD foaming due to the following: organic loading rate (OLR) and mixing effects, waste activated sludge (WAS) storage effects and foam suppression mixing at the surface of AD, and the effects of primary sludge (PS) solids fraction in the feed sludge. No foaming was observed over the duration of the study, indicating absence of a primary foaming cause even though the suspected contributors to AD foaming were present. Total solids and temperature profiles showed that reducing mixing frequency did not significantly impact digester performance or the homogeneity of the digester contents. The results showed that high organic loading rates, reduced mixing, and feed sludge storage by themselves do not cause foaming in most ADs when the primary foaming cause is absent. Reduced mixing and surface sludge sprays are practical strategies to control AD foaming. PMID:24650532

  1. Anaerobic digestion of pulp and paper mill wastewater and sludge.

    PubMed

    Meyer, Torsten; Edwards, Elizabeth A

    2014-11-15

    Pulp and paper mills generate large amounts of waste organic matter that may be converted to renewable energy in form of methane. The anaerobic treatment of mill wastewater is widely accepted however, usually only applied to few selected streams. Chemical oxygen demand (COD) removal rates in full-scale reactors range between 30 and 90%, and methane yields are 0.30-0.40 m(3) kg(-1) COD removed. Highest COD removal rates are achieved with condensate streams from chemical pulping (75-90%) and paper mill effluents (60-80%). Numerous laboratory and pilot-scale studies have shown that, contrary to common perception, most other mill effluents are also to some extent anaerobically treatable. Even for difficult-to-digest streams such as bleaching effluents COD removal rates range between 15 and 90%, depending on the extent of dilution prior to anaerobic treatment, and the applied experimental setting. Co-digestion of different streams containing diverse substrate can level out and diminish toxicity, and may lead to a more robust microbial community. Furthermore, the microbial population has the ability to become acclimated and adapted to adverse conditions. Stress situations such as toxic shock loads or temporary organic overloading may be tolerated by an adapted community, whereas they could lead to process disturbance with an un-adapted community. Therefore, anaerobic treatment of wastewater containing elevated levels of inhibitors or toxicants should be initiated by an acclimation/adaptation period that can last between a few weeks and several months. In order to gain more insight into the underlying processes of microbial acclimation/adaptation and co-digestion, future research should focus on the relationship between wastewater composition, reactor operation and microbial community dynamics. The potential for engineering and managing the microbial resource is still largely untapped. Unlike in wastewater treatment, anaerobic digestion of mill biosludge (waste activated

  2. Investigation of Poultry Waste for Anaerobic Digestion: A Case Study

    NASA Astrophysics Data System (ADS)

    Salam, Christopher R.

    Anaerobic Digestion (AD) is a biological conversion technology which is being used to produce bioenergy all over the world. This energy is created from biological feedstocks, and can often use waste products from various food and agricultural processors. Biogas from AD can be used as a fuel for heating or for co-generation of electricity and heat and is a renewable substitute to using fossil fuels. Nutrient recycling and waste reduction are additional benefits, creating a final product that can be used as a fertilizer in addition to energy benefits. This project was conducted to investigate the viability of three turkey production wastes as AD feedstock: two turkey litters and a material separated from the turkey processing wastewater using dissolved air flotation (DAF) process. The DAF waste contained greases, oils and other non-commodity portions of the turkey. Using a variety of different process methods, types of bacteria, loading rates and food-to-microorganism ratios, optimal loading rates for the digestion of these three materials were obtained. In addition, the co-digestion of these materials revealed additional energy benefits. In this study, batch digestion tests were carried out to treat these three feedstocks, using mesophilic and thermophilic bacteria, using loading rates of 3 and 6 gVS/L They were tested separately and also as a mixture for co-digestion. The batch reactor used in this study had total and working volumes of 1130 mL and 500 mL, respectively. The initial organic loading was set to be 3 gVS/L, and the food to microorganism ratio was either 0.6 or 1.0 for different treatments based on the characteristics of each material. Only thermophilic (50 +/- 2ºC) temperatures were tested for the litter and DAF wastes in continuous digestion, but mesophilic and thermophilic batch digestion experiments were conducted. The optimum digestion time for all experiments was 14 days. The biogas yields of top litter, mixed litter, and DAF waste under

  3. 77 FR 53208 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-31

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases, including consideration of personnel qualifications and performance, and the competence..., National Institute of Diabetes and Digestive and Kidney Diseases, National Institute of Health, Building...

  4. 78 FR 58325 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-23

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases Special Emphasis Panel, Bariatric Surgery-- Related Ancillary Studies (R01s). Date... Digestive and Kidney Diseases Special Emphasis Panel, Regulatory Mechanisms in Intestinal Motility...

  5. 77 FR 28890 - National Institute of Diabetes and Digestive and Kidney Diseases Notice of Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-16

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases Initial Review Group; Kidney, Urologic and Hematologic Diseases D Subcommittee. Date... . Name of Committee: National Institute of Diabetes and Digestive and Kidney Diseases Initial...

  6. 75 FR 9231 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-01

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases Special Emphasis Panel; Metabolic Dysfunction Collaborative Interdisciplinary Science... Diabetes and Digestive and Kidney Diseases Special Emphasis Panel; CAMUS Trial. Date: April 2, 2010....

  7. 75 FR 9911 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-04

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases Special Emphasis Panel, Seeding Team Science in Diabetes Endocrinology and Metabolic... of Committee: National Institute of Diabetes and Digestive and Kidney Diseases Special Emphasis...

  8. 78 FR 28859 - National Institute of Diabetes and Digestive and Kidney Diseases Notice of Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-16

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... and Kidney Diseases Initial Review Group; Diabetes, Endocrinology and Metabolic Diseases B... Committee: National Institute of Diabetes and Digestive and Kidney Diseases Initial Review Group;...

  9. 78 FR 9063 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-07

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases Initial Review Group; Kidney, Urologic and Hematologic Diseases D Subcommittee. Date... . Name of Committee: National Institute of Diabetes and Digestive and Kidney Diseases Initial...

  10. 75 FR 65365 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-22

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases Special Emphasis Panel, Genetics of Nephropathy Ancillary Studies. Date: November 15... Digestive and Kidney Diseases Special Emphasis Panel, Consortium for Radiologic Imaging Studies...

  11. 75 FR 14605 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-26

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases, including consideration of personnel qualifications and performance, and the competence..., Director, Division of Intramural Research, National Institute of Diabetes and Digestive and Kidney...

  12. 75 FR 3741 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-22

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases Initial Review Group; Kidney, Urologic and Hematologic Diseases D Subcommittee. Date... . Name of Committee: National Institute of Diabetes and Digestive and Kidney Diseases Initial...

  13. ENGINEERING AND ECONOMIC ASSESSMENT OF AUTOHEATED THERMOPHILIC AEROBIC DIGESTION WITH AIR AERATION

    EPA Science Inventory

    A major disadvantage of aerobic digestion is that it requires long detention times, particularly in colder climates, to insure adequate stabilization. Autoheated thermophilic aerobic digestion (ATAD) offers the potential to decrease the required detention time. ATAD takes advanta...

  14. Comparison of mesophilic and thermophilic anaerobic digestion of sugar beet pulp: performance, dewaterability and foam control.

    PubMed

    Suhartini, Sri; Heaven, Sonia; Banks, Charles J

    2014-01-01

    Digestion of sugar beet pulp was assessed in relation to biogas and methane production, foaming potential, and digestate dewaterability. Four 4-litre working volume digesters were operated mesophilically (37±0.5 °C) and four thermophilically (55±0.5 °C) over three hydraulic retention times. Digesters were operated in duplicate at organic loading rates (OLR) of 4 and 5 g volatile solids l(-1) day(-1) without water addition. Thermophilic digestion gave higher biogas and methane productivity than mesophilic and was able to operate at the higher OLR, where mesophilic digestion showed signs of instability. Digestate dewaterability was assessed using capillary suction time and frozen image centrifugation. The occurrence of, or potential for, stable foam formation was assessed using a foaming potential test. Thermophilic operation allowed higher loadings to be applied without loss of performance, and gave a digestate with superior dewatering characteristics and very little foaming potential. PMID:24291796

  15. Galled by the Gallbladder?: Your Tiny, Hard-Working Digestive Organ

    MedlinePlus

    ... Galled by the Gallbladder? Your Tiny, Hard-Working Digestive Organ Most of us give little thought to ... among the most common and costly of all digestive system diseases. By some estimates, up to 20 ...

  16. Stability and Immunogenicity of Hypoallergenic Peanut Protein-Polyphenol Complexes During In Vitro Pepsin Digestion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Allergenic peanut proteins are relatively resistant to digestion, and if digested, metabolized peptides tend to remain large and immunoreactive, triggering allergic reactions in sensitive individuals. In this study, the stability of hypoallergenic peanut protein-polyphenol complexes was evaluated d...

  17. 78 FR 19275 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-29

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases, including consideration of personnel qualifications and performance, and the competence..., National Institute of Diabetes and Digestive, and Kidney Diseases, National Institute of Health, Building...

  18. Different digestion of caprine whey proteins by human and porcine gastrointestinal enzymes.

    PubMed

    Eriksen, Ellen K; Holm, Halvor; Jensen, Einar; Aaboe, Ragnhild; Devold, Tove G; Jacobsen, Morten; Vegarud, Gerd E

    2010-08-01

    The objective of the present study was twofold: first to compare the degradation patterns of caprine whey proteins digested with either human digestive juices (gastric or duodenal) or commercial porcine enzymes (pepsin or pancreatic enzymes) and second to observe the effect of gastric pH on digestion. An in vitro two-step assay was performed at 37 degrees C to simulate digestion in the stomach (pH 2, 4 or 6) and the duodenum (pH 8). The whey proteins were degraded more efficiently by porcine pepsin than by human gastric juice at all pH values. Irrespective of the enzyme source, gastric digestion at pH 2 followed by duodenal digestion resulted in the most efficient degradation. Lactoferrin, serum albumin and the Ig heavy chains were highly degraded with less than 6 % remaining after digestion. About 15, 56 and 50 % Ig light chains, beta-lactoglobulin (beta-LG) and alpha-lactalbumin remained intact, respectively, when digested with porcine enzymes compared with 25, 74 and 81 % with human digestive juices. For comparison, purified bovine beta-LG was digested and the peptide profiles obtained were compared with those of the caprine beta-LG in the digested whey. The bovine beta-LG seemed to be more extensively cleaved than the caprine beta-LG in the whey. Commercial enzymes appear to digest whey proteins more efficiently compared with human digestive juices when used at similar enzyme activities. This could lead to conflicting results when comparing human in vivo protein digestion with digestion using purified enzymes of non-human species. Consequently the use of human digestive juices might be preferred. PMID:20307348

  19. Helping Young Children Deal with Anger. ERIC Digest.

    ERIC Educational Resources Information Center

    Marion, Marian

    Children's anger presents challenges to teachers committed to constructive, ethical, and effective child guidance. This Digest explores what is known about the components of children's anger, factors contributing to understanding and managing anger, and the ways teachers can guide children's expressions of anger. Anger is believed to have three…

  20. How Minority Students Finance Their Higher Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Nora, Amaury

    This digest examines the various financial sources minority students use to meet the costs of higher education, some of which were created with the specific goal of promoting their college attendance. Sources include federal student loans, pre-college programs and grants, college prepaid plans, and student credit cards. Policy recommendations to…