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Sample records for biodegradation current advances

  1. Current trends in trichloroethylene biodegradation: a review.

    Science.gov (United States)

    Shukla, Awadhesh Kumar; Upadhyay, Siddh Nath; Dubey, Suresh Kumar

    2014-06-01

    Over the past few years biodegradation of trichloroethylene (TCE) using different microorganisms has been investigated by several researchers. In this review article, an attempt has been made to present a critical summary of the recent results related to two major processes--reductive dechlorination and aerobic co-metabolism used for TCE biodegradation. It has been shown that mainly Clostridium sp. DC-1, KYT-1, Dehalobacter, Dehalococcoides, Desulfuromonas, Desulfitobacterium, Propionibacterium sp. HK-1, and Sulfurospirillum bacterial communities are responsible for the reductive dechlorination of TCE. Efficacy of bacterial communities like Nitrosomonas, Pseudomonas, Rhodococcus, and Xanthobacter sp. etc. for TCE biodegradation under aerobic conditions has also been examined. Mixed cultures of diazotrophs and methanotrophs have been used for TCE degradation in batch and continuous cultures (biofilter) under aerobic conditions. In addition, some fungi (Trametes versicolor, Phanerochaete chrysosporium ME-446) and Actinomycetes have also been used for aerobic biodegradation of TCE. The available information on kinetics of biofiltration of TCE and its degradation end-products such as CO2 are discussed along with the available results on the diversity of bacterial community obtained using molecular biological approaches. It has emerged that there is a need to use metabolic engineering and molecular biological tools more intensively to improve the robustness of TCE degrading microbial species and assess their diversity.

  2. Advances in Biodegradation of Multiple Volatile Organic Compounds

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    Zhang, M.; Yoshikawa, M.

    2017-12-01

    Bioremediation of soil and groundwater containing multiple contaminants remains a challenge in environmental science and engineering because complete biodegradation of all components is necessary but very difficult to accomplish in practice. This presentation provides a brief overview on advances in biodegradation of multiple volatile organic compounds (VOCs) including chlorinated ethylenes, benzene, toluene and dichloromethane (DCM). Case studies on aerobic biodegradation of benzene, toluene and DCM, and integrated anaerobic-aerobic biodegradation of 7 contaminants, specifically, tetrachloroethylene (PCE), trichloroethylene (TCE), cis-dichloroethylene (cis-DCE), vinyl chloride (VC), DCM, benzene and toluene will be provided. Recent findings based on systematic laboratory experiments indicated that aerobic toluene degradation can be enhanced by co-existence of benzene. Propioniferax, not a known benzene, toluene and DCM degrader can be a key microorganism that involves in biodegradation when the three contaminants co-exist. Integrated anaerobic-aerobic biodegradation is capable of completely degrading the seven VOCs with initial concentrations less than 30 mg/L. Dehalococcoides sp., generally considered sensitive to oxygen, can survive aerobic conditions for at least 28 days, and can be activated during the subsequent anaerobic biodegradation. This presentation may provide a systematic information about biodegradation of multiple VOCs, and a scientific basis for the complete bioremediation of multiple contaminants in situ.

  3. Current knowledge on biodegradable microspheres in drug delivery.

    Science.gov (United States)

    Prajapati, Vipul D; Jani, Girish K; Kapadia, Jinita R

    2015-08-01

    Biodegradable microspheres have gained popularity for delivering a wide variety of molecules via various routes. These types of products have been prepared using various natural and synthetic biodegradable polymers through suitable techniques for desired delivery of various challenging molecules. Selection of biodegradable polymers and technique play a key role in desired drug delivery. This review describes an overview of the fundamental knowledge and status of biodegradable microspheres in effective delivery of various molecules via desired routes with consideration of outlines of various compendial and non-compendial biodegradable polymers, formulation techniques and release mechanism of microspheres, patents and commercial biodegradable microspheres. There are various advantages of using biodegradable polymers including promise of development with different types of molecules. Biocompatibility, low dosage and reduced side effects are some reasons why usage biodegradable microspheres have gained in popularity. Selection of biodegradable polymers and formulation techniques to create microspheres is the biggest challenge in research. In the near future, biodegradable microspheres will become the eco-friendly product for drug delivery of various genes, hormones, proteins and peptides at specific site of body for desired periods of time.

  4. Interactive association between biopolymers and biofunctions in carinata seeds as energy feedstock and their coproducts (carinata meal) from biofuel and bio-oil processing before and after biodegradation: current advanced molecular spectroscopic investigations.

    Science.gov (United States)

    Yu, Peiqiang; Xin, Hangshu; Ban, Yajing; Zhang, Xuewei

    2014-05-07

    Recent advances in biofuel and bio-oil processing technology require huge supplies of energy feedstocks for processing. Very recently, new carinata seeds have been developed as energy feedstocks for biofuel and bio-oil production. The processing results in a large amount of coproducts, which are carinata meal. To date, there is no systematic study on interactive association between biopolymers and biofunctions in carinata seed as energy feedstocks for biofuel and bioethanol processing and their processing coproducts (carinata meal). Molecular spectroscopy with synchrotron and globar sources is a rapid and noninvasive analytical technique and is able to investigate molecular structure conformation in relation to biopolymer functions and bioavailability. However, to date, these techniques are seldom used in biofuel and bioethanol processing in other research laboratories. This paper aims to provide research progress and updates with molecular spectroscopy on the energy feedstock (carinata seed) and coproducts (carinata meal) from biofuel and bioethanol processing and show how to use these molecular techniques to study the interactive association between biopolymers and biofunctions in the energy feedstocks and their coproducts (carinata meal) from biofuel and bio-oil processing before and after biodegradation.

  5. Biodegradation of plastics: current scenario and future prospects for environmental safety.

    Science.gov (United States)

    Ahmed, Temoor; Shahid, Muhammad; Azeem, Farrukh; Rasul, Ijaz; Shah, Asad Ali; Noman, Muhammad; Hameed, Amir; Manzoor, Natasha; Manzoor, Irfan; Muhammad, Sher

    2018-03-01

    Plastic is a general term used for a wide range of high molecular weight organic polymers obtained mostly from the various hydrocarbon and petroleum derivatives. There is an ever-increasing trend towards the production and consumption of plastics due to their extensive industrial and domestic applications. However, a wide spectrum of these polymers is non-biodegradable with few exceptions. The extensive use of plastics, lack of waste management, and casual community behavior towards their proper disposal pose a significant threat to the environment. This has raised growing concerns among various stakeholders to devise policies and innovative strategies for plastic waste management, use of biodegradable polymers especially in packaging, and educating people for their proper disposal. Current polymer degradation strategies rely on chemical, thermal, photo, and biological procedures. In the presence of proper waste management strategies coupled with industrially controlled biodegradation facilities, the use of biodegradable plastics for some applications such as packaging or health industry is a promising and attractive option for economic, environmental, and health benefits. This review highlights the classification of plastics with special emphasis on biodegradable plastics and their rational use, the identified mechanisms of plastic biodegradation, the microorganisms involved in biodegradation, and the current insights into the research on biodegradable plastics. The review has also identified the research gaps in plastic biodegradation followed by future research directions.

  6. Comparative evaluation of anaerobic biodegradability of hydrocarbons and fatty derivatives currently used as drilling fluids.

    Science.gov (United States)

    Steber, J; Herold, C P; limia, J M

    1995-08-01

    The examination of a number of potential and currently used carrier fluids for invert emulsion drilling fluids in the ECETOC screening test revealed clear differences with respect to their easy anaerobic biodegradability. Fatty acid- and alcohol-based ester oils exhibited excellent anaerobic degradation to the gaseous final end products of the methanogenic degradation pathway, methane and carbon dioxide. Mineral oils, dialkyl ethers, alpha-olefins, polyalphaolefins, linear alkylbenzenes and an acetal-derivative were not or only slowly degraded. Although the poor degradation results obtained in the stringent ECETOC screening test may not be regarded as final proof of anaerobic recalcitrance, nevertheless, these results were found to be in line with the present understanding of the structural requirements for anaerobic biodegradability of chemicals. The validity of the conclusions drawn is corroborated by published results on the anaerobic biodegradation behaviour of ester oils, mineral oils and alkylbenzenes in marine sediments.

  7. Current advances in seismic technology

    International Nuclear Information System (INIS)

    Sherwood, J.R.

    1996-01-01

    Recent advances in seismic technology that impact on the estimation of reserves and reduction in risks associated with reserves estimates, were discussed. It was noted that seismic data along with subsurface geological and engineering data is a powerful tool that has applications to interpret the petroleum system and the reserves associated with that system. For example, seismic data can be used to define the location of reserves and to show results of drilling activity. Other reserve parameters that can be estimated using seismic tools are: area, thickness, porosity, saturation, recovery factor, and formation volume factor. Two case histories where seismic techniques were used for reserves estimation were described

  8. Current advances in liver surgery

    Directory of Open Access Journals (Sweden)

    Shannon Melissa Chan

    2015-01-01

    Full Text Available Hepatobiliary surgery has taken a big step forward in recent decades especially in the minimally invasive approach for hepatectomy. From being sceptical at the beginning of the 1990s when laparoscopic surgery had become prevalent, to now, where laparoscopic hepatectomy has been well-established, especially in minor hepatectomies; this new technique has evolved rapidly over the past 20-years demonstrating better short-term outcomes and equivalent oncological outcomes in selected patients and in expert hands. Laparoscopic hepatectomy is indeed, more difficult to master than the open procedure with restrictions in working space, difficulty in haemostasis and the potential risk of gas embolism. However, with better visibility of the operative field around the liver, especially beneath the costal margin, the magnified view and theoretical advantage of pneumoperitoneum acting as haemostatic pressure have made laparoscopic hepatectomy increasingly popular. Another important advancement is the new surgical technique of associating liver partition and portal vein ligation for staged hepatectomy (ALPPS. This procedure induces more rapid liver hypertrophy within a median period of 9-days, allowing resection to be performed in candidates with borderline functional liver remnant and at an earlier date. However, studies have shown that ALPPS is associated with a relatively higher rate of morbidity and mortality. Therefore, it remains a highly controversial treatment option and more studies have to be performed to establish its usefulness and define its role in liver surgery.

  9. Current advances in orthodontic pain.

    Science.gov (United States)

    Long, Hu; Wang, Yan; Jian, Fan; Liao, Li-Na; Yang, Xin; Lai, Wen-Li

    2016-06-30

    Orthodontic pain is an inflammatory pain that is initiated by orthodontic force-induced vascular occlusion followed by a cascade of inflammatory responses, including vascular changes, the recruitment of inflammatory and immune cells, and the release of neurogenic and pro-inflammatory mediators. Ultimately, endogenous analgesic mechanisms check the inflammatory response and the sensation of pain subsides. The orthodontic pain signal, once received by periodontal sensory endings, reaches the sensory cortex for pain perception through three-order neurons: the trigeminal neuron at the trigeminal ganglia, the trigeminal nucleus caudalis at the medulla oblongata and the ventroposterior nucleus at the thalamus. Many brain areas participate in the emotion, cognition and memory of orthodontic pain, including the insular cortex, amygdala, hippocampus, locus coeruleus and hypothalamus. A built-in analgesic neural pathway-periaqueductal grey and dorsal raphe-has an important role in alleviating orthodontic pain. Currently, several treatment modalities have been applied for the relief of orthodontic pain, including pharmacological, mechanical and behavioural approaches and low-level laser therapy. The effectiveness of nonsteroidal anti-inflammatory drugs for pain relief has been validated, but its effects on tooth movement are controversial. However, more studies are needed to verify the effectiveness of other modalities. Furthermore, gene therapy is a novel, viable and promising modality for alleviating orthodontic pain in the future.

  10. Evaluation of the biodegradability and toxicity of landfill leachates after pretreatment using advanced oxidative processes.

    Science.gov (United States)

    da Costa, Fabio Moraes; Daflon, Sarah Dario Alves; Bila, Daniele Maia; da Fonseca, Fabiana Valeria; Campos, Juacyara Carbonelli

    2018-02-19

    Leachate from urban solid waste landfills is a complex mixture of organic and inorganic substances that cause damage to the environment, due to the high concentration of recalcitrant organic matter and toxicity. The objective of this study was to apply advanced oxidation processes (AOP), namely the dark Fenton and solar photo-Fenton processes, to young and old landfill leachates prior to biological treatment. The leachates were obtained from the Seropedica and Gramacho landfill sites, respectively, located in Rio de Janeiro State, Brazil. For the two Fenton processes, different conditions of pH (1.5, 3.0 and 5.0) and Fe 2+ : H 2 O 2 ratio (1:2, 1:5 and 1:10) were evaluated. Biodegradability was evaluated using the Zahn-Wellens methodology and Aliivibrio fischeri acute toxicity tests were conducted in order to predict the toxicity in the activated sludge. The best conditions for both Fenton processes were pH of 3.0 and Fe 2+ : H 2 O 2 and COD RAW :H 2 O 2 mass ratios of 1:5 and 1:1, respectively. The solar photo-Fenton process was more effective at improving the quality for both leachates, reaching COD, TOC and abs 254 nm reductions of 82%, 85% and 96.3%, respectively, for the Seropedica landfill leachate. In the case of the Gramacho landfill leachate, the corresponding reductions were 78.2, 80.7% and 91.1%, respectively. The biodegradability results for the untreated leachates from the Seropedica and Gramacho sites were 65% and 30% respectively. The biodegradability of both leachates was improved by the Fenton processes, especially the solar photo-Fenton process, which increased the leachate biodegradability to 89% (Seropedica) and 69% (Gramacho). For both leachates, a greater reduction in the acute toxicity was achieved with the solar photo-Fenton compared to the dark-Fenton process. The Seropedica landfill leachate showed high toxicity (EC50 = 33%, 15 min), after the dark Fenton and solar photo Fenton processes, with EC50 values of 81 and 91

  11. Alternating-current electrophoretic adhesion of biodegradable hydrogel utilizing intermediate polymers.

    Science.gov (United States)

    Asoh, Taka-Aki; Kawai, Wataru; Kikuchi, Akihiko

    2014-11-01

    The adhesion of anionic charged biodegradable hydrogels each other utilizing oppositely charged water-soluble polymers as a binder has been achieved by applying alternating-current (AC) electric fields. The two gelatin based dextran sulfate gels (DS gels) were molecularly sutured together by AC electrophoretic adhesion when cationic charged quaternary ammonium chitosan (TMC) was applied between and held in contact with the two DS gels. The adhesive strength of the gels increased with increasing periodicity when a square wave was applied. Hydrogel constructs composed of DS microgels were prepared simply by AC electrophoretic adhesion utilizing intermediate TMC. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Current status and future direction of biodegradable metallic and polymeric vascular scaffolds for next-generation stents.

    Science.gov (United States)

    Im, Seung Hyuk; Jung, Youngmee; Kim, Soo Hyun

    2017-09-15

    Because of the increasing incidence of coronary artery disease, the importance of cardiovascular stents has continuously increased as a treatment of this disease. Biodegradable scaffolds fabricated from polymers and metals have emerged as promising materials for vascular stents because of their biodegradability. Although such stent framework materials have shown good clinical efficacy, it is difficult to decide whether polymers or metals are better vascular scaffolds because their properties are different. Therefore, there are still obstacles in the development of biodegradable vascular scaffolds in terms of improving clinical efficacy. This review analyzes the pros and cons of current stent materials with respect to five key factors for next-generation stent and discusses methods of improvement. Furthermore, we discuss biodegradable electronic stents with electrical conductivity, which has been considered unimportant until now, and highlight electrical conductivity as a key factor in the development of next-generation stents. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  13. Current advances in neutron diffraction stress measurement

    International Nuclear Information System (INIS)

    Suzuki, Hiroshi; Tomota, Yo

    2007-01-01

    Neutron diffraction has been employed for stress evaluation of various mechanical components. The hkl lattice plane spacings in a diffraction gauge volume are measured, then elastic strains are calculated and finally stresses are determined by using the Hooke's law. Since the real engineering mechanical parts are so complicated that more sophisticated method must be progressed to obtain stress distribution in the inside of a sample. Current advances on this issue are reviewed. (author)

  14. Advances on the Use of Biodegradable Proteins/Peptides in Photothermal Theranostics

    Directory of Open Access Journals (Sweden)

    Sheng Wang

    2016-01-01

    Full Text Available Recently, photothermal therapy (PTT which employs light-induced heating to destroy cancer tissues/cells has received tremendous attention due to its improved selectivity and minimal invasion to surrounding healthy tissues. A variety of photothermal conversion agents (PTCAs with high near-infrared (NIR light absorbance have been widely explored for NIR light-induced PTT. However, many of them cannot be used directly in vivo owing to their nonbiodegradability, immunogenicity, poor pharmacokinetics, or potential long-term toxicity. Proteins and peptides with inherent biocompatibility and biodegradability have been used as delivery vehicles for PTCAs or used as biotemplates to direct the synthesis of PTCAs. In this review, we will summarize recent advances in the development of protein/peptide-based photothermal cancer theranostics. The perspectives and challenges of these nanoplatforms will also be discussed.

  15. Recommendation for modifying current cytotoxicity testing standards for biodegradable magnesium-based materials.

    Science.gov (United States)

    Wang, Jiali; Witte, Frank; Xi, Tingfei; Zheng, Yufeng; Yang, Ke; Yang, Yuansheng; Zhao, Dewei; Meng, Jian; Li, Yangde; Li, Weirong; Chan, Kaiming; Qin, Ling

    2015-07-01

    As one of the most promising medical metal implants, magnesium (Mg) or its alloys have shown significant advantages over other candidates attributed to not only their excellent biodegradability and suitable mechanical properties but also their osteopromotive effects for bone applications. Prior to approval mandated by the governmental regulatory body, the access to the medical market for Mg-based implants requires a series of testing for assurance of their safety and efficacy via preclinical evaluations and clinical tests including phase 1 and 2 evaluations, and phase 3 of multi-center randomized double blind and placebo-controlled clinical trials. However, as the most widely used protocols for biosafety evaluation of medical devices, current ISO 10993 standards should be carefully reevaluated when directly applying them to predict potential health risks of degradable Mg based biomaterials via cytotoxicity tests due to the huge gap between in vitro and in vivo conditions. Therefore, instead of a direct adoption, modification of current ISO standards for in vitro cytotoxicity test is desirable and justified. The differences in sensitivities of cells to in vitro and in vivo Mg ions and the capability of in vivo circulation system to dilute local degradation products were fully considered to propose modification of current ISO standards. This paper recommended a minimal 6 times to a maximal 10 times dilution of extracts for in vitro cytotoxicity test specified in ISO 10993 part 5 for pure Mg developed as potential orthopedic implants based on literature review and our specifically designed in vitro and in vivo tests presented in the study. Our work may contribute to the progress of biodegradable metals involved translational work. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  16. Current deposition profiles in advanced geometries

    International Nuclear Information System (INIS)

    Wright, J.C.; Phillips, C.K.; Bonoli, P.T.

    1997-01-01

    In advanced toroidal devices, plasma shaping can have a significant effect on quantities of interest, including the radio frequency (RF) deposited power and current. Most 2D RF modeling codes use a parameterization of current drive efficiencies to calculate fast wave driven currents. This parameterization is derived from a ray-tracing model in a low-beta model equilibrium. There are difficulties in applying it to a spectrum of waves, and it cannot account for multiple resonances and coherency effects between the electrons and the waves. By evaluating a formulation of the quasilinear diffusion coefficient in an arbitrary inhomogenous geometry with the fields from a full wave code, we address the effects of wave spectra, plasma inhomogeneity, and plasma profile on the evaluation of current deposition profiles. Current profiles are calculated directly from the quasilinear diffusion using the adjoint formulation, with the magnetic equilibrium specified consistently in both the adjoint routine and the full wave code. Results are benchmarked by comparing a power deposition calculation from conductivity to one from the quasilinear expression. RF driven current profiles for various devices, including tokamaks with different aspect ratios, will be presented. copyright 1997 American Institute of Physics

  17. Mineralization and biodegradability enhancement of Methyl Orange dye by an effective advanced oxidation process

    International Nuclear Information System (INIS)

    Paul Guin, Jhimli; Bhardwaj, Y.K.; Varshney, Lalit

    2017-01-01

    An effective process for the oxidation of Methyl Orange dye (MO) was determined by comparing the mineralization efficiency between two advanced oxidation processes (AOPs) viz., ozonolysis and gamma radiolysis in presence and absence of an added inorganic salt potassium persulfate (K 2 S 2 O 8 ). The effects of various operating parameters such as ozone flow rate and reaction temperature were optimized to achieve the best possible mineralization extent of MO by ozonolysis. The mineralization efficiency of MO was significantly enhanced during gamma radiolysis in presence of K 2 S 2 O 8 (γ+K 2 S 2 O 8 ) compared to in absence of K 2 S 2 O 8 . The presence of methyl group at the amine of phenyl ring assisted the mineralization of dye during γ+K 2 S 2 O 8 . The oxygen-equivalent chemical-oxidation capacities (OCC) of ozonolysis and γ+K 2 S 2 O 8 for 75% mineralization of the dye solution were calculated as 7.008 and 0.0336 kg equiv. O 2 m −3 , respectively which signifies that γ+K 2 S 2 O 8 can be explored as an effective AOP. The non-biodegradable MO dye solution became biodegradable even after the dose of 0.5 kGy during γ+K 2 S 2 O 8 compared to 1 kGy in absence of K 2 S 2 O 8 . The study concludes that a lower dose γ+K 2 S 2 O 8 could be one of the efficient pretreatment steps before undergoing biological degradation of dye solution. - Highlights: • Systematic investigation was performed for the treatment of Methyl Orange dye solution. • AOPs investigated were ozonolysis and gamma radiolysis. • The OCC and % mineralizations of the AOPs were compared. • Gamma radiolysis in presence of K 2 S 2 O 8 was found as most effective AOP.

  18. Advances and current challenges in calcium signaling.

    Science.gov (United States)

    Kudla, Jörg; Becker, Dirk; Grill, Erwin; Hedrich, Rainer; Hippler, Michael; Kummer, Ursula; Parniske, Martin; Romeis, Tina; Schumacher, Karin

    2018-04-01

    Content Summary 414 I. Introduction 415 II. Ca 2+ importer and exporter in plants 415 III. The Ca 2+ decoding toolkit in plants 415 IV. Mechanisms of Ca 2+ signal decoding 417 V. Immediate Ca 2+ signaling in the regulation of ion transport 418 VI. Ca 2+ signal integration into long-term ABA responses 419 VII Integration of Ca 2+ and hormone signaling through dynamic complex modulation of the CCaMK/CYCLOPS complex 420 VIII Ca 2+ signaling in mitochondria and chloroplasts 422 IX A view beyond recent advances in Ca 2+ imaging 423 X Modeling approaches in Ca 2+ signaling 424 XI Conclusions: Ca 2+ signaling a still young blooming field of plant research 424 Acknowledgements 425 ORCID 425 References 425 SUMMARY: Temporally and spatially defined changes in Ca 2+ concentration in distinct compartments of cells represent a universal information code in plants. Recently, it has become evident that Ca 2+ signals not only govern intracellular regulation but also appear to contribute to long distance or even organismic signal propagation and physiological response regulation. Ca 2+ signals are shaped by an intimate interplay of channels and transporters, and during past years important contributing individual components have been identified and characterized. Ca 2+ signals are translated by an elaborate toolkit of Ca 2+ -binding proteins, many of which function as Ca 2+ sensors, into defined downstream responses. Intriguing progress has been achieved in identifying specific modules that interconnect Ca 2+ decoding proteins and protein kinases with downstream target effectors, and in characterizing molecular details of these processes. In this review, we reflect on recent major advances in our understanding of Ca 2+ signaling and cover emerging concepts and existing open questions that should be informative also for scientists that are currently entering this field of ever-increasing breath and impact. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

  19. Current Comparison of Advanced Fuel Cycle Options

    International Nuclear Information System (INIS)

    Steven J. Piet; B. W. Dixon; A. Goldmann; R. N. Hill; J. J. Jacobson; G. E. Matthern; J. D. Smith; A. M. Yacout

    2006-01-01

    The nuclear fuel cycle includes mining, enrichment, nuclear power plants, recycling (if done), and residual waste disposition. The U.S. Advanced Fuel Cycle Initiative (AFCI) has four program objectives to guide research on how best to glue these pieces together, as follows: waste management, proliferation resistance, energy recovery, and systematic management/economics/safety. We have developed a comprehensive set of metrics to evaluate fuel cycle options against the four program objectives. The current list of metrics is long-term heat, long-term dose, radiotoxicity and weapons usable material. This paper describes the current metrics and initial results from comparisons made using these metrics. The data presented were developed using a combination of ''static'' calculations and a system dynamic model, DYMOND. In many cases, we examine the same issue both dynamically and statically to determine the robustness of the observations. All analyses are for the U.S. reactor fleet. This work aims to clarify many of the issues being discussed within the AFCI program, including Inert Matrix Fuel (IMF) versus Mixed Oxide (MOX) fuel, single-pass versus multi-pass recycling, thermal versus fast reactors, and the value of separating cesium and strontium. The results from a series of dynamic simulations evaluating these options are included in this report. The model interface includes a few ''control knobs'' for flying or piloting the fuel cycle system into the future. The results from the simulations show that the future is dark (uncertain) and that the system is sluggish with slow time response times to changes (i.e., what types of reactors are built, what types of fuels are used, and the capacity of separation and fabrication plants). Piloting responsibilities are distributed among utilities, government, and regulators, compounding the challenge of making the entire system work and respond to changing circumstances. We identify four approaches that would increase our chances

  20. A Review on Recent Advances in Stabilizing Peptides/Proteins upon Fabrication in Hydrogels from Biodegradable Polymers

    Directory of Open Access Journals (Sweden)

    Faisal Raza

    2018-01-01

    Full Text Available Hydrogels evolved as an outstanding carrier material for local and controlled drug delivery that tend to overcome the shortcomings of old conventional dosage forms for small drugs (NSAIDS and large peptides and proteins. The aqueous swellable and crosslinked polymeric network structure of hydrogels is composed of various natural, synthetic and semisynthetic biodegradable polymers. Hydrogels have remarkable properties of functionality, reversibility, sterilizability, and biocompatibility. All these dynamic properties of hydrogels have increased the interest in their use as a carrier for peptides and proteins to be released slowly in a sustained manner. Peptide and proteins are remarkable therapeutic agents in today’s world that allow the treatment of severe, chronic and life-threatening diseases, such as diabetes, rheumatoid arthritis, hepatitis. Despite few limitations, hydrogels provide fine tuning of proteins and peptides delivery with enormous impact in clinical medicine. Novels drug delivery systems composed of smart peptides and molecules have the ability to drive self-assembly and form hydrogels at physiological pH. These hydrogels are significantly important for biological and medical fields. The primary objective of this article is to review current issues concerned with the therapeutic peptides and proteins and impact of remarkable properties of hydrogels on these therapeutic agents. Different routes for pharmaceutical peptides and proteins and superiority over other drugs candidates are presented. Recent advances based on various approaches like self-assembly of peptides and small molecules to form novel hydrogels are also discussed. The article will also review the literature concerning the classification of hydrogels on a different basis, polymers used, “release mechanisms” their physical and chemical characteristics and diverse applications.

  1. A Review on Recent Advances in Stabilizing Peptides/Proteins upon Fabrication in Hydrogels from Biodegradable Polymers.

    Science.gov (United States)

    Raza, Faisal; Zafar, Hajra; Zhu, Ying; Ren, Yuan; -Ullah, Aftab; Khan, Asif Ullah; He, Xinyi; Han, Han; Aquib, Md; Boakye-Yiadom, Kofi Oti; Ge, Liang

    2018-01-18

    Hydrogels evolved as an outstanding carrier material for local and controlled drug delivery that tend to overcome the shortcomings of old conventional dosage forms for small drugs (NSAIDS) and large peptides and proteins. The aqueous swellable and crosslinked polymeric network structure of hydrogels is composed of various natural, synthetic and semisynthetic biodegradable polymers. Hydrogels have remarkable properties of functionality, reversibility, sterilizability, and biocompatibility. All these dynamic properties of hydrogels have increased the interest in their use as a carrier for peptides and proteins to be released slowly in a sustained manner. Peptide and proteins are remarkable therapeutic agents in today's world that allow the treatment of severe, chronic and life-threatening diseases, such as diabetes, rheumatoid arthritis, hepatitis. Despite few limitations, hydrogels provide fine tuning of proteins and peptides delivery with enormous impact in clinical medicine. Novels drug delivery systems composed of smart peptides and molecules have the ability to drive self-assembly and form hydrogels at physiological pH. These hydrogels are significantly important for biological and medical fields. The primary objective of this article is to review current issues concerned with the therapeutic peptides and proteins and impact of remarkable properties of hydrogels on these therapeutic agents. Different routes for pharmaceutical peptides and proteins and superiority over other drugs candidates are presented. Recent advances based on various approaches like self-assembly of peptides and small molecules to form novel hydrogels are also discussed. The article will also review the literature concerning the classification of hydrogels on a different basis, polymers used, "release mechanisms" their physical and chemical characteristics and diverse applications.

  2. Aquatic toxicity and biodegradability of advanced cationic surfactant APA-22 compatible with the aquatic environment.

    Science.gov (United States)

    Yamane, Masayuki; Toyo, Takamasa; Inoue, Katsuhisa; Sakai, Takaya; Kaneko, Youhei; Nishiyama, Naohiro

    2008-01-01

    Cationic surfactant is a chemical substance used in hair conditioner, fabric softener and other household products. By investigating the relationship between the aquatic toxicity and the chemical structures of two types of mono alkyl cationic surfactants, alkyl trimethylammonium salts and alkyl dimethylamine salts, we have found that the C22 alkyl chain length is effective to reduce the toxicity. Besides, we have recognized that the amidopropyl functional group contributes to the enhanced biodegradability by investigating the biodegradation trend of (alkylamidopropyl)dimethylamine salt (alkyl chain length: C18). Based on these findings, we have developed mono alkyl cationic surfactant called APA-22, N-[3-(dimethylamino)propyl]docosanamide salt. APA-22 is formed by the C22 alkyl chain, amidopropyl functional group and di-methyltertiary amine group. We evaluated the aerobic and anaerobic biodegradability of APA-22 by two standard methods (OECD Test Guideline 301B and ECETOC technical document No.28) and found that this substance was degraded rapidly in both conditions. The toxicity to algae, invertebrate and fish of this substance are evaluated by using OECD Test Guideline 201, 202 and 203, respectively. All acute toxicity values are >1 mg/L, which indicates that environmental toxicity of this substance is relatively less toxic to aquatic organism. In addition, we estimated the biodegradation pathway of APA-22 and observed the complete disappearance of APA-22 and its intermediates during the test periods. Based on the environmental data provided above, we concluded that APA22 is more compatible with the aquatic environment compared to other cationic surfactants with mono long alkyl chain.

  3. Advanced bredigite-containing magnesium-matrix composites for biodegradable bone implant applications.

    Science.gov (United States)

    Dezfuli, Sina Naddaf; Huan, Zhiguang; Mol, Arjan; Leeflang, Sander; Chang, Jiang; Zhou, Jie

    2017-10-01

    The present research was aimed at developing magnesium-matrix composites that could allow effective control over their physiochemical and mechanical responses when in contact with physiological solutions. A biodegradable, bioactive ceramic - bredigite was chosen as the reinforcing phase in the composites, based on the hypothesis that the silicon- and magnesium-containing ceramic could protect magnesium from fast corrosion and at the same time stimulate cell proliferation. Methods to prepare composites with integrated microstructures - a prerequisite to achieve controlled biodegradation were developed. A systematic experimental approach was taken in order to elucidate the in vitro biodegradation mechanisms and kinetics of the composites. It was found that the composites with 20-40% homogenously dispersed bredigite particles, prepared from powders, could indeed significantly decrease the degradation rate of magnesium by up to 24 times. Slow degradation of the composites resulted in the retention of the mechanical integrity of the composites within the strength range of cortical bone after 12days of immersion in a cell culture medium. Cell attachment, cytotoxicity and bioactivity tests confirmed the stimulatory effects of bredigite embedded in the composites on the attachment, viability and differentiation of bone marrow stromal cells. Thus, the multiple benefits of adding bredigite to magnesium in enhancing degradation behavior, mechanical properties, biocompatibility and bioactivity were obtained. The results from this research showed the excellent potential of the bredigite-containing composites for bone implant applications, thus warranting further in vitro and in vivo research. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Current advances in hepatic SPECT imaging

    International Nuclear Information System (INIS)

    Van Heertum, R.L.

    1986-01-01

    Greater accuracy of SPECT imaging is primarily related to improved image contrast and better spatial resolution at increasing distances from the surface of the detector. The SPECT techniques appear to be most accurate in evaluation of liver disease when displayed and interpreted in at least three planes. This approach is particularly important in the evaluation of presence and extent of disease, as well as in the differentiation of intra-versus extra-hepatic disease. SPECT imaging of the liver compares quite well with transmission CAT scanning. The SPECT technique is superior to CAT in the evaluation of diffuse liver disease and is useful for the assessment of both superficial defects and deeper defects throughout the liver. CAT scanning is more useful for the assessment of the porta hepatis and for the evaluation of focal liver disease. The current approach is to recommend the SPECT examination as the first procedure for evaluation of focal and diffuse space-occupying liver disease. Those cases in need of additional diagnostic information are then referred for a CAT scan

  5. Advanced radiation chemistry research: Current status

    International Nuclear Information System (INIS)

    1995-10-01

    Radiation chemistry is a branch of chemistry that studies chemical transformations in materials exposed to high-energy radiations. It is based on the use of ionizing radiation as the initiator or catalyst in chemical reactions. The most significant advantage of radiation chemistry lies in its ability to be used in the production and study of almost any reactive atomic and molecular species playing a part in chemical reaction, synthesis, industrial processes, or in biological systems. Over the the last few years a number of meetings have taken place, under the auspices of the IAEA, in order to evaluate recent developments in radiation chemistry as well as the trends indicated by the results obtained. Radiation chemists from different countries have participated at these meetings. The present publication, a companion to the previous publication - New Trends and Development in Radiation Chemistry, IAEA-TECDOC-527 (1989) - includes some of the important contributions presented at these meetings. It is hoped that it will provide a useful overview of current activities and of emerging trends in this field, thus promoting better understanding of potential contributions of radiation chemistry to other fields of knowledge as well as to practical applications in industry, medicine and agriculture. Refs, figs and tabs

  6. Behavioral cardiology: current advances and future directions.

    Science.gov (United States)

    Rozanski, Alan

    2014-07-08

    Growing epidemiological evidence identifies key domains relevant to behavioral cardiology, including health behaviors, emotions, mental mindsets, stress management, social connectedness, and a sense of purpose. Each of these domains exists along a continuum, ranging from positive factors that promote health, to negative factors, which are pathophysiological. To date, there has been relatively little translation of this growing knowledge base into cardiology practice. Four initiatives are proposed to meet this challenge: 1) promulgating greater awareness of the potency of psychosocial risks factors; 2) overcoming a current "artificial divide" between conventional and psychosocial risk factors; 3) developing novel cost-effective interventions using Internet and mobile health applications, group-based counseling, and development of tiered-care behavioral management; and 4) in recognition that "one size does not fit all" with respect to behavioral interventions, developing specialists who can counsel patients in multidisciplinary fashion and use evidence-based approaches for promoting patient motivation and execution of health goals. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  7. Resistance of Magnesium Alloys to Corrosion Fatigue for Biodegradable Implant Applications: Current Status and Challenges

    Science.gov (United States)

    Raman, R. K. Singh; Harandi, Shervin Eslami

    2017-01-01

    Magnesium (Mg) alloys are attracting increasing interest as the most suitable metallic materials for construction of biodegradable and bio-absorbable temporary implants. However, Mg-alloys can suffer premature and catastrophic fracture under the synergy of cyclic loading and corrosion (i.e., corrosion fatigue (CF)). Though Mg alloys are reported to be susceptible to CF also in the corrosive human body fluid, there are very limited studies on this topic. Furthermore, the in vitro test parameters employed in these investigations have not properly simulated the actual conditions in the human body. This article presents an overview of the findings of available studies on the CF of Mg alloys in pseudo-physiological solutions and the employed testing procedures, as well as identifying the knowledge gap. PMID:29144428

  8. Combination of Advanced Oxidation and/or Reductive Dehalogenation and Biodegradation for the Decontamination of Waters Contaminated with Chlorinated Organic Compounds.

    Czech Academy of Sciences Publication Activity Database

    Kaštánek, František; Maléterová, Ywetta; Kaštánek, P.

    2007-01-01

    Roč. 42, 7 (2007) , s. 1613-1625 ISSN 0149-6395 R&D Projects: GA MPO FI-IM3/050 Institutional research plan: CEZ:AV0Z40720504 Keywords : advanced oxidation * fenton reaction * consecutive aerobic biodegradation Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.048, year: 2007

  9. Environmental Impact of Ionic Liquids: Recent Advances in (Eco)toxicology and (Bio)degradability.

    Science.gov (United States)

    Costa, Susana P F; Azevedo, Ana M O; Pinto, Paula C A G; Saraiva, M Lúcia M F S

    2017-06-09

    This Review aims to integrate the most recent and pertinent data available on the (bio)degradability and toxicity of ionic liquids for global and critical analysis and on the conscious use of these compounds on a large scale thereafter. The integrated data will enable focus on the recognition of toxicophores and on the way the community has been dealing with them, with the aim to obtain greener and safer ionic liquids. Also, an update of the most recent biotic and abiotic methods developed to overcome some of these challenging issues will be presented. The review structure aims to present a potential sequence of events that can occur upon discharging ionic liquids into the environment and the potential long-term consequences. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Assessment of current quality of biodegradable municipal waste separated by residents of Kroměříž

    Directory of Open Access Journals (Sweden)

    Bohdan Stejskal

    2010-01-01

    Full Text Available In an effort to meet the requirements for maximum material utilization, which is set forth in the Act No. 185/2001 Coll. on Waste and amendments to other Acts, and to achieve the objectives of the Waste Management Plan of the Czech Republic to reduce biodegradable waste going to landfill, a proposal for widespread deployment of separate collection and processing of biodegradable municipal waste in municipalities has become part of the amendment Act prepared by the ministry. In many places of the country pilot projects have been launched to test the technology and logistics of sorting, collecting, processing and utilizing biodegradable municipal waste separated by residents.Separate collection of biodegradable municipal waste in Kroměříž was launched as a pilot project in 1992. Despite all the residents’ education, the management of Biopas is not satisfied with the quality of biodegradable waste separation; problems occur especially in the residential area. Biodegradable waste separated by residents, due to its unacceptable amount of impurities, is transported to the landfill Kuchyňky near the village Zdounky 10 km distant but detailed data on the amount of impurities in separate biodegradable municipal waste were missing.Therefore an analysis of separate biodegradable municipal waste has been carried out. Individual samples were collected within two days of separate waste delivery, without any modifications (scattering, compaction. The sample size was at least 200 kg, the sample was manually sorted according to the Catalogue of Waste into biodegradable waste (200201, other non-biodegradable waste (200203 and biodegradable waste unsuitable for composting (e.g. animal by-products. It was found that the amount of unacceptable impurities in separate biodegradable waste considerably varies from 1 to 9 %wt.It can be concluded that the amount of unacceptable impurities in biowaste is too large to allow composting and compost production (in

  11. Hot spots and dark current in advanced plasma wakefield accelerators

    Directory of Open Access Journals (Sweden)

    G. G. Manahan

    2016-01-01

    Full Text Available Dark current can spoil witness bunch beam quality and acceleration efficiency in particle beam-driven plasma wakefield accelerators. In advanced schemes, hot spots generated by the drive beam or the wakefield can release electrons from higher ionization threshold levels in the plasma media. These electrons may be trapped inside the plasma wake and will then accumulate dark current, which is generally detrimental for a clear and unspoiled plasma acceleration process. Strategies for generating clean and robust, dark current free plasma wake cavities are devised and analyzed, and crucial aspects for experimental realization of such optimized scenarios are discussed.

  12. Predictions of fast wave heating, current drive, and current drive antenna arrays for advanced tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Batchelor, D.B.; Baity, F.W.; Carter, M.D. [and others

    1994-12-31

    The objective of the advanced tokamak program is to optimize plasma performance leading to a compact tokamak reactor through active, steady state control of the current profile using non-inductive current drive and profile control. To achieve these objectives requires compatibility and flexibility in the use of available heating and current drive systems--ion cyclotron radio frequency (ICRF), neutral beams, and lower hybrid. For any advanced tokamak, the following are important challenges to effective use of fast waves in various roles of direct electron heating, minority ion heating, and current drive: (1) to employ the heating and current drive systems to give self-consistent pressure and current profiles leading to the desired advanced tokamak operating modes; (2) to minimize absorption of the fast waves by parasitic resonances, which limit current drive; (3) to optimize and control the spectrum of fast waves launched by the antenna array for the required mix of simultaneous heating and current drive. The authors have addressed these issues using theoretical and computational tools developed at a number of institutions by benchmarking the computations against available experimental data and applying them to the specific case of TPX.

  13. Predictions of fast wave heating, current drive, and current drive antenna arrays for advanced tokamaks

    International Nuclear Information System (INIS)

    Batchelor, D.B.; Baity, F.W.; Carter, M.D.

    1994-01-01

    The objective of the advanced tokamak program is to optimize plasma performance leading to a compact tokamak reactor through active, steady state control of the current profile using non-inductive current drive and profile control. To achieve these objectives requires compatibility and flexibility in the use of available heating and current drive systems--ion cyclotron radio frequency (ICRF), neutral beams, and lower hybrid. For any advanced tokamak, the following are important challenges to effective use of fast waves in various roles of direct electron heating, minority ion heating, and current drive: (1) to employ the heating and current drive systems to give self-consistent pressure and current profiles leading to the desired advanced tokamak operating modes; (2) to minimize absorption of the fast waves by parasitic resonances, which limit current drive; (3) to optimize and control the spectrum of fast waves launched by the antenna array for the required mix of simultaneous heating and current drive. The authors have addressed these issues using theoretical and computational tools developed at a number of institutions by benchmarking the computations against available experimental data and applying them to the specific case of TPX

  14. Leakage Currents and Gas Generation in Advanced Wet Tantalum Capacitors

    Science.gov (United States)

    Teverovsky, Alexander

    2015-01-01

    Currently, military grade, established reliability wet tantalum capacitors are among the most reliable parts used for space applications. This has been achieved over the years by extensive testing and improvements in design and materials. However, a rapid insertion of new types of advanced, high volumetric efficiency capacitors in space systems without proper testing and analysis of degradation mechanisms might increase risks of failures. The specifics of leakage currents in wet electrolytic capacitors is that the conduction process is associated with electrolysis of electrolyte and gas generation resulting in building up of internal gas pressure in the parts. The risk associated with excessive leakage currents and increased pressure is greater for high value advanced wet tantalum capacitors, but it has not been properly evaluated yet. In this work, in Part I, leakages currents in various types of tantalum capacitors have been analyzed in a wide range of voltages, temperatures, and time under bias. Gas generation and the level of internal pressure have been calculated in Part II for different case sizes and different hermeticity leak rates to assess maximal allowable leakage currents. Effects related to electrolyte penetration to the glass seal area have been studied and the possibility of failures analyzed in Part III. Recommendations for screening and qualification to reduce risks of failures have been suggested.

  15. Current development status of advanced pressurized water reactors (APWRs)

    International Nuclear Information System (INIS)

    Seifritz, W.; Chawla, R.

    1985-08-01

    The current development status of advanced (high converting) pressurized water reactors (APWRs) is briefly reviewed. The areas covered are: reactor physics, thermohydraulics and other technical aspects, as well as electricity generating costs and longterm reactor strategical considerations related to the APWR's role in a plutonium economy. There does not seem to be any unsurmountable technical obstacle to the realization of an APWR. However, substantial further R and D efforts are required if an APWR is to go into commercial operation by the end of the century. (author)

  16. Urogenital disease: current medical need and recent advances.

    Science.gov (United States)

    Holoboski, M

    1998-11-01

    The Medicinal Chemistry Division session on Urogenital Disease began with an overview by Dr P-O Andersson (Pharmacia and Upjohn, MI, USA) of current medical need and recent advances in the field. Dr Andersson drew attention to the limited interest that pharmaceutical companies have historically shown in the area of non-malignant diseases of the urogenital tract. Conditions such as bladder overactivity and urinary incontinence, benign prostatic hyperplasia (BPH) and erectile dysfunction have been poorly understood and have been regarded as unavoidable consequences of old age. One factor, which further compounds the problem, is that many people do not seek treatment, a practice which tends to lower the awareness of these conditions.

  17. Advanced Curation of Current and Future Extraterrestrial Samples

    Science.gov (United States)

    Allen, Carlton C.

    2013-01-01

    Curation of extraterrestrial samples is the critical interface between sample return missions and the international research community. Curation includes documentation, preservation, preparation, and distribution of samples. The current collections of extraterrestrial samples include: Lunar rocks / soils collected by the Apollo astronauts Meteorites, including samples of asteroids, the Moon, and Mars "Cosmic dust" (asteroid and comet particles) collected by high-altitude aircraft Solar wind atoms collected by the Genesis spacecraft Comet particles collected by the Stardust spacecraft Interstellar dust collected by the Stardust spacecraft Asteroid particles collected by the Hayabusa spacecraft These samples were formed in environments strikingly different from that on Earth. Terrestrial contamination can destroy much of the scientific significance of many extraterrestrial materials. In order to preserve the research value of these precious samples, contamination must be minimized, understood, and documented. In addition the samples must be preserved - as far as possible - from physical and chemical alteration. In 2011 NASA selected the OSIRIS-REx mission, designed to return samples from the primitive asteroid 1999 RQ36 (Bennu). JAXA will sample C-class asteroid 1999 JU3 with the Hayabusa-2 mission. ESA is considering the near-Earth asteroid sample return mission Marco Polo-R. The Decadal Survey listed the first lander in a Mars sample return campaign as its highest priority flagship-class mission, with sample return from the South Pole-Aitken basin and the surface of a comet among additional top priorities. The latest NASA budget proposal includes a mission to capture a 5-10 m asteroid and return it to the vicinity of the Moon as a target for future sampling. Samples, tools, containers, and contamination witness materials from any of these missions carry unique requirements for acquisition and curation. Some of these requirements represent significant advances over

  18. A Review on Recent Advances in Stabilizing Peptides/Proteins upon Fabrication in Hydrogels from Biodegradable Polymers

    OpenAIRE

    Faisal Raza; Hajra Zafar; Ying Zhu; Yuan Ren; Aftab -Ullah; Asif Ullah Khan; Xinyi He; Han Han; Md Aquib; Kofi Oti Boakye-Yiadom; Liang Ge

    2018-01-01

    Hydrogels evolved as an outstanding carrier material for local and controlled drug delivery that tend to overcome the shortcomings of old conventional dosage forms for small drugs (NSAIDS) and large peptides and proteins. The aqueous swellable and crosslinked polymeric network structure of hydrogels is composed of various natural, synthetic and semisynthetic biodegradable polymers. Hydrogels have remarkable properties of functionality, reversibility, sterilizability, and biocompatibility. All...

  19. Evaluation of advanced and current leak detection systems

    International Nuclear Information System (INIS)

    Kupperman, D.S.

    1988-01-01

    U.S. Nuclear Regulatory Commission Guide 1.45 recommends the use of at least three different detection methods in reactors to detect leakage. Monitoring of both sump-flow and airborne particulate radioactivity is mandatory. A third method can involve either monitoring of condensate flow rate from air coolers or monitoring of airborne gaseous radioactivity. Although the methods currently used for leak detection reflect the state of the art, other techniques may be developed and used. Since the recommendations of Regulatory Guide 1.45 are not mandatory, Licensee Event Report Compilations have been reviewed to help establish actual capabilities for leak detection. The review of event reports, which had previously covered the period of June 1985 to August 1986 has been extended, and now covers events to June 1987. The total number of significant events is now 83. These reports have provided documented, sometimes detailed, summaries of reactor leaks. They have helped establish the capabilities of existing systems to detect and locate leaks. Differences between PWRs and BWRs with regard to leak detection have now been analyzed. With regard to detection methods, the greatest differences between reactor types are as follows: (a) The sump pump is reported as the detection method more frequently in BWRs than in PWRs (64% vs. 35%). (b) The radiation monitor is reported as the detection method (excluding false alarms) more frequently in PWRs. Current efforts at Argonne National Laboratory (ANL) to evaluate advanced acoustic leak detection methods are directed toward the generation and analysis of acoustic data from large (0.5 to 10 gal/min) leaks and modification of the software of the GARD/ANL advanced acoustic leak detection system. In order to reach the goal of 10 gal/min leaks, the Steam Generator Test Facility at ANL has been modified to carry out the leak testing. Tests were carried out with water at 525 deg. F and 1100 psi leaking through a fatigue crack in a 4-in

  20. Drugs in development for toxoplasmosis: advances, challenges, and current status

    Directory of Open Access Journals (Sweden)

    Alday PH

    2017-01-01

    Full Text Available P Holland Alday,1 Joseph Stone Doggett1,2 1Division of Infectious Diseases, Oregon Health & Science University, 2Portland Veterans Affairs Medical Center, Portland, OR, USA Abstract: Toxoplasma gondii causes fatal and debilitating brain and eye diseases. Medicines that are currently used to treat toxoplasmosis commonly have toxic side effects and require prolonged courses that range from weeks to more than a year. The need for long treatment durations and the risk of relapsing disease are in part due to the lack of efficacy against T. gondii tissue cysts. The challenges for developing a more effective treatment for toxoplasmosis include decreasing toxicity, achieving therapeutic concentrations in the brain and eye, shortening duration, eliminating tissue cysts from the host, safety in pregnancy, and creating a formulation that is inexpensive and practical for use in resource-poor areas of the world. Over the last decade, significant progress has been made in identifying and developing new compounds for the treatment of toxoplasmosis. Unlike clinically used medicines that were repurposed for toxoplasmosis, these compounds have been optimized for efficacy against toxoplasmosis during preclinical development. Medicines with enhanced efficacy as well as features that address the unique aspects of toxoplasmosis have the potential to greatly improve toxoplasmosis therapy. This review discusses the facets of toxoplasmosis that are pertinent to drug design and the advances, challenges, and current status of preclinical drug research for toxoplasmosis. Keywords: Toxoplasma gondii, therapeutics, preclinical medicine, experimental medicine, mechanism of action, Apicomplexa

  1. Drugs in development for toxoplasmosis: advances, challenges, and current status.

    Science.gov (United States)

    Alday, P Holland; Doggett, Joseph Stone

    2017-01-01

    Toxoplasma gondii causes fatal and debilitating brain and eye diseases. Medicines that are currently used to treat toxoplasmosis commonly have toxic side effects and require prolonged courses that range from weeks to more than a year. The need for long treatment durations and the risk of relapsing disease are in part due to the lack of efficacy against T. gondii tissue cysts. The challenges for developing a more effective treatment for toxoplasmosis include decreasing toxicity, achieving therapeutic concentrations in the brain and eye, shortening duration, eliminating tissue cysts from the host, safety in pregnancy, and creating a formulation that is inexpensive and practical for use in resource-poor areas of the world. Over the last decade, significant progress has been made in identifying and developing new compounds for the treatment of toxoplasmosis. Unlike clinically used medicines that were repurposed for toxoplasmosis, these compounds have been optimized for efficacy against toxoplasmosis during preclinical development. Medicines with enhanced efficacy as well as features that address the unique aspects of toxoplasmosis have the potential to greatly improve toxoplasmosis therapy. This review discusses the facets of toxoplasmosis that are pertinent to drug design and the advances, challenges, and current status of preclinical drug research for toxoplasmosis.

  2. Current Knowledge and Recent Advances in Marine Dinoflagellate Transcriptomic Research

    Directory of Open Access Journals (Sweden)

    Muhamad Afiq Akbar

    2018-02-01

    Full Text Available Dinoflagellates are essential components in marine ecosystems, and they possess two dissimilar flagella to facilitate movement. Dinoflagellates are major components of marine food webs and of extreme importance in balancing the ecosystem energy flux in oceans. They have been reported to be the primary cause of harmful algae bloom (HABs events around the world, causing seafood poisoning and therefore having a direct impact on human health. Interestingly, dinoflagellates in the genus Symbiodinium are major components of coral reef foundations. Knowledge regarding their genes and genome organization is currently limited due to their large genome size and other genetic and cytological characteristics that hinder whole genome sequencing of dinoflagellates. Transcriptomic approaches and genetic analyses have been employed to unravel the physiological and metabolic characteristics of dinoflagellates and their complexity. In this review, we summarize the current knowledge and findings from transcriptomic studies to understand the cell growth, effects on environmental stress, toxin biosynthesis, dynamic of HABs, phylogeny and endosymbiosis of dinoflagellates. With the advancement of high throughput sequencing technologies and lower cost of sequencing, transcriptomic approaches will likely deepen our understanding in other aspects of dinoflagellates’ molecular biology such as gene functional analysis, systems biology and development of model organisms.

  3. Biodegradable Polymers

    OpenAIRE

    Vroman, Isabelle; Tighzert, Lan

    2009-01-01

    Biodegradable materials are used in packaging, agriculture, medicine and other areas. In recent years there has been an increase in interest in biodegradable polymers. Two classes of biodegradable polymers can be distinguished: synthetic or natural polymers. There are polymers produced from feedstocks derived either from petroleum resources (non renewable resources) or from biological resources (renewable resources). In general natural polymers offer fewer advantages than synthetic polymers. ...

  4. Advanced Curation: Solving Current and Future Sample Return Problems

    Science.gov (United States)

    Fries, M.; Calaway, M.; Evans, C.; McCubbin, F.

    2015-01-01

    Advanced Curation is a wide-ranging and comprehensive research and development effort at NASA Johnson Space Center that identifies and remediates sample related issues. For current collections, Advanced Curation investigates new cleaning, verification, and analytical techniques to assess their suitability for improving curation processes. Specific needs are also assessed for future sample return missions. For each need, a written plan is drawn up to achieve the requirement. The plan draws while upon current Curation practices, input from Curators, the analytical expertise of the Astromaterials Research and Exploration Science (ARES) team, and suitable standards maintained by ISO, IEST, NIST and other institutions. Additionally, new technologies are adopted on the bases of need and availability. Implementation plans are tested using customized trial programs with statistically robust courses of measurement, and are iterated if necessary until an implementable protocol is established. Upcoming and potential NASA missions such as OSIRIS-REx, the Asteroid Retrieval Mission (ARM), sample return missions in the New Frontiers program, and Mars sample return (MSR) all feature new difficulties and specialized sample handling requirements. The Mars 2020 mission in particular poses a suite of challenges since the mission will cache martian samples for possible return to Earth. In anticipation of future MSR, the following problems are among those under investigation: What is the most efficient means to achieve the less than 1.0 ng/sq cm total organic carbon (TOC) cleanliness required for all sample handling hardware? How do we maintain and verify cleanliness at this level? The Mars 2020 Organic Contamination Panel (OCP) predicts that organic carbon, if present, will be present at the "one to tens" of ppb level in martian near-surface samples. The same samples will likely contain wt% perchlorate salts, or approximately 1,000,000x as much perchlorate oxidizer as organic carbon

  5. The payloads of Advanced Virgo: current status and upgrades

    Science.gov (United States)

    Naticchioni, L.; Virgo Collaboration

    2018-02-01

    The development and integration of new detector payloads has been an important part of the Advanced Virgo (AdV) project, the major upgrade of the Virgo interferometric detector of Gravitational Waves, aiming to increase the detector sensitivity by one order of magnitude. During the integration phase of the new AdV payloads with monolithic suspension of mirrors we experienced systematic suspension failures later identified as caused by dust contamination of the vacuum system. In order to not postpone the detector commissioning, making possible to join the LIGO O2 observation run, the Collaboration decided to proceed with the integration of the payloads relying on steel wire suspensions for all the mirrors. In this proceeding the status of the currently integrated payloads is reported, including their angular control characterization and the Q-factor measurements for test mass steel wire suspensions. The payload upgrade for the re-integration of monolithic suspensions after the O2 run is reported in the last section.

  6. Breast cancer stem cells: current advances and clinical implications.

    Science.gov (United States)

    Luo, Ming; Clouthier, Shawn G; Deol, Yadwinder; Liu, Suling; Nagrath, Sunitha; Azizi, Ebrahim; Wicha, Max S

    2015-01-01

    There is substantial evidence that many cancers, including breast cancer, are driven by a population of cells that display stem cell properties. These cells, termed cancer stem cells (CSCs) or tumor initiating cells, not only drive tumor initiation and growth but also mediate tumor metastasis and therapeutic resistance. In this chapter, we summarize current advances in CSC research with a major focus on breast CSCs (BCSCs). We review the prevailing methods to isolate and characterize BCSCs and recent evidence documenting their cellular origins and phenotypic plasticity that enables them to transition between mesenchymal and epithelial-like states. We describe in vitro and clinical evidence that these cells mediate metastasis and treatment resistance in breast cancer, the development of novel strategies to isolate circulating tumor cells (CTCs) that contain CSCs and the use of patient-derived xenograft (PDX) models in preclinical breast cancer research. Lastly, we highlight several signaling pathways that regulate BCSC self-renewal and describe clinical implications of targeting these cells for breast cancer treatment. The development of strategies to effectively target BCSCs has the potential to significantly improve the outcomes for patients with breast cancer.

  7. Current advances in precious metal core–shell catalyst design

    Science.gov (United States)

    Wang, Xiaohong; He, Beibei; Hu, Zhiyu; Zeng, Zhigang; Han, Sheng

    2014-01-01

    Precious metal nanoparticles are commonly used as the main active components of various catalysts. Given their high cost, limited quantity, and easy loss of catalytic activity under severe conditions, precious metals should be used in catalysts at low volumes and be protected from damaging environments. Accordingly, reducing the amount of precious metals without compromising their catalytic performance is difficult, particularly under challenging conditions. As multifunctional materials, core–shell nanoparticles are highly important owing to their wide range of applications in chemistry, physics, biology, and environmental areas. Compared with their single-component counterparts and other composites, core–shell nanoparticles offer a new active interface and a potential synergistic effect between the core and shell, making these materials highly attractive in catalytic application. On one hand, when a precious metal is used as the shell material, the catalytic activity can be greatly improved because of the increased surface area and the closed interfacial interaction between the core and the shell. On the other hand, when a precious metal is applied as the core material, the catalytic stability can be remarkably improved because of the protection conferred by the shell material. Therefore, a reasonable design of the core–shell catalyst for target applications must be developed. We summarize the latest advances in the fabrications, properties, and applications of core–shell nanoparticles in this paper. The current research trends of these core–shell catalysts are also highlighted. PMID:27877695

  8. Recovery of resources for advanced life support space applications: effect of retention time on biodegradation of two crop residues in a fed-batch, continuous stirred tank reactor

    Science.gov (United States)

    Strayer, R. F.; Finger, B. W.; Alazraki, M. P.; Cook, K.; Garland, J. L.

    2002-01-01

    Bioreactor retention time is a key process variable that will influence costs that are relevant to long distance space travel or long duration space habitation. However. little is known about the effects of this parameter on the microbiological treatment options that are being proposed for Advanced Life Support (ALS) systems. Two bioreactor studies were designed to examine this variable. In the first one, six retention times ranging from 1.3 to 21.3 days--were run in duplicate, 81 working-volume continuous stirred tank reactors (CSTR) that were fed ALS wheat residues. Ash-free dry weight loss, carbon mineralization, soluble TOC reduction, changes in fiber content (cellulose, hemicellulose, and lignin), bacterial numbers, and mineral recoveries were monitored. At short retention times--1.33 days--biodegradation was poor (total: 16-20%, cellulose - 12%, hemicellulose - 28%) but soluble TOC was decreased by 75-80% and recovery of major crop inorganic nutrients was adequate, except for phosphorus. A high proportion of the total bacteria (ca. 83%) was actively respiring. At the longest retention time tested, 21.3 days, biodegradation was good (total: 55-60%, cellulose ca. 70%, hemicellulose - ca. 55%) and soluble TOC was decreased by 80%. Recovery of major nutrients, except phosphorus, remained adequate. A very low proportion of total bacteria was actively respiring (ca. 16%). The second bioreactor study used potato residue to determine if even shorter retention times could be used (range 0.25-2.0 days). Although overall biodegradation deteriorated, the degradation of soluble TOC continued to be ca. 75%. We conclude that if the goal of ALS bioprocessing is maximal degradation of crop residues, including cellulose, then retention times of 10 days or longer will be needed. If the goal is to provide inorganic nutrients with the smallest volume/weight bioreactor possible, then a retention time of 1 day (or less) is sufficient.

  9. Current Advances in Detection and Treatment of Babesiosis

    Science.gov (United States)

    Mosqueda, J; Olvera-Ramírez, A; Aguilar-Tipacamú, G; Cantó, GJ

    2012-01-01

    Babesiosis is a disease with a world-wide distribution affecting many species of mammals principally cattle and man. The major impact occurs in the cattle industry where bovine babesiosis has had a huge economic effect due to loss of meat and beef production of infected animals and death. Nowadays to those costs there must be added the high cost of tick control, disease detection, prevention and treatment. In almost a century and a quarter since the first report of the disease, the truth is: there is no a safe and efficient vaccine available, there are limited chemotherapeutic choices and few low-cost, reliable and fast detection methods. Detection and treatment of babesiosis are important tools to control babesiosis. Microscopy detection methods are still the cheapest and fastest methods used to identify Babesia parasites although their sensitivity and specificity are limited. Newer immunological methods are being developed and they offer faster, more sensitive and more specific options to conventional methods, although the direct immunological diagnoses of parasite antigens in host tissues are still missing. Detection methods based on nucleic acid identification and their amplification are the most sensitive and reliable techniques available today; importantly, most of those methodologies were developed before the genomics and bioinformatics era, which leaves ample room for optimization. For years, babesiosis treatment has been based on the use of very few drugs like imidocarb or diminazene aceturate. Recently, several pharmacological compounds were developed and evaluated, offering new options to control the disease. With the complete sequence of the Babesia bovis genome and the B. bigemina genome project in progress, the post-genomic era brings a new light on the development of diagnosis methods and new chemotherapy targets. In this review, we will present the current advances in detection and treatment of babesiosis in cattle and other animals, with additional

  10. Editorial: Biodegradable Materials

    Directory of Open Access Journals (Sweden)

    Carl Schaschke

    2014-11-01

    Full Text Available This Special Issue “Biodegradable Materials” features research and review papers concerning recent advances on the development, synthesis, testing and characterisation of biomaterials. These biomaterials, derived from natural and renewable sources, offer a potential alternative to existing non-biodegradable materials with application to the food and biomedical industries amongst many others. In this Special Issue, the work is expanded to include the combined use of fillers that can enhance the properties of biomaterials prepared as films. The future application of these biomaterials could have an impact not only at the economic level, but also for the improvement of the environment.

  11. Advanced robotics for medical rehabilitation current state of the art and recent advances

    CERN Document Server

    Xie, Shane

    2016-01-01

    Focussing on the key technologies in developing robots for a wide range of medical rehabilitation activities – which will include robotics basics, modelling and control, biomechanics modelling, rehabilitation strategies, robot assistance, clinical setup/implementation as well as neural and muscular interfaces for rehabilitation robot control – this book is split into two parts; a review of the current state of the art, and recent advances in robotics for medical rehabilitation. Both parts will include five sections for the five key areas in rehabilitation robotics: (i) the upper limb; (ii) lower limb for gait rehabilitation (iii) hand, finger and wrist; (iv) ankle for strains and sprains; and (v) the use of EEG and EMG to create interfaces between the neurological and muscular functions of the patients and the rehabilitation robots. Each chapter provides a description of the design of the device, the control system used, and the implementation and testing to show how it fulfils the needs of that specific ...

  12. Technological advances in perioperative monitoring: Current concepts and clinical perspectives.

    Science.gov (United States)

    Chilkoti, Geetanjali; Wadhwa, Rachna; Saxena, Ashok Kumar

    2015-01-01

    Minimal mandatory monitoring in the perioperative period recommended by Association of Anesthetists of Great Britain and Ireland and American Society of Anesthesiologists are universally acknowledged and has become an integral part of the anesthesia practice. The technologies in perioperative monitoring have advanced, and the availability and clinical applications have multiplied exponentially. Newer monitoring techniques include depth of anesthesia monitoring, goal-directed fluid therapy, transesophageal echocardiography, advanced neurological monitoring, improved alarm system and technological advancement in objective pain assessment. Various factors that need to be considered with the use of improved monitoring techniques are their validation data, patient outcome, safety profile, cost-effectiveness, awareness of the possible adverse events, knowledge of technical principle and ability of the convenient routine handling. In this review, we will discuss the new monitoring techniques in anesthesia, their advantages, deficiencies, limitations, their comparison to the conventional methods and their effect on patient outcome, if any.

  13. Current status and prospect of therapy with advanced cancer

    International Nuclear Information System (INIS)

    Watari, Tsutomu

    1979-01-01

    Symtomatic or palliative therapy of the patients with advanced cancer must be directed to the relief of specific distressing symptoms caused by or associated with neoplasm. The radiotherapy must have a clear concepts of the potential accomplishments of other treatment modalities, such as neurosurgery, anesthesiology, chemotherapy, pharmacology and psychotherapy, so that he may use his own method in proper perspective. I discussed following is an list of contents in this papers. Relief of pain, Psychotherapy, SVC obstruction, Obstructive jaundice, Brain and lung metastasis, prevention of fracture, Skin metastasis, Liver metastasis and treatment of advanced pediaric tumor etc. For the future: 1) Establishment of Stage and Grade of advanced cancer. 2) Development of new chemotherapeutic drug and immunotherapy. 3) Combination of multidisciplinary team and multidisciplinary treatment. (author)

  14. Recent Advances and Current Trends in Metamaterial-by-Design

    Science.gov (United States)

    Anselmi, N.; Gottardi, G.

    2018-02-01

    Thanks to their potential applications in several engineering areas, metamaterials gained much of attentions among different research communities, leading to the development of several analysis and synthesis tools. In this context, the metamaterial-by-design (MbD) paradigm has been recently introduced as a powerful tool for the design of complex metamaterials-based structures. In this work a review of the state-of-art, as well as the recent advancements of MbD-based methods are presented.

  15. Cancer and Radiation Therapy: Current Advances and Future Directions

    Science.gov (United States)

    Baskar, Rajamanickam; Lee, Kuo Ann; Yeo, Richard; Yeoh, Kheng-Wei

    2012-01-01

    In recent years remarkable progress has been made towards the understanding of proposed hallmarks of cancer development and treatment. However with its increasing incidence, the clinical management of cancer continues to be a challenge for the 21st century. Treatment modalities comprise of radiation therapy, surgery, chemotherapy, immunotherapy and hormonal therapy. Radiation therapy remains an important component of cancer treatment with approximately 50% of all cancer patients receiving radiation therapy during their course of illness; it contributes towards 40% of curative treatment for cancer. The main goal of radiation therapy is to deprive cancer cells of their multiplication (cell division) potential. Celebrating a century of advances since Marie Curie won her second Nobel Prize for her research into radium, 2011 has been designated the Year of Radiation therapy in the UK. Over the last 100 years, ongoing advances in the techniques of radiation treatment and progress made in understanding the biology of cancer cell responses to radiation will endeavor to increase the survival and reduce treatment side effects for cancer patients. In this review, principles, application and advances in radiation therapy with their biological end points are discussed. PMID:22408567

  16. Advanced fuel technology and performance: Current status and trends

    International Nuclear Information System (INIS)

    1990-11-01

    During the last years the Nuclear Fuel Cycle and Waste Management Division of the IAEA has been giving great attention to the collection, analysis and exchange of information in the field of reactor fuel technology. Most of these activities are being conducted in the framework of the International Working Group on Water Reactor Fuel Performance and Technology (IWGFPT). The purpose of this Advisory Group Meeting on Advanced Fuel Technology and Performance was to update and to continue the previous work, and to review the experience of advanced fuel technology, its performance with regard to all types of reactors and to outline the future trends on the basis of national experience and discussions during the meeting. As a result of the meeting a Summary Report was prepared which reflected the status of the advanced nuclear fuel technology up to 1990. The 10 papers presented by participants of this meeting are also published here. A separate abstract was prepared for each of these papers. Refs, figs and tabs

  17. Advanced induction motor drive control with single current sensor

    Directory of Open Access Journals (Sweden)

    Adžić Evgenije M.

    2016-01-01

    Full Text Available This paper proposes induction motor drive control method which uses minimal number of sensors, providing only DC-link current as a feedback signal. Improved DC-link current sampling scheme and modified asymmetrical switching pattern cancels characteristic waveform errors which exist in all three reconstructed motor line-currents. Motor linecurrent harmonic content is reduced to an acceptable level, eliminating torque and speed oscillations which were inherent for conventional single sensor drives. Consequently, use of single current sensor and line-current reconstruction technique is no longer acceptable only for low and medium performance drives, but also for drives where priority is obtaining a highly accurate, stable and fast response. Proposed control algorithm is validated using induction motor drive hardware prototype based on TMS320F2812 digital signal processor. [Projekat Ministarstva nauke Republike Srbije, br. III 042004 and by the Provincial Secretariat for Science and Technological Development of AP Vojvodina under contract No. 114-451-3508/2013-04

  18. A model for simultaneous crystallisation and biodegradation of biodegradable polymers.

    Science.gov (United States)

    Han, Xiaoxiao; Pan, Jingzhe

    2009-01-01

    This paper completes the model of biodegradation for biodegradable polymers that was previously developed by Wang et al. (Wang Y, Pan J, Han X, Sinka, Ding L. A phenomenological model for the degradation of biodegradable polymers. Biomaterials 2008;29:3393-401). Crystallisation during biodegradation was not considered in the previous work which is the topic of the current paper. For many commonly used biodegradable polymers, there is a strong interplay between crystallisation and hydrolysis reaction during biodegradation - the chain cleavage caused by the hydrolysis reaction provides an extra mobility for the polymer chains to crystallise and the resulting crystalline phase becomes more resistant to further hydrolysis reaction. This paper presents a complete theory to describe this interplay. The fundamental equations in the Avrami's theory for crystallisation are modified and coupled to the diffusion-reaction equations that were developed in our previous work. The mathematical equations are then applied to three biodegradable polymers for which long term degradation data are available in the literature. It is shown that the model can capture the behavior of the major biodegradable polymers very well.

  19. Absorbable and biodegradable polymers

    CERN Document Server

    Shalaby, Shalaby W

    2003-01-01

    INTRODUCTION NOTES: Absorbable/Biodegradable Polymers: Technology Evolution. DEVELOPMENT AND APPLICATIONOF NEW SYSTEMS: Segmented Copolyesters with Prolonged Strength Retention Profiles. Polyaxial Crystalline Fiber-Forming Copolyester. Polyethylene Glycol-Based Copolyesters. Cyanoacrylate-Based Systems as Tissue Adhesives. Chitosan-Based Systems. Hyaluronic Acid-Based Systems. DEVELOPMENTS IN PREPARATIVE, PROCESSING, AND EVALUATION METHODS: New Approaches to the Synthesis of Crystalline. Fiber-Forming Aliphatic Copolyesters. Advances in Morphological Development to Tailor the Performance of Me

  20. Current implementation of advance encryption standard (AES) S-Box

    African Journals Online (AJOL)

    Although the attack on cryptosystem is still not severe, the development of the scheme is still ongoing especially for the design of S-Box. Two main approach has beenused, which are heuristic method and algebraic method. Algebraic method as in current AES implementation has been proven to be the most secure S-Box ...

  1. Current advances in T-cell-based cancer immunotherapy

    Science.gov (United States)

    Wang, Mingjun; Yin, Bingnan; Wang, Helen Y; Wang, Rong-Fu

    2015-01-01

    Cancer is a leading cause of death worldwide; due to the lack of ideal cancer biomarkers for early detection or diagnosis, most patients present with late-stage disease at the time of diagnosis, thus limiting the potential for successful treatment. Traditional cancer treatments, including surgery, chemotherapy and radiation therapy, have demonstrated very limited efficacy for patients with late-stage disease. Therefore, innovative and effective cancer treatments are urgently needed for cancer patients with late-stage and refractory disease. Cancer immunotherapy, particularly adoptive cell transfer, has shown great promise in the treatment of patients with late-stage disease, including those who are refractory to standard therapies. In this review, we will highlight recent advances and discuss future directions in adoptive cell transfer based cancer immunotherapy. PMID:25524383

  2. Advances in NDT and Materials Characterization by Eddy Currents

    OpenAIRE

    Almeida, G.; Gonzalez, J.; Rosado, L.; Vilaça, P.; Santos, Telmo G.

    2013-01-01

    VK: T20309 New materials and production technologies demand improved non-destructive techniques for inspection and defect evaluation, especially when critical safety applications are involved. In this paper a new non-destructive testing (NDT) system is presented. The innovative system is composed by a new type of eddy currents probe, electronic devices for signal generation, conditioning and conversion, automated mechanized scanning and analysis software. This new probe provides enhanced l...

  3. Synergic Adsorption–Biodegradation by an Advanced Carrier for Enhanced Removal of High-Strength Nitrogen and Refractory Organics

    KAUST Repository

    Ahmad, Muhammad

    2017-03-29

    Coking wastewater contains not only high-strength nitrogen but also toxic biorefractory organics. This study presents simultaneous removal of high-strength quinoline, carbon, and ammonium in coking wastewater by immobilized bacterial communities composed of a heterotrophic strain Pseudomonas sp. QG6 (hereafter referred as QG6), ammonia-oxidizing bacteria (AOB), and anaerobic ammonium oxidation bacteria (anammox). The bacterial immobilization was implemented with the help of a self-designed porous cubic carrier that created structured microenvironments including an inner layer adapted for anaerobic bacteria, a middle layer suitable for coaggregation of certain aerobic and anaerobic bacteria, and an outer layer for heterotrophic bacteria. By coating functional polyurethane foam (FPUF) with iron oxide nanoparticles (IONPs), the biocarrier (IONPs-FPUF) could provide a good outer-layer barrier for absorption and selective treatment of aromatic compounds by QG6, offer a conducive environment for anammox in the inner layer, and provide a mutualistic environment for AOB in the middle layer. Consequently, simultaneous nitrification and denitrification were reached with the significant removal of up to 322 mg L (98%) NH, 311 mg L (99%) NO, and 633 mg L (97%) total nitrogen (8 mg L averaged NO concentration was recorded in the effluent), accompanied by an efficient removal of chemical oxygen demand by 3286 mg L (98%) and 350 mg L (100%) quinoline. This study provides an alternative way to promote synergic adsorption and biodegradation with the help of a modified biocarrier that has great potential for treatment of wastewater containing high-strength carbon, toxic organic pollutants, and nitrogen.

  4. Current breast imaging modalities, advances, and impact on breast care.

    Science.gov (United States)

    Garcia, Evelyn M; Storm, Erik S; Atkinson, Lisa; Kenny, Eileen; Mitchell, Lisa S

    2013-09-01

    Mammography will continue as the breast cancer screening imaging study of choice for the foreseeable future. Ultrasound and magnetic resonance imaging (MRI) are widely available adjunctive studies for women with suspicious mammographic or clinical findings, and MRI is a screening tool for women with specific increased risks for breast cancer. Options for diagnosis will continue to evolve and progress. This article discusses a wide variety of imaging options currently used and in development, their strengths, limitations, and potential future roles in the continuing pursuit of early breast cancer diagnosis, treatment, and follow-up. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Advanced ultrasonic and eddy current examinations of the reactor vessel

    International Nuclear Information System (INIS)

    Cvitanovic, M.; Zado, V.

    1996-01-01

    In order to improve safety and reliability of nuclear power plant components, the existing examination methods are permanently developed as well as the new methods of examination are implemented. For the same reason, beside referent requirements, complementary NDE methods are utilized. Some examination methods techniques are not required to be used by referent safety codes and standards but they are frequently practiced as additional prevention to the component failure. This article presents the state of the art methods and techniques currently applied for examination of the reactor vessel base material, clad and weld materials. (author)

  6. Pathophysiology of recent advances in current thyroid function testing

    International Nuclear Information System (INIS)

    Hesch, R.D.

    1977-01-01

    In the first chapter I have discussed thyroid function and thyroid status which is determined by thyroid gland function in secreting T4 and peripheral biotransformation of T4. The accuracy of a current in-vitro diagnostic strategy allows high reliability in clinical routine. More recent test procedures for iodothyronines and immunological phenomena need further evaluation. In another chapter the biotransformation of T4 to bioactive and regulatory iodothyronines with respect to possible clinical implications is discussed. Finally, the role of TBG for interpration of T4 and T3 concentrations is determined and more attention directed to its functional heterogeneity. (orig.) [de

  7. Oil biodegradation

    NARCIS (Netherlands)

    Rahsepar, Shokouhalsadat; Langenhoff, Alette A.M.; Smit, Martijn P.J.; Eenennaam, van Justine S.; Murk, Tinka; Rijnaarts, Huub H.M.

    2017-01-01

    During the Deepwater Horizon (DwH) oil spill, interactions between oil, clay particles and marine snow lead to the formation of aggregates. Interactions between these components play an important, but yet not well understood, role in biodegradation of oil in the ocean water. The aim of this study

  8. Current advancements and challenges in soil-root interactions modelling

    Science.gov (United States)

    Schnepf, Andrea; Huber, Katrin; Abesha, Betiglu; Meunier, Felicien; Leitner, Daniel; Roose, Tiina; Javaux, Mathieu; Vanderborght, Jan; Vereecken, Harry

    2015-04-01

    Roots change their surrounding soil chemically, physically and biologically. This includes changes in soil moisture and solute concentration, the exudation of organic substances into the rhizosphere, increased growth of soil microorganisms, or changes in soil structure. The fate of water and solutes in the root zone is highly determined by these root-soil interactions. Mathematical models of soil-root systems in combination with non-invasive techniques able to characterize root systems are a promising tool to understand and predict the behaviour of water and solutes in the root zone. With respect to different fields of applications, predictive mathematical models can contribute to the solution of optimal control problems in plant recourse efficiency. This may result in significant gains in productivity, efficiency and environmental sustainability in various land use activities. Major challenges include the coupling of model parameters of the relevant processes with the surrounding environment such as temperature, nutrient concentration or soil water content. A further challenge is the mathematical description of the different spatial and temporal scales involved. This includes in particular the branched structures formed by root systems or the external mycelium of mycorrhizal fungi. Here, reducing complexity as well as bridging between spatial scales is required. Furthermore, the combination of experimental and mathematical techniques may advance the field enormously. Here, the use of root system, soil and rhizosphere models is presented through a number of modelling case studies, including image based modelling of phosphate uptake by a root with hairs, model-based optimization of root architecture for phosphate uptake from soil, upscaling of rhizosphere models, modelling root growth in structured soil, and the effect of root hydraulic architecture on plant water uptake efficiency and drought resistance.

  9. Current advances in transdermal delivery of drugs for Alzheimer's disease.

    Science.gov (United States)

    Nguyen, Thuy Trang; Giau, Vo Van; Vo, Tuong Kha

    2017-01-01

    Alzheimer's disease (AD) is a common, progressive, fatal neurodegenerative disorder, which will play an increasingly important role both socially and financially in the aging populations. Treatments for AD show modest improvements in cognition and global functioning among patients. Furthermore, the oral administration of treating AD has had some drawbacks that decrease the medication adherence and efficacy of the therapy. Transdermal drugs are proposed as an alternative remedy to overcome the disadvantages of current pharmaceutical dosage options for this chronic disorder. They could have different strengths, such as offering a stable diffusion of active substance, avoiding the first pass metabolism, and reducing system adverse reactions. This article reviews the technical principles, novel techniques of transdermal delivery drug, and prospects for future development for the management of cognitive and behavioral dysfunctions in AD patients.

  10. The current state of industry development in Ukraine: advance perspective

    Directory of Open Access Journals (Sweden)

    Skyba Maryna Valeriyivna

    2015-02-01

    Full Text Available The current state of the industry of Ukraine are considered at the article. The author determined that the stabilization of the situation and further development of the industry need first of all cessation of hostilities. It is necessary to implement effective measures to combat corruption, the development of consistent, constructive and concerted action on the formation of institutions guaranteeing stability, predictability and transparency of the market rules and procedures that minimize the impact of shadow factors, and implementation of professional privatization and limitation of monopoly at the markets, forming a transparent, competitive business environment, the introduction of new energy saving technologies. These measures will help attract investment, increase production and improve enterprise profitability.

  11. Advanced power flow technologies for high current ICF accelerators

    International Nuclear Information System (INIS)

    VanDevender, J.P.; McDaniel, D.H.

    1978-01-01

    Two new technologies for raising the power density in high current, inertial confinement fusion accelerators have been developed in the past two years. Magnetic flashover inhibition utilizes the self-magnetic fields around the vacuum insulator surface to inhibit surface flashover; average electric fields of 40 Mv/m at magnetic fields of 1.1 T have been achieved. Self-magnetic insulation of long, vacuum transmission lines has been used to transport power at 1.6 x 10 14 W/m 2 over six meters and up to 1.6 x 10 15 W/m 2 over short distances in a radial anode-cathode feed. The recent data relevant to these new technologies and their implications for ICF will be explored

  12. Advanced therapy medicinal products: current and future perspectives.

    Science.gov (United States)

    Hanna, Eve; Rémuzat, Cécile; Auquier, Pascal; Toumi, Mondher

    2016-01-01

    Advanced therapy medicinal products (ATMPs) are innovative therapies that encompass gene therapy, somatic cell therapy, and tissue-engineered products. These therapies are expected to bring important health benefits, but also to substantially impact the pharmaceuticals budget. The aim of this study was to characterise the ATMPs in development and discuss future implications in terms of market access. Clinical trials were searched in the following databases: EudraCT (EU Drug Regulating Authorities Clinical Trials), ClinicalTrials.gov, and ICTRP (International Clinical Trials Registry Platform of the World Health Organization). Trials were classified by category of ATMP as defined by European regulation EC No. 1394/2007, as well as by development phase and disease area. The database search identified 939 clinical trials investigating ATMPs (85% ongoing, 15% completed). The majority of trials were in the early stages (Phase I, I/II: 64.3%, Phase II, II/III: 27.9%, Phase 3: 6.9%). Per category of ATMP, we identified 53.6% of trials for somatic cell therapies, 22.8% for tissue-engineered products, 22.4% for gene therapies, and 1.2% for combined products (incorporating a medical device). Disease areas included cancer (24.8%), cardiovascular diseases (19.4%), musculoskeletal (10.5%), immune system and inflammation (11.5%), neurology (9.1%), and others. Of the trials, 47.2% enrolled fewer than 25 patients. Due to the complexity and specificity of ATMPs, new clinical trial methodologies are being considered (e.g., small sample size, non-randomised trials, single-arm trials, surrogate endpoints, integrated protocols, and adaptive designs). Evidence generation post-launch will become unavoidable to address payers' expectations. ATMPs represent a fast-growing field of interest. Although most of the products are in an early development phase, the combined trial phase and the potential to cure severe chronic conditions suggest that ATMPs may reach the market earlier than

  13. Preemptive analgesia II: recent advances and current trends.

    LENUS (Irish Health Repository)

    Kelly, D J

    2012-02-03

    PURPOSE: This two-part review summarizes the current knowledge of physiological mechanisms, pharmacological modalities and controversial issues surrounding preemptive analgesia. SOURCE: Articles from 1966 to present were obtained from the MEDLINE databases. Search terms included analgesia, preemptive; neurotransmitters; pain, postoperative; hyperalgesia; sensitization, central nervous system; pathways, nociception; anesthetic techniques; analgesics, agents. Principal findings: In Part I of this review article, techniques and agents that attenuate or prevent central and peripheral sensitization were reviewed. In Part II, the conditions required for effective preemptive techniques are evaluated. Specifically, preemptive analgesia may be defined as an antinociceptive treatment that prevents establishment of altered central processing of afferent input from sites of injury. The most important conditions for establishment of effective preemptive analgesia are the establishment of an effective level of antinociception before injury, and the continuation of this effective analgesic level well into the post-injury period to prevent central sensitization during the inflammatory phase. Although single-agent therapy may attenuate the central nociceptive processing, multi-modal therapy is more effective, and may be associated with fewer side effects compared with the high-dose, single-agent therapy. CONCLUSION: The variable patient characteristics and timing of preemptive analgesia in relation to surgical noxious input require individualization of the technique(s) chosen. Multi-modal analgesic techniques appear more effective.

  14. Cutaneous wound healing: Current concepts and advances in wound care

    Directory of Open Access Journals (Sweden)

    Kenneth C Klein

    2014-01-01

    Full Text Available A non-healing wound is defined as showing no measurable signs of healing for at least 30 consecutive treatments with standard wound care. [1] It is a snapshot of a patient′s total health as well as the ongoing battle between noxious factors and the restoration of optimal macro and micro circulation, oxygenation and nutrition. In practice, standard therapies for non-healing cutaneous wounds include application of appropriate dressings, periodic debridement and eliminating causative factors. [2] The vast majority of wounds would heal by such approach with variable degrees of residual morbidity, disability and even mortality. Globally, beyond the above therapies, newer tools of healing are selectively accessible to caregivers, for various logistical or financial reasons. Our review will focus on the use of hyperbaric oxygen therapy (HBOT, as used at our institution (CAMC, and some other modalities that are relatively accessible to patients. HBOT is a relatively safe and technologically simpler way to deliver care worldwide. However, the expense for including HBOT as standard of care for recognized indications per UHMS(Undersea and Hyperbaric Medical Society may vary widely from country to country and payment system. [3] In the USA, CMS (Centers for Medicare and Medicaid Services approved indications for HBOT vary from that of the UHMS for logistical reasons. [1] We shall also briefly look into other newer therapies per current clinical usage and general acceptance by the medical community. Admittedly, there would be other novel tools with variable success in wound healing worldwide, but it would be difficult to include all in this treatise.

  15. Current advances on ABC drug transporters in fish.

    Science.gov (United States)

    Luckenbach, Till; Fischer, Stephan; Sturm, Armin

    2014-09-01

    Most members of the large ATP-binding cassette (ABC) gene family are transporters involved in substrate translocation across biological membranes. In eukaryotes, ABC proteins functioning as drug transporters are located in the plasma membrane and mediate the cellular efflux of a wide range of organic chemicals, with some transporters also transporting certain metals. As the enhanced expression of ABC drug transporters can confer multidrug resistance (MDR) to cancers and multixenobiotic resistance (MXR) to organisms from polluted habitats, these ABC family members are also referred to as MDR or MXR proteins. In mammals, ABC drug transporters show predominant expression in tissues involved in excretion or constituting internal or external body boundaries, where they facilitate the excretion of chemicals and their metabolites, and limit chemical uptake and penetration into "sanctuary" sites of the body. Available knowledge about ABC proteins is still limited in teleost fish, a large vertebrate group of high ecological and economic importance. Using transport activity measurements and immunochemical approaches, early studies demonstrated similarities in the tissue distribution of ABC drug transporters between teleosts and mammals, suggesting conserved roles of the transporters in the biochemical defence against toxicants. Recently, the availability of teleost genome assemblies has stimulated studies of the ABC family in this taxon. This review summarises the current knowledge regarding the genetics, functional properties, physiological function, and ecotoxicological relevance of teleostean ABC transporters. The available literature is reviewed with emphasis on recent studies addressing the tissue distribution, substrate spectrum, regulation, physiological function and phylogenetic origin of teleostean ABC transporters. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Cutaneous wound healing: Current concepts and advances in wound care

    Science.gov (United States)

    Klein, Kenneth C; Guha, Somes Chandra

    2014-01-01

    A non-healing wound is defined as showing no measurable signs of healing for at least 30 consecutive treatments with standard wound care.[1] It is a snapshot of a patient's total health as well as the ongoing battle between noxious factors and the restoration of optimal macro and micro circulation, oxygenation and nutrition. In practice, standard therapies for non-healing cutaneous wounds include application of appropriate dressings, periodic debridement and eliminating causative factors.[2] The vast majority of wounds would heal by such approach with variable degrees of residual morbidity, disability and even mortality. Globally, beyond the above therapies, newer tools of healing are selectively accessible to caregivers, for various logistical or financial reasons. Our review will focus on the use of hyperbaric oxygen therapy (HBOT), as used at our institution (CAMC), and some other modalities that are relatively accessible to patients. HBOT is a relatively safe and technologically simpler way to deliver care worldwide. However, the expense for including HBOT as standard of care for recognized indications per UHMS(Undersea and Hyperbaric Medical Society) may vary widely from country to country and payment system.[3] In the USA, CMS (Centers for Medicare and Medicaid Services) approved indications for HBOT vary from that of the UHMS for logistical reasons.[1] We shall also briefly look into other newer therapies per current clinical usage and general acceptance by the medical community. Admittedly, there would be other novel tools with variable success in wound healing worldwide, but it would be difficult to include all in this treatise. PMID:25593414

  17. 75 FR 51437 - Notice of Request for Extension of a Currently Approved Information Collection (Advanced Meat...

    Science.gov (United States)

    2010-08-20

    ... Request for Extension of a Currently Approved Information Collection (Advanced Meat Recovery) AGENCY: Food... information collection regarding the regulatory requirements associated with the production of meat from Advanced Meat Recovery systems because the OMB approval will expire on January 31, 2011. DATES: Comments on...

  18. Anaerobic biodegradability of macropollutants

    DEFF Research Database (Denmark)

    Angelidaki, Irini

    2002-01-01

    A variety of test procedures for determination of anaerobic biodegradability has been reported. This paper reviews the methods developed for determination of anaerobic biodegradability of macro-pollutants. Anaerobic biodegradability of micro-pollutants is not included. Furthermore, factors...

  19. Biodegradation and bioremediation

    DEFF Research Database (Denmark)

    Albrechtsen, H.-J.

    1996-01-01

    Anmeldelse af Alexander,M.: Biodegradation and bioremediation. Academic Press, Sandiego, USA, 1994......Anmeldelse af Alexander,M.: Biodegradation and bioremediation. Academic Press, Sandiego, USA, 1994...

  20. First results on fast wave current drive in advanced tokamak discharges in DIII-D

    International Nuclear Information System (INIS)

    Prater, R.; Cary, W.P.; Baity, F.W.

    1995-07-01

    Initial experiments have been performed on the DIII-D tokamak on coupling, direct electron heating, and current drive by fast waves in advanced tokamak discharges. These experiments showed efficient central heating and current drive in agreement with theory in magnitude and profile. Extrapolating these results to temperature characteristic of a power plant (25 keV) gives current drive efficiency of about 0.3 MA/m 2

  1. [Current recommendations for basic/advanced life support : Addressing unanswered questions and future prospects].

    Science.gov (United States)

    Fink, K; Schmid, B; Busch, H-J

    2016-11-01

    The revised guidelines for cardiopulmonary resuscitation were implemented by the European Resuscitation Council (ERC) in October 2015. There were few changes concerning basic and advanced life support; however, some issues were clarified compared to the ERC recommendations from 2010. The present paper summarizes the procedures of basic and advanced life support according to the current guidelines and highlights the updates of 2015. Furthermore, the article depicts future prospects of cardiopulmonary resuscitation that may improve outcome of patients after cardiac arrest in the future.

  2. Biodegradation of gallotannins and ellagitannins.

    Science.gov (United States)

    Li, Mingshu; Kai, Yao; Qiang, He; Dongying, Jia

    2006-01-01

    Nowadays, many researches have been made on gallotannin biodegradation and have gained great success in further utilization. Some of industrial applications of these findings are in the production of tannase, the biotransformation of tannic acid to gallic acid or pyrogallol and detannification of food and fodder. Although ellagitannins have the typical C-C bound which is more difficult to be degraded than gallotannins, concerted efforts are still in progress to improve ellagitannin degradation and utilization. Currently, more attention is mainly focused on intestinal microflora biodegradation of tannins especially ellagitannins which can contribute to the definition of their bioavailability for both human beings and ruminants. Also there have been endeavours to utilize the tannin-degrading activity of different fungi for ellagitannin-rich biomass, which will facilitate application of tannin-degrading enzymes in strategies for improving industrial and livestock production. Due to the complicated structures of complex tannins and condensed tannins, the biodegradation of them is much more difficult and there are fewer researches on them. Therefore, the researches on the mechanisms of gallotannin and ellagitannin biodegradation can result in the overall understanding to the biodegradation of complex tannins and condensed tannins. Biodegradation of tannins is in an incipient stage and further studies have to be carried out to exploit the potential of various tannins for largescale applications in food, fodder, medicine and tannery effluent treatment. ((c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim).

  3. Simultaneous adsorption and biodegradation of synthetic melanoidin

    African Journals Online (AJOL)

    Being an antioxidant, melanoidin removal through purely biodegradation has been inadequate. Consequently, in the current study, simultaneous adsorption and biodegradation (SAB) was employed in a stirred tank system to remove melanoidin from synthetic wastewater. Mixed microbial consortium was immobilized onto ...

  4. Biodegradable polymers for electrospinning: towards biomedical applications.

    Science.gov (United States)

    Kai, Dan; Liow, Sing Shy; Loh, Xian Jun

    2014-12-01

    Electrospinning has received much attention recently due to the growing interest in nano-technologies and the unique material properties. This review focuses on recent progress in applying electrospinning technique in production of biodegradable nanofibers to the emerging field of biomedical. It first introduces the basic theory and parameters of nanofibers fabrication, with focus on factors affecting the morphology and fiber diameter of biodegradable nanofibers. Next, commonly electrospun biodegradable nanofibers are discussed, and the comparison of the degradation rate of nanoscale materials with macroscale materials are highlighted. The article also assesses the recent advancement of biodegradable nanofibers in different biomedical applications, including tissue engineering, drug delivery, biosensor and immunoassay. Future perspectives of biodegradable nanofibers are discussed in the last section, which emphasizes on the innovation and development in electrospinning of hydrogels nanofibers, pore size control and scale-up productions. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Locally Advanced Colon Cancer : Evaluation of Current Clinical Practice and Treatment Outcomes at the Population Level

    NARCIS (Netherlands)

    Klaver, Charlotte E. L.; Gietelink, Lieke; Bemelman, Willem A.; Wouters, Michel W. J. M.; Wiggers, Theo; Tollenaar, Rob A. E. M.; Tanis, Pieter J.

    Background: The goal of this study was to evaluate current clinical practice and treatment outcomes regarding locally advanced colon cancer (LACC) at the population level. Methods: Data were used from the Dutch Surgical Colorectal Audit from 2009 to 2014. A total of 34,527 patients underwent

  6. Locally Advanced Colon Cancer: Evaluation of Current Clinical Practice and Treatment Outcomes at the Population Level

    NARCIS (Netherlands)

    Klaver, Charlotte E. L.; Gietelink, Lieke; Bemelman, Willem A.; Wouters, Michel W. J. M.; Wiggers, Theo; Tollenaar, Rob A. E. M.; Tanis, Pieter J.

    2017-01-01

    Background: The goal of this study was to evaluate current clinical practice and treatment outcomes regarding locally advanced colon cancer (LACC) at the population level. Methods: Data were used from the Dutch Surgical Colorectal Audit from 2009 to 2014. A total of 34,527 patients underwent

  7. Analysis of Advanced Fuel Assemblies and Core Designs for the Current and Next Generations of LWRs

    International Nuclear Information System (INIS)

    Ragusa, Jean; Vierow, Karen

    2011-01-01

    The objective of the project is to design and analyze advanced fuel assemblies for use in current and future light water reactors and to assess their ability to reduce the inventory of transuranic elements, while preserving operational safety. The reprocessing of spent nuclear fuel can delay or avoid the need for a second geological repository in the US. Current light water reactor fuel assembly designs under investigation could reduce the plutonium inventory of reprocessed fuel. Nevertheless, these designs are not effective in stabilizing or reducing the inventory of minor actinides. In the course of this project, we developed and analyzed advanced fuel assembly designs with improved thermal transmutation capability regarding transuranic elements and especially minor actinides. These designs will be intended for use in thermal spectrum (e.g., current and future fleet of light water reactors in the US). We investigated various fuel types, namely high burn-up advanced mixed oxides and inert matrix fuels, in various geometrical designs that are compliant with the core internals of current and future light water reactors. Neutronic/thermal hydraulic effects were included. Transmutation efficiency and safety parameters were used to rank and down-select the various designs.

  8. Analysis of Advanced Fuel Assemblies and Core Designs for the Current and Next Generations of LWRs

    Energy Technology Data Exchange (ETDEWEB)

    Ragusa, Jean; Vierow, Karen

    2011-09-01

    The objective of the project is to design and analyze advanced fuel assemblies for use in current and future light water reactors and to assess their ability to reduce the inventory of transuranic elements, while preserving operational safety. The reprocessing of spent nuclear fuel can delay or avoid the need for a second geological repository in the US. Current light water reactor fuel assembly designs under investigation could reduce the plutonium inventory of reprocessed fuel. Nevertheless, these designs are not effective in stabilizing or reducing the inventory of minor actinides. In the course of this project, we developed and analyzed advanced fuel assembly designs with improved thermal transmutation capability regarding transuranic elements and especially minor actinides. These designs will be intended for use in thermal spectrum (e.g., current and future fleet of light water reactors in the US). We investigated various fuel types, namely high burn-up advanced mixed oxides and inert matrix fuels, in various geometrical designs that are compliant with the core internals of current and future light water reactors. Neutronic/thermal hydraulic effects were included. Transmutation efficiency and safety parameters were used to rank and down-select the various designs.

  9. Current status of advanced gastrointestinal endoscopy training fellowships in the United States

    Directory of Open Access Journals (Sweden)

    Stephen J Heller

    2011-01-01

    Full Text Available Stephen J Heller, Jeffrey L TokarDepartment of Medicine, Fox Chase Cancer Center, Philadelphia, PA, USAAbstract: Rapid growth in the field of advanced gastrointestinal endoscopy has led to an increase in specialized therapeutic endoscopy fellowships. The cornerstones of these programs are training in endoscopic retrograde cholangiopancreatography (ERCP and endoscopic ultrasound. These procedures are more complex and challenging to master than routine colonoscopy and upper endoscopy, and in the case of ERCP, higher risk. The concentration of the educational experience in the hands of relatively fewer trainees with specialized interest in advanced endoscopy has resulted in providing a focused cohort of graduating fellows with higher case volumes in training, which likely enhances diagnostic and therapeutic success and safer performance of these procedures. Endoscopic simulators, although not currently in widespread use, have the potential to improve advanced procedural training without jeopardizing patient safety.Keywords: gastrointestinal endoscopy, training, procedures, safety 

  10. IMS advances in studies of field-aligned currents and their related electrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Kamide, Y.

    1985-12-01

    During the IMS period, there have been major advances in four areas regarding field-aligned currents which directly reflect the electrical coupling between the magnetosphere and the ionosphere. First, the spatial distribution of the large-scale field-aligned currents (in particular, their average configuration) has been extensively examined with respect to IMF (interplanetary magnetic field) parameters. The role of the field-aligned currents in the dayside polar cap including their IMF B/sub y/ dependence and seasonal dependence has been cleared to some extent. It remains to be answered, however, if the substorm pattern differs uniquely from the average disturbed pattern. Second, the three-dimensional current system has been studied by using satellite and ground-based, as well as radar, measurements. The nature of the substorm current system, which changes quite dynamically depending upon the different substorm phases as well as upon different auroral forms, has been more clearly defined. A third major advance has been in the efforts to find the relative location of the field-aligned currents to various ionospheric parameters, such as electric fields, conductivities, and discrete and diffuse auroras. Finally, numerical simulations of assumptions have increasingly become a powerful tool for the study of the dynamics of the magnetosphere-ionosphere system. It appears that the large-scale characteristics of the system under steady state conditions are known in the sense that the measured key parameters are mutually consistent for average data sets.

  11. The impact of H2O2 and the role of mineralization in biodegradation or ecotoxicity assessment of advanced oxidation processes

    Science.gov (United States)

    Sági, Gyuri; Bezsenyi, Anikó; Kovács, Krisztina; Klátyik, Szandra; Darvas, Béla; Székács, András; Wojnárovits, László; Takács, Erzsébet

    2018-03-01

    AOP are in the focus of interest as a result of their high efficiency in persistent organic pollutant removal. In the vast majority of experiments targeting quantification of changes in biodegradability or toxicity, conclusions are drawn by a simple comparison of solutions obtained at different stages of the oxidation. These results do not express properly the toxic potential or biodegradability of distinctive product groups, due to performing investigations without taking into account the decrease of organic content caused by mineralization. Moreover, the presence of H2O2 is very often also neglected, although it usually exerts strong interfering effects in the analytical methods applied routinely. The aim of present study was to draw attention towards these effects. In this work, the H2O2 content was removed by catalytic decomposition with MnO2, while exposure to equal pollutant concentrations was achieved by setting the solutions to equal COD or TOC values. Results obtained in such way (biological approach) have been compared to data obtained by neglecting both factors (technological approach). Biodegradation and ecotoxicity experiments were performed on the example of 0.1 mmol dm-3 sulfamethoxazole solutions oxidized during gamma irradiation. Significant differences were evidenced between the two approaches. Technological approach indicted only moderate transformation to bioavailable substances (BOD5 COD-1 = 0.33), while the biological approach referred to ready biodegradability (0.82). Ecotoxicity assessment performed with Vibrio fischeri bacteria demonstrated differences not only in the extent but also in the tendency of inhibition changes. In order to make reliable ecotoxicity assays, the H2O2 concentrations should be reduced to at least 0.05 mmol dm-3 in V. fischeri and P. subcapitata experiments, while, practically complete removal is needed in case of D. magna. In BOD measurements performed by manometric techniques, reducing the H2O2 concentration to at

  12. Neurogenic thoracic outlet syndrome: current diagnostic criteria and advances in MRI diagnostics.

    Science.gov (United States)

    Magill, Stephen T; Brus-Ramer, Marcel; Weinstein, Philip R; Chin, Cynthia T; Jacques, Line

    2015-09-01

    Neurogenic thoracic outlet syndrome (nTOS) is caused by compression of the brachial plexus as it traverses from the thoracic outlet to the axilla. Diagnosing nTOS can be difficult because of overlap with other complex pain and entrapment syndromes. An nTOS diagnosis is made based on patient history, physical exam, electrodiagnostic studies, and, more recently, interpretation of MR neurograms with tractography. Advances in high-resolution MRI and tractography can confirm an nTOS diagnosis and identify the location of nerve compression, allowing tailored surgical decompression. In this report, the authors review the current diagnostic criteria, present an update on advances in MRI, and provide case examples demonstrating how MR neurography (MRN) can aid in diagnosing nTOS. The authors conclude that improved high-resolution MRN and tractography are valuable tools for identifying the source of nerve compression in patients with nTOS and can augment current diagnostic modalities for this syndrome.

  13. Advances based on digital technology named TEDDY+ for inspection of eddy current

    International Nuclear Information System (INIS)

    Barcenilla, V.; Hernandez, J.; Ribes, B.

    2007-01-01

    As a result of the recent developing line of eddy current data acquisition system a new product based on digital technology named TEDDY+, comes to the market. With only 4 kg of weight constitutes a great advance with regards to other equipment's available in the market. These advances, have enabled, among others, to increase considerably the signal to noise (S/N) ratio, avoid typical saturation problems in the eddy current signal, increase the inspection speed, eliminate the reference probe, detect the air/tube signal in real time, and the possibility to integrate the tester inside a push puller thanks to its reduced size and to have integrated as part of the ET equipment the mechanical systems control board. Two product lines have been developed, one oriented to any market and application (nuclear market, industrial and aeronautical, chemical and petrochemical, etc) and other specially dedicated to the massive inspection of tubes, named TEDDY+SP (Suitcase Pusher). Both lines are prepared to use eddy current arrays which clearly constitute the future of the eddy current inspection systems. The new TEDDY+ line of products presented in this paper constitutes one of the most powerful and reliable existing in the market. These improvements and novelties place the new ET inspection system from Tecnatom as one of the most powerful and reliable in the market. (Author)

  14. Warfighter nutrition: current opportunities and advanced technologies report from a Department of Defense workshop.

    Science.gov (United States)

    Deuster, Patricia A; Weinstein, Ali A; Sobel, Annette; Young, Andrew J

    2009-07-01

    The Uniformed Services University hosted a conference in July 2008 entitled "Warfighter Nutrition: Advanced Technologies and Opportunities" with Health Affairs and the Defense Advanced Research Projects Agency to develop strategic and tactical plans that could enhance Force Health Protection (FHP) by optimizing warfighter nutrition within the Department of Defense (DoD). The conference focused on three aspects of military nutrition: (1) fueling the forces, or garrison feeding; (2) performance optimization or operational feeding during deployment; and (3) nutritional interventions to support health reset and healing. Presentations by speakers addressed practical interventions (i.e., ready for implementation now) and advanced technologies (i.e., approaches meriting prioritized research and development efforts to transition into application). The conference concluded that nutritional optimization represents an integral and proactive approach to prevent illness, injury, and performance degradation throughout all phases of military service. The overarching consensus achieved was that warfighter nutrition, as a cornerstone of FHP, warrants the critical attention of both medical and line leadership to move quickly to support current initiatives and future advanced technologies.

  15. Current status of environmental, health, and safety issues of electrochemical capacitors for advanced vehicle applications

    Energy Technology Data Exchange (ETDEWEB)

    Vimmerstedt, L J; Hammel, C J

    1997-04-01

    Electrochemical capacitors are a candidate for traction power assists in hybrid electric vehicles (HEVs). Other advanced automotive applications, while not the primary focus of current development efforts, are also possible. These include load leveling high-energy batteries, power conditioning electronics, electrically hated catalysts, electric power steering, and engine starter power. Higher power and longer cycle life are expected for electrochemical capacitors than for batteries. Evaluation of environmental, health, and safety (EH and S) issues of electrochemical capacitors is an essential part of the development and commercialization of electrochemical capacitors for advanced vehicles. This report provides an initial EH and S assessment. This report presents electrochemical capacitor electrochemistry, materials selection, intrinsic material hazards, mitigation of those hazards, environmental requirements, pollution control options, and shipping requirements. Most of the information available for this assessment pertains to commercial devices intended for application outside the advanced vehicle market and to experiment or prototype devices. Electrochemical capacitors for power assists in HEVs are not produced commercially now. Therefore, materials for advanced vehicle electrochemical capacitors may change, and so would the corresponding EH and S issues. Although changes are possible, this report describes issues for likely electrochemical capacitor designs.

  16. Human immune responses against Shigella and enterotoxigenic E. coli: Current advances and the path forward.

    Science.gov (United States)

    McArthur, Monica A; Maciel, Milton; Pasetti, Marcela F

    2017-12-14

    Robust and well-established immunological assays and firm immune correlates of protection that can predict disease outcome and/or vaccine efficacy are essential to adequately assess human immune responses to infection and vaccination. The availability of reagents and calibrated controls is also critically important to standardize assays and generate comparable results among different laboratories. The workshop "Human Immune Responses against Shigella and ETEC: Current Advances and the Path Forward" held during the VASE meeting provided an opportunity to disseminate and discuss recent advances in the field of Shigella and ETEC immunology, identify research needs, and propose collaborative activities to advance the field. Four presentations featured current knowledge on humoral and cellular immune responses to Shigella and ETEC during infection and vaccination. A discussion followed on immunological methods relevant for clinical studies, immune parameters associated with protection, harmonization of assays among laboratories, and availability of reagents and standards. Specific recommendations proposed to facilitate "the path forward" included supporting communication among scientists, harmonization of assays and sharing of protocols, the creation of a repository of reagents and calibrated controls and distribution of such material to the research community, and expansion of exploratory studies to better understand the interactions between these pathogens and the human immune system and the ensuing responses. Copyright © 2017. Published by Elsevier Ltd.

  17. Design of the beam shut-off current monitor upgrade for the Advanced Photon Source

    International Nuclear Information System (INIS)

    Pietryla, A.; Decker, G.

    2000-01-01

    Plans to eliminate the positron accumulator ring (PAR) from the Advanced Photon Source (APS) injector complex have created the need for a device to limit the allowable beam charge injected into the APS injector synchrotrons. The beam shut-off current monitor (BESOCM) was chosen to provide this function. This new application of the BESOCM provided the opportunity to explore new design philosophies. Two design goals were to de-emphasize reliance on external signals and to become insensitive to timing variations. Both of these goals were accomplished by deriving the trigger directly from the beam. This paper will discuss the features of the new BESOCM design and present data demonstrating its function

  18. Advanced alarm system design and human performance: Guidance development and current research

    International Nuclear Information System (INIS)

    O'Hara, J.M.

    1997-01-01

    This paper describes a research program sponsored by the U.S. Nuclear Regulatory Commission to address the human factors engineering (HFE) aspects of nuclear power plant alarm systems. The overall objective of the program is to develop HFE review guidance for advanced alarm systems. Guidance has been developed based on a broad base of technical and research literature. As part of the development effort, aspects of alarm system design for which the technical basis was insufficient to support guidance development were identified and prioritized. Research is currently underway to address the highest priority topics: alarm processing and display characteristics. (author). 29 refs, 2 figs

  19. Biodegradation of phenol | Nair | African Journal of Biotechnology

    African Journals Online (AJOL)

    Biodegradation of phenol. CI Nair, K Jayachandran, S Shashidhar. Abstract. The use of microbial catalysts in the biodegradation of organic compounds has advanced significantly during the past three decades. It has been found that large numbers of microbes co-exist in almost all natural environments, particularly in soils.

  20. Current advances and trends in electro-Fenton process using heterogeneous catalysts - A review.

    Science.gov (United States)

    Poza-Nogueiras, Verónica; Rosales, Emilio; Pazos, Marta; Sanromán, M Ángeles

    2018-06-01

    Over the last decades, advanced oxidation processes have often been used alone, or combined with other techniques, for remediation of ground and surface water pollutants. The application of heterogeneous catalysis to electrochemical advanced oxidation processes is especially useful due to its efficiency and environmental safety. Among those processes, electro-Fenton stands out as the one in which heterogeneous catalysis has been broadly applied. Thus, this review has introduced an up-to-date collation of the current knowledge of the heterogeneous electro-Fenton process, highlighting recent advances in the use of different catalysts such as iron minerals (pyrite, magnetite or goethite), prepared catalysts by the load of metals in inorganic and organic materials, nanoparticles, and the inclusion of catalysts on the cathode. The effects of physical-chemical parameters as well as the mechanisms involved are critically assessed. Finally, although the utilization of this process to remediation of wastewater overwhelmingly outnumber other utilities, several applications have been described in the context of regeneration of adsorbent or the remediation of soils as clear examples of the feasibility of the electro-Fenton process to solve different environmental problems. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Advances in Wound Healing: A Review of Current Wound Healing Products

    Directory of Open Access Journals (Sweden)

    Patrick S. Murphy

    2012-01-01

    Full Text Available Successful wound care involves optimizing patient local and systemic conditions in conjunction with an ideal wound healing environment. Many different products have been developed to influence this wound environment to provide a pathogen-free, protected, and moist area for healing to occur. Newer products are currently being used to replace or augment various substrates in the wound healing cascade. This review of the current state of the art in wound-healing products looks at the latest applications of silver in microbial prophylaxis and treatment, including issues involving resistance and side effects, the latest uses of negative pressure wound devices, advanced dressings and skin substitutes, biologic wound products including growth factor applications, and hyperbaric oxygen as an adjunct in wound healing. With the abundance of available products, the goal is to find the most appropriate modality or combination of modalities to optimize healing.

  2. Safety design features for current UK advanced gas-cooled reactors

    International Nuclear Information System (INIS)

    Yellowlees, J.M.; Cobb, E.C.

    1981-01-01

    The nuclear power stations planned for Heysham II and Torness will each have twin 660 MW(e) Advanced Gas-cooled Reactors (AGR) based on the design of those which have been operating at Hinkley Point 'B' and Hunterston 'B' since 1976. This paper has described the way in which the shutdown and cooling systems for the Heysham II and Torness AGRs have been selected in order to meet current UK safety requirements. Fault tree analyses have been used to identify the credible fault sequences, the probabilities of which have been calculated. By this means the relative importance of the various protective systems has been established and redundancy and reliability requirements identified. This systematic approach has led to a balanced design giving protection over the complete spectrum of fault sequences. Current safety requirements for thermal reactors in the UK and particular requirements in the design of the Heysham II and Torness reactors are discussed

  3. Corneal stem cells and tissue engineering: Current advances and future perspectives.

    Science.gov (United States)

    de Araujo, Aline Lütz; Gomes, José Álvaro Pereira

    2015-06-26

    Major advances are currently being made in regenerative medicine for cornea. Stem cell-based therapies represent a novel strategy that may substitute conventional corneal transplantation, albeit there are many challenges ahead given the singularities of each cellular layer of the cornea. This review recapitulates the current data on corneal epithelial stem cells, corneal stromal stem cells and corneal endothelial cell progenitors. Corneal limbal autografts containing epithelial stem cells have been transplanted in humans for more than 20 years with great successful rates, and researchers now focus on ex vivo cultures and other cell lineages to transplant to the ocular surface. A small population of cells in the corneal endothelium was recently reported to have self-renewal capacity, although they do not proliferate in vivo. Two main obstacles have hindered endothelial cell transplantation to date: culture protocols and cell delivery methods to the posterior cornea in vivo. Human corneal stromal stem cells have been identified shortly after the recognition of precursors of endothelial cells. Stromal stem cells may have the potential to provide a direct cell-based therapeutic approach when injected to corneal scars. Furthermore, they exhibit the ability to deposit organized connective tissue in vitro and may be useful in corneal stroma engineering in the future. Recent advances and future perspectives in the field are discussed.

  4. Current status of selected oral peptide technologies in advanced preclinical development and in clinical trials.

    Science.gov (United States)

    Aguirre, T A S; Teijeiro-Osorio, D; Rosa, M; Coulter, I S; Alonso, M J; Brayden, D J

    2016-11-15

    The development of oral dosage forms that allows absorption of therapeutic peptides to the systemic circulation is one of the greatest challenges for the pharmaceutical industry. Currently, a number of technologies including either mixtures of penetration enhancers or protease inhibitors and/or nanotechnology-based products are under clinical development. Typically, these formulations are presented in the form of enteric-coated tablets or capsules. Systems undergoing preclinical investigation include further advances in nanotechnology, including intestinal microneedle patches, as well as their combination with regional delivery to the colon. This review critically examines four selected promising oral peptide technologies at preclinical stage and the twelve that have progressed to clinical trials, as indicated in www.clinicaltrials.gov. We examined these technologies under the criteria of peptide selection, formulation design, system components and excipients, intestinal mechanism of action, efficacy in man, and safety issues. The conclusion is that most of the technologies in clinical trials are incremental rather than paradigm-shifting and that even the more clinically advanced oral peptide drugs examples of oral bioavailability appear to yield oral bioavailability values of only 1-2% and are, therefore, only currently suitable for a limited range of peptides. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. JSC Advanced Curation: Research and Development for Current Collections and Future Sample Return Mission Demands

    Science.gov (United States)

    Fries, M. D.; Allen, C. C.; Calaway, M. J.; Evans, C. A.; Stansbery, E. K.

    2015-01-01

    Curation of NASA's astromaterials sample collections is a demanding and evolving activity that supports valuable science from NASA missions for generations, long after the samples are returned to Earth. For example, NASA continues to loan hundreds of Apollo program samples to investigators every year and those samples are often analyzed using instruments that did not exist at the time of the Apollo missions themselves. The samples are curated in a manner that minimizes overall contamination, enabling clean, new high-sensitivity measurements and new science results over 40 years after their return to Earth. As our exploration of the Solar System progresses, upcoming and future NASA sample return missions will return new samples with stringent contamination control, sample environmental control, and Planetary Protection requirements. Therefore, an essential element of a healthy astromaterials curation program is a research and development (R&D) effort that characterizes and employs new technologies to maintain current collections and enable new missions - an Advanced Curation effort. JSC's Astromaterials Acquisition & Curation Office is continually performing Advanced Curation research, identifying and defining knowledge gaps about research, development, and validation/verification topics that are critical to support current and future NASA astromaterials sample collections. The following are highlighted knowledge gaps and research opportunities.

  6. Biodegradable and compostable alternatives to conventional plastics.

    Science.gov (United States)

    Song, J H; Murphy, R J; Narayan, R; Davies, G B H

    2009-07-27

    Packaging waste forms a significant part of municipal solid waste and has caused increasing environmental concerns, resulting in a strengthening of various regulations aimed at reducing the amounts generated. Among other materials, a wide range of oil-based polymers is currently used in packaging applications. These are virtually all non-biodegradable, and some are difficult to recycle or reuse due to being complex composites having varying levels of contamination. Recently, significant progress has been made in the development of biodegradable plastics, largely from renewable natural resources, to produce biodegradable materials with similar functionality to that of oil-based polymers. The expansion in these bio-based materials has several potential benefits for greenhouse gas balances and other environmental impacts over whole life cycles and in the use of renewable, rather than finite resources. It is intended that use of biodegradable materials will contribute to sustainability and reduction in the environmental impact associated with disposal of oil-based polymers. The diversity of biodegradable materials and their varying properties makes it difficult to make simple, generic assessments such as biodegradable products are all 'good' or petrochemical-based products are all 'bad'. This paper discusses the potential impacts of biodegradable packaging materials and their waste management, particularly via composting. It presents the key issues that inform judgements of the benefits these materials have in relation to conventional, petrochemical-based counterparts. Specific examples are given from new research on biodegradability in simulated 'home' composting systems. It is the view of the authors that biodegradable packaging materials are most suitable for single-use disposable applications where the post-consumer waste can be locally composted.

  7. Biodegradable and compostable alternatives to conventional plastics

    Science.gov (United States)

    Song, J. H.; Murphy, R. J.; Narayan, R.; Davies, G. B. H.

    2009-01-01

    Packaging waste forms a significant part of municipal solid waste and has caused increasing environmental concerns, resulting in a strengthening of various regulations aimed at reducing the amounts generated. Among other materials, a wide range of oil-based polymers is currently used in packaging applications. These are virtually all non-biodegradable, and some are difficult to recycle or reuse due to being complex composites having varying levels of contamination. Recently, significant progress has been made in the development of biodegradable plastics, largely from renewable natural resources, to produce biodegradable materials with similar functionality to that of oil-based polymers. The expansion in these bio-based materials has several potential benefits for greenhouse gas balances and other environmental impacts over whole life cycles and in the use of renewable, rather than finite resources. It is intended that use of biodegradable materials will contribute to sustainability and reduction in the environmental impact associated with disposal of oil-based polymers. The diversity of biodegradable materials and their varying properties makes it difficult to make simple, generic assessments such as biodegradable products are all ‘good’ or petrochemical-based products are all ‘bad’. This paper discusses the potential impacts of biodegradable packaging materials and their waste management, particularly via composting. It presents the key issues that inform judgements of the benefits these materials have in relation to conventional, petrochemical-based counterparts. Specific examples are given from new research on biodegradability in simulated ‘home’ composting systems. It is the view of the authors that biodegradable packaging materials are most suitable for single-use disposable applications where the post-consumer waste can be locally composted. PMID:19528060

  8. Critical evaluation of biodegradable polymers used in nanodrugs

    Science.gov (United States)

    Marin, Edgar; Briceño, Maria Isabel; Caballero-George, Catherina

    2013-01-01

    Use of biodegradable polymers for biomedical applications has increased in recent decades due to their biocompatibility, biodegradability, flexibility, and minimal side effects. Applications of these materials include creation of skin, blood vessels, cartilage scaffolds, and nanosystems for drug delivery. These biodegradable polymeric nanoparticles enhance properties such as bioavailability and stability, and provide controlled release of bioactive compounds. This review evaluates the classification, synthesis, degradation mechanisms, and biological applications of the biodegradable polymers currently being studied as drug delivery carriers. In addition, the use of nanosystems to solve current drug delivery problems are reviewed. PMID:23990720

  9. Critical evaluation of biodegradable polymers used in nanodrugs.

    Science.gov (United States)

    Marin, Edgar; Briceño, Maria Isabel; Caballero-George, Catherina

    2013-01-01

    Use of biodegradable polymers for biomedical applications has increased in recent decades due to their biocompatibility, biodegradability, flexibility, and minimal side effects. Applications of these materials include creation of skin, blood vessels, cartilage scaffolds, and nanosystems for drug delivery. These biodegradable polymeric nanoparticles enhance properties such as bioavailability and stability, and provide controlled release of bioactive compounds. This review evaluates the classification, synthesis, degradation mechanisms, and biological applications of the biodegradable polymers currently being studied as drug delivery carriers. In addition, the use of nanosystems to solve current drug delivery problems are reviewed.

  10. Biodegradation of Polypropylene Nonwovens

    Science.gov (United States)

    Keene, Brandi Nechelle

    The primary aim of the current research is to document the biodegradation of polypropylene nonwovens and filament under composting environments. To accelerate the biodegradat ion, pre-treatments and additives were incorporated into polypropylene filaments and nonwovens. The initial phase (Chapter 2) of the project studied the biodegradation of untreated polypropylene with/without pro-oxidants in two types of composting systems. Normal composting, which involved incubation of samples in food waste, had little effect on the mechanical properties of additive-free spunbond nonwovens in to comparison prooxidant containing spunbond nonwovens which were affected significantly. Modified composting which includes the burial of samples with food and compressed air, the polypropylene spunbond nonwovens with/without pro-oxidants displayed an extreme loss in mechanical properties and cracking on the surface cracking. Because the untreated spunbond nonwovens did not completely decompose, the next phase of the project examined the pre-treatment of gamma-irradiation or thermal aging prior to composting. After exposure to gamma-irradiation and thermal aging, polypropylene is subjected to oxidative degradation in the presence of air and during storage after irradiat ion. Similar to photo-oxidation, the mechanism of gamma radiation and thermal oxidative degradation is fundamentally free radical in nature. In Chapter 3, the compostability of thermal aged spunbond polypropylene nonwovens with/without pro-oxidant additives. The FTIR spectrum confirmed oxidat ion of the polypropylene nonwovens with/without additives. Cracking on both the pro-oxidant and control spunbond nonwovens was showed by SEM imaging. Spunbond polypropylene nonwovens with/without pro-oxidants were also preirradiated by gamma rays followed by composting. Nonwovens with/without pro-oxidants were severely degraded by gamma-irradiation after up to 20 kGy exposure as explained in Chapter 4. Furthermore (Chapter 5), gamma

  11. Advanced antenna system for Alfven wave plasma heating and current drive in TCABR tokamak

    International Nuclear Information System (INIS)

    Ruchko, L.F.; Ozono, E.; Galvao, R.M.O.; Nascimento, I.C.; Degasperi, F.T.; Lerche, E.

    1998-01-01

    An advanced antenna system that has been developed for investigation of Alfven wave plasma heating and current drive in the TCABR tokamak is described. The main goal was the development of such a system that could insure the excitation of travelling single helicity modes with predefined wave mode numbers M and N. The system consists of four similar modules with poloidal windings. The required spatial spectrum is formed by proper phasing of the RF feeding currents. The impedance matching of the antenna with the four-phase oscillator is accomplished by resonant circuits which form one assembly unit with the RF feeders. The characteristics of the antenna system design with respect to the antenna-plasma coupling and plasma wave excitation, for different phasing of the feeding currents, are summarised. The antenna complex impedance Z=Z R +Z I is calculated taking into account both the plasma response to resonant excitation of fast Alfven waves and the nonresonant excitation of vacuum magnetic fields in conducting shell. The matching of the RF generator with the antenna system during plasma heating is simulated numerically, modelling the plasma response with mutually coupled effective inductances with corresponding active Z R and reactive Z I impedances. The results of the numerical simulation of the RF system performance, including both the RF magnetic field spectrum analysis and the modeling of the RF generator operation with plasma load, are presented. (orig.)

  12. Biodegradability and biodegradation pathways of endosulfan and endosulfan sulfate.

    Science.gov (United States)

    Kataoka, Ryota; Takagi, Kazuhiro

    2013-04-01

    Endosulfan and endosulfan sulfate are persistent organic pollutants that cause serious environmental problems. Although these compounds are already prohibited in many countries, residues can be detected in soils with a history of endosulfan application. Endosulfan is transformed in the environment into endosulfan sulfate, which is a toxic and persistent metabolite. However, some microorganisms can degrade endosulfan without producing endosulfan sulfate, and some can degrade endosulfan sulfate. Therefore, biodegradation has the potential to clean up soil contaminated with endosulfan. In this review, we provide an overview of aerobic endosulfan degradation by bacteria and fungi, and a summary of recent advances and prospects in this research field.

  13. Failure of the Current Advance Care Planning Paradigm: Advocating for a Communications-Based Approach.

    Science.gov (United States)

    Vearrier, Laura

    2016-12-01

    The purpose of advance care planning (ACP) is to allow an individual to maintain autonomy in end-of-life (EOL) medical decision-making even when incapacitated by disease or terminal illness. The intersection of EOL medical technology, ethics of EOL care, and state and federal law has driven the development of the legal framework for advance directives (ADs). However, from an ethical perspective the current legal framework is inadequate to make ADs an effective EOL planning tool. One response to this flawed AD process has been the development of Physician Orders for Life Sustaining Treatment (POLST). POLST has been described as a paradigm shift to address the inadequacies of ADs. However, POLST has failed to bridge the gap between patients and their autonomous, preferred EOL care decisions. Analysis of ADs and POLST reveals that future policy should focus on a communications-based approach to ACP that emphasizes ongoing interactions between healthcare providers and patients to optimize EOL medical care to the individual patient.

  14. An eddy-current model for three-dimensional nondestructive evaluation of advanced composites

    Science.gov (United States)

    Sabbagh, Harold A.; Murphy, R. Kim; Sabbagh, Elias H.

    2015-03-01

    We have developed a rigorous electromagnetic model and an inversion algorithm for the three-dimensional NDE of advanced composite materials. This approach extends Victor Technologies' work in eddy-current NDE of conventional metals, and allows one to determine in localized regions the fiber-resin ratio in graphite-epoxy, and to determine those anomalies, e.g., delaminations, broken fibers, moisture content, etc., that can be reconstructed by our inversion method. In developing the model, we apply rigorous electromagnetic theory to determine a Green's function for a slab of anisotropic composite material, and then determine the integral relations for the forward and inverse problems using the Green's function. We will give examples of the solution of forward problems using this model.

  15. Advances for prosthetic technology from historical perspective to current status to future application

    CERN Document Server

    LeMoyne, Robert

    2016-01-01

    This book focuses on the advances in transtibial prosthetic technology and targets research in the evolution of the powered prosthesis such as the BiOM, which was derived from considerable research and development at the Massachusetts Institute of Technology. The concept of the book spans the historical evolution of prosthetic applications from passive to new and futuristic robotic prosthetic technologies.  The author describes the reasons for amputation, surgical procedures, and an historical perspective of the prosthesis for the lower limb. He also addresses the phases and sub-phases of gait and compensatory mechanisms arising for a transtibial prosthesis and links the compensatory mechanisms to long-term morbidities.  The general technologies for gait analysis central to prosthetic design and the inherent biomechanics foundations for analysis are also explored.  The book reports on recent-past to current-term applications with passive elastic prostheses.  The core of the book deals with futuristic robo...

  16. Current Animal Models of Postoperative Spine Infection and Potential Future Advances

    Directory of Open Access Journals (Sweden)

    Alexandra eStavrakis

    2015-05-01

    Full Text Available Implant related infection following spine surgery is a devastating complication for patients and can potentially lead to significant neurological compromise, disability, morbidity, and even mortality. This paper provides an overview of the existing animal models of postoperative spine infection and highlights the strengths and weaknesses of each model. In addition there is discussion regarding potential modifications to these animal models to better evaluate preventative and treatment strategies for this challenging complication. Current models are effective in simulating surgical procedures but fail to evaluate infection longitudinally using multiple techniques. Potential future modifications to these models include using advanced imaging technologies to evaluate infection, use of bioluminescent bacterial species, and testing of novel treatment strategies against multiple bacterial strains. There is potential to establish a postoperative spine infection model using smaller animals, such as mice, as these would be a more cost-effective screening tool for potential therapeutic interventions.

  17. Current Advancements and Strategies in Tissue Engineering for Wound Healing: A Comprehensive Review.

    Science.gov (United States)

    Ho, Jasmine; Walsh, Claire; Yue, Dominic; Dardik, Alan; Cheema, Umber

    2017-06-01

    Significance: With an aging population leading to an increase in diabetes and associated cutaneous wounds, there is a pressing clinical need to improve wound-healing therapies. Recent Advances: Tissue engineering approaches for wound healing and skin regeneration have been developed over the past few decades. A review of current literature has identified common themes and strategies that are proving successful within the field: The delivery of cells, mainly mesenchymal stem cells, within scaffolds of the native matrix is one such strategy. We overview these approaches and give insights into mechanisms that aid wound healing in different clinical scenarios. Critical Issues: We discuss the importance of the biomimetic niche, and how recapitulating elements of the native microenvironment of cells can help direct cell behavior and fate. Future Directions: It is crucial that during the continued development of tissue engineering in wound repair, there is close collaboration between tissue engineers and clinicians to maintain the translational efficacy of this approach.

  18. Continuous micro-current stimulation to upgrade methanolic wastewater biodegradation and biomethane recovery in an upflow anaerobic sludge blanket (UASB) reactor.

    Science.gov (United States)

    Zhen, Guangyin; Lu, Xueqin; Kobayashi, Takuro; Su, Lianghu; Kumar, Gopalakrishnan; Bakonyi, Péter; He, Yan; Sivagurunathan, Periyasamy; Nemestóthy, Nándor; Xu, Kaiqin; Zhao, Youcai

    2017-08-01

    The dispersion of granules in upflow anaerobic sludge blanket (UASB) reactor represents a critical technical issue in methanolic wastewater treatment. In this study, the potentials of coupling a microbial electrolysis cell (MEC) into an UASB reactor for improving methanolic wastewater biodegradation, long-term process stability and biomethane recovery were evaluated. The results indicated that coupling a MEC system was capable of improving the overall performance of UASB reactor for methanolic wastewater treatment. The combined system maintained the comparatively higher methane yield and COD removal efficiency over the single UASB process through the entire process, with the methane production at the steady-state conditions approaching 1504.7 ± 92.2 mL-CH 4 L -1 -reactor d -1 , around 10.1% higher than the control UASB (i.e. 1366.4 ± 71.0 mL-CH 4 L -1 -reactor d -1 ). The further characterizations verified that the input of external power source could stimulate the metabolic activity of microbes and reinforced the EPS secretion. The produced EPS interacted with Fe 2+/3+ liberated during anodic corrosion of iron electrode to create a gel-like three-dimensional [-Fe-EPS-] n matrix, which promoted cell-cell cohesion and maintained the structural integrity of granules. Further observations via SEM and FISH analysis demonstrated that the use of bioelectrochemical stimulation promoted the growth and proliferation of microorganisms, which diversified the degradation routes of methanol, convert the wasted CO 2 into methane and accordingly increased the process stability and methane productivity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Forensic engineering of advanced polymeric materials Part IV: Case study of oxo-biodegradable polyethylene commercial bag - Aging in biotic and abiotic environment.

    Science.gov (United States)

    Musioł, Marta; Rydz, Joanna; Janeczek, Henryk; Radecka, Iza; Jiang, Guozhan; Kowalczuk, Marek

    2017-06-01

    The public awareness of the quality of environment stimulates the endeavor to safe polymeric materials and their degradation products. The aim of the forensic engineering case study presented in this paper is to evaluate the aging process of commercial oxo-degradable polyethylene bag under real industrial composting conditions and in distilled water at 70°C, for comparison. Partial degradation of the investigated material was monitored by changes in molecular weight, thermal properties and Keto Carbonyl Bond Index and Vinyl Bond Index, which were calculated from the FTIR spectra. The results indicate that such an oxo-degradable product offered in markets degrades slowly under industrial composting conditions. Even fragmentation is slow, and it is dubious that biological mineralization of this material would occur within a year under industrial composting conditions. The slow degradation and fragmentation is most likely due to partially crosslinking after long time of degradation, which results in the limitation of low molecular weight residues for assimilation. The work suggests that these materials should not be labeled as biodegradable, and should be further analyzed in order to avoid the spread of persistent artificial materials in nature. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. GRAPEVINE VIRUS DISEASES:ECONOMIC IMPACT AND CURRENT ADVANCES IN VIRAL PROSPECTION AND MANAGEMENT

    Directory of Open Access Journals (Sweden)

    MARCOS FERNANDO BASSO

    Full Text Available ABSTRACT Grapevine (Vitis spp. is a major vegetative propagated fruit crop with high socioeconomic importance worldwide. It is susceptible to several graft-transmitted agents that cause several diseases and substantial crop losses, reducing fruit quality and plant vigor, and shorten the longevity of vines. The vegetative propagation and frequent exchanges of propagative material among countries contribute to spread these pathogens, favoring the emergence of complex diseases. Its perennial life cycle further accelerates the mixing and introduction of several viral agents into a single plant. Currently, approximately 65 viruses belonging to different families have been reported infecting grapevines, but not all cause economically relevant diseases. The grapevine leafroll, rugose wood complex, leaf degeneration and fleck diseases are the four main disorders having worldwide economic importance. In addition, new viral species and strains have been identified and associated with economically important constraints to grape production. In Brazilian vineyards, eighteen viruses, three viroids and two virus-like diseases had already their occurrence reported and were molecularly characterized. Here, we review the current knowledge of these viruses, report advances in their diagnosis and prospection of new species, and give indications about the management of the associated grapevine diseases.

  1. Current Advance and Future Prospects of Tissue Engineering Approach to Dentin/Pulp Regenerative Therapy

    Directory of Open Access Journals (Sweden)

    Ting Gong

    2016-01-01

    Full Text Available Recent advances in biomaterial science and tissue engineering technology have greatly spurred the development of regenerative endodontics. This has led to a paradigm shift in endodontic treatment from simply filling the root canal systems with biologically inert materials to restoring the infected dental pulp with functional replacement tissues. Currently, cell transplantation has gained increasing attention as a scientifically valid method for dentin-pulp complex regeneration. This multidisciplinary approach which involves the interplay of three key elements of tissue engineering—stem cells, scaffolds, and signaling molecules—has produced an impressive number of favorable outcomes in preclinical animal studies. Nevertheless, many practical hurdles need to be overcome prior to its application in clinical settings. Apart from the potential health risks of immunological rejection and pathogenic transmission, the lack of a well-established banking system for the isolation and storage of dental-derived stem cells is the most pressing issue that awaits resolution and the properties of supportive scaffold materials vary across different studies and remain inconsistent. This review critically examines the classic triad of tissue engineering utilized in current regenerative endodontics and summarizes the possible techniques developed for dentin/pulp regeneration.

  2. Current Advance and Future Prospects of Tissue Engineering Approach to Dentin/Pulp Regenerative Therapy

    Science.gov (United States)

    Gong, Ting; Heng, Boon Chin; Lo, Edward Chin Man; Zhang, Chengfei

    2016-01-01

    Recent advances in biomaterial science and tissue engineering technology have greatly spurred the development of regenerative endodontics. This has led to a paradigm shift in endodontic treatment from simply filling the root canal systems with biologically inert materials to restoring the infected dental pulp with functional replacement tissues. Currently, cell transplantation has gained increasing attention as a scientifically valid method for dentin-pulp complex regeneration. This multidisciplinary approach which involves the interplay of three key elements of tissue engineering—stem cells, scaffolds, and signaling molecules—has produced an impressive number of favorable outcomes in preclinical animal studies. Nevertheless, many practical hurdles need to be overcome prior to its application in clinical settings. Apart from the potential health risks of immunological rejection and pathogenic transmission, the lack of a well-established banking system for the isolation and storage of dental-derived stem cells is the most pressing issue that awaits resolution and the properties of supportive scaffold materials vary across different studies and remain inconsistent. This review critically examines the classic triad of tissue engineering utilized in current regenerative endodontics and summarizes the possible techniques developed for dentin/pulp regeneration. PMID:27069484

  3. Current status on advanced aqueous reprocessing process (next) in FaCT project

    International Nuclear Information System (INIS)

    Washiya, Tadahiro; Myochin, Munetaka; Koyama, Tomozo

    2009-01-01

    Japan Atomic Energy Agency (JAEA) launched the Fast Reactor Cycle Technology Development (FaCT) project in cooperation with the Japanese electric utilities in 2006. An integration of the advanced aqueous reprocessing concept and the simplified pelletizing fuel fabrication was selected as the most promising fuel cycle system. In order to accomplish the integration, R and D tasks were launched as FaCT Project in 2006 by Japanese joint team. The New Extraction System for TRU Recovery (NEXT) system is an advanced aqueous reprocessing concept which was based on the well established aqueous reprocessing for LWR spent fuel and newly applied processes such as uranium crystallization and extraction chromatography for MAs recovery. Main task of the NEXT process is to develop the TRU recovery process and equipments with high reliability, criticality safety, high durability and remote maintainability. In the FaCT project, all innovative technologies are planned to be developed within the next decade focusing on the future commercialization of FBR cycle systems. The judgment of the adoption of each innovative technology will be made by 2010 based on the results of R and Ds. The development of each technology is to be completed by around 2015. By the same time, it is scheduled to present the conceptual design of commercial and demonstrative fast reactor cycle facilities. The six items (Disassembling and shearing, Fuel dissolution, Uranium Crystallization, Single cycle co-extraction of U, Pu and Np, MA recovery by extraction chromatography and Waste treatment) have been identified as the issues to be developed corresponding to each process step. Current R and D status and prospects of this system until around 2015 is reported. (author)

  4. An advanced current control compensation scheme to improve the microgrid power quality without using dedicated compensation devices

    DEFF Research Database (Denmark)

    Naderipour, A.; Zin, A. A.Mohd; Habibuddin, M. H.

    2016-01-01

    of the harmonics in Microgrid (MG) and between MG and Power Common Coupling (PCC). The current harmonics in the grid and MG are compensated without using dedicated compensation devices, such as active power filters (APFs), by the proposed current controller which is contain an advanced synchronous reference frame...

  5. Biobased and biodegradable polymer nanocomposites

    Science.gov (United States)

    Qiu, Kaiyan

    In this dissertation, various noncrosslinked and crosslinked biobased and biodegradable polymer nanocomposites were fabricated and characterized. The properties of these polymer nanocomposites, and their relating mechanisms and corresponding applications were studied and discussed in depth. Chapter 1 introduces the research background and objectives of the current research. Chapter 2 presents the development of a novel low cost carbon source for bacterial cellulose (BC) production and fabrication and characterization of biobased polymer nanocomposites using produced BC and soy protein based resins. The carbon source, soy flour extract (SFE), was obtained from defatted soy flour (SF) and BC yield achieved using SFE medium was high. The results of this study showed that SFE consists of five sugars and Acetobacter xylinum metabolized sugars in a specific order. Chapter 3 discusses the fabrication and characterization of biodegradable polymer nanocomposites using BC and polyvinyl alcohol (PVA). These polymer nanocomposites had excellent tensile and thermal properties. Crosslinking of PVA using glutaraldehyde (GA) not only increased the mechanical and thermal properties but the water-resistance. Chapter 4 describes the development and characterization of microfibrillated cellulose (MFC) based biodegradable polymer nanocomposites by blending MFC suspension with PVA. Chemical crosslinking of the polymer nanocomposites was carried out using glyoxal to increase the mechanical and thermal properties as well as to make the PVA partially water-insoluble. Chapter 5 reports the development and characterization of halloysite nanotube (HNT) reinforced biodegradable polymer nanocomposites utilizing HNT dispersion and PVA. Several separation techniques were used to obtain individualized HNT dispersion. The results indicated uniform dispersion of HNTs in both PVA and malonic acid (MA) crosslinked PVA resulted in excellent mechanical and thermal properties of the materials, especially

  6. Advanced thermal-hydraulic and neutronic codes: current and future applications. Summary and conclusions

    International Nuclear Information System (INIS)

    2001-05-01

    An OECD Workshop on Advanced Thermal-Hydraulic and Neutronic Codes Applications was held from 10 to 13 April 2000, in Barcelona, Spain, sponsored by the Committee on the Safety of Nuclear Installations (CSNI) of the OECD Nuclear Energy Agency (NEA). It was organised in collaboration with the Spanish Nuclear Safety Council (CSN) and hosted by CSN and the Polytechnic University of Catalonia (UPC) in collaboration with the Spanish Electricity Association (UNESA). The objectives of the Workshop were to review the developments since the previous CSNI Workshop held in Annapolis [NEA/CSNI/ R(97)4; NUREG/CP-0159], to analyse the present status of maturity and remnant needs of thermal-hydraulic (TH) and neutronic system codes and methods, and finally to evaluate the role of these tools in the evolving regulatory environment. The Technical Sessions and Discussion Sessions covered the following topics: - Regulatory requirements for Best-Estimate (BE) code assessment; - Application of TH and neutronic codes for current safety issues; - Uncertainty analysis; - Needs for integral plant transient and accident analysis; - Simulators and fast running codes; - Advances in next generation TH and neutronic codes; - Future trends in physical modeling; - Long term plans for development of advanced codes. The focus of the Workshop was on system codes. An incursion was made, however, in the new field of applying Computational Fluid Dynamic (CFD) codes to nuclear safety analysis. As a general conclusion, the Barcelona Workshop can be considered representative of the progress towards the targets marked at Annapolis almost four years ago. The Annapolis Workshop had identified areas where further development and specific improvements were needed, among them: multi-field models, transport of interfacial area, 2D and 3D thermal-hydraulics, 3-D neutronics consistent with level of details of thermal-hydraulics. Recommendations issued at Annapolis included: developing small pilot/test codes for

  7. Proceedings of the workshop on advanced thermal-hydraulic and neutronic codes: current and future applications

    International Nuclear Information System (INIS)

    2001-01-01

    An OECD Workshop on Advanced Thermal-Hydraulic and Neutronic Codes Applications was held from 10 to 13 April 2000, in Barcelona, Spain, sponsored by the Committee on the Safety of Nuclear Installations (CSNI) of the OECD Nuclear Energy Agency (NEA). It was organised in collaboration with the Spanish Nuclear Safety Council (CSN) and hosted by CSN and the Polytechnic University of Catalonia (UPC) in collaboration with the Spanish Electricity Association (UNESA). The objectives of the Workshop were to review the developments since the previous CSNI Workshop held in Annapolis [NEA/CSNI/ R(97)4; NUREG/CP-0159], to analyse the present status of maturity and remnant needs of thermal-hydraulic (TH) and neutronic system codes and methods, and finally to evaluate the role of these tools in the evolving regulatory environment. The Technical Sessions and Discussion Sessions covered the following topics: - Regulatory requirements for Best-Estimate (BE) code assessment; - Application of TH and neutronic codes for current safety issues; - Uncertainty analysis; - Needs for integral plant transient and accident analysis; - Simulators and fast running codes; - Advances in next generation TH and neutronic codes; - Future trends in physical modeling; - Long term plans for development of advanced codes. The focus of the Workshop was on system codes. An incursion was made, however, in the new field of applying Computational Fluid Dynamic (CFD) codes to nuclear safety analysis. As a general conclusion, the Barcelona Workshop can be considered representative of the progress towards the targets marked at Annapolis almost four years ago. The Annapolis Workshop had identified areas where further development and specific improvements were needed, among them: multi-field models, transport of interfacial area, 2D and 3D thermal-hydraulics, 3-D neutronics consistent with level of details of thermal-hydraulics. Recommendations issued at Annapolis included: developing small pilot/test codes for

  8. Grey water biodegradability.

    Science.gov (United States)

    Ghunmi, Lina Abu; Zeeman, Grietje; Fayyad, Manar; van Lier, Jules B

    2011-02-01

    Knowing the biodegradability characteristics of grey water constituents is imperative for a proper design and operation of a biological treatment system of grey water. This study characterizes the different COD fractions of dormitory grey water and investigates the effect of applying different conditions in the biodegradation test. The maximum aerobic and anaerobic biodegradability and conversion rate for the different COD fractions is determined. The results show that, on average, dormitory grey water COD fractions are 28% suspended, 32% colloidal and 40% dissolved. The studied factors incubation time, inoculum addition and temperature are influencing the determined biodegradability. The maximum biodegradability and biodegradation rate differ between different COD fractions, viz. COD(ss), COD(col) and COD(diss). The dissolved COD fraction is characterised by the lowest degradation rate, both for anaerobic and aerobic conditions. The maximum biodegradability for aerobic and anaerobic conditions is 86 and 70% respectively, whereas the first order conversion rate constant, k₂₀, is 0.119 and 0.005 day⁻¹, respectively. The anaerobic and aerobic conversion rates in relation to temperature can be described by the Arrhenius relation, with temperature coefficients of 1.069 and 1.099, respectively.

  9. Malignant gliomas: current perspectives in diagnosis, treatment, and early response assessment using advanced quantitative imaging methods

    Directory of Open Access Journals (Sweden)

    Ahmed R

    2014-03-01

    Full Text Available Rafay Ahmed,1 Matthew J Oborski,2 Misun Hwang,1 Frank S Lieberman,3 James M Mountz11Department of Radiology, 2Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA; 3Department of Neurology and Department of Medicine, Division of Hematology/Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USAAbstract: Malignant gliomas consist of glioblastomas, anaplastic astrocytomas, anaplastic oligodendrogliomas and anaplastic oligoastrocytomas, and some less common tumors such as anaplastic ependymomas and anaplastic gangliogliomas. Malignant gliomas have high morbidity and mortality. Even with optimal treatment, median survival is only 12–15 months for glioblastomas and 2–5 years for anaplastic gliomas. However, recent advances in imaging and quantitative analysis of image data have led to earlier diagnosis of tumors and tumor response to therapy, providing oncologists with a greater time window for therapy management. In addition, improved understanding of tumor biology, genetics, and resistance mechanisms has enhanced surgical techniques, chemotherapy methods, and radiotherapy administration. After proper diagnosis and institution of appropriate therapy, there is now a vital need for quantitative methods that can sensitively detect malignant glioma response to therapy at early follow-up times, when changes in management of nonresponders can have its greatest effect. Currently, response is largely evaluated by measuring magnetic resonance contrast and size change, but this approach does not take into account the key biologic steps that precede tumor size reduction. Molecular imaging is ideally suited to measuring early response by quantifying cellular metabolism, proliferation, and apoptosis, activities altered early in treatment. We expect that successful integration of quantitative imaging biomarker assessment into the early phase of clinical trials could provide a novel approach for testing new therapies

  10. Advanced simulation capability for environmental management - current status and future applications

    International Nuclear Information System (INIS)

    Freshley, Mark; Scheibe, Timothy; Robinson, Bruce; Moulton, J. David; Dixon, Paul; Marble, Justin; Gerdes, Kurt; Stockton, Tom; Seitz, Roger; Black, Paul

    2013-01-01

    The U.S. Department of Energy (US DOE) Office of Environmental Management (EM), Office of Soil and Groundwater (EM-12), is supporting development of the Advanced Simulation Capability for Environmental Management (ASCEM). ASCEM is a state-of-the-art scientific tool and approach that is currently aimed at understanding and predicting contaminant fate and transport in natural and engineered systems. ASCEM is a modular and open source high-performance computing tool. It will be used to facilitate integrated approaches to modeling and site characterization, and provide robust and standardized assessments of performance and risk for EM cleanup and closure activities. The ASCEM project continues to make significant progress in development of capabilities, with current emphasis on integration of capabilities in FY12. Capability development is occurring for both the Platform and Integrated Tool-sets and High-Performance Computing (HPC) multi-process simulator. The Platform capabilities provide the user interface and tools for end-to-end model development, starting with definition of the conceptual model, management of data for model input, model calibration and uncertainty analysis, and processing of model output, including visualization. The HPC capabilities target increased functionality of process model representations, tool-sets for interaction with Platform, and verification and model confidence testing. The integration of the Platform and HPC capabilities were tested and evaluated for EM applications in a set of demonstrations as part of Site Applications Thrust Area activities in 2012. The current maturity of the ASCEM computational and analysis capabilities has afforded the opportunity for collaborative efforts to develop decision analysis tools to support and optimize radioactive waste disposal. Recent advances in computerized decision analysis frameworks provide the perfect opportunity to bring this capability into ASCEM. This will allow radioactive waste

  11. High Current ESD Test of Advanced Triple Junction Solar Array Coupon

    Science.gov (United States)

    Wright, Kenneth H., Jr.; Schneider, Todd A.; Vaughn, Jason A.; Hoang, Bao; Wong, Frankie

    2015-01-01

    A test was conducted on an Advanced Triple Junction (ATJ) coupon that was part of a risk reduction effort in the development of a high-powered solar array design by SSL. The ATJ coupon was a small, 4-cell, two-string configuration that has served as the basic test coupon design used in previous SSL environmental aging campaigns. The coupon has many attributes of the flight design; e.g., substrate structure with graphite face sheets, integrated by-pass diodes, cell interconnects, RTV grout, wire routing, etc. The objective of the present test was to evaluate the performance of the coupon after being subjected to induced electrostatic discharge testing at two string voltages (100 V, 150 V) and four array current (1.65 A, 2.0 A, 2.475 A, and 3.3 A). An ESD test circuit, unique to SSL solar array design, was built that simulates the effect of missing cells and strings in a full solar panel with special primary arc flashover circuitry. A total of 73 primary arcs were obtained that included 7 temporary sustained arcs (TSA) events. The durations of the TSAs ranged from 50 micros to 2.9 ms. All TSAs occurred at a string voltage of 150 V. Post-test Large Area Pulsed Solar Simulator (LAPSS), Dark I-V, and By-Pass Diode tests showed that no degradation occurred due to the TSA events. In addition, the post-test insulation resistance measured was > 50 G-ohms between cells and substrate. These test results indicate a robust design for application to a high-current, high-power mission application.

  12. Methods for Evaluating the Biodegradability of Environmentally Degradable Polymers

    NARCIS (Netherlands)

    Zee, van der M.

    2014-01-01

    This chapter presents an overview of the current knowledge on experimental methods for monitoring the biodegradability of polymeric materials. The focus is, in particular, on the biodegradation of materials under environmental conditions. Examples of in vivo degradation of polymers used in

  13. Spermatogonial stem cells: Current biotechnological advances in reproduction and regenerative medicine.

    Science.gov (United States)

    Aponte, Pedro Manuel

    2015-05-26

    Spermatogonial stem cells (SSCs) are the germ stem cells of the seminiferous epithelium in the testis. Through the process of spermatogenesis, they produce sperm while concomitantly keeping their cellular pool constant through self-renewal. SSC biology offers important applications for animal reproduction and overcoming human disease through regenerative therapies. To this end, several techniques involving SSCs have been developed and will be covered in this article. SSCs convey genetic information to the next generation, a property that can be exploited for gene targeting. Additionally, SSCs can be induced to become embryonic stem cell-like pluripotent cells in vitro. Updates on SSC transplantation techniques with related applications, such as fertility restoration and preservation of endangered species, are also covered on this article. SSC suspensions can be transplanted to the testis of an animal and this has given the basis for SSC functional assays. This procedure has proven technically demanding in large animals and men. In parallel, testis tissue xenografting, another transplantation technique, was developed and resulted in sperm production in testis explants grafted into ectopical locations in foreign species. Since SSC culture holds a pivotal role in SSC biotechnologies, current advances are overviewed. Finally, spermatogenesis in vitro, already demonstrated in mice, offers great promises to cope with reproductive issues in the farm animal industry and human clinical applications.

  14. Clinical Applications of Contrast-Enhanced Perfusion MRI Techniques in Gliomas: Recent Advances and Current Challenges

    Directory of Open Access Journals (Sweden)

    Junfeng Zhang

    2017-01-01

    Full Text Available Gliomas possess complex and heterogeneous vasculatures with abnormal hemodynamics. Despite considerable advances in diagnostic and therapeutic techniques for improving tumor management and patient care in recent years, the prognosis of malignant gliomas remains dismal. Perfusion-weighted magnetic resonance imaging techniques that could noninvasively provide superior information on vascular functionality have attracted much attention for evaluating brain tumors. However, nonconsensus imaging protocols and postprocessing analysis among different institutions impede their integration into standard-of-care imaging in clinic. And there have been very few studies providing a comprehensive evidence-based and systematic summary. This review first outlines the status of glioma theranostics and tumor-associated vascular pathology and then presents an overview of the principles of dynamic contrast-enhanced MRI (DCE-MRI and dynamic susceptibility contrast-MRI (DSC-MRI, with emphasis on their recent clinical applications in gliomas including tumor grading, identification of molecular characteristics, differentiation of glioma from other brain tumors, treatment response assessment, and predicting prognosis. Current challenges and future perspectives are also highlighted.

  15. Modeling interfacial glass-water reactions: recent advances and current limitations

    International Nuclear Information System (INIS)

    Pierce, Eric M.; Frugier, Pierre; Criscenti, Louise J.; Kwon, Kideok D.; Kerisit, Sebastien N.

    2014-01-01

    Describing the reactions that occur at the glass-water interface and control the development of the altered layer constitutes one of the main scientific challenges impeding existing models from providing accurate radionuclide release estimates. Radionuclide release estimates are a critical component of the safety basis for geologic repositories. The altered layer (i.e., amorphous hydrated surface layer and crystalline reaction products) represents a complex region, both physically and chemically, sandwiched between two distinct boundaries-pristine glass surface at the inner most interface and aqueous solution at the outer most interface. Computational models, spanning different length and timescales, are currently being developed to improve our understanding of this complex and dynamic process with the goal of accurately describing the mesoscale changes that occur as the system evolves. These modeling approaches include geochemical simulations (i.e., classical reaction path simulations and glass reactivity in allowance for alteration layer simulations), Monte Carlo simulations, and molecular dynamics methods. Discussed in this manuscript are the advances and limitations of each modeling approach placed in the context of the glass-water reaction and how collectively these approaches provide insights into the mechanisms that control the formation and evolution of altered layers. New results are presented as examples of each approach. (authors)

  16. Biodegradable modified Phba systems

    International Nuclear Information System (INIS)

    Aniscenko, L.; Dzenis, M.; Erkske, D.; Tupureina, V.; Savenkova, L.; Muizniece - Braslava, S.

    2004-01-01

    Compositions as well as production technology of ecologically sound biodegradable multicomponent polymer systems were developed. Our objective was to design some bio plastic based composites with required mechanical properties and biodegradability intended for use as biodegradable packaging. Significant characteristics required for food packaging such as barrier properties (water and oxygen permeability) and influence of γ-radiation on the structure and changes of main characteristics of some modified PHB matrices was evaluated. It was found that barrier properties were plasticizers chemical nature and sterilization with γ-radiation dependent and were comparable with corresponding values of typical polymeric packaging films. Low γ-radiation levels (25 kGy) can be recommended as an effective sterilization method of PHB based packaging materials. Purposely designed bio plastic packaging may provide an alternative to traditional synthetic packaging materials without reducing the comfort of the end-user due to specific qualities of PHB - biodegradability, Biocompatibility and hydrophobic nature

  17. Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project: Current and advanced act control system definition study

    Science.gov (United States)

    1982-01-01

    The Current and Advanced Technology ACT control system definition tasks of the Integrated Application of Active Controls (IAAC) Technology project within the Energy Efficient Transport Program are summarized. The systems mechanize six active control functions: (1) pitch augmented stability; (2) angle of attack limiting; (3) lateral/directional augmented stability; (4) gust load alleviation; (5) maneuver load control; and (6) flutter mode control. The redundant digital control systems meet all function requirements with required reliability and declining weight and cost as advanced technology is introduced.

  18. Biodegradation: Updating the Concepts of Control for Microbial Cleanup in Contaminated Aquifers

    DEFF Research Database (Denmark)

    Meckenstock, Rainer U.; Elsner, Martin; Griebler, Christian

    2015-01-01

    critically discuss classical concepts such as the thermodynamic redox zonation, or the use of steady state transport scenarios for assessing biodegradation rates. Furthermore, we discuss if the absence of specific degrader populations can explain poor biodegradation. We propose updated perspectives...... on the controls of biodegradation in contaminant plumes. These include the plume fringe concept, transport limitations, and transient conditions as currently underestimated processes affecting biodegradation....

  19. Current advanced therapy cell-based medicinal products for type-1-diabetes treatment.

    Science.gov (United States)

    Cañibano-Hernández, Alberto; Del Burgo, Laura Sáenz; Espona-Noguera, Albert; Ciriza, Jesús; Pedraz, Jose Luis

    2018-03-27

    In the XXI century diabetes mellitus has become one of the main threats to human health with higher incidence in regions such as Europe and North America. Type 1 diabetes mellitus (T1DM) occurs as a consequence of the immune-mediated destruction of insulin producing β-cells located in the endocrine part of the pancreas, the islets of Langerhans. The administration of exogenous insulin through daily injections is the most prominent treatment for T1DM but its administration is frequently associated to failure in glucose metabolism control, finally leading to hyperglycemia episodes. Other approaches have been developed in the past decades, such as whole pancreas and islet allotransplantation, but they are restricted to patients who exhibit frequent episodes of hypoglycemia or renal failure because the lack of donors and islet survival. Moreover, patients transplanted with either whole pancreas or islets require of immune suppression to avoid the rejection of the transplant. Currently, advanced therapy medicinal products (ATMP), such as implantable devices, have been developed in order to reduce immune rejection response while increasing cell survival. To overcome these issues, ATMPs must promote vascularization, guaranteeing the nutritional contribution, while providing O 2 until vasculature can surround the device. Moreover, it should help in the immune-protection to avoid acute and chronic rejection. The transplanted cells or islets should be embedded within biomaterials with tunable properties like injectability, stiffness and porosity mimicking natural ECM structural characteristics. And finally, an infinitive cell source that solves the donor scarcity should be found such as insulin producing cells derived from mesenchymal stem cells (MSCs), embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). Several companies have registered their ATMPs and future studies envision new prototypes. In this review, we will discuss the mechanisms and etiology of

  20. The history of biodegradable magnesium implants: a review.

    Science.gov (United States)

    Witte, Frank

    2010-05-01

    Today, more than 200years after the first production of metallic magnesium by Sir Humphry Davy in 1808, biodegradable magnesium-based metal implants are currently breaking the paradigm in biomaterial science to develop only highly corrosion resistant metals. This groundbreaking approach to temporary metallic implants is one of the latest developments in biomaterials science that is being rediscovered. It is a challenging topic, and several secrets still remain that might revolutionize various biomedical implants currently in clinical use. Magnesium alloys were investigated as implant materials long ago. A very early clinical report was given in 1878 by the physician Edward C. Huse. He used magnesium wires as ligature for bleeding vessels. Magnesium alloys for clinical use were explored during the last two centuries mainly by surgeons with various clinical backgrounds, such as cardiovascular, musculoskeletal and general surgery. Nearly all patients benefited from the treatment with magnesium implants. Although most patients experienced subcutaneous gas cavities caused by rapid implant corrosion, most patients had no pain and almost no infections were observed during the postoperative follow-up. This review critically summarizes the in vitro and in vivo knowledge and experience that has been reported on the use of magnesium and its alloys to advance the field of biodegradable metals. Copyright (c) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  1. Reprint of: The history of biodegradable magnesium implants: A review.

    Science.gov (United States)

    Witte, Frank

    2015-09-01

    Today, more than 200 years after the first production of metallic magnesium by Sir Humphry Davy in 1808, biodegradable magnesium-based metal implants are currently breaking the paradigm in biomaterial science to develop only highly corrosion resistant metals. This groundbreaking approach to temporary metallic implants is one of the latest developments in biomaterials science that is being rediscovered. It is a challenging topic, and several secrets still remain that might revolutionize various biomedical implants currently in clinical use. Magnesium alloys were investigated as implant materials long ago. A very early clinical report was given in 1878 by the physician Edward C. Huse. He used magnesium wires as ligature for bleeding vessels. Magnesium alloys for clinical use were explored during the last two centuries mainly by surgeons with various clinical backgrounds, such as cardiovascular, musculoskeletal and general surgery. Nearly all patients benefited from the treatment with magnesium implants. Although most patients experienced subcutaneous gas cavities caused by rapid implant corrosion, most patients had no pain and almost no infections were observed during the postoperative follow-up. This review critically summarizes the in vitro and in vivo knowledge and experience that has been reported on the use of magnesium and its alloys to advance the field of biodegradable metals. Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  2. Pre-treatment technologies for dark fermentative hydrogen production: Current advances and future directions.

    Science.gov (United States)

    Rafieenia, Razieh; Lavagnolo, Maria Cristina; Pivato, Alberto

    2018-01-01

    Hydrogen is regarded as a clean and non-carbon fuel and it has a higher energy content compared to carbon fuels. Dark fermentative hydrogen production from organic wastes is the most promising technology for commercialization among chemical and biological methods. Using mixed microflora is favored in terms of easier process control and substrate conversion efficiencies instead of pure cultures. However, mixed cultures should be first pre-treated in order to select sporulating hydrogen producing bacteria and suppress non-spore forming hydrogen consumers. Various inoculum pre-treatments have been used to enhance hydrogen production by dark fermentation including heat shock, acid or alkaline treatment, chemical inhibition, aeration, irradiation and inhibition by long chain fatty acids. Regarding substrate pre-treatment, that is performed with the aim of enhanced substrate biodegradability, thermal pre-treatment, pH adjustment using acid or base, microwave irradiation, sonication and biological treatment are the most commonly studied technologies. This article reviews the most investigated pre-treatment technologies applied for either inoculum or substrate prior to dark fermentation, the long-term effects of varying pre-treatment methods and the subsequently feasibility of each method for commercialization. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project: Current and advanced act control system definition study. Volume 2: Appendices

    Science.gov (United States)

    Hanks, G. W.; Shomber, H. A.; Dethman, H. A.; Gratzer, L. B.; Maeshiro, A.; Gangsaas, D.; Blight, J. D.; Buchan, S. M.; Crumb, C. B.; Dorwart, R. J.

    1981-01-01

    The current status of the Active Controls Technology (ACT) for the advanced subsonic transport project is investigated through analysis of the systems technical data. Control systems technologies under examination include computerized reliability analysis, pitch axis fly by wire actuator, flaperon actuation system design trade study, control law synthesis and analysis, flutter mode control and gust load alleviation analysis, and implementation of alternative ACT systems. Extensive analysis of the computer techniques involved in each system is included.

  4. Current trends and recent advances in diagnosis, therapy, and prevention of hepatocellular carcinoma.

    Science.gov (United States)

    Wang, Chun-Hsiang; Wey, Keh-Cherng; Mo, Lein-Ray; Chang, Kuo-Kwan; Lin, Ruey-Chang; Kuo, Jen-Juan

    2015-01-01

    Hepatocellular carcinoma (HCC) has been one of the most fatal malignant tumors worldwide and its associated morbidity and mortality remain of significant concern. Based on in-depth reviews of serological diagnosis of HCC, in addition to AFP, there are other biomarkers: Lens culinaris agglutinin-reactive AFP (AFP-L3), des- carboxyprothrombin (DCP), tyrosine kinase with Ig and eprdermal growth factor (EGF) homology domains 2 (TIE2)-espressing monocytes (TEMs), glypican-3 (GPC3), Golgi protein 73 (GP73), interleukin-6 (IL-6), and squamous cell carcinoma antigen (SCCA) have been proposed as biomarkers for the early detection of HCC. The diagnosis of HCC is primarily based on noninvasive standard imaging methods, such as ultrasound (US), dynamic multiphasic multidetector-row CT (MDCT) and magnetic resonance imaging (MRI). Some experts advocate gadolinium diethyl-enetriamine pentaacetic acid (Gd-EOB-DTPA) MRI and contrast-enhanced US as the promising imaging madalities of choice. With regard to recent advancements in tissue markers, many cuting-edge technologies using genome-wide DNA microarrays, qRT-PCR, and proteomic and inmunostaining studies have been implemented in an attempt to identify markers for early diagnosis of HCC. Only less than half of HCC patients at initial diagnosis are at an early stage treatable with curative options: local ablation, surgical resection, or liver transplant. Transarterial chemoembolization (TACE) is considered the standard of care with palliation for intermediate stage HCC. Recent innovative procedures using drug-eluting-beads and radioembolization using Yttrium-90 may exhibit beneficial effects in HCC treatment. During the past few years, several molecular targeted agents have been evaluated in clinical trials in advanced HCC. Sorafenib is currently the only approved systemic treatment for HCC. It has been approved for the therapy of asymptomatic HCC patients with well-preserved liver function who are not candidates for potentially

  5. Production of Polyhydroxyalkanoates, a bacterial biodegradable ...

    African Journals Online (AJOL)

    Administrator

    There has been considerable interest in the development and production of biodegradable polymer to solve the current problem of pollution caused ... horticultural agricultural waste, corn, cassava etc would be of economic interest considering the .... for efficient production of PHAs. (Yu, 2001, Du et al.,. 2001b; Du and Yu, ...

  6. Current and future studies of actinides materials at the advanced light source

    International Nuclear Information System (INIS)

    Shuh, D.K.

    2002-01-01

    The vacuum ultraviolet (VUV)/soft X-ray region of the synchrotron radiation (SR) spectrum has revolutionized the approach to surface materials chemistry/physics. This spectral region has long been recognised for its potential to afford investigations of fundamental actinide science and to provide an improved analytical surface characterisation capabilities for actinide materials. Previously, the actinide science community was unable to take advantage of the opportunities afforded by VUV/soft X-ray SR methodologies because of radiological safety concerns and the need to prepare pristine actinide materials compatible with experiments in ultra-high vacuum end stations. With the advent of third-generation light sources operating in the VUV/soft X-ray region, such as the Advanced Light Source (ALS) at LBNL, experiments with small amounts of actinide materials are possible. Actinide investigations at the ALS are based on a graded approach to radioactive materials safety and are conducted with the assistance of LBNL Environment, Health and Safety (EH and S) personnel during the experiments. LBNL EH and S personnel have many years of experience supporting experiments utilising radioactive materials at LBNL user-based accelerator facilities. The SR techniques and technologies used in this energy region have continued to mature, permitting more complicated investigations and enabling new spectroscopic approaches. Of particular importance for work with actinides is the development of the micro-spectroscopy and spectro-microscopy capabilities on several beamlines at the ALS. These capabilities allow the use of small amounts of actinide material. In addition, these techniques can provide information on the spatial distribution of actinide species that complements the spectral information. Early demonstrations of the ability to safely collect data from actinide micro-samples and the active support of the ALS for such experiments has led to the investigations of actinide

  7. Biodegradable nanoparticles for gene therapy technology

    International Nuclear Information System (INIS)

    Hosseinkhani, Hossein; He, Wen-Jie; Chiang, Chiao-Hsi; Hong, Po-Da; Yu, Dah-Shyong; Domb, Abraham J.; Ou, Keng-Liang

    2013-01-01

    Rapid propagations in materials technology together with biology have initiated great hopes in the possibility of treating many diseases by gene therapy technology. Viral and non-viral gene carriers are currently applied for gene delivery. Non-viral technology is safe and effective for the delivery of genetic materials to cells and tissues. Non-viral systems are based on plasmid expression containing a gene encoding a therapeutic protein and synthetic biodegradable nanoparticles as a safe carrier of gene. Biodegradable nanoparticles have shown great interest in drug and gene delivery systems as they are easy to be synthesized and have no side effect in cells and tissues. This review provides a critical view of applications of biodegradable nanoparticles on gene therapy technology to enhance the localization of in vitro and in vivo and improve the function of administered genes

  8. Engineered biosynthesis of biodegradable polymers.

    Science.gov (United States)

    Jambunathan, Pooja; Zhang, Kechun

    2016-08-01

    Advances in science and technology have resulted in the rapid development of biobased plastics and the major drivers for this expansion are rising environmental concerns of plastic pollution and the depletion of fossil-fuels. This paper presents a broad view on the recent developments of three promising biobased plastics, polylactic acid (PLA), polyhydroxyalkanoate (PHA) and polybutylene succinate (PBS), well known for their biodegradability. The article discusses the natural and recombinant host organisms used for fermentative production of monomers, alternative carbon feedstocks that have been used to lower production cost, different metabolic engineering strategies used to improve product titers, various fermentation technologies employed to increase productivities and finally, the different downstream processes used for recovery and purification of the monomers and polymers.

  9. Application of Advanced Technology to Improve Plant Performance. Safety and Performance in Current NPPs

    International Nuclear Information System (INIS)

    Hashemian, H.M.

    2011-01-01

    Advances in computer technologies, signal processing, analytical modeling, and the advent of wireless sensors have provided the nuclear industry with ample means to automate and optimize maintenance activities and improve safety, efficiency, and availability, while reducing costs and radiation exposure to maintenance personnel. This paper provides a review of these developments and presents examples of their use in the nuclear power industry and the financial and safety benefits that they have produced. As the current generation of nuclear power plants have passed their mid-life, increased monitoring of their health is critical to their safe operation. This is especially true now that license renewal of nuclear power plants has accelerated, allowing some plants to operate up to 60 years or more. Furthermore, many utilities are maximizing their power output through uprating projects and retrofits. This puts additional demand and more stress on the plant equipment such as the instrumentation and control (I and C) systems and the reactor internal components making them more vulnerable to the effects of aging, degradation, and failure. In the meantime, the nuclear power industry is working to reduce generation costs by adopting condition-based maintenance strategies and automation of testing activities. These developments have stimulated great interest in on-line monitoring (OLM) technologies and new diagnostic and prognostic methods to anticipate, identify, and resolve equipment and process problems and ensure plant safety, efficiency, and immunity to accidents. The foundation for much of the required technologies has already been established through 40 years of research and development (R and D) efforts performed by numerous organizations, scientists, and engineers around the world including the author. This paper provides examples of these technologies and demonstrates how the gap between some of the more important R and D efforts and end users have been filled

  10. Current status of the active test at RRP and development programs for the advanced melter

    International Nuclear Information System (INIS)

    Kanehira, Norio

    2016-01-01

    The vitrification facility in Rokkasho Reprocessing Plant started the active tests to solidify HAW into the glass in 2007 which was the examination of the final stage before the operation, but the active test had to be discontinued due to the trouble of glass melter operation with down of pouring by deposit of noble metals on the melter bottom. After the equipment and operating conditions were improved in response to the result of the mock-up tests, a series of active tests were restarted active tests in May, 2012. These tests were finished with enough confirmation of stability in the state such as glass temperature and controlling the noble metals. JNFL has been developed the advanced melter, Joule heated ceramic melter, and the design of the advanced melter is largely different from the existing one. For the confirmation of the advanced melter performances, the full-scale inactive tests had been performed and successfully finished. This paper describes outline of development for advanced melter in Rokkasho Reprocessing Plant. (author)

  11. Faculty Development for Advancing Community Engagement in Higher Education: Current Trends and Future Directions

    Science.gov (United States)

    Welch, Marshall; Plaxton-Moore, Star

    2017-01-01

    This research involved the conduct of a conceptual review of 28 refereed journal articles and a survey of campus centers for community engagement staff to identify salient features and trends of existing faculty development programming designed to advance service-learning and community engagement in higher education. Results of this investigation…

  12. A review on introduction and applications of starch and its biodegradable polymers

    OpenAIRE

    Shanta Pokhrel

    2015-01-01

    Biodegradable polymers play a very important role in plastic engineering by replacing non biodegradable, non renewable petrol based polymers. Starch is a renewable, biodegradable, low cost natural polymer with high availability. Natural polymers can be blended with synthetic polymers to improve their properties significantly. This article reviews advance in starch and starch based blends and presents their numerous potential applications. Therefore, this review helps to understand the importa...

  13. Emerging optical techniques in advanced cystoscopy for bladder cancer diagnosis: A review of the current literature

    NARCIS (Netherlands)

    Cauberg Evelyne, C. C.; de La Rosette, Jean J. M. C. H.; de Reijke, Theo M.

    2011-01-01

    The current standard for the diagnosis and followup of bladder cancer remains white light cystoscopy, despite its well-known limitations. The aim of this paper is to review the current literature on three optical diagnostics that have been developed to improve the performance of white light

  14. Current advances and strategies towards fully automated sample preparation for regulated LC-MS/MS bioanalysis.

    Science.gov (United States)

    Zheng, Naiyu; Jiang, Hao; Zeng, Jianing

    2014-09-01

    Robotic liquid handlers (RLHs) have been widely used in automated sample preparation for liquid chromatography-tandem mass spectrometry (LC-MS/MS) bioanalysis. Automated sample preparation for regulated bioanalysis offers significantly higher assay efficiency, better data quality and potential bioanalytical cost-savings. For RLHs that are used for regulated bioanalysis, there are additional requirements, including 21 CFR Part 11 compliance, software validation, system qualification, calibration verification and proper maintenance. This article reviews recent advances in automated sample preparation for regulated bioanalysis in the last 5 years. Specifically, it covers the following aspects: regulated bioanalysis requirements, recent advances in automation hardware and software development, sample extraction workflow simplification, strategies towards fully automated sample extraction, and best practices in automated sample preparation for regulated bioanalysis.

  15. Advances in Instrumental Analysis of Brominated Flame Retardants: Current Status and Future Perspectives

    Science.gov (United States)

    2014-01-01

    This review aims to highlight the recent advances and methodological improvements in instrumental techniques applied for the analysis of different brominated flame retardants (BFRs). The literature search strategy was based on the recent analytical reviews published on BFRs. The main selection criteria involved the successful development and application of analytical methods for determination of the target compounds in various environmental matrices. Different factors affecting chromatographic separation and mass spectrometric detection of brominated analytes were evaluated and discussed. Techniques using advanced instrumentation to achieve outstanding results in quantification of different BFRs and their metabolites/degradation products were highlighted. Finally, research gaps in the field of BFR analysis were identified and recommendations for future research were proposed. PMID:27433482

  16. Key Advances in the Systemic Therapy for Soft tissue Sarcomas: Current Status and Future Directions

    Directory of Open Access Journals (Sweden)

    Neelesh Soman

    2013-10-01

    Full Text Available Soft tissue sarcomas (STS represent a heterogeneous group of diverse neoplasms of mesenchymal origin. Once relapsed from standard therapy, STS patients have limited treatment options especially those that present with advanced or metastatic disease. In this review article, we highlight recent clinical data that led to the US Food and Drug Administration (FDA approval of pazopanib (Votrient® for STS and regorafenib (Stivarga®, BAY 73-4506 in gastrointestinal stromal tumours. We also review ongoing safety/efficacy data for trabectedin (Yondelis®, ET-743, and data from clinical studies of ridaforolimus (AP23573; MK-8669 and palifosfamide (ZIO-201. We provide a list of some promising ongoing trials in soft tissue sarcomas including first line studies of TH-302 and trabectedin. Finally, our article delves into recent advances in our understanding of the molecular pathogenesis of STS and novel therapies that might be explored as treatment options for specific STS histologies.

  17. Biodegradable Sonobuoy Decelerators

    Science.gov (United States)

    2015-06-01

    agent. Samples were also analyzed for heavy metals which found concentrations below the toxicity threshold, ruling out metals contamination during...unlimited” 13. SUPPLEMENTARY NOTES 14. ABSTRACT In response to environmental concerns regarding nylon decelerators from sonobuoys polluting the oceans...readiness point for technology transition. 15. SUBJECT TERMS biodegrade, decelerator, sonobuoy, polyvinyl alcohol, polyhydroxyalkanoate, marine

  18. Biodegradable Materials for Nonwovens

    Science.gov (United States)

    Demand for nonwovens is increasing globally, particularly in the disposable products area. As the consumption of nonwoven products with short life increases, the burden on waste disposal also rises. In this context, biodegradable nonwovens become more important today and for the future. Several new ...

  19. Advances in regional anaesthesia: A review of current practice, newer techniques and outcomes

    Directory of Open Access Journals (Sweden)

    Christopher Wahal

    2018-01-01

    Full Text Available Advances in ultrasound guided regional anaesthesia and introduction of newer long acting local anaesthetics have given clinicians an opportunity to apply novel approaches to block peripheral nerves with ease. Consequently, improvements in outcomes such as quality of analgesia, early rehabilitation and patient satisfaction have been observed. In this article we will review some of the newer regional anaesthetic techniques, long acting local anaesthetics and adjuvants, and discuss evidence for key outcomes such as cancer recurrence and safety with ultrasound guidance.

  20. The importance of collaboration in the advancement of current and next generation reactors

    International Nuclear Information System (INIS)

    Jackson, Kate; Goossen, John; Anness, Mike; Meston, Tom

    2010-01-01

    The sections of the contribution are as follows: Tradition of innovation. Growing demand for nuclear power; Collaboration drivers; Responses. Knowledge transfer and management is critical. What kind of focus? Equipment reliability. Advanced repair, replacement and construction approaches. Materials. Plant safety margins. Spent fuel management. Examples of European collaboration. Zorita materials examination. Collaboration in the development of next generation reactors; Westinghouse R and D priorities; A look to the future. (P.A.)

  1. Poly(trimethylene carbonate)-based polymers engineered for biodegradable functional biomaterials.

    Science.gov (United States)

    Fukushima, K

    2016-01-01

    Aliphatic polycarbonates have drawn attention as biodegradable polymers that can be applied to a broad range of resorbable medical devices. In particular, poly(trimethylene carbonate) (PTMC), its copolymers, and its derivatives are currently studied due to their unique degradation characteristics that are different from those of aliphatic polyesters. Furthermore, their flexible and hydrophobic nature has driven the application of PTMC-based polymers to soft tissue regeneration and drug delivery. This review presents the diverse applications and functionalization strategies of PTMC-based materials in relation to recent advances in medical technologies and their subsequent needs in clinical settings.

  2. Social Media, Big Data, and Mental Health: Current Advances and Ethical Implications.

    Science.gov (United States)

    Conway, Mike; O'Connor, Daniel

    2016-06-01

    Mental health (including substance abuse) is the fifth greatest contributor to the global burden of disease, with an economic cost estimated to be US $2.5 trillion in 2010, and expected to double by 2030. Developing information systems to support and strengthen population-level mental health monitoring forms a core part of the World Health Organization's Comprehensive Action Plan 2013-2020. In this paper, we review recent work that utilizes social media "big data" in conjunction with associated technologies like natural language processing and machine learning to address pressing problems in population-level mental health surveillance and research, focusing both on technological advances and core ethical challenges.

  3. Advanced National Seismic System—Current status, development opportunities, and priorities for 2017–2027

    Science.gov (United States)

    ,

    2017-05-25

    SummaryEarthquakes pose a threat to the safety of over 143 million people living in the United States. Earthquake impacts can be significantly reduced if communities understand their risk and take proactive steps to mitigate that risk. The Advanced National Seismic System (ANSS) is a cooperative effort to collect and analyze seismic and geodetic data on earthquakes, issue timely and reliable notifications of their occurrence and impacts, and provide data for earthquake research and the hazard and risk assessments that are the foundation for creating an earthquakeresilient nation.

  4. Modelling marine sediment biogeochemistry: Current knowledge gaps, challenges, and some methodological advice for advancement

    DEFF Research Database (Denmark)

    Lessin, Gennadi; Artioli, Yuri; Almroth-Rosell, Elin

    2018-01-01

    -pronged approach for the advancement of benthic and benthic-pelagic modelling, essential for improved understanding, management and prediction of the marine environment. This includes: (A) Development of a traceable and hierarchical framework for benthic-pelagic models, which will facilitate integration among...... models, reduce risk of bias, and clarify model limitations; (B) extended cross-disciplinary approach to promote effective collaboration between modelling and empirical scientists of various backgrounds and better involvement of stakeholders and end-users; (C) a common vocabulary for terminology used...

  5. Current advances and challenges in microfluidic free-flow electrophoresis-A critical review.

    Science.gov (United States)

    Novo, Pedro; Janasek, Dirk

    2017-10-23

    The research field on microfluidic free-flow electrophoresis has developed vast amounts of devices, methods, applications and raised new questions, often in analogy to conventional techniques from which it derives. Most efforts have been employed on device development and a myriad of architectures and fabrication techniques have been reported using simple proof-of-principle separations. As technological aspects reach a quite mature state, researchers' new challenges include the development of protocols for the separation of complex mixtures, as required in the fields of application. The success of this effort is extremely dependent on the capability to transfer the device's fabrication to an industrial setting as well as to ensure interfacing simplicity, namely at the solutions' supply and collection, and actuation such as electric potential application and temperature control. Other advanced applications such as direct interfacing to downstream systems such as mass spectrometry, integration of sensing and feedback controls will require further development in the laboratory. In this review we provide an overview on the field, from basic concepts, through advanced developments both in the theoretical and experimental arenas, and addressing the above details. A comprehensive survey of designs, materials and applications is presented with particular highlights to most recent developments, namely the integration of electrodes, flow control and hyphenation of microfluidic free-flow electrophoresis with other techniques. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Advanced molecular diagnostic techniques for detection of food-borne pathogens: Current applications and future challenges.

    Science.gov (United States)

    Umesha, S; Manukumar, H M

    2018-01-02

    The elimination of disease-causing microbes from the food supply is a primary goal and this review deals with the overall techniques available for detection of food-borne pathogens. Now-a-days conventional methods are replaced by advanced methods like Biosensors, Nucleic Acid-based Tests (NAT), and different PCR-based techniques used in molecular biology to identify specific pathogens. Bacillus cereus, Staphylococcus aureus, Proteus vulgaris, Escherichia coli, Campylobacter, Listeria monocytogenes, Salmonella spp., Aspergillus spp., Fusarium spp., Penicillium spp., and pathogens are detected in contaminated food items that cause always diseases in human in any one or the other way. Identification of food-borne pathogens in a short period of time is still a challenge to the scientific field in general and food technology in particular. The low level of food contamination by major pathogens requires specific sensitive detection platforms and the present area of hot research looking forward to new nanomolecular techniques for nanomaterials, make them suitable for the development of assays with high sensitivity, response time, and portability. With the sound of these, we attempt to highlight a comprehensive overview about food-borne pathogen detection by rapid, sensitive, accurate, and cost affordable in situ analytical methods from conventional methods to recent molecular approaches for advanced food and microbiology research.

  7. The application of neural network for the advancement of the eddy current testing

    International Nuclear Information System (INIS)

    Sakai, T.; Soneda, N.

    1996-01-01

    All the steam generator (SG) tubes of Japanese pressurized water reactors (PWRs) are inspected by the eddy current testing (ECT) method in every annual scheduled inspection. Here, a neural network system to estimate the class and size of defects from signals obtained by the eddy current testing (ECT) method has been developed. A trajectory of ECT signal is characterized by four representative parameters, and totally eight parameters obtained from two trajectories by different AC current frequencies are used as input parameters for neutral networks. A probabilistic descent method is employed to minimize the error at the learning process of neural networks. It is indicated that using multiple neutral networks which are separately responsible to each class of defects is effective to the improvement of their estimation accuracy. And, it is demonstrated that the neural network system which the authors developed can estimate the class and size of defects from unlearned trajectories with high accuracy

  8. Summary and viewgraphs from the Q-121 US/Japan advanced current drive concepts workshop

    International Nuclear Information System (INIS)

    Bonoli, P.; Porkolab, M.; Chan, V.; Pinsker, R.; Politzer, P.; Darrow, D.; Fukuyama, Atsushi; Imai, Tsuyoshi; Watari, Tetsuo; Itoh, Satoshi; Nakamura, Yukio; James, R.; Logan, G.; Porter, G.; Thomassen, K.; Lyon, J.; Mau, Tak; Tanaka, Hitoshi; Tanaka, Shigetoshi

    1990-01-01

    With the emphasis placed on current drive by ITER, which requires steady state operation in its engineering phase, it is important to bring theory and experiment in agreement for each of the schemes that could be used in that design. Both neutral beam and lower hybrid (LH) schemes are in excellent shape in that regard. Since the projected efficiency of all schemes is marginal it is also important to continue our search for more efficient processes. This workshop featured experimental and theoretical work in each processes. This workshop featured experimental and theoretical work in each of these areas, that is, validation of theory and the search for better ideas. There were a number of notable results to report, the most striking again (as with last year) the long pulse operation of TRIAM-1M. A low current was sustained for over 1 hour with LH waves, using new hall-effect sensors in the equilibrium field circuit to maintain position control. In JT-60, by sharpening the wave spectrum the current drive efficiency was improved to 0.34 x 10 20 m -2 A/W and 1.5 MA of current was driven entirely by the lower hybrid system. Also in that machine, using two different LH frequencies, the H-mode was entered. Finally, by using the LH system for startup they saved 2.5 resistive volt-sec of flux, which if extrapolated to ITER would save 40 volt-sec there. For the first time, and experiment on ECH current drive showed reasonable agreement with theory. Those experiments are reported here by James (LLNL) on the D3-D machine. Substantially lower ECH current drive than expected theoretically was observed on WT-3, but if differed by being in a low absorption regime. Nonetheless, excellent physics results were achieved in the WT-3 experiments, notably in having careful measurements of the parallel velocity distributions

  9. Biodegradation of uranium-contaminated waste oil

    International Nuclear Information System (INIS)

    Hary, L.F.

    1983-01-01

    The Portsmouth Gaseous Diffusion Plant routinely generates quantities of uranium-contaminated waste oil. The current generation rate of waste oil is approximately 2000 gallons per year. The waste is presently biodegraded by landfarming on open field soil plots. However, due to the environmental concerns associated with this treatment process, studies were conducted to determine the optimum biodegradation conditions required for the destruction of this waste. Tests using respirometric flasks were conducted to determine the biodegradation rate for various types of Portsmouth waste oil. These tests were performed at three different loading rates, and on unfertilized and fertilized soil. Additional studies were conducted to evaluate the effectiveness of open field landfarming versus treatment at a greenhouse-like enclosure for the purpose of maintaining soil temperatures above ambient conditions. The respirometric tests concluded that the optimum waste oil loading rate is 10% weight of oil-carbon/weight of soil (30,600 gallons of uranium-contaminated waste oil/acre) on soils with adjusted carbon:nitrogen and carbon:phosphorus ratios of 60:1 and 800:1, respectively. Also, calculational results indicated that greenhouse technology does not provide a significant increase in biodegradation efficiency. Based on these study results, a 6300 ft. 2 abandoned anaerobic digester sludge drying bed is being modified into a permanent waste oil biodegradation facility. The advantage of using this area is that uranium contamination will be contained by the bed's existing leachate collection system. This modified facility will be capable of handling approximately 4500 gallons of waste oil per year; accordingly current waste generation quantities will be satisfactorily treated. 15 refs., 14 figs., 4 tabs

  10. Eddy Current, Magnetic Particle and Hardness Testing, Aviation Quality Control (Advanced): 9227.04.

    Science.gov (United States)

    Dade County Public Schools, Miami, FL.

    This unit of instruction includes the principles of eddy current, magnetic particle and hardness testing; standards used for analyzing test results; techniques of operating equipment; interpretation of indications; advantages and limitations of these methods of testing; care and calibration of equipment; and safety and work precautions. Motion…

  11. Chronopotentiometry for the advanced current-voltage characterisation of bipolar membranes

    NARCIS (Netherlands)

    Wilhelm, F.G.; van der Vegt, N.F.A.; Wessling, Matthias; Strathmann, H.

    2001-01-01

    Compared to steady-state current¿voltage curves, chronopotentiometric measurements allow us to distinguish the contributions to the overall electric potential difference across a bipolar membrane. In this paper, the characteristic values of the electric potential difference across the bipolar

  12. Advanced launcher design options for electron cyclotron current drive on ITER based on remote steering

    NARCIS (Netherlands)

    Graswinckel, M. R.; Bongers, W. A.; M.R. de Baar,; van den Berg, M. A.; Denisov, G.; Donne, A. J. H.; Elzendoorn, B. S. Q.; Goede, A. P. H.; Heidinger, R.; Kuzikov, S.; Kruijt, O. G.; Kruizinga, B.; Moro, A.; Poli, E.; Ronden, D. M. S.; Saibene, G.; Thoen, D. J.; Verhoeven, A. G. A.

    2008-01-01

    Electron cyclotron current drive will become the main scheme on ITER for the stabilization of neoclassical tearing modes (NTMs) and the control of sawtooth oscillations. The effectiveness of this scheme forms the basis for the requirements of the ITER Upper Port Launcher. These requirements include

  13. Methods for quantification of soil-transmitted helminths in environmental media: current techniques and recent advances

    Science.gov (United States)

    Collender, Philip A.; Kirby, Amy E.; Addiss, David G.; Freeman, Matthew C.; Remais, Justin V.

    2015-01-01

    Limiting the environmental transmission of soil-transmitted helminths (STH), which infect 1.5 billion people worldwide, will require sensitive, reliable, and cost effective methods to detect and quantify STH in the environment. We review the state of the art of STH quantification in soil, biosolids, water, produce, and vegetation with respect to four major methodological issues: environmental sampling; recovery of STH from environmental matrices; quantification of recovered STH; and viability assessment of STH ova. We conclude that methods for sampling and recovering STH require substantial advances to provide reliable measurements for STH control. Recent innovations in the use of automated image identification and developments in molecular genetic assays offer considerable promise for improving quantification and viability assessment. PMID:26440788

  14. Entanglement in continuous-variable systems: recent advances and current perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Adesso, Gerardo [Dipartimento di Fisica, Universita degli Studi di Roma ' La Sapienza' , Piazzale Aldo Moro 5, I-00185 Rome (Italy); Illuminati, Fabrizio [Dipartimento di Matematica e Informatica, Universita degli Studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano (Italy)

    2007-07-13

    We review the theory of continuous-variable entanglement with special emphasis on foundational aspects, conceptual structures and mathematical methods. Much attention is devoted to the discussion of separability criteria and entanglement properties of Gaussian states, for their great practical relevance in applications to quantum optics and quantum information, as well as for the very clean framework that they allow for the study of the structure of nonlocal correlations. We give a self-contained introduction to phase-space and symplectic methods in the study of Gaussian states of infinite-dimensional bosonic systems. We review the most important results on the separability and distillability of Gaussian states and discuss the main properties of bipartite entanglement. These include the extremal entanglement, minimal and maximal, of two-mode mixed Gaussian states, the ordering of two-mode Gaussian states according to different measures of entanglement, the unitary (reversible) localization and the scaling of bipartite entanglement in multimode Gaussian states. We then discuss recent advances in the understanding of entanglement sharing in multimode Gaussian states, including the proof of the monogamy inequality of distributed entanglement for all Gaussian states. Multipartite entanglement of Gaussian states is reviewed by discussing its qualification by different classes of separability, and the main consequences of the monogamy inequality, such as the quantification of genuine tripartite entanglement in three-mode Gaussian states, the promiscuous nature of entanglement sharing in symmetric Gaussian states and the possible coexistence of unlimited bipartite and multipartite entanglement. We finally review recent advances and discuss possible perspectives on the qualification and quantification of entanglement in non-Gaussian states, a field of research that is to a large extent yet to be explored.

  15. [Biodegradable catheters and urinary stents. When?

    Science.gov (United States)

    Soria, F; Morcillo, E; López de Alda, A; Pastor, T; Sánchez-Margallo, F M

    2016-10-01

    One of the main wishes in the field of urinary catheters and stents is to arm them with biodegradable characteristics because we consider a failure of these devices the need for retrieval, the forgotten catheter syndrome as well as the adverse effects permanent devices cause after fulfilling their aim. The efforts focused in new designs, coatings and biomaterials aim to increase the biocompatibility of theses internal devices. Lately, there have been correct advances to answer the main challenges regarding biodegradable ureteral devices. Thus, modulation of the rate of degradation has been achieved thanks to new biomaterials and the use of copolymers that enable to choose the time of permanence as it is programmed with conventional double J catheters. Biocompatibility has improved with the use of new polymers that adapt better to the urine. Finally, one of the main problems is elimination of degraded fragments and experimentally it has be demonstrated that new designs elicit controlled degradation, from distal to proximal; using stranding and combination of copolymers degradation may be caused by dilution, reducing fragmentation to the last stages of life of the prosthesis. Moreover, it has been demonstrated that biodegradable catheters potentially may cause less urinary tract infection, less encrustation and predictably they will diminish catheter morbidity, since their degradation process reduces adverse effects. Regarding the development of biodegradable urethral stents, it is necessary to find biomaterials that enable maintaining their biomechanical properties in the long term, keeping open the urethral lumen both in patients with BPH and urethral stenosis. Modulation of the time of degradation of the prosthesis has been achieved, but the appearance of urothelial hyperplasia is still a constant in the initial phases after implantation. The development of drug eluting stents, anti-proliferative or anti-inflammatory, as well as biodegradable stents biocoated is a

  16. Biodegradation of Cyanuric Acid

    Science.gov (United States)

    Saldick, Jerome

    1974-01-01

    Cyanuric acid biodegrades readily under a wide variety of natural conditions, and particularly well in systems of either low or zero dissolved-oxygen level, such as anaerobic activated sludge and sewage, soils, muds, and muddy streams and river waters, as well as ordinary aerated activated sludge systems with typically low (1 to 3 ppm) dissolved-oxygen levels. Degradation also proceeds in 3.5% sodium chloride solution. Consequently, there are degradation pathways widely available for breaking down cyanuric acid discharged in domestic effluents. The overall degradation reaction is merely a hydrolysis; CO2 and ammonia are the initial hydrolytic breakdown products. Since no net oxidation occurs during this breakdown, biodegradation of cyanuric acid exerts no primary biological oxygen demand. However, eventual nitrification of the ammonia released will exert its usual biological oxygen demand. PMID:4451360

  17. FED-A, an advanced performance FED based on low safety factor and current drive

    International Nuclear Information System (INIS)

    Peng, Y.K.M.; Rutherford, P.H.

    1983-08-01

    The FED-A study aims to quantify the potential improvement in cost-effectiveness of the Fusion Engineering Device (FED) by assuming low safety factor q (less than 2 as opposed to about 3) at the plasma edge and noninductive current drive (as opposed to only inductive current drive). The FED-A performance objectives are set to be : (1) ignition assuming International Tokamak Reactor (INTOR) plamsa confinement scaling, but still achieving a fusion power amplification Q greater than or equal to 5 when the confinement is degraded by a factor of 2; (2) neutron wall loading of about 1 MW/m 2 , with 0.5 MW/m 2 as a conservative lower bound; and (3) more clearly power-reactor-like operations, such as steady state

  18. Current role of non-anesthesiologist administered propofol sedation in advanced interventional endoscopy

    DEFF Research Database (Denmark)

    Burtea, Daniela Elena; Dimitriu, Anca; Maloş, Anca Elena

    2015-01-01

    the patients and medical personnel. Current guidelines support the use of propofol sedation, which has the same rate of adverse effects as traditional sedation with benzodiazepines and/or opioids, but decreases the procedural and recovery time. Non-anesthesiologist administered propofol sedation has become......, improved satisfaction for patients and doctors, as well as decreased recovery and discharge time. Despite the advantages of non-anesthesiologist administered propofol, there is still a continuous debate related to the successful generalization of the procedures....

  19. Anxiety and depression in patients with advanced macular degeneration: current perspectives

    Directory of Open Access Journals (Sweden)

    Cimarolli VR

    2015-12-01

    Full Text Available Verena R Cimarolli,1 Robin J Casten,2 Barry W Rovner,3–5 Vera Heyl,6 Silvia Sörensen,7,8 Amy Horowitz9 1Research Institute on Aging, Jewish Home Lifecare, New York, NY, USA; 2Department of Psychiatry and Human Behavior, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA, USA; 3Department of Neurology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA, USA; 4Department of Psychiatry, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA, USA; 5Department of Ophthalmology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA, USA; 6Institute of Special Education, University of Education, Heidelberg, Germany; 7Warner School of Education and Human Development, University of Rochester, Rochester, NY, USA; 8Department of Ophthalmology, Flaum Eye Institute, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA; 9Graduate School of Social Service, Fordham University, New York, NY, USA Abstract: Age-related macular degeneration (AMD – despite advances in prevention and medical treatment options – remains prevalent among older adults, often resulting in functional losses that negatively affect the mental health of older adults. In particular, the prevalence of both anxiety and depression in patients with AMD is high. Along with medical treatment options, low vision rehabilitation and AMD-specific behavioral and self-management programs have been developed and have demonstrated effectiveness in improving the mental health of AMD patients. This article reviews the prevalence of anxiety and depression in patients with advanced AMD, discusses potential mechanisms accounting for the development of depression and anxiety in AMD patients, presents the state-of the-art of available interventions for addressing anxiety and depression in AMD patients, and delineates recommendations for eye care professionals regarding how to

  20. Modeling Biodegradation of Nonylphenol

    International Nuclear Information System (INIS)

    Jahan, Kauser; Ordonez, Raul; Ramachandran, Ravi; Balzer, Shira; Stern, Michael

    2008-01-01

    Nonylphenol is the primary breakdown product of nonylphenol ethoxylates, a certain class of nonionic surfactants. Nonylphenol has been found to be toxic to aquatic organisms and has been suspected of being harmful to humans due to its xenoestrogenic properties. Although there are known releases of nonylphenol to the environment, there is a lack of data describing the extent of biodegradation. This study thus focuses on much needed information on the biodegradation kinetics of nonylphenol. Oxygen uptake, cell growth and nonylphenol removal data were collected using batch reactors in an electrolytic respirometer. Nonylphenol removal, cell growth and substrate removal rates were modeled by the Monod, Haldane, Aiba, Webb, and Yano equations. The differential equations were solved by numerical integration to simulate cell growth, substrate removal, and oxygen uptake as a function of time. All models provided similar results with the Haldane model providing the best fit. The values of the kinetic parameters and the activation energy for nonylphenol were determined. These values can be used for predicting fate and transport of nonylphenol in the environment. The validity of applying each model to the biodegradation of nonylphenol was analyzed by computing the R 2 values of each equation

  1. Treatment patterns of advanced malignant melanoma (stage III-IV) - A review of current standards in Europe.

    Science.gov (United States)

    Harries, Mark; Malvehy, Josep; Lebbe, Céleste; Heron, Louise; Amelio, Justyna; Szabo, Zsolt; Schadendorf, Dirk

    2016-06-01

    With the recent emergence of immunotherapies and novel targeted treatments for advanced and metastatic melanoma such as selective B-Raf inhibitors and checkpoint inhibitors, the treatment landscape in Europe has changed considerably. The aim of this review was to provide an overview of current treatment pathways in Europe for the treatment of advanced melanoma, unresectable stage III-IV. A literature search of four databases was conducted to identify publications reporting on the treatment patterns of advanced and metastatic melanoma (stage III-IV) in European populations. Seven full-text publications and two conference abstracts reported on observational studies of melanoma treatment practices in France, Italy and the United Kingdom. Treatment patterns were identified for two time periods: 2005-2009 and 2011-2012. Common treatments reported for both periods included chemotherapy with dacarbazine, fotemustine or temozolomide. The main differences between the two periods were the introduction and prescription of immunotherapy ipilimumab and targeted therapy vemurafenib between 2011 and 2012. Across the three countries studied, the types of treatments prescribed between 2005 and 2009 were relatively similar, however, with noticeable differences in the frequency and priority of administration. Treatment practices for advanced melanoma vary markedly across different European countries and continue to evolve with the introduction of new therapies. The results of this review highlight a considerable evidence gap with regards to recent treatment patterns for advanced melanoma in Europe, especially post-2011 after the introduction of novel therapeutic agents, and more recently with the introduction of programmed cell death 1 inhibitors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Genome and metabolic engineering in non-conventional yeasts: Current advances and applications

    Directory of Open Access Journals (Sweden)

    Ann-Kathrin Löbs

    2017-09-01

    Full Text Available Microbial production of chemicals and proteins from biomass-derived and waste sugar streams is a rapidly growing area of research and development. While the model yeast Saccharomyces cerevisiae is an excellent host for the conversion of glucose to ethanol, production of other chemicals from alternative substrates often requires extensive strain engineering. To avoid complex and intensive engineering of S. cerevisiae, other yeasts are often selected as hosts for bioprocessing based on their natural capacity to produce a desired product: for example, the efficient production and secretion of proteins, lipids, and primary metabolites that have value as commodity chemicals. Even when using yeasts with beneficial native phenotypes, metabolic engineering to increase yield, titer, and production rate is essential. The non-conventional yeasts Kluyveromyces lactis, K. marxianus, Scheffersomyces stipitis, Yarrowia lipolytica, Hansenula polymorpha and Pichia pastoris have been developed as eukaryotic hosts because of their desirable phenotypes, including thermotolerance, assimilation of diverse carbon sources, and high protein secretion. However, advanced metabolic engineering in these yeasts has been limited. This review outlines the challenges of using non-conventional yeasts for strain and pathway engineering, and discusses the developed solutions to these problems and the resulting applications in industrial biotechnology.

  3. Current advances in tissue repair and regeneration: the future is bright.

    Science.gov (United States)

    Ninov, Nikolay; Yun, Maximina H

    2015-04-01

    The fifth EMBO conference on 'The Molecular and Cellular Basis of Regeneration and Repair' took place in the peaceful coastal town of Sant Feliu de Guixols (Spain) on September 2014. The meeting was organised by Emili Saló (U. Barcelona, Spain), Kimberly Mace (U. Manchester, UK), Patrizia Ferretti (University College London, UK) and Michael Brand (Centre for Regenerative Therapies Dresden, Germany) and received the generous support of Society for Developmental Biology, The Company of Biologists, Centre for Regenerative Therapies Dresden, Garland Science and the journals Regeneration and Cell Signalling. The natural surroundings provided an inspiring setting for 185 researchers from all over the world to share their latest findings and views on the field. The conference showcased the great diversity of model organisms used for studying regeneration and tissue repair, including invertebrate and vertebrate species (Fig. 1). Importantly, this diversity in animal models allowed for a global overview of the mechanisms that promote regeneration. In addition, it highlighted some of the unique aspects that confer differences in regenerative capacities among different species. These differences might lie in each of the different steps involved in performing regeneration, including triggering the regenerative response, controlling cellular plasticity, re-stablishing the correct tissue patterns, as well as determining the roles of extrinsic factors, such as the role of inflammation in regeneration. A deeper understanding of these processes in the naturally regenerating species is a prerequisite for advancing the field of regenerative medicine and tissue repair in humans.

  4. Current status of decommissioning projects and their strategies in advanced countries

    Energy Technology Data Exchange (ETDEWEB)

    Chung, U. S.; Lee, K. W.; Hwang, D. S.; Park, S. K.; Hwang, S. T.; Paik, S. T.; Park, J. H.; Choi, Y. D.; Chung, K. H.; Lee, K. I.; Hong, S. B

    2007-06-15

    At the Korea Atomic Energy Research Institute(KAERI), two projects for decommissioning of the research reactors and uranium conversion plant are carried out. The number of nuclear facilities to be dismantled will be much increased in future and the decommissioning industries will be enlarged. Keeping pace with this increasing tendency, each country formulated their own strategies and regulation systems, and applied their own technologies. The international organizations such as the IAEA and the OECD/NEA also prepared standards in technologies and regulation upon decommissioning and recommended to adopt them to the decommissioning projects. These strategies and technologies are very different country by country due to the different site dependent conditions and it will not be reasonable to evaluate their merits and weakness. The world wide status of the decommissioning, highlighted on that of 5 countries of USA, UK, France, Germany and Japan because they are advanced counties in nuclear industries, are summarized and their site specific conditions are evaluated. The scopes of the evaluation are decommissioning strategies, licensing procedures and requirements focused on decommissioning plan, waste management, technology development and so on. The detailed decommissioning progresses of several typical example sites were introduced. The activities on decommissioning field of the international organization, increased according to the enlarged decommissioning industries, are also summarized.

  5. Current major advances in the regulation of milk protein gene expression.

    Science.gov (United States)

    Qian, Xi; Zhao, Feng-Qi

    2014-01-01

    During lactation, functionally differentiated mammary epithelial cells convert circulating nutrients into various milk components, providing all essential nutrients for the growth and development of mammal neonates. One of the major milk components is milk protein, which includes the casein and whey proteins. Regulation of milk protein gene expression is dependent on hormonal and developmental cues that modulate the activity of specific transcription factors and change the chromatin structure in mammary epithelial cells. Understanding the underlying mechanisms involved in mammary-specific milk protein gene regulation will help improve the yield, quality, and efficiency of milk production and identify important signaling factors and pathways involved in mammary development, differentiation, lactation, and disease. In this review we first review advances in the understanding of the regulatory mechanisms of milk protein genes by hormones, growth factors, and the extracellular matrix, with a focus on transcriptional regulation. We then discuss the relationship between chromatin structure and milk protein gene expression from an epigenetic perspective. Finally, we summarize recent achievements using the mammary gland as a bioreactor for producing pharmaceutical proteins for human use.

  6. CURRENT APPROACHES TO CONSERVATIVE AND COMBINED TREATMENT FOR LOCALLY ADVANCED LARYNGEAL CANCER

    Directory of Open Access Journals (Sweden)

    V. A. Pankratov

    2013-01-01

    Full Text Available The comparative analysis of results of conservative and combined treatment was carried out. The study group consisted of 400 patients with stage T3–4N0–3M0 laryngeal cancer who received concurrent chemotherapy and radiation therapy in combination with various physical radiomodifyers. The control group comprised 920 patients treated with the same technique but without systemic polychemotherapy. The 5-year relapse-free and overall survival rates were significantly higher in the study group than in the control group  (concervative treatment: 71 % and 86 % versus 37 % and 64.8 %, respectively, р<0,001 and combined treatment: 80 % and 83 % versus 47.4 % and 52 %, respectively(р<0,001. The functional organ was preserved in 71.2 % of locally advanced laryngeal cancer patients treated conservatively compared to 37.0 % of the control group patients. Oprgan-preserving surgeries were performed in 30.5% and 23%, respectively. The total number of patients with the larynx preservation was 50 % of the stydy group and 31.6 % of the control group.

  7. Evolution, current status and advances in application of platelet concentrate in periodontics and implantology.

    Science.gov (United States)

    Agrawal, Amit Arvind

    2017-05-16

    Platelet concentrates (PC) [platelet-rich plasma (PRP) and platelet-rich fibrin (PRF)] are frequently used for surgical procedures in medical and dental fields, particularly in oral and maxillofacial surgery, plastic surgery and sports medicine. The objective of all these technologies is to extract all the elements from a blood sample that could be used to improve healing and promote tissue regeneration. Although leukocyte rich and leukocyte poor PRP's have their own place in literature, the importance of non-platelet components in a platelet concentrate remains a mystery. PC have come a long way since its first appearance in 1954 to the T-PRF, A-PRF and i-PRF introduced recently. These PC find varied applications successfully in periodontics and implant dentistry as well. However, the technique of preparation, standing time, transfer process, temperature of centrifuge, vibration, etc ., are the various factors for the mixed results reported in the literature. Until the introduction of a proper classification of terminologies, the PC were known by different names in different countries and by different commercial companies which also created a lot of confusion. This review intends to clarify all these confusion by briefing the exact evolution of PC, their preparation techniques, recent advances and their various clinical and technical aspects and applications.

  8. Synthetic biology and molecular genetics in non-conventional yeasts: Current tools and future advances.

    Science.gov (United States)

    Wagner, James M; Alper, Hal S

    2016-04-01

    Coupling the tools of synthetic biology with traditional molecular genetic techniques can enable the rapid prototyping and optimization of yeast strains. While the era of yeast synthetic biology began in the well-characterized model organism Saccharomyces cerevisiae, it is swiftly expanding to include non-conventional yeast production systems such as Hansenula polymorpha, Kluyveromyces lactis, Pichia pastoris, and Yarrowia lipolytica. These yeasts already have roles in the manufacture of vaccines, therapeutic proteins, food additives, and biorenewable chemicals, but recent synthetic biology advances have the potential to greatly expand and diversify their impact on biotechnology. In this review, we summarize the development of synthetic biological tools (including promoters and terminators) and enabling molecular genetics approaches that have been applied in these four promising alternative biomanufacturing platforms. An emphasis is placed on synthetic parts and genome editing tools. Finally, we discuss examples of synthetic tools developed in other organisms that can be adapted or optimized for these hosts in the near future. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Comparative investigation of the economics of seawater desalting based on current and advanced distillation concepts

    International Nuclear Information System (INIS)

    Glueckstern, P.; Reed, S.A.

    1976-01-01

    A reassessment of desalting plant design and product water cost based on current technology and energy and equipment costs has been made. Plant sizes in the range of 1 to 200 Mgd utilizing the multistage flash (MSF) and the vertical tube evaporator (VTE) were investigated. Process steam was assumed to be supplied by large nuclear dual-purpose plants or from fossil-fired low-pressure boilers. Plants applying the pH control method versus the threshold pretreatment method were compared. The potential benefits of applying low cost aluminum tubing in low-temperature VTE plants were also investigated

  10. Biodegradable packaging materials : case: PLA

    OpenAIRE

    Jama, Mohamed

    2017-01-01

    The main aim of this bachelor thesis was to investigate the possibility of biodegradable packaging materials. Plastics and other non-degradable packaging materials have been used for many years and they have a negative impact on the environment since they do not degrade. Different research methods are used to get authentic results, which simplifies using biodegradable packaging materials. There were two biodegradability testing methods, which has been applied to this task:-, testing biode...

  11. Comparison of the long-term skeletal stability between a biodegradable and a titanium fixation system following BSSO advancement - A cohort study based on a multicenter randomised controlled trial

    NARCIS (Netherlands)

    van Bakelen, N. B.; Boermans, B. D. A.; Buijs, G. J.; Jansma, J.; Pruim, G. J.; Hoppenreijs, Th. J. M.; Bergsma, J. E.; Stegenga, B.; Bos, R. R. M.

    2014-01-01

    Biodegradable fixation systems could reduce or eliminate the problems associated with removal of titanium plates. A multicenter randomised controlled trial (RCT) was performed in the Netherlands from December 2006-July 2009, and originally 230 injured and orthognathic patients were included. The

  12. Extrapolating power-ramp performance criteria for current and advanced CANDU fuels

    International Nuclear Information System (INIS)

    Tayal, M.; Chassie, G.G.

    2000-06-01

    To improve the precision and accuracy of power-ramp performance criteria for high-burnup fuel, we have examined in-reactor fuel performance data as well as out-reactor test data. The data are consistent with some of the concepts used in the current formulations for defining fuel failure thresholds, such as size of power-ramp and extent of burnup. Our review indicates that there is a need to modify some other aspects of the current formulations; therefore, a modified formulation is presented in this paper. The improvements mainly concern corrodent concentration and its relationships with threshold stress for failure. The new formulation is consistent with known and expected trends such as strength of Zircaloy in corrosive environment, timing of the release of fission products to the pellet-to-sheath gap, CANLUB coating, and fuel burnup. Because of the increased precision and accuracy, the new formulation is better able to identify operational regimes that are at risk of power-ramp failures; this predictive ability provides enhanced protection to fuel against power-ramp defects. At die same time, by removing unnecessary conservatisms in other areas, the new formulation permits a greater range of defect-free operational envelope as well as larger operating margins in regions that are, in fact, not prone to power-ramp failures. (author)

  13. Recent advances in high current vacuum arc ion sources for heavy ion fusion

    CERN Document Server

    Qi Nian Sheng; Prasad, R R; Krishnan, M S; Anders, A; Kwan, J; Brown, I

    2001-01-01

    For a heavy ion fusion induction linac driver, a source of heavy ions with charge states 1+-3+, approx 0.5 A current beams, approx 20 mu s pulse widths and approx 10 Hz repetition rates is required. Thermionic sources have been the workhorse for the Heavy Ion Fusion (HIF) program to date, but suffer from heating problems for large areas and contamination. They are limited to low (contact) ionization potential elements and offer relatively low ion fluxes with a charge state limited to 1+. Gas injection sources suffer from partial ionization and deleterious neutral gas effects. The above shortcomings of the thermionic ion sources can be overcome by a vacuum arc ion source. The vacuum arc ion source is a good candidate for HIF applications. It is capable of providing ions of various elements and different charge states in short and long pulse bursts and high beam current density. Under a Phase-I STTR from DOE, the feasibility of the vacuum arc ion source for the HIF applications was investigated. We have modifie...

  14. ADVANCED SIMULATION CAPABILITY FOR ENVIRONMENTAL MANAGEMENT – CURRENT STATUS AND PHASE II DEMONSTRATION RESULTS

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, Roger; Freshley, Mark D.; Dixon, Paul; Hubbard, Susan S.; Freedman, Vicky L.; Flach, Gregory P.; Faybishenko, Boris; Gorton, Ian; Finsterle, Stefan A.; Moulton, John D.; Steefel, Carl I.; Marble, Justin

    2013-06-27

    The U.S. Department of Energy (USDOE) Office of Environmental Management (EM), Office of Soil and Groundwater, is supporting development of the Advanced Simulation Capability for Environmental Management (ASCEM). ASCEM is a state-of-the-art scientific tool and approach for understanding and predicting contaminant fate and transport in natural and engineered systems. The modular and open source high-performance computing tool facilitates integrated approaches to modeling and site characterization that enable robust and standardized assessments of performance and risk for EM cleanup and closure activities. The ASCEM project continues to make significant progress in development of computer software capabilities with an emphasis on integration of capabilities in FY12. Capability development is occurring for both the Platform and Integrated Toolsets and High-Performance Computing (HPC) Multiprocess Simulator. The Platform capabilities provide the user interface and tools for end-to-end model development, starting with definition of the conceptual model, management of data for model input, model calibration and uncertainty analysis, and processing of model output, including visualization. The HPC capabilities target increased functionality of process model representations, toolsets for interaction with Platform, and verification and model confidence testing. The Platform and HPC capabilities are being tested and evaluated for EM applications in a set of demonstrations as part of Site Applications Thrust Area activities. The Phase I demonstration focusing on individual capabilities of the initial toolsets was completed in 2010. The Phase II demonstration completed in 2012 focused on showcasing integrated ASCEM capabilities. For Phase II, the Hanford Site deep vadose zone (BC Cribs) served as an application site for an end-to-end demonstration of capabilities, with emphasis on integration and linkages between the Platform and HPC components. Other demonstrations

  15. Current Advances in L-DOPA and DOPA-Peptidomimetics: Chemistry, Applications and Biological Activity.

    Science.gov (United States)

    Bizzarri, Bruno Mattia; Tortolini, Silvia; Rotelli, Luca; Botta, Giorgia; Saladino, Raffaele

    2015-01-01

    L-3,4-Dihydroxyphenylalanine [2-amino-3-(3,4-dihydroxyphenyl) propanoic acid (L-DOPA) is a natural constituent of animal and plant tissue derived from post-translational modification of the amino acid tyrosine. L-DOPA is modified during metabolism to catecholamine neurotransmitters, noradrenaline and adrenaline, which are characterized by different biological activities. L-DOPA has been the first drug of choice in the therapy of Parkinson's disease that is a progressive neurodegenerative disorder involving the loss of dopaminergic neurons of substantia nigra pars compacta. The social and economic impact of these diseases is very high due to the progressive aging of the population. This review focuses on the biological effect of LDOPA, as well as on the synthesis of L-DOPA derivatives and their application in central nervous system diseases. Among them, L-DOPA-containing peptides (L-DOPA-Pep) show important biological and pharmacological activities. For example, L-DOPA analogues of the alpha-factor interact with models of the G protein-coupled receptor, inhibit the oxidation of low-density lipoproteins, and are used for improving L-DOPA absorption in long-term treatment of Parkinson's disease and as skin moisturizer in cosmetic compositions. Moreover, L-DOPA residues in proteins provide reactive tools for the preparation of adhesives and coatings materials. Usually, L-DOPA-Pep is prepared by traditional liquid or solid state procedures starting from simple amino acids. Recently, selective side-chain modifications of pre-formed peptides have also been reported both for linear and branched peptides. Here, we describe the recent advances in the synthesis of L-DOPA and dopa-peptidomimetics and their biological and pharmacological activities, focusing the attention on new synthetic procedures and biological mechanism of actions.

  16. Effect of Wave Accessibility on Lower Hybrid Wave Current Drive in Experimental Advanced Superconductor Tokamak with H-Mode Operation

    International Nuclear Information System (INIS)

    Li Xin-Xia; Xiang Nong; Gan Chun-Yun

    2015-01-01

    The effect of the wave accessibility condition on the lower hybrid current drive in the experimental advanced superconductor Tokamak (EAST) plasma with H-mode operation is studied. Based on a simplified model, a mode conversion layer of the lower hybrid wave between the fast wave branch and the slow wave branch is proved to exist in the plasma periphery for typical EAST H-mode parameters. Under the framework of the lower hybrid wave simulation code (LSC), the wave ray trajectory and the associated current drive are calculated numerically. The results show that the wave accessibility condition plays an important role on the lower hybrid current drive in EAST plasma. For wave rays with parallel refractive index n ‖ = 2.1 or n ‖ = 2.5 launched from the outside midplane, the wave rays may penetrate the core plasma due to the toroidal geometry effect, while numerous reflections of the wave ray trajectories in the plasma periphery occur. However, low current drive efficiency is obtained. Meanwhile, the wave accessibility condition is improved if a higher confined magnetic field is applied. The simulation results show that for plasma parameters under present EAST H-mode operation, a significant lower hybrid wave current drive could be obtained for the wave spectrum with peak value n ‖ = 2.1 if a toroidal magnetic field B T = 2.5 T is applied. (paper)

  17. Advanced Simulation Capability for Environmental Management - Current Status and Phase II Demonstration Results - 13161

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, Roger R.; Flach, Greg [Savannah River National Laboratory, Savannah River Site, Bldg 773-43A, Aiken, SC 29808 (United States); Freshley, Mark D.; Freedman, Vicky; Gorton, Ian [Pacific Northwest National Laboratory, MSIN K9-33, P.O. Box 999, Richland, WA 99352 (United States); Dixon, Paul; Moulton, J. David [Los Alamos National Laboratory, MS B284, P.O. Box 1663, Los Alamos, NM 87544 (United States); Hubbard, Susan S.; Faybishenko, Boris; Steefel, Carl I.; Finsterle, Stefan [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 50B-4230, Berkeley, CA 94720 (United States); Marble, Justin [Department of Energy, 19901 Germantown Road, Germantown, MD 20874-1290 (United States)

    2013-07-01

    The U.S. Department of Energy (US DOE) Office of Environmental Management (EM), Office of Soil and Groundwater, is supporting development of the Advanced Simulation Capability for Environmental Management (ASCEM). ASCEM is a state-of-the-art scientific tool and approach for understanding and predicting contaminant fate and transport in natural and engineered systems. The modular and open source high-performance computing tool facilitates integrated approaches to modeling and site characterization that enable robust and standardized assessments of performance and risk for EM cleanup and closure activities. The ASCEM project continues to make significant progress in development of computer software capabilities with an emphasis on integration of capabilities in FY12. Capability development is occurring for both the Platform and Integrated Tool-sets and High-Performance Computing (HPC) Multi-process Simulator. The Platform capabilities provide the user interface and tools for end-to-end model development, starting with definition of the conceptual model, management of data for model input, model calibration and uncertainty analysis, and processing of model output, including visualization. The HPC capabilities target increased functionality of process model representations, tool-sets for interaction with Platform, and verification and model confidence testing. The Platform and HPC capabilities are being tested and evaluated for EM applications in a set of demonstrations as part of Site Applications Thrust Area activities. The Phase I demonstration focusing on individual capabilities of the initial tool-sets was completed in 2010. The Phase II demonstration completed in 2012 focused on showcasing integrated ASCEM capabilities. For Phase II, the Hanford Site deep vadose zone (BC Cribs) served as an application site for an end-to-end demonstration of capabilities, with emphasis on integration and linkages between the Platform and HPC components. Other demonstrations

  18. Advanced Simulation Capability for Environmental Management - Current Status and Phase II Demonstration Results - 13161

    International Nuclear Information System (INIS)

    Seitz, Roger R.; Flach, Greg; Freshley, Mark D.; Freedman, Vicky; Gorton, Ian; Dixon, Paul; Moulton, J. David; Hubbard, Susan S.; Faybishenko, Boris; Steefel, Carl I.; Finsterle, Stefan; Marble, Justin

    2013-01-01

    The U.S. Department of Energy (US DOE) Office of Environmental Management (EM), Office of Soil and Groundwater, is supporting development of the Advanced Simulation Capability for Environmental Management (ASCEM). ASCEM is a state-of-the-art scientific tool and approach for understanding and predicting contaminant fate and transport in natural and engineered systems. The modular and open source high-performance computing tool facilitates integrated approaches to modeling and site characterization that enable robust and standardized assessments of performance and risk for EM cleanup and closure activities. The ASCEM project continues to make significant progress in development of computer software capabilities with an emphasis on integration of capabilities in FY12. Capability development is occurring for both the Platform and Integrated Tool-sets and High-Performance Computing (HPC) Multi-process Simulator. The Platform capabilities provide the user interface and tools for end-to-end model development, starting with definition of the conceptual model, management of data for model input, model calibration and uncertainty analysis, and processing of model output, including visualization. The HPC capabilities target increased functionality of process model representations, tool-sets for interaction with Platform, and verification and model confidence testing. The Platform and HPC capabilities are being tested and evaluated for EM applications in a set of demonstrations as part of Site Applications Thrust Area activities. The Phase I demonstration focusing on individual capabilities of the initial tool-sets was completed in 2010. The Phase II demonstration completed in 2012 focused on showcasing integrated ASCEM capabilities. For Phase II, the Hanford Site deep vadose zone (BC Cribs) served as an application site for an end-to-end demonstration of capabilities, with emphasis on integration and linkages between the Platform and HPC components. Other demonstrations

  19. Comparison of advanced optical imaging techniques with current otolaryngology diagnostics for improved middle ear assessment (Conference Presentation)

    Science.gov (United States)

    Nolan, Ryan M.; Shelton, Ryan L.; Monroy, Guillermo L.; Spillman, Darold R.; Novak, Michael A.; Boppart, Stephen A.

    2016-02-01

    Otolaryngologists utilize a variety of diagnostic techniques to assess middle ear health. Tympanometry, audiometry, and otoacoustic emissions examine the mobility of the tympanic membrane (eardrum) and ossicles using ear canal pressure and auditory tone delivery and detection. Laser Doppler vibrometry provides non-contact vibrational measurement, and acoustic reflectometry is used to assess middle ear effusion using sonar. These technologies and techniques have advanced the field beyond the use of the standard otoscope, a simple tissue magnifier, yet the need for direct visualization of middle ear disease for superior detection, assessment, and management remains. In this study, we evaluated the use of portable optical coherence tomography (OCT) and pneumatic low-coherence interferometry (LCI) systems with handheld probe delivery to standard tympanometry, audiometry, otoacoustic emissions, laser Doppler vibrometry, and acoustic reflectometry. Comparison of these advanced optical imaging techniques and current diagnostics was conducted with a case study subject with a history of unilateral eardrum trauma. OCT and pneumatic LCI provide novel dynamic spatiotemporal structural data of the middle ear, such as the thickness of the eardrum and quantitative detection of underlying disease pathology, which could allow for more accurate diagnosis and more appropriate management than currently possible.

  20. Advances and Current Concepts in the Medical Management of Gastroenteropancreatic Neuroendocrine Neoplasms

    Directory of Open Access Journals (Sweden)

    Krystallenia I. Alexandraki

    2017-01-01

    Full Text Available Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs are rare and heterogeneous group of tumors presenting as localised or metastatic disease and in a subset with distinct clinical syndromes. Treatment is aimed at controlling the functional syndrome, eradicating the tumor, and/or preventing further tumor growth. Surgery is the treatment of choice in removing the primary tumor and/or reducing tumor burden but cannot be applied to all patients. Somatostatin analogs (SS-analogs obtain control of functional syndromes in the majority of GEP-neuroendocrine tumors (NETs; phase III trials have shown that SS-analogs can be used as first-line antiproliferative treatment in patients with slow-growing GEP-NETs. The role of the recently approved serotonin inhibitor, telotristat ethyl, and gastrin receptor antagonist, netazepide, is evolving. Streptozotocin-based chemotherapy has been used for inoperable or progressing pancreatic NENs but the orally administered combination of capecitabine/temozolomide is becoming more popular due to its better tolerability and potential effect in other GEP-NENs. Phase III trials have shown efficacy of molecular targeted therapies in GEP-NETs and of radionuclide treatment in patients with midgut carcinoid tumors expressing somatostatin receptors. Most patients will develop disease progression necessitating further therapeutic options. A combination of currently available treatments along with the molecular signature of each tumor will guide future treatment.

  1. Immunotherapy for Patients with Advanced Urothelial Cancer: Current Evidence and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Clizia Zichi

    2017-01-01

    Full Text Available In recent years, immunotherapy has produced encouraging results in a rapidly increasing number of solid tumors. The responsiveness of bladder cancer to immunotherapy was first established in nonmuscle invasive disease in 1976 with intravesical instillations of bacillus Calmette-Guérin (BCG. Very recently immune checkpoint inhibitors demonstrated good activity and significant efficacy in metastatic disease. In particular the best results were obtained with programmed death-ligand-1 (PD-L1 and programmed death-1 (PD-1 inhibitors, but many other immune checkpoint inhibitors, including anti-cytotoxic T-lymphocyte-associated protein-4 (CTLA-4 antibodies, are currently under investigation in several trials. Simultaneously other therapeutic strategies which recruit an adaptive immune response against tumoral antigens or employ externally manipulated tumor infiltrating lymphocytes might change the natural history of bladder cancer in the near future. This review describes the rationale for the use of immunotherapy in bladder cancer and discusses recent and ongoing clinical trials with checkpoint inhibitors and other novel immunotherapy agents.

  2. The role of germ cell loss during primordial follicle assembly: a review of current advances.

    Science.gov (United States)

    Sun, Yuan-Chao; Sun, Xiao-Feng; Dyce, Paul W; Shen, Wei; Chen, Hong

    2017-01-01

    In most female mammals, early germline development begins with the appearance of primordial germ cells (PGCs), and develops to form mature oocytes following several vital processes. It remains well accepted that significant germ cell apoptosis and oocyte loss takes place around the time of birth. The transition of the ovarian environment from fetal to neonatal, coincides with the loss of germ cells and the timing of follicle formation. All told it is common to lose approximately two thirds of germ cells during this transition period. The current consensus is that germ cell loss can be attributed, at least in part, to programmed cell death (PCD). Recently, autophagy has been implicated as playing a part in germ cell loss during the time of parturition. In this review, we discuss the major opinions and mechanisms of mammalian ovarian PCD during the process of germ cell loss. We also pay close attention to the function of autophagy in germ cell loss, and speculate that autophagy may also serve as a critical and necessary process during the establishment of primordial follicle pool.

  3. Current and advanced NO/sub x/-control technology for coal-fired industrial boilers

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-01

    A NOx-control-technology assessment study of coal-fired industrial boilers was conducted to examine the effectiveness of combustion-modification methods, including low excess air, staged combustion, and burner modifications. Boiler types considered included overfed and underfed stokers, spreader stokers, pulverized-coal and coal-fired cyclone units. Significant variations in NOx emissions occur with boiler type, firing method, and coal type; a relative comparison of emission-control performance, cost, and operational considerations is presented for each method. Baseline (as-found) emissions from grate-fired stokers were shown to be in the range of 200 to 300 ppM. Similarly, as-found emissions from suspension-fired units were quite low (350 to 600 ppM) as compared to comparably designed utility-sized units. Low excess air was shown to be the most effective method on existing units, reducing emissions by approximately 10%. Evaluation of staged combustion and burner modification, however, were limited due to current boiler designs. Major hardware modification/design and implementation are necessary before the potential of these techniques can be fully evaluated. The study emphasized the numerous operational factors that are of major importance to the user in selecting and implementing a combustion-modification program, including energy considerations, incremental capital and operating costs, corrosion, secondary pollutants, and retrofit potential.

  4. Diagnostic of corrosion defects in steam generator tubes using advanced signal processing from Eddy current testing

    International Nuclear Information System (INIS)

    Formigoni, Andre L.; Lopez, Luiz A.N.M.; Ting, Daniel K.S.

    2009-01-01

    Recently, the Brazilian Angra I PWR nuclear power plant went into a programmed shutdown for substitution of its Steam Generator (SG) which life was shortened due to stress corrosion in its tubes. The total cost of investment were around R$724 million. The signals generated during an Eddy-current Testing (ECT) inspection in SG tubes of nuclear plant allows for the localization and dimensioning of defects in the tubes. The defects related with corrosion generate complex signals that are difficult to analyze and are the most common cause in SG replacement in nuclear power plants around the world. The objective of this paper is the development of a methodology that allows for the characterization of corrosion signals by ECT inspections applied in the heat exchangers tubes of SG of a nuclear power plant. In this present work, the aim is to investigate distributed type defects by inducing controlled corrosion in sample tubes of different materials The ECT signals obtained from these samples tubes with corrosion implanted, will be analyzed using Zetec ECT equipment, the MIZ-17ET and its probes. The data acquisition will use a NI PC A/D CARD 700 card and the LabVIEW program. Subsequently, we will apply mathematical tools for signal processing like time windowed Fast Fourier transforms and Wavelets transforms, in MATLAB platform, which will allow effectiveness to remove the noises and to extract representative characteristics for the defect being analyzed. Previously obtained results as well as the proposal for the future work will be presented. (author)

  5. Current advances in mathematical modeling of anti-cancer drug penetration into tumor tissues.

    Science.gov (United States)

    Kim, Munju; Gillies, Robert J; Rejniak, Katarzyna A

    2013-11-18

    Delivery of anti-cancer drugs to tumor tissues, including their interstitial transport and cellular uptake, is a complex process involving various biochemical, mechanical, and biophysical factors. Mathematical modeling provides a means through which to understand this complexity better, as well as to examine interactions between contributing components in a systematic way via computational simulations and quantitative analyses. In this review, we present the current state of mathematical modeling approaches that address phenomena related to drug delivery. We describe how various types of models were used to predict spatio-temporal distributions of drugs within the tumor tissue, to simulate different ways to overcome barriers to drug transport, or to optimize treatment schedules. Finally, we discuss how integration of mathematical modeling with experimental or clinical data can provide better tools to understand the drug delivery process, in particular to examine the specific tissue- or compound-related factors that limit drug penetration through tumors. Such tools will be important in designing new chemotherapy targets and optimal treatment strategies, as well as in developing non-invasive diagnosis to monitor treatment response and detect tumor recurrence.

  6. Current advances in biomarkers for targeted therapy in triple-negative breast cancer

    Directory of Open Access Journals (Sweden)

    Fleisher B

    2016-10-01

    Full Text Available Brett Fleisher,1 Charlotte Clarke,2 Sihem Ait-Oudhia1 1Department of Pharmaceutics, Center for Pharmacometrics and Systems Pharmacology, College of Pharmacy, University of Florida, Orlando, FL, 2Department of Translational Research, UT MD Anderson Cancer Center, Houston, TX, USA Abstract: Triple-negative breast cancer (TNBC is a complex heterogeneous disease characterized by the absence of three hallmark receptors: human epidermal growth factor receptor 2, estrogen receptor, and progesterone receptor. Compared to other breast cancer subtypes, TNBC is more aggressive, has a higher prevalence in African-Americans, and more frequently affects younger patients. Currently, TNBC lacks clinically accepted targets for tailored therapy, warranting the need for candidate biomarkers. BiomarkerBase, an online platform used to find biomarkers reported in clinical trials, was utilized to screen all potential biomarkers for TNBC and select only the ones registered in completed TNBC trials through clinicaltrials.gov. The selected candidate biomarkers were classified as surrogate, prognostic, predictive, or pharmacodynamic (PD and organized by location in the blood, on the cell surface, in the cytoplasm, or in the nucleus. Blood biomarkers include vascular endothelial growth factor/vascular endothelial growth factor receptor and interleukin-8 (IL-­8; cell surface biomarkers include EGFR, insulin-like growth factor binding protein, c-Kit, c-Met, and PD-L1; cytoplasm biomarkers include PIK3CA, pAKT/S6/p4E-BP1, PTEN, ALDH1, and the PIK3CA/AKT/mTOR-related metabolites; and nucleus biomarkers include BRCA1, the glucocorticoid receptor, TP53, and Ki67. Candidate biomarkers were further organized into a “cellular protein network” that demonstrates potential connectivity. This review provides an inventory and reference point for promising biomarkers for breakthrough targeted therapies in TNBC. Keywords: anti-cancer directed pharmacotherapy, difficult

  7. The Development of Perioperative Practices for Liver Transplantation: Advances and Current Trends

    Directory of Open Access Journals (Sweden)

    Merceds Susan Mandell

    2008-09-01

    Full Text Available Transplantation is a young medical specialty that has grown rapidly over the past 50 years. Anesthesiologists, surgeons and hepatologists are all essential partners in the process of determining patient outcome. Each specialty has made landmark improvements in patient outcome. However, there is still variability in practice patterns in each of the 3 major specialties. This review will use a historic perspective to explore the unique forces that shaped specific transplant practices and those that gave rise to differences in perioperative practices. Anesthesiologists and surgeons have made significant improvements in the management of blood loss, and coagulation monitoring and intervention. This has improved operative survival and early patient outcome. Perioperative survival has improved despite a worldwide shortage of donor organs and a trend to transplant sicker patients. A smaller pool of donor organs is required to meet the needs of an expanding waiting list. The innovations to reduce deaths on the transplant wait list are reviewed along with their impact on overall patient outcome. The evolving organ shortage is the pinnacle point in shaping future transplant practices. Currently, institutional-specific practices may be reinforced by the informal “tutorship” that is used to train physicians and by the resources available at each site of practice. However, there is evidence that specific intraoperative practices such as the use of a low central venous pressure, selection of vasopressors and certain surgical techniques can modify patient outcome. Further investigation is needed to determine whether the good or the bad associated with each practice prevails and in what unique circumstance.

  8. Advanced ceramic matrix composite materials for current and future propulsion technology applications

    Science.gov (United States)

    Schmidt, S.; Beyer, S.; Knabe, H.; Immich, H.; Meistring, R.; Gessler, A.

    2004-08-01

    Current rocket engines, due to their method of construction, the materials used and the extreme loads to which they are subjected, feature a limited number of load cycles. Various technology programmes in Europe are concerned, besides developing reliable and rugged, low cost, throwaway equipment, with preparing for future reusable propulsion technologies. One of the key roles for realizing reusable engine components is the use of modern and innovative materials. One of the key technologies which concern various engine manufacturers worldwide is the development of fibre-reinforced ceramics—ceramic matrix composites. The advantages for the developers are obvious—the low specific weight, the high specific strength over a large temperature range, and their great damage tolerance compared to monolithic ceramics make this material class extremely interesting as a construction material. Over the past years, the Astrium company (formerly DASA) has, together with various partners, worked intensively on developing components for hypersonic engines and liquid rocket propulsion systems. In the year 2000, various hot-firing tests with subscale (scale 1:5) and full-scale nozzle extensions were conducted. In this year, a further decisive milestone was achieved in the sector of small thrusters, and long-term tests served to demonstrate the extraordinary stability of the C/SiC material. Besides developing and testing radiation-cooled nozzle components and small-thruster combustion chambers, Astrium worked on the preliminary development of actively cooled structures for future reusable propulsion systems. In order to get one step nearer to this objective, the development of a new fibre composite was commenced within the framework of a regionally sponsored programme. The objective here is to create multidirectional (3D) textile structures combined with a cost-effective infiltration process. Besides material and process development, the project also encompasses the development of

  9. Calcium orthophosphate coatings on magnesium and its biodegradable alloys.

    Science.gov (United States)

    Dorozhkin, Sergey V

    2014-07-01

    Biodegradable metals have been suggested as revolutionary biomaterials for bone-grafting therapies. Of these metals, magnesium (Mg) and its biodegradable alloys appear to be particularly attractive candidates due to their non-toxicity and as their mechanical properties match those of bones better than other metals do. Being light, biocompatible and biodegradable, Mg-based metallic implants have several advantages over other implantable metals currently in use, such as eliminating both the effects of stress shielding and the requirement of a second surgery for implant removal. Unfortunately, the fast degradation rates of Mg and its biodegradable alloys in the aggressive physiological environment impose limitations on their clinical applications. This necessitates development of implants with controlled degradation rates to match the kinetics of bone healing. Application of protective but biocompatible and biodegradable coatings able to delay the onset of Mg corrosion appears to be a reasonable solution. Since calcium orthophosphates are well tolerated by living organisms, they appear to be the excellent candidates for such coatings. Nevertheless, both the high chemical reactivity and the low melting point of Mg require specific parameters for successful deposition of calcium orthophosphate coatings. This review provides an overview of current coating techniques used for deposition of calcium orthophosphates on Mg and its biodegradable alloys. The literature analysis revealed that in all cases the calcium orthophosphate protective coatings both increased the corrosion resistance of Mg-based metallic biomaterials and improved their surface biocompatibility. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  10. Biodegradable Piezoelectric Force Sensor.

    Science.gov (United States)

    Curry, Eli J; Ke, Kai; Chorsi, Meysam T; Wrobel, Kinga S; Miller, Albert N; Patel, Avi; Kim, Insoo; Feng, Jianlin; Yue, Lixia; Wu, Qian; Kuo, Chia-Ling; Lo, Kevin W-H; Laurencin, Cato T; Ilies, Horea; Purohit, Prashant K; Nguyen, Thanh D

    2018-01-30

    Measuring vital physiological pressures is important for monitoring health status, preventing the buildup of dangerous internal forces in impaired organs, and enabling novel approaches of using mechanical stimulation for tissue regeneration. Pressure sensors are often required to be implanted and directly integrated with native soft biological systems. Therefore, the devices should be flexible and at the same time biodegradable to avoid invasive removal surgery that can damage directly interfaced tissues. Despite recent achievements in degradable electronic devices, there is still a tremendous need to develop a force sensor which only relies on safe medical materials and requires no complex fabrication process to provide accurate information on important biophysiological forces. Here, we present a strategy for material processing, electromechanical analysis, device fabrication, and assessment of a piezoelectric Poly-l-lactide (PLLA) polymer to create a biodegradable, biocompatible piezoelectric force sensor, which only employs medical materials used commonly in Food and Drug Administration-approved implants, for the monitoring of biological forces. We show the sensor can precisely measure pressures in a wide range of 0-18 kPa and sustain a reliable performance for a period of 4 d in an aqueous environment. We also demonstrate this PLLA piezoelectric sensor can be implanted inside the abdominal cavity of a mouse to monitor the pressure of diaphragmatic contraction. This piezoelectric sensor offers an appealing alternative to present biodegradable electronic devices for the monitoring of intraorgan pressures. The sensor can be integrated with tissues and organs, forming self-sensing bionic systems to enable many exciting applications in regenerative medicine, drug delivery, and medical devices.

  11. Past, Current and Future of the Advanced Microwave Scanning Radiometer (AMSR) Series

    Science.gov (United States)

    Kachi, M.; Maeda, T.; Ono, N.; Tomii, N.; Kasahara, M.; Mokuno, M.; Sobue, S.

    2017-12-01

    time and quality, transition from AMSR-2 to follow-on mission to continue operational applications and keep long-term data record for climate studies. Currently, JAXA is studying possible payload capability of AMSR-2 follow-on onto the Greenhouse Gases Observation Satellite-3 (GOSAT-3) scheduled to be launched in Japanese Fiscal Year 2022.

  12. PREPARATION AND CHARACTERIZATION OF BIODEGRADABLE ...

    African Journals Online (AJOL)

    Dr Abdusalam

    Keywords: Starch, Acetylation, Biodegradation, Poly(vinyl alcohol), Polymer blend. INTRODUCTION. Non-biodegradable polymers, such as polyethene, polypropane, poly(vinylchloride) etc have excellent mechanical properties such as tensile strength, tensile strain, bursting strength and tear strength (Hay and. Sharma.

  13. Thermodynamic Analysis of Biodegradation Pathways

    Science.gov (United States)

    Finley, Stacey D.; Broadbelt, Linda J.

    2014-01-01

    Microorganisms provide a wealth of biodegradative potential in the reduction and elimination of xenobiotic compounds in the environment. One useful metric to evaluate potential biodegradation pathways is thermodynamic feasibility. However, experimental data for the thermodynamic properties of xenobiotics is scarce. The present work uses a group contribution method to study the thermodynamic properties of the University of Minnesota Biocatalysis/Biodegradation Database. The Gibbs free energies of formation and reaction are estimated for 914 compounds (81%) and 902 reactions (75%), respectively, in the database. The reactions are classified based on the minimum and maximum Gibbs free energy values, which accounts for uncertainty in the free energy estimates and a feasible concentration range relevant to biodegradation. Using the free energy estimates, the cumulative free energy change of 89 biodegradation pathways (51%) in the database could be estimated. A comparison of the likelihood of the biotransformation rules in the Pathway Prediction System and their thermodynamic feasibility was then carried out. This analysis revealed that when evaluating the feasibility of biodegradation pathways, it is important to consider the thermodynamic topology of the reactions in the context of the complete pathway. Group contribution is shown to be a viable tool for estimating, a priori, the thermodynamic feasibility and the relative likelihood of alternative biodegradation reactions. This work offers a useful tool to a broad range of researchers interested in estimating the feasibility of the reactions in existing or novel biodegradation pathways. PMID:19288443

  14. Syntrophic biodegradation of hydrocarbon contaminants.

    Science.gov (United States)

    Gieg, Lisa M; Fowler, S Jane; Berdugo-Clavijo, Carolina

    2014-06-01

    Anaerobic environments are crucial to global carbon cycling wherein the microbial metabolism of organic matter occurs under a variety of redox conditions. In many anaerobic ecosystems, syntrophy plays a key role wherein microbial species must cooperate, essentially as a single catalytic unit, to metabolize substrates in a mutually beneficial manner. Hydrocarbon-contaminated environments such as groundwater aquifers are typically anaerobic, and often methanogenic. Syntrophic processes are needed to biodegrade hydrocarbons to methane, and recent studies suggest that syntrophic hydrocarbon metabolism can also occur in the presence of electron acceptors. The elucidation of key features of syntrophic processes in defined co-cultures has benefited greatly from advances in 'omics' based tools. Such tools, along with approaches like stable isotope probing, are now being used to monitor carbon flow within an increasing number of hydrocarbon-degrading consortia to pinpoint the key microbial players involved in the degradative pathways. The metagenomic sequencing of hydrocarbon-utilizing consortia should help to further identify key syntrophic features and define microbial interactions in these complex communities. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Application of a Biodegradable Lubricant in a Diesel Vehicle

    DEFF Research Database (Denmark)

    Schramm, Jesper

    2003-01-01

    The IEA Advanced Motor Fuels Agreement has initiated this project concerning the application of biodegradable lubricants to diesel and gasoline type vehicles. Emission measurements on a chassis dynamometer were carried out. The purpose of these measurements was to compare the emissions of CO, CO2......, NOx, THC, PM, lubricant-SOF and PAH from one diesel and one gasoline type vehicle using biodegradable lubricants and conventional lubricants. This paper describes the results of the experiments with the diesel type vehicle only. Lubricant consumption and fuel consumption are other important parameters...

  16. Degradation of 5-FU by means of advanced (photo)oxidation processes: UV/H{sub 2}O{sub 2}, UV/Fe{sup 2+}/H{sub 2}O{sub 2} and UV/TiO{sub 2} — Comparison of transformation products, ready biodegradability and toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Lutterbeck, Carlos Alexandre, E-mail: lutterbeck@leuphana.de [Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainability, Leuphana University of Lüneburg, Scharnhorststraße 1/C13, DE-21335 Lüneburg (Germany); Graduate Program in Environmental Technology, Universidade de Santa Cruz do Sul — UNISC, Av. Independência, 2293, CEP 96815-900 Santa Cruz do Sul, Rio Grande do Sul (Brazil); Wilde, Marcelo Luís, E-mail: wilde@leuphana.de [Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainability, Leuphana University of Lüneburg, Scharnhorststraße 1/C13, DE-21335 Lüneburg (Germany); Baginska, Ewelina, E-mail: ewelina.baginska@leuphana.de [Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainability, Leuphana University of Lüneburg, Scharnhorststraße 1/C13, DE-21335 Lüneburg (Germany); Leder, Christoph, E-mail: cleder@leuphana.de [Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Faculty of Sustainability, Leuphana University of Lüneburg, Scharnhorststraße 1/C13, DE-21335 Lüneburg (Germany); Machado, Ênio Leandro, E-mail: enio@unisc.br [Graduate Program in Environmental Technology, Universidade de Santa Cruz do Sul — UNISC, Av. Independência, 2293, CEP 96815-900 Santa Cruz do Sul, Rio Grande do Sul (Brazil); and others

    2015-09-15

    The present study investigates the degradation of the antimetabolite 5-fluorouracil (5-FU) by three different advanced photo oxidation processes: UV/H{sub 2}O{sub 2}, UV/Fe{sup 2+}/H{sub 2}O{sub 2} and UV/TiO{sub 2}. Prescreening experiments varying the H{sub 2}O{sub 2} and TiO{sub 2} concentrations were performed in order to set the best catalyst concentrations in the UV/H{sub 2}O{sub 2} and UV/TiO{sub 2} experiments, whereas the UV/Fe{sup 2+}/H{sub 2}O{sub 2} process was optimized varying the pH, Fe{sup 2+} and H{sub 2}O{sub 2} concentrations by means of the Box–Behnken design (BBD). 5-FU was quickly removed in all the irradiation experiments. The UV/Fe{sup 2+}/H{sub 2}O{sub 2} and UV/TiO{sub 2} processes achieved the highest degree of mineralization, whereas the lowest one resulted from the UV/H{sub 2}O{sub 2} treatment. Six transformation products were formed during the advanced (photo)oxidation processes and identified using low and high resolution mass spectrometry. Most of them were formed and further eliminated during the reactions. The parent compound of 5-FU was not biodegraded, whereas the photolytic mixture formed in the UV/H{sub 2}O{sub 2} treatment after 256 min showed a noticeable improvement of the biodegradability in the closed bottle test (CBT) and was nontoxic towards Vibrio fischeri. In silico predictions showed positive alerts for mutagenic and genotoxic effects of 5-FU. In contrast, several of the transformation products (TPs) generated along the processes did not provide indications for mutagenic or genotoxic activity. One exception was TP with m/z 146 with positive alerts in several models of bacterial mutagenicity which could demand further experimental testing. Results demonstrate that advanced treatment can eliminate parent compounds and its toxicity. However, transformation products formed can still be toxic. Therefore toxicity screening after advanced treatment is recommendable. - Highlights: • Full primary elimination of 5-FU was

  17. Modeling Nitrogen Losses in Conventional and Advanced Soil-Based Onsite Wastewater Treatment Systems under Current and Changing Climate Conditions.

    Science.gov (United States)

    Morales, Ivan; Cooper, Jennifer; Amador, José A; Boving, Thomas B

    2016-01-01

    Most of the non-point source nitrogen (N) load in rural areas is attributed to onsite wastewater treatment systems (OWTS). Nitrogen compounds cause eutrophication, depleting the oxygen in marine ecosystems. OWTS rely on physical, chemical and biological soil processes to treat wastewater and these processes may be affected by climate change. We simulated the fate and transport of N in different types of OWTS drainfields, or soil treatment areas (STA) under current and changing climate scenarios, using 2D/3D HYDRUS software. Experimental data from a mesocosm-scale study, including soil moisture content, and total N, ammonium (NH4+) and nitrate (NO3-) concentrations, were used to calibrate the model. A water content-dependent function was used to compute the nitrification and denitrification rates. Three types of drainfields were simulated: (1) a pipe-and-stone (P&S), (2) advanced soil drainfields, pressurized shallow narrow drainfield (PSND) and (3) Geomat (GEO), a variation of SND. The model was calibrated with acceptable goodness-of-fit between the observed and measured values. Average root mean square error (RSME) ranged from 0.18 and 2.88 mg L-1 for NH4+ and 4.45 mg L-1 to 9.65 mg L-1 for NO3- in all drainfield types. The calibrated model was used to estimate N fluxes for both conventional and advanced STAs under current and changing climate conditions, i.e. increased soil temperature and higher water table. The model computed N losses from nitrification and denitrification differed little from measured losses in all STAs. The modeled N losses occurred mostly as NO3- in water outputs, accounting for more than 82% of N inputs in all drainfields. Losses as N2 were estimated to be 10.4% and 9.7% of total N input concentration for SND and Geo, respectively. The highest N2 losses, 17.6%, were estimated for P&S. Losses as N2 increased to 22%, 37% and 21% under changing climate conditions for Geo, PSND and P&S, respectively. These findings can provide practitioners

  18. Advanced practice registered nurses and physician assistants in sleep centers and clinics: a survey of current roles and educational background.

    Science.gov (United States)

    Colvin, Loretta; Cartwright, Ann; Collop, Nancy; Freedman, Neil; McLeod, Don; Weaver, Terri E; Rogers, Ann E

    2014-05-15

    To survey Advanced Practice Registered Nurse (APRN) and Physician Assistant (PA) utilization, roles and educational background within the field of sleep medicine. Electronic surveys distributed to American Academy of Sleep Medicine (AASM) member centers and APRNs and PAs working within sleep centers and clinics. Approximately 40% of responding AASM sleep centers reported utilizing APRNs or PAs in predominantly clinical roles. Of the APRNs and PAs surveyed, 95% reported responsibilities in sleep disordered breathing and more than 50% in insomnia and movement disorders. Most APRNs and PAs were prepared at the graduate level (89%), with sleep-specific education primarily through "on the job" training (86%). All APRNs surveyed were Nurse Practitioners (NPs), with approximately double the number of NPs compared to PAs. APRNs and PAs were reported in sleep centers at proportions similar to national estimates of NPs and PAs in physicians' offices. They report predominantly clinical roles, involving common sleep disorders. Given current predictions that the outpatient healthcare structure will change and the number of APRNs and PAs will increase, understanding the role and utilization of these professionals is necessary to plan for the future care of patients with sleep disorders. Surveyed APRNs and PAs reported a significant deficiency in formal and standardized sleep-specific education. Efforts to provide formal and standardized educational opportunities for APRNs and PAs that focus on their clinical roles within sleep centers could help fill a current educational gap.

  19. Incremental Innovation and Progress in Advanced Squamous Cell Lung Cancer: Current Status and Future Impact of Treatment.

    Science.gov (United States)

    Langer, Corey J; Obasaju, Coleman; Bunn, Paul; Bonomi, Philip; Gandara, David; Hirsch, Fred R; Kim, Edward S; Natale, Ronald B; Novello, Silvia; Paz-Ares, Luis; Pérol, Maurice; Reck, Martin; Ramalingam, Suresh S; Reynolds, Craig H; Socinski, Mark A; Spigel, David R; Wakelee, Heather; Mayo, Carlos; Thatcher, Nick

    2016-12-01

    Squamous cell lung cancer (sqCLC) is an aggressive form of cancer that poses many therapeutic challenges. Patients tend to be older, present at a later stage, and have a high incidence of comorbidities, which can compromise treatment delivery and exacerbate toxicity. In addition, certain agents routinely available for nonsquamous cell histologic subtypes, such as bevacizumab and pemetrexed, are contraindicated or lack efficacy in sqCLC. Therapeutic progress has been much slower for advanced sqCLC, with median survival times of approximately 9 to 11 months in most studies. Herein, we discuss the current therapeutic landscape for patients with sqCLC versus with nonsquamous NSCLC. Current evidence indicates that new targeted treatments, notably monoclonal antibodies such as ramucirumab and necitumumab, and immunotherapies such as nivolumab and pembrolizumab can provide survival prolongation, although the benefits are still relatively modest. These incremental improvements, all realized since 2012, in aggregate, will very likely have a clinically meaningful impact for patients with sqCLC. We also discuss recent genomic studies of sqCLC that have identified potentially actionable molecular targets, as well as the relevant targeted agents in clinical development. Finally, we discuss the magnitude of survival benefit and the risk-to-benefit ratio that would prove clinically meaningful in this underserved patient population with unmet needs. Copyright © 2016 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

  20. Biodegradable Magnesium Implants — How do They Corrode in-Vivo?

    Science.gov (United States)

    Witte, Frank; Hort, Norbert; Feyerabend, Frank

    Biodegradable magnesium implants are currently breaking the paradigm of designing and producing only corrosion resistant metallic biomaterials. The academic and industrial interest in this novel class of biomaterials is increasing dramatically in the recent years. First biodegradable metal implants have been realized as vascular stents and bone screws. However, the knowledge of the underlying degradation mechanism of these metal implants remains mainly undiscovered.

  1. Study on lower hybrid current drive efficiency at high density towards long-pulse regimes in Experimental Advanced Superconducting Tokamak

    International Nuclear Information System (INIS)

    Li, M. H.; Ding, B. J.; Zhang, J. Z.; Gan, K. F.; Wang, H. Q.; Zhang, L.; Wei, W.; Li, Y. C.; Wu, Z. G.; Ma, W. D.; Jia, H.; Chen, M.; Yang, Y.; Feng, J. Q.; Wang, M.; Xu, H. D.; Shan, J. F.; Liu, F. K.; Peysson, Y.

    2014-01-01

    Significant progress on both L- and H-mode long-pulse discharges has been made recently in Experimental Advanced Superconducting Tokamak (EAST) with lower hybrid current drive (LHCD) [J. Li et al., Nature Phys. 9, 817 (2013) And B. N. Wan et al., Nucl. Fusion 53, 104006 (2013).]. In this paper, LHCD experiments at high density in L-mode plasmas have been investigated in order to explore possible methods of improving current drive (CD) efficiency, thus to extend the operational space in long-pulse and high performance plasma regime. It is observed that the normalized bremsstrahlung emission falls much more steeply than 1/n e-av (line-averaged density) above n e-av  = 2.2 × 10 19  m −3 indicating anomalous loss of CD efficiency. A large broadening of the operating line frequency (f = 2.45 GHz), measured by a radio frequency (RF) probe located outside the EAST vacuum vessel, is generally observed during high density cases, which is found to be one of the physical mechanisms resulting in the unfavorable CD efficiency. Collisional absorption of lower hybrid wave in the scrape off layer (SOL) may be another cause, but this assertion needs more experimental evidence and numerical analysis. It is found that plasmas with strong lithiation can improve CD efficiency largely, which should be benefited from the changes of edge parameters. In addition, several possible methods are proposed to recover good efficiency in future experiments for EAST

  2. COMETS2: An advanced MATLAB toolbox for the numerical analysis of electric fields generated by transcranial direct current stimulation.

    Science.gov (United States)

    Lee, Chany; Jung, Young-Jin; Lee, Sang Jun; Im, Chang-Hwan

    2017-02-01

    Since there is no way to measure electric current generated by transcranial direct current stimulation (tDCS) inside the human head through in vivo experiments, numerical analysis based on the finite element method has been widely used to estimate the electric field inside the head. In 2013, we released a MATLAB toolbox named COMETS, which has been used by a number of groups and has helped researchers to gain insight into the electric field distribution during stimulation. The aim of this study was to develop an advanced MATLAB toolbox, named COMETS2, for the numerical analysis of the electric field generated by tDCS. COMETS2 can generate any sizes of rectangular pad electrodes on any positions on the scalp surface. To reduce the large computational burden when repeatedly testing multiple electrode locations and sizes, a new technique to decompose the global stiffness matrix was proposed. As examples of potential applications, we observed the effects of sizes and displacements of electrodes on the results of electric field analysis. The proposed mesh decomposition method significantly enhanced the overall computational efficiency. We implemented an automatic electrode modeler for the first time, and proposed a new technique to enhance the computational efficiency. In this paper, an efficient toolbox for tDCS analysis is introduced (freely available at http://www.cometstool.com). It is expected that COMETS2 will be a useful toolbox for researchers who want to benefit from the numerical analysis of electric fields generated by tDCS. Copyright © 2016. Published by Elsevier B.V.

  3. The temporary and accumulated effects of transcranial direct current stimulation for the treatment of advanced Parkinson’s disease monkeys

    Science.gov (United States)

    Li, Hao; Lei, Xiaoguang; Yan, Ting; Li, Hongwei; Huang, Baihui; Li, Ling; Xu, Liqi; Liu, Li; Chen, Nanhui; Lü, Longbao; Ma, Yuanye; Xu, Lin; Li, Jiali; Wang, Zhengbo; Zhang, Baorong; Hu, Xintian

    2015-01-01

    Transcranial direct current stimulation (tDCS) is a useful noninvasive technique of cortical brain stimulation for the treatment of neurological disorders. Clinical research has demonstrated tDCS with anodal stimulation of primary motor cortex (M1) in Parkinson’s disease (PD) patients significantly improved their motor function. However, few studies have been focused on the optimization of parameters which contributed significantly to the treatment effects of tDCS and exploration of the underline neuronal mechanisms. Here, we used different stimulation parameters of anodal tDCS on M1 for the treatment of aged advanced PD monkeys induced with 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) administration, and then analyzed the temporary and accumulated effects of tDCS treatment. The results indicated anodal tDCS on M1 very significantly improved motor ability temporarily; importantly, the treatment effects of anodal tDCS on M1 were quantitatively correlated to the accumulated stimulation instead of the stimuli intensity or duration respectively. In addition, c-fos staining showed tDCS treatment effects activated the neurons both in M1 and substantia nigra (SN). Therefore, we propose that long time and continue anodal tDCS on M1 is a better strategy to improve the motor symptoms of PD than individual manipulation of stimuli intensity or duration. PMID:26220760

  4. Innate and adaptive immunity in the development of depression: An update on current knowledge and technological advances

    Science.gov (United States)

    Haapakoski, Rita; Ebmeier, Klaus P.; Alenius, Harri; Kivimäki, Mika

    2016-01-01

    The inflammation theory of depression, proposed over 20 years ago, was influenced by early studies on T cell responses and since then has been a stimulus for numerous research projects aimed at understanding the relationship between immune function and depression. Observational studies have shown that indicators of immunity, especially C reactive protein and proinflammatory cytokines, such as interleukin 6, are associated with an increased risk of depressive disorders, although the evidence from randomized trials remains limited and only few studies have assessed the interplay between innate and adaptive immunity in depression. In this paper, we review current knowledge on the interactions between central and peripheral innate and adaptive immune molecules and the potential role of immune-related activation of microglia, inflammasomes and indoleamine-2,3-dioxygenase in the development of depressive symptoms. We highlight how combining basic immune methods with more advanced ‘omics’ technologies would help us to make progress in unravelling the complex associations between altered immune function and depressive disorders, in the identification of depression-specific biomarkers and in developing immunotherapeutic treatment strategies that take individual variability into account. PMID:26631274

  5. Progress of biodegradable metals

    Directory of Open Access Journals (Sweden)

    Huafang Li

    2014-10-01

    Full Text Available Biodegradable metals (BMs are metals and alloys expected to corrode gradually in vivo, with an appropriate host response elicited by released corrosion products, then dissolve completely upon fulfilling the mission to assist with tissue healing with no implant residues. In the present review article, three classes of BMs have been systematically reviewed, including Mg-based, Fe-based and Zn-based BMs. Among the three BM systems, Mg-based BMs, which now have several systems reported the successful of clinical trial results, are considered the vanguards and main force. Fe-based BMs, with pure iron and Fe–Mn based alloys as the most promising, are still on the animal test stage. Zn-based BMs, supposed to have the degradation rate between the fast Mg-based BMs and the slow Fe-based BMs, are a rising star with only several reports and need much further research. The future research and development direction for the BMs are proposed, based on the clinical requirements on controllable degradation rate, prolonged mechanical stability and excellent biocompatibility, by optimization of alloy composition design, regulation on microstructure and mechanical properties, and following surface modification.

  6. Treatment of biodegradable material

    Energy Technology Data Exchange (ETDEWEB)

    Pannell, S.D.; Greenshields, R.N.

    1981-05-13

    Biodegradable effluents, e.g. containing carbohydrates and/or proteins, were treated by passing up a tower fermenter tapered at the top and with an aspect ratio of greater than or equal to 3:1. A flocculant microorganism aerobically digested the effluent in the tower and the mixture of treated medium, gas, and surplus microorganism was discharged through an inverted-U-shaped outlet at the top. After separation of the biomass, which could be used as an animal feed, the purified effluent could be discharged. A milk-processing effluent (2.5 g solids/l, of which 65% was sucrose and 35% milk solids) was treated in a fermentation tower (aspect ratio 10:1). Aspergillus niger in the tower readily digested sucrose and at least some lactose as air and NH/sub 4/NO/sub 3/ were added. At least 90% of the casein was trapped by the microorganisms and discharged with them from the tower. The microrganisms were separated with a vibrating sieve giving a final discharged liquid containing 0.2 g solids/l.

  7. Advanced Manufacturing Systems in Food Processing and Packaging Industry

    International Nuclear Information System (INIS)

    Sani, Mohd Shafie; Aziz, Faieza Abdul

    2013-01-01

    In this paper, several advanced manufacturing systems in food processing and packaging industry are reviewed, including: biodegradable smart packaging and Nano composites, advanced automation control system consists of fieldbus technology, distributed control system and food safety inspection features. The main purpose of current technology in food processing and packaging industry is discussed due to major concern on efficiency of the plant process, productivity, quality, as well as safety. These application were chosen because they are robust, flexible, reconfigurable, preserve the quality of the food, and efficient.

  8. Characterisation and biodegradation of settleable organic matter for ...

    African Journals Online (AJOL)

    Biodegradation of settled COD is studied by evaluating the associated OUR profile obtained in an aerated batch reactor. Hydrolysis was selected, as in current modelling, as the rate-limiting step for O2 consumption. Settled COD was found to incorporate a significant fraction of active biomass that needs to be accounted for ...

  9. Size-controlled synthesis of biodegradable nanocarriers for targeted ...

    Indian Academy of Sciences (India)

    Abstract. Research for synthesis of size-controlled carriers is currently challenging one. In this research paper, a method for size-controlled synthesis of biodegradable nanocarriers is proposed and described. Salting out method is suitable for both hydrophilic and hydrophobic drugs for the encapsulation on carriers.

  10. Biodegradability and Microbial Toxicity of Aircraft Fuel System Icing Inhibitors

    National Research Council Canada - National Science Library

    Meshako, Charles

    1996-01-01

    ...%. These concentrations raise concerns as to the disposal and handling of these wastes. The current FSII, DiEGME was evaluated along with two new candidates, dipropylene glycol and glycerol formal DiEGME appeared to be moderately but not completely biodegradable...

  11. Size-controlled synthesis of biodegradable nanocarriers for targeted ...

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... Research for synthesis of size-controlled carriers is currently challenging one. In this research paper, a method for size-controlled synthesis of biodegradable nanocarriers is proposed and described. Salting out method is suitable for both hydrophilic and hydrophobic drugs for the encapsulation on carriers.

  12. A biodegradable rubber by crosslinking poly(hydroxyalkanoate) from Pseudomonas oleovorans

    NARCIS (Netherlands)

    DEKONING, GJM; VANBILSEN, HMM; LEMSTRA, PJ; HAZENBERG, W; Witholt, B.; Preusting, H.; VANDERGALIEN, JG; SCHIRMER, A; JENDROSSEK, D

    1994-01-01

    Poly((R)-3-hydroxyalkanoate)s (PHAs) are bacterial storage polyesters, currently receiving much attention because of their potential application as biodegradable and biocompatible plastics. Among them are the PHAs from Pseudomonas oleovorans, which are semicrystalline elastomers. Their applicability

  13. Biodegradable Peptide-Silica Nanodonuts.

    Science.gov (United States)

    Maggini, Laura; Travaglini, Leana; Cabrera, Ingrid; Castro-Hartmann, Pablo; De Cola, Luisa

    2016-03-07

    We report hybrid organosilica toroidal particles containing a short peptide sequence as the organic component of the hybrid systems. Once internalised in cancer cells, the presence of the peptide allows for interaction with peptidase enzymes, which attack the nanocarrier effectively triggering its structural breakdown. Moreover, these biodegradable nanovectors are characterised by high cellular uptake and exocytosis, showing great potential as biodegradable drug carriers. To demonstrate this feature, doxorubicin was employed and its delivery in HeLa cells investigated. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Arthroscopic Biodegradable Balloon

    African Journals Online (AJOL)

    2016-09-03

    Sep 3, 2016 ... components of the rotator cuff and deltoid muscle),. Original Article. Introduction. Massive irreparable rotator cuff ruptures characterized with retracted rotator cuffup to glenoid level, advanced stage fatty atrophy, narrowed acromiohumeral distance, and decreased excursion of tendon despite adequate ...

  15. Development of aliphatic biodegradable photoluminescent polymers.

    Science.gov (United States)

    Yang, Jian; Zhang, Yi; Gautam, Santosh; Liu, Li; Dey, Jagannath; Chen, Wei; Mason, Ralph P; Serrano, Carlos A; Schug, Kevin A; Tang, Liping

    2009-06-23

    None of the current biodegradable polymers can function as both implant materials and fluorescent imaging probes. The objective of this study was to develop aliphatic biodegradable photoluminescent polymers (BPLPs) and their associated cross-linked variants (CBPLPs) for biomedical applications. BPLPs are degradable oligomers synthesized from biocompatible monomers including citric acid, aliphatic diols, and various amino acids via a convenient and cost-effective polycondensation reaction. BPLPs can be further cross-linked into elastomeric cross-linked polymers, CBPLPs. We have shown representatively that BPLP-cysteine (BPLP-Cys) and BPLP-serine (BPLP-Ser) offer advantages over the traditional fluorescent organic dyes and quantum dots because of their preliminarily demonstrated cytocompatibility in vitro, minimal chronic inflammatory responses in vivo, controlled degradability and high quantum yields (up to 62.33%), tunable fluorescence emission (up to 725 nm), and photostability. The tensile strength of CBPLP-Cys film ranged from 3.25 +/- 0.13 MPa to 6.5 +/- 0.8 MPa and the initial Modulus was in a range of 3.34 +/- 0.15 MPa to 7.02 +/- 1.40 MPa. Elastic CBPLP-Cys could be elongated up to 240 +/- 36%. The compressive modulus of BPLP-Cys (0.6) (1:1:0.6 OD:CA:Cys) porous scaffold was 39.60 +/- 5.90 KPa confirming the soft nature of the scaffolds. BPLPs also possess great processability for micro/nano-fabrication. We demonstrate the feasibility of using BPLP-Ser nanoparticles ("biodegradable quantum dots") for in vitro cellular labeling and noninvasive in vivo imaging of tissue engineering scaffolds. The development of BPLPs and CBPLPs represents a new direction in developing fluorescent biomaterials and could impact tissue engineering, drug delivery, bioimaging.

  16. The effect of mechanical loads on the degradation of aliphatic biodegradable polyesters.

    Science.gov (United States)

    Li, Ying; Chu, Zhaowei; Li, Xiaoming; Ding, Xili; Guo, Meng; Zhao, Haoran; Yao, Jie; Wang, Lizhen; Cai, Qiang; Fan, Yubo

    2017-06-01

    Aliphatic biodegradable polyesters have been the most widely used synthetic polymers for developing biodegradable devices as alternatives for the currently used permanent medical devices. The performances during biodegradation process play crucial roles for final realization of their functions. Because physiological and biochemical environment in vivo significantly affects biodegradation process, large numbers of studies on effects of mechanical loads on the degradation of aliphatic biodegradable polyesters have been launched during last decades. In this review article, we discussed the mechanism of biodegradation and several different mechanical loads that have been reported to affect the biodegradation process. Other physiological and biochemical factors related to mechanical loads were also discussed. The mechanical load could change the conformational strain energy and morphology to weaken the stability of the polymer. Besides, the load and pattern could accelerate the loss of intrinsic mechanical properties of polymers. This indicated that investigations into effects of mechanical loads on the degradation should be indispensable. More combination condition of mechanical loads and multiple factors should be considered in order to keep the degradation rate controllable and evaluate the degradation process in vivo accurately. Only then can the degradable devise achieve the desired effects and further expand the special applications of aliphatic biodegradable polyesters.

  17. ANAEROBIC BIODEGRADATION OF A BIODEGRADABLE MATERIAL UNDER ANAEROBIC - THERMOPHILIC DIGESTION

    Directory of Open Access Journals (Sweden)

    RICARDO CAMACHO-MUÑOZ

    2014-12-01

    Full Text Available This paper dertermined the anaerobic biodegradation of a polymer obtained by extrusion process of native cassava starch, polylactic acid and polycaprolactone. Initially a thermophilic - methanogenic inoculum was prepared from urban solid waste. The gas final methane concentration and medium’s pH reached values of 59,6% and 7,89 respectively. The assay assembly was carried out according ASTM D5511 standard. The biodegradation percent of used materials after 15 day of digestion were: 77,49%, 61,27%, 0,31% for cellulose, sample and polyethylene respectively. Due cellulose showed biodegradation levels higher than 70% it’s deduced that the inoculum conditions were appropriate. A biodegradation level of 61,27%, 59,35% of methane concentration in sample’s evolved gas and a medium’s finale pH of 7,71 in sample’s vessels, reveal the extruded polymer´s capacity to be anaerobically degraded under thermophilic- high solid concentration conditions.

  18. Current pain education within undergraduate medical studies across Europe: Advancing the Provision of Pain Education and Learning (APPEAL) study

    Science.gov (United States)

    Briggs, Emma V; Battelli, Daniele; Gordon, David; Kopf, Andreas; Ribeiro, Sofia; Puig, Margarita M; Kress, Hans G

    2015-01-01

    Objectives Unrelieved pain is a substantial public health concern necessitating improvements in medical education. The Advancing the Provision of Pain Education and Learning (APPEAL) study aimed to determine current levels and methods of undergraduate pain medicine education in Europe. Design and methods Using a cross-sectional design, publicly available curriculum information was sought from all medical schools in 15 representative European countries in 2012–2013. Descriptive analyses were performed on: the provision of pain teaching in dedicated pain modules, other modules or within the broader curriculum; whether pain teaching was compulsory or elective; the number of hours/credits spent teaching pain; pain topics; and teaching and assessment methods. Results Curriculum elements were publicly available from 242 of 249 identified schools (97%). In 55% (133/242) of schools, pain was taught only within compulsory non-pain-specific modules. The next most common approaches were for pain teaching to be provided wholly or in part via a dedicated pain module (74/242; 31%) or via a vertical or integrated approach to teaching through the broader curriculum, rather than within any specific module (17/242; 7%). The curricula of 17/242 schools (7%) showed no evidence of any pain teaching. Dedicated pain modules were most common in France (27/31 schools; 87%). Excluding France, only 22% (47/211 schools) provided a dedicated pain module and in only 9% (18/211) was this compulsory. Overall, the median number of hours spent teaching pain was 12.0 (range 4–56.0 h; IQR: 12.0) for compulsory dedicated pain modules and 9.0 (range 1.0–60.0 h; IQR: 10.5) for other compulsory (non-pain specific) modules. Pain medicine was principally taught in classrooms and assessed by conventional examinations. There was substantial international variation throughout. Conclusions Documented pain teaching in many European medical schools falls far short of what might be expected given the

  19. Biodegradable congress 2012; Bioschmierstoff-Kongress 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-01

    Within the Guelzower expert discussions at 5th and 6th June, 2012 in Oberhausen (Federal Republic of Germany) the following lectures were held: (1) Promotion of biodegradable lubricants by means of research and development as well as public relations (Steffen Daebeler); (2) Biodegradable lubricants - An overview of the advantages and disadvantages of the engaged product groups (Hubertus Murrenhoff); (3) Standardization of biodegradable lubricants - CEN/DIN standard committees - state of the art (Rolf Luther); (4) Market research for the utilization of biodegradable lubricants and means of proof of sustainability (Norbert Schmitz); (5) Fields of application for high performance lubricants and requirements upon the products (Gunther Kraft); (6) Investigations of biodegradable lubricants in rolling bearings and gears (Christoph Hentschke); (7) Biodegradable lubricants in central lubrication systems Development of gears and bearings of offshore wind power installations (Reiner Wagner); (8) Investigations towards environmental compatibility of biodegradable lubricants used in offshore wind power installations (Tolf Schneider); (9) Development of glycerine based lubricants for the industrial metalworking (Harald Draeger); (10) Investigations and utilization of biodegradable oils as electroinsulation oils in transformers (Stefan Tenbohlen); (11) Operational behaviour of lubricant oils in vegetable oil operation and Biodiesel operation (Horst Hamdorf); (12) Lubrication effect of lubricating oil of the third generation (Stefan Heitzig); (13) Actual market development from the view of a producer of biodegradable lubricants (Frank Lewen); (14) Utilization of biodegradable lubricants in forestry harvesters (Guenther Weise); (15) New biodegradable lubricants based on high oleic sunflower oil (Otto Botz); (16) Integrated fluid concept - optimized technology and service package for users of biodegradable lubricants (Juergen Baer); (17) Utilization of a bio oil sensor to control

  20. Pengaruh Penambahan Kitosan dalam Pembuatan Biodegradable Foam Berbahan Baku Pati

    Directory of Open Access Journals (Sweden)

    Nanik Hendrawati

    2017-05-01

    Full Text Available Biodegradable foam is an alternative packaging to replace the expanded polystyrene foam packaging currently in use.   Starch has been used to produce foam because of  its low cost, low density, low toxicity, and  biodegradability. Chitosan has been added to improve mechanical properties of product . The   effect of  variation on chitosan amount  and  starch types  was investigated in this study.  The amount of  chitosan  was varied as 0; 5; 10; 15; 20; 25; and  30 % w/w and starch types were used in this research were cassava, Corn and sago starch. Biodegradable  foam was produced by using baking process method, all of material (Starch, Chitosan solution,  Magnesium Stearate, Carrageenan, Glyserol, Protein Isolates  dan polyvinil alcohol (PVOH  were mixed with kitchen aid mixer. The mixture was poured  into mold and heated in an oven at 125 oC for 1 hour. Then, foam was tested for its mechanical properties, water absorption  and biodegradability and  morphology (SEM.  The results show that  foam made from sago starch had lower water absortion than those made from cassava and corn starch.   While, foam made from cassava starch  was more biodegradable than the other foam.  Biodegradable foam based sago starch and 30 % w/w of Chitosan adition  gave the  best performence in tensile stress that  is 20 Mpa

  1. Heat treatment of organics for increasing anaerobic biodegradability. Quarterly progress report, July 1, 1979-September 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Stuckey, D.; Colberg, P.J.; Baugh, K.; Young, L.Y.; McCarty, P.L.

    1979-01-01

    The objective of this study is to evaluate thermochemical pretreatment as a method for increasing the anaerobic biodegradability of organic materials so that they can be more completely fermented to methane gas, a potential source of fuel. The current study has four specific phases: (1) biological conversion of lignocellulose to methane, (2) biodegradation of lignin and lignin fractions, (3) pretreatment of nitrogenous organics for increasing biodegradability, (4) biodegradation of lignin aromatic compounds, and (5) biochemical methane potential and toxicity testing. Results are reported for phases one, two, and three. No new information is available for phases four and five at this time.

  2. Biodegradable polymeric prodrugs of naltrexone

    NARCIS (Netherlands)

    Bennet, D.B.; Li, X.; Adams, N.W.; Kim, S.W.; Hoes, C.J.T.; Hoes, C.J.T.; Feijen, Jan

    1991-01-01

    The development of a biodegradable polymeric drug delivery system for the narcotic antagonist naltrexone may improve patient compliance in the treatment of opiate addiction. Random copolymers consisting of the ¿-amino acids N5-(3-hydroxypropyl--glutamine and -leucine were synthesized with equimolar

  3. Biodegradable poly(lactic acid)

    Indian Academy of Sciences (India)

    The fabrication of biodegradable poly(lactic acid) (PLA) microspheres containing total alkaloids of Caulis sinomenii was investigated. The formation, diameter, morphology and properties of the microspheres were characterized using Fourier transform infrared spectroscopy (FT–IR), laser particle size analyser and scanning ...

  4. Biodegradable Metals for Cardiovascular Stent Application: Interests and New Opportunities

    Directory of Open Access Journals (Sweden)

    Maryam Moravej

    2011-06-01

    Full Text Available During the last decade, biodegradable metallic stents have been developed and investigated as alternatives for the currently-used permanent cardiovascular stents. Degradable metallic materials could potentially replace corrosion-resistant metals currently used for stent application as it has been shown that the role of stenting is temporary and limited to a period of 6–12 months after implantation during which arterial remodeling and healing occur. Although corrosion is generally considered as a failure in metallurgy, the corrodibility of certain metals can be an advantage for their application as degradable implants. The candidate materials for such application should have mechanical properties ideally close to those of 316L stainless steel which is the gold standard material for stent application in order to provide mechanical support to diseased arteries. Non-toxicity of the metal itself and its degradation products is another requirement as the material is absorbed by blood and cells. Based on the mentioned requirements, iron-based and magnesium-based alloys have been the investigated candidates for biodegradable stents. This article reviews the recent developments in the design and evaluation of metallic materials for biodegradable stents. It also introduces the new metallurgical processes which could be applied for the production of metallic biodegradable stents and their effect on the properties of the produced metals.

  5. The development and performance testing of a biodegradable scale inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, Julie; Fidoe, Steve; Jones, Chris

    2006-03-15

    The oil industry is currently facing severe restrictions concerning the discharge of oil field chemicals into the environment. Many commonly used materials in both topside and downhole applications are phased for substitution for use in the North Sea, and more will be identified. The development of biodegradable and low toxicity chemicals, which afford equal or improved efficacy, compared to conventional technology, available at a competitive price, is a current industry challenge. A range of biodegradable materials are increasingly available, however their limited performance can result in a restricted range of applications. This paper discusses the development and commercialization of a readily biodegradable scale inhibitor, ideal for use in topside applications. This material offers a broad spectrum of activity, notably efficiency against barium sulphate, calcium sulphate and calcium carbonate scales, in a range of water chemistries. A range of performance testing, compatibility, stability and OCNS dataset will be presented. Comparisons with commonly used chemicals have been made to identify the superior performance of this phosphate ester. This paper will discuss a scale inhibitor suitable for use in a variety of conditions which offers enhanced performance combined with a favourable biodegradation profile. This material is of great benefit to the industry, particularly in North Sea applications. (author) (tk)

  6. Hematopoietic specification from human pluripotent stem cells: current advances and challenges toward de novo generation of hematopoietic stem cells.

    Science.gov (United States)

    Slukvin, Igor I

    2013-12-12

    Significant advances in cellular reprogramming technologies and hematopoietic differentiation from human pluripotent stem cells (hPSCs) have already enabled the routine production of multiple lineages of blood cells in vitro and opened novel opportunities to study hematopoietic development, model genetic blood diseases, and manufacture immunologically matched cells for transfusion and cancer immunotherapy. However, the generation of hematopoietic cells with robust and sustained multilineage engraftment has not been achieved. Here, we highlight the recent advances in understanding the molecular and cellular pathways leading to blood development from hPSCs and discuss potential approaches that can be taken to facilitate the development of technologies for de novo production of hematopoietic stem cells.

  7. Polymeric Biodegradable Stent Insertion in the Esophagus

    Directory of Open Access Journals (Sweden)

    Kai Yang

    2016-04-01

    Full Text Available Esophageal stent insertion has been used as a well-accepted and effective alternative to manage and improve the quality of life for patients diagnosed with esophageal diseases and disorders. Current stents are either permanent or temporary and are fabricated from either metal or plastic. The partially covered self-expanding metal stent (SEMS has a firm anchoring effect and prevent stent migration, however, the hyperplastic tissue reaction cause stent restenosis and make it difficult to remove. A fully covered SEMS and self-expanding plastic stent (SEPS reduced reactive hyperplasia but has a high migration rate. The main advantage that polymeric biodegradable stents (BDSs have over metal or plastic stents is that removal is not require and reduce the need for repeated stent insertion. But the slightly lower radial force of BDS may be its main shortcoming and a post-implant problem. Thus, strengthening support of BDS is a content of the research in the future. BDSs are often temporarily effective in esophageal stricture to relieve dysphagia. In the future, it can be expect that biodegradable drug-eluting stents (DES will be available to treat benign esophageal stricture, perforations or leaks with additional use as palliative modalities for treating malignant esophageal stricture, as the bridge to surgery or to maintain luminal patency during neoadjuvant chemoradiation.

  8. Additional Equipment for Soil Biodegradation

    Science.gov (United States)

    Vondráčková, Terezie; Kraus, Michal; Šál, Jiří

    2017-12-01

    Intensification of industrial production, increasing citizens’ living standards, expanding the consumer assortment mean in the production - consumption cycle a constantly increasing occurrence of waste material, which by its very nature must be considered as a source of useful raw materials in all branches of human activity. In addition to strict legislative requirements, a number of circumstances characterize waste management. It is mainly extensive transport associated with the handling and storage of large volumes of substances with a large assortment of materials (substances of all possible physical and chemical properties) and high demands on reliability and time coordination of follow-up processes. Considerable differences in transport distances, a large number of sources, processors and customers, and not least seasonal fluctuations in waste and strong price pressures cannot be overlooked. This highlights the importance of logistics in waste management. Soils that are contaminated with oil and petroleum products are hazardous industrial waste. Methods of industrial waste disposal are landfilling, biological processes, thermal processes and physical and chemical methods. The paper focuses on the possibilities of degradation of oil pollution, in particular biodegradation by bacteria, which is relatively low-cost among technologies. It is necessary to win the fight with time so that no ground water is contaminated. We have developed two additional devices to help reduce oil accident of smaller ranges. In the case of such an oil accident, it is necessary to carry out the permeability test of contaminated soil in time and, on this basis, to choose the technology appropriate to the accident - either in-sit biodegradation - at the site of the accident, or on-sit - to remove the soil and biodegrade it on the designated deposits. A special injection drill was developed for in-sit biodegradation, tossing and aeration equipment of the extracted soil was developed for

  9. The second green revolution? Production of plant-based biodegradable plastics.

    Science.gov (United States)

    Mooney, Brian P

    2009-03-01

    Biodegradable plastics are those that can be completely degraded in landfills, composters or sewage treatment plants by the action of naturally occurring micro-organisms. Truly biodegradable plastics leave no toxic, visible or distinguishable residues following degradation. Their biodegradability contrasts sharply with most petroleum-based plastics, which are essentially indestructible in a biological context. Because of the ubiquitous use of petroleum-based plastics, their persistence in the environment and their fossil-fuel derivation, alternatives to these traditional plastics are being explored. Issues surrounding waste management of traditional and biodegradable polymers are discussed in the context of reducing environmental pressures and carbon footprints. The main thrust of the present review addresses the development of plant-based biodegradable polymers. Plants naturally produce numerous polymers, including rubber, starch, cellulose and storage proteins, all of which have been exploited for biodegradable plastic production. Bacterial bioreactors fed with renewable resources from plants--so-called 'white biotechnology'--have also been successful in producing biodegradable polymers. In addition to these methods of exploiting plant materials for biodegradable polymer production, the present review also addresses the advances in synthesizing novel polymers within transgenic plants, especially those in the polyhydroxyalkanoate class. Although there is a stigma associated with transgenic plants, especially food crops, plant-based biodegradable polymers, produced as value-added co-products, or, from marginal land (non-food), crops such as switchgrass (Panicum virgatum L.), have the potential to become viable alternatives to petroleum-based plastics and an environmentally benign and carbon-neutral source of polymers.

  10. Strategy on biological evaluation for biodegradable/absorbable materials and medical devices.

    Science.gov (United States)

    Liu, Chenghu; Luo, Hongyu; Wan, Min; Hou, Li; Wang, Xin; Shi, Yanping

    2018-01-01

    During the last two decades, biodegradable/absorbable materials which have many benefits over conventional implants are being sought in clinical practices. However, to date, it still remains obscure for us to perform full physic-chemical characterization and biological risk assessment for these materials and related devices due to their complex design and coherent processing. In this review, based on the art of knowledge for biodegradable/absorbable materials and biological risk assessment, we demonstrated some promising strategies to establish and improve the current biological evaluation systems for these biodegradable/absorbable materials and related medical devices.

  11. Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project: Current and advanced act control system definition study, volume 1

    Science.gov (United States)

    Hanks, G. W.; Shomber, H. A.; Dethman, H. A.; Gratzer, L. B.; Maeshiro, A.; Gangsaas, D.; Blight, J. D.; Buchan, S. M.; Crumb, C. B.; Dorwart, R. J.

    1981-01-01

    An active controls technology (ACT) system architecture was selected based on current technology system elements and optimal control theory was evaluated for use in analyzing and synthesizing ACT multiple control laws. The system selected employs three redundant computers to implement all of the ACT functions, four redundant smaller computers to implement the crucial pitch-augmented stability function, and a separate maintenance and display computer. The reliability objective of probability of crucial function failure of less than 1 x 10 to the -9th power per flight of 1 hr can be met with current technology system components, if the software is assumed fault free and coverage approaching 1.0 can be provided. The optimal control theory approach to ACT control law synthesis yielded comparable control law performance much more systematically and directly than the classical s-domain approach. The ACT control law performance, although somewhat degraded by the inclusion of representative nonlinearities, remained quite effective. Certain high-frequency gust-load alleviation functions may require increased surface rate capability.

  12. Trend and current practices of palm oil mill effluent polishing: Application of advanced oxidation processes and their future perspectives.

    Science.gov (United States)

    Bello, Mustapha Mohammed; Abdul Raman, Abdul Aziz

    2017-08-01

    Palm oil processing is a multi-stage operation which generates large amount of effluent. On average, palm oil mill effluent (POME) may contain up to 51, 000 mg/L COD, 25,000 mg/L BOD, 40,000 TS and 6000 mg/L oil and grease. Due to its potential to cause environmental pollution, palm oil mills are required to treat the effluent prior to discharge. Biological treatments using open ponding system are widely used for POME treatment. Although these processes are capable of reducing the pollutant concentrations, they require long hydraulic retention time and large space, with the effluent frequently failing to satisfy the discharge regulation. Due to more stringent environmental regulations, research interest has recently shifted to the development of polishing technologies for the biologically-treated POME. Various technologies such as advanced oxidation processes, membrane technology, adsorption and coagulation have been investigated. Among these, advanced oxidation processes have shown potentials as polishing technologies for POME. This paper offers an overview on the POME polishing technologies, with particularly emphasis on advanced oxidation processes and their prospects for large scale applications. Although there are some challenges in large scale applications of these technologies, this review offers some perspectives that could help in overcoming these challenges. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Advances in radiation-hydrodynamics and atomic physics simulation for current and new neutron-less targets

    International Nuclear Information System (INIS)

    Velarde, G.; Minguez, E.; Bravo, E.

    2003-01-01

    We present advances in advanced fusion cycles, atomic physics and radiation hydrodynamics. With ARWEN code we analyze a target design for ICF based on jet production. ARWEN is 2D Adaptive Mesh Refinement fluid dynamic and multigroup radiation transport. We are designing, by using also ARWEN, a target for laboratory simulation of astrophysical phenomena. We feature an experimental device to reproduce collisions of two shock waves, scaled to roughly represent cosmic supernova remnants. Opacity calculations are obtained with ANALOP code, which uses parametric potentials fitting to self-consistent potentials. It includes temperature and density effects by linearized Debye-Hueckel and it treats excited configurations and H+He-like lines. Advanced fusion cycles, as the a neutronic proton-boron 11 reaction, require very high ignition temperatures. Plasma conditions for a fusion-burning wave to propagate at such temperatures are rather extreme and complex, because of the overlapping effects of the main energy transport mechanisms. Calculations on the most appropriate ICF regimes for this purpose are presented. (author)

  14. Application of a Biodegradable Lubricant in a Diesel Vehicle

    DEFF Research Database (Denmark)

    Schramm, Jesper

    2003-01-01

    The IEA Advanced Motor Fuels Agreement has initiated this project concerning the application of biodegradable lubricants to diesel and gasoline type vehicles. Emission measurements on a chassis dynamometer were carried out. The purpose of these measurements was to compare the emissions of CO, CO2......, NOx, THC, PM, lubricant-SOF and PAH from one diesel and one gasoline type vehicle using biodegradable lubricants and conventional lubricants. This paper describes the results of the experiments with the diesel type vehicle only. Lubricant consumption and fuel consumption are other important parameters...... that have been evaluated during the experiments. Both vehicle types were operated on conventional crude oil based fuels and alternative fuels. The diesel vehicle was operated on conventional diesel fuel from a Danish fuel station, low sulfur diesel from Sweden and biodiesel, which was bought at a fuel...

  15. Challenges and opportunities of biodegradable plastics: A mini review.

    Science.gov (United States)

    Rujnić-Sokele, Maja; Pilipović, Ana

    2017-02-01

    The concept of materials coming from nature with environmental advantages of being biodegradable and/or biobased (often referred to as bioplastics) is very attractive to the industry and to the consumers. Bioplastics already play an important role in the fields of packaging, agriculture, gastronomy, consumer electronics and automotive, but still they have a very low share in the total production of plastics (currently about 1% of the about 300 million tonnes of plastic produced annually). Biodegradable plastics are often perceived as the possible solution for the waste problem, but biodegradability is just an additional feature of the material to be exploited at the end of its life in specific terms, in the specific disposal environment and in a specific time, which is often forgotten. They should be used as a favoured choice for the applications that demand a cheap way to dispose of the item after it has fulfilled its job (e.g. for food packaging, agriculture or medical products). The mini-review presents the opportunities and future challenges of biodegradable plastics, regarding processing, properties and waste management options.

  16. Advanced clean coal technology international symposium 2001. Current status of high efficiency coal utilization technology and coal ash utilization

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    Papers are presented under the following session headings: current status of coal utilization technology; movement for environmental control in the USA, EU and Japan; and coal combustion products utilization technologies.

  17. Lignin Biodegradation with Laccase-Mediator Systems

    International Nuclear Information System (INIS)

    Christopher, Lew Paul; Yao, Bin; Ji, Yun

    2014-01-01

    Lignin has a significant and largely unrealized potential as a source for the sustainable production of fuels and bulk high-value chemicals. It can replace fossil-based oil as a renewable feedstock that would bring about socio-economic and environmental benefits in our transition to a biobased economy. The efficient utilization of lignin however requires its depolymerization to low-molecular weight phenolics and aromatics that can then serve as the building blocks for chemical syntheses of high-value products. The ability of laccase to attack and degrade lignin in conjunction with laccase mediators is currently viewed as one of the potential “breakthrough” applications for lignin valorization. Here, we review the recent progress in lignin biodegradation with laccase-mediator systems, and research needs that need to be addressed in this field.

  18. Polyester-Based (Bio)degradable Polymers as Environmentally Friendly Materials for Sustainable Development

    Science.gov (United States)

    Rydz, Joanna; Sikorska, Wanda; Kyulavska, Mariya; Christova, Darinka

    2014-01-01

    This review focuses on the polyesters such as polylactide and polyhydroxyalkonoates, as well as polyamides produced from renewable resources, which are currently among the most promising (bio)degradable polymers. Synthetic pathways, favourable properties and utilisation (most important applications) of these attractive polymer families are outlined. Environmental impact and in particular (bio)degradation of aliphatic polyesters, polyamides and related copolymer structures are described in view of the potential applications in various fields. PMID:25551604

  19. Production of Polyhydroxyalkanoates, a bacterial biodegradable ...

    African Journals Online (AJOL)

    African Journal of Biotechnology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 3, No 1 (2004) >. Log in or Register to get access to full text downloads.

  20. Radiation effects on biodegradable polyesters

    International Nuclear Information System (INIS)

    Hiroshi Mitomo; Darmawan Darwis; Fumio Yoshii; Keizo Makuuchi

    1999-01-01

    Poly(3-hydroxybutyrate) [P(3HB)] and its copolymer poly(3-hydroxybutyrate-co-3hydroxyvalerate) [P(3HB-co-3HV)] are microbial biodegradable polyesters produced by many types of bacteria. Poly(butylene succinate) (PBS) and poly(E-caprolactone) (PCL) are also biodegradable synthetic polyesters which have been commercialized. These thermoplastics are expected for wide usage in environmental protection and blocompatible applications. Radiation grafting of hydrophilic monomers onto many polymers, e.g., polyethylene and polypropylene has been studied mainly for biomedical applications. In the present study, radiation-induced graft polymerization of vinyl monomers onto PHB and P(3HB-co-3HV) was carried out and improvement of their properties was studied. Changes in the properties and biodegradability were compared with the degree of grafting. Radiation-induced crosslinking of PBS and PCL which relatively show thermal and irradiation stability was also carried out to improve their thermal stability or processability. Irradiation to PBS and PCL mainly resulted in crosslinking and characterization of these crosslinked polyesters was investigated

  1. An Official American Thoracic Society Research Statement : Current Challenges Facing Research and Therapeutic Advances in Airway Remodeling

    NARCIS (Netherlands)

    Prakash, Y S; Halayko, Andrew J; Gosens, Reinoud; Panettieri Jr., Reynold A; Camoretti-Mercado, Blanca; Penn, Raymond B; Burgess, Janette K

    2017-01-01

    BACKGROUND: Airway remodeling (AR) is a prominent feature of asthma and other obstructive lung diseases that is minimally affected by current treatments. The goals of this Official American Thoracic Society (ATS) Research Statement are to discuss the scientific, technological, economic, and

  2. Advances in alloimmune thrombocytopenia: perspectives on current concepts of human platelet antigens, antibody detection strategies, and genotyping.

    Science.gov (United States)

    Hayashi, Tomoya; Hirayama, Fumiya

    2015-07-01

    Alloimmunisation to platelets leads to the production of antibodies against platelet antigens and consequently to thrombocytopenia. Numerous molecules located on the platelet surface are antigenic and induce immune-mediated platelet destruction with symptoms that can be serious. Human platelet antigens (HPA) cause thrombocytopenias, such as neonatal alloimmune thrombocytopenia, post-transfusion purpura, and platelet transfusion refractoriness. Thirty-four HPA are classified into 28 systems. Assays to identify HPA and anti-HPA antibodies are critically important for preventing and treating thrombocytopenia caused by anti-HPA antibodies. Significant progress in furthering our understanding of HPA has been made in the last decade: new HPA have been discovered, antibody-detection methods have improved, and new genotyping methods have been developed. We review these advances and discuss issues that remain to be resolved as well as future prospects for preventing and treating immune thrombocytopenia.

  3. Advancing user experience research to facilitate and enable patient-centered research: current state and future directions.

    Science.gov (United States)

    Payne, Philip R O

    2013-01-01

    Human-computer interaction and related areas of user experience (UX) research, such as human factors, workflow evaluation, and data visualization, are thus essential to presenting data in ways that can further the analysis of complex data sets such as those used in patient-centered research. However, a review of available data on the state of UX research as it relates to patient-centered research demonstrates a significant underinvestment and consequently a large gap in knowledge generation. In response, this report explores trends in funding and research productivity focused on UX and patient-centered research and then presents a set of recommendations to advance innovation at this important intersection point. Ultimately, the aim is to catalyze a community-wide dialogue concerning future directions for research and innovation in UX as it applies to patient-centered research.

  4. Advances in Retinal Prosthetic Research: A Systematic Review of Engineering and Clinical Characteristics of Current Prosthetic Initiatives.

    Science.gov (United States)

    Cheng, Derrick L; Greenberg, Paul B; Borton, David A

    2017-03-01

    To date, reviews of retinal prostheses have focused primarily on devices undergoing human trials in the Western Hemisphere and fail to capture significant advances in materials and engineering research in countries such as Japan and Korea, as well as projects in early stages of development. To address these gaps, this systematic review examines worldwide advances in retinal prosthetic research, evaluates engineering characteristics and clinical progress of contemporary device initiatives, and identifies potential directions for future research in the field of retinal prosthetics. A literature search using PubMed, Google Scholar, and IEEExplore was conducted following the PRISMA Guidelines for Systematic Review. Inclusion criteria were peer-reviewed papers demonstrating progress in human or animal trials and papers discussing the prosthetic engineering design. For each initiative, a description of the device, its engineering considerations, and recent clinical results were provided. Ten prosthetic initiatives met our inclusion criteria and were organized by stimulation location. Of these initiatives, four have recently completed human trials, three are undergoing multi- or single-center human trials, and three are undergoing preclinical animal testing. Only the Argus II (FDA 2013, CE 2011) has obtained FDA approval for use in the United States; the Alpha-IMS (CE 2013) has achieved the highest visual acuity using a Landolt-C test to date and is the only device presently undergoing a multicenter clinical trial. Several distinct approaches to retinal stimulation have been successful in eliciting visual precepts in animals and/or humans. However, many clinical needs are still not met and engineering challenges must be addressed before a retinal prosthesis with the capability to fully and safely restore functional vision can be realized.

  5. Current advances in the generation of human iPS cells: implications in cell-based regenerative medicine.

    Science.gov (United States)

    Revilla, Ana; González, Clara; Iriondo, Amaia; Fernández, Bárbara; Prieto, Cristina; Marín, Carlos; Liste, Isabel

    2016-11-01

    Over the last few years, the generation of induced pluripotent stem cells (iPSCs) from human somatic cells has proved to be one of the most potentially useful discoveries in regenerative medicine. iPSCs are becoming an invaluable tool to study the pathology of different diseases and for drug screening. However, several limitations still affect the possibility of applying iPS cell-based technology in therapeutic prospects. Most strategies for iPSCs generation are based on gene delivery via retroviral or lentiviral vectors, which integrate into the host's cell genome, causing a remarkable risk of insertional mutagenesis and oncogenic transformation. To avoid such risks, significant advances have been made with non-integrative reprogramming strategies. On the other hand, although many different kinds of somatic cells have been employed to generate iPSCs, there is still no consensus about the ideal type of cell to be reprogrammed. In this review we present the recent advances in the generation of human iPSCs, discussing their advantages and limitations in terms of safety and efficiency. We also present a selection of somatic cell sources, considering their capability to be reprogrammed and tissue accessibility. From a translational medicine perspective, these two topics will provide evidence to elucidate the most suitable combination of reprogramming strategy and cell source to be applied in each human iPSC-based therapy. The wide variety of diseases this technology could treat opens a hopeful future for regenerative medicine. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  6. Glass Property Models and Constraints for Estimating the Glass to be Produced at Hanford by Implementing Current Advanced Glass Formulation Efforts

    Energy Technology Data Exchange (ETDEWEB)

    Vienna, John D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kim, Dong-Sang [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Skorski, Daniel C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Matyas, Josef [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-07-01

    Recent glass formulation and melter testing data have suggested that significant increases in waste loading in HLW and LAW glasses are possible over current system planning estimates. The data (although limited in some cases) were evaluated to determine a set of constraints and models that could be used to estimate the maximum loading of specific waste compositions in glass. It is recommended that these models and constraints be used to estimate the likely HLW and LAW glass volumes that would result if the current glass formulation studies are successfully completed. It is recognized that some of the models are preliminary in nature and will change in the coming years. Plus the models do not currently address the prediction uncertainties that would be needed before they could be used in plant operations. The models and constraints are only meant to give an indication of rough glass volumes and are not intended to be used in plant operation or waste form qualification activities. A current research program is in place to develop the data, models, and uncertainty descriptions for that purpose. A fundamental tenet underlying the research reported in this document is to try to be less conservative than previous studies when developing constraints for estimating the glass to be produced by implementing current advanced glass formulation efforts. The less conservative approach documented herein should allow for the estimate of glass masses that may be realized if the current efforts in advanced glass formulations are completed over the coming years and are as successful as early indications suggest they may be. Because of this approach there is an unquantifiable uncertainty in the ultimate glass volume projections due to model prediction uncertainties that has to be considered along with other system uncertainties such as waste compositions and amounts to be immobilized, split factors between LAW and HLW, etc.

  7. Biodegradable polymers in Quebec; Les polymeres biodegradables au Quebec

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    Poly-hydroxy-alkanoates (PHA) are natural polymers made from renewable resources and are easily recyclable, hydrolyzable and biodegradable. Thanks to genetic technologies, PHA can be synthesized from plants or bacteria and can be used in various domains ranging from the manufacturing of packing materials to medical applications. Moreover, their properties make them good substitutes of equivalent petroleum-derived compounds. This report makes a status of Quebec's research work on PHAs and presents the three main research centers in which such studies are carried out: the biotechnology research institute, the Mc Gill university and the Polytechnique school of Montreal. (J.S.)

  8. High strength, biodegradable and cytocompatible alpha tricalcium phosphate-iron composites for temporal reduction of bone fractures.

    Science.gov (United States)

    Montufar, E B; Casas-Luna, M; Horynová, M; Tkachenko, S; Fohlerová, Z; Diaz-de-la-Torre, S; Dvořák, K; Čelko, L; Kaiser, J

    2018-04-01

    In this work alpha tricalcium phosphate (α-TCP)/iron (Fe) composites were developed as a new family of biodegradable, load-bearing and cytocompatible materials. The composites with composition from pure ceramic to pure metallic samples were consolidated by pulsed electric current assisted sintering to minimise processing time and temperature while improving their mechanical performance. The mechanical strength of the composites was increased and controlled with the Fe content, passing from brittle to ductile failure. In particular, the addition of 25 vol% of Fe produced a ceramic matrix composite with elastic modulus much closer to cortical bone than that of titanium or biodegradable magnesium alloys and specific compressive strength above that of stainless steel, chromium-cobalt alloys and pure titanium, currently used in clinic for internal fracture fixation. All the composites studied exhibited higher degradation rate than their individual components, presenting values around 200 μm/year, but also their compressive strength did not show a significant reduction in the period required for bone fracture consolidation. Composites showed preferential degradation of α-TCP areas rather than β-TCP areas, suggesting that α-TCP can produce composites with higher degradation rate. The composites were cytocompatible both in indirect and direct contact with bone cells. Osteoblast-like cells attached and spread on the surface of the composites, presenting proliferation rate similar to cells on tissue culture-grade polystyrene and they showed alkaline phosphatase activity. Therefore, this new family of composites is a potential alternative to produce implants for temporal reduction of bone fractures. Biodegradable alpha-tricalcium phosphate/iron (α-TCP/Fe) composites are promising candidates for the fabrication of temporal osteosynthesis devices. Similar to biodegradable metals, these composites can avoid implant removal after bone fracture healing, particularly in

  9. Clinical potential of nintedanib for the second-line treatment of advanced non-small-cell lung cancer: current evidence

    Directory of Open Access Journals (Sweden)

    Rothschild SI

    2014-09-01

    Full Text Available Sacha I Rothschild Department of Internal Medicine, Medical Oncology, University Hospital Basel, Basel, Switzerland Abstract: The therapeutic landscape in non-small-cell lung cancer (NSCLC is changing. The description of molecular alterations leading to NSCLC carcinogenesis and progression (so-called oncogenic driver mutations and the development of targeted agents interfering with the tumor-promoting intracellular signaling pathways have improved the outcome for many patients with advanced/metastatic NSCLC. However, many patients with stage IV NSCLC do not have one of the targetable predictive biomarkers, and are therefore in need of classical chemotherapy. This especially applies to squamous cell cancer. A platinum-based doublet chemotherapy is the standard of care for patients with stage IV NSCLC. As second-line therapies, docetaxel, pemetrexed, and the EGFR tyrosine-kinase inhibitor erlotinib have demonstrated benefit in Phase III randomized trials. Recently, the addition of the angiokinase inhibitor nintedanib to docetaxel has proven efficacious, and is a new treatment option in the second-line setting. Preclinical and clinical data of nintedanib for the treatment of lung cancer patients are reviewed here. Keywords: nintedanib, lung cancer, angiokinase inhibitor, VEGFR, PDGF, FGFR

  10. Current perspectives on the health risks associated with the consumption of advanced glycation end products: recommendations for dietary management

    Directory of Open Access Journals (Sweden)

    Palimeri S

    2015-09-01

    Full Text Available Sotiria Palimeri,* Eleni Palioura,* Evanthia Diamanti-KandarakisEndocrine Unit, Medical School University of Athens, Athens, Greece*These authors contributed equally to this workAbstract: Advanced glycation end products (AGEs constitute a complex group of compounds produced endogenously during the aging process and under conditions of hyperglycemia and oxidative stress. AGEs also have an emerging exogenous origin. Cigarette smoke and diet are the two main exogenous sources of AGEs (glycotoxins. Modern Western diets are rich in AGEs which have been implicated in the pathogenesis of several metabolic and degenerative disorders. Accumulating evidence underlies the beneficial effect of the dietary restriction of AGEs not only in animal studies but also in patients with diabetic complications and metabolic diseases. This article reviews the evidence linking dietary glycotoxins to several disorders from diabetic complications and renal failure to liver dysfunction, female reproduction, eye and cognitive disorders as well as cancer. Furthermore, strategies for AGE reduction are discussed with a focus on dietary modification.Keywords: AGEs, dietary glycotoxins, dietary restriction, PCOS, MSR-1, RAGE

  11. Current Advances and Limitations in Modeling ALS/FTD in a Dish Using Induced Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Wenting Guo

    2017-12-01

    Full Text Available Amyotrophic lateral sclerosis (ALS and frontotemporal dementia (FTD are two age-dependent multifactorial neurodegenerative disorders, which are typically characterized by the selective death of motor neurons and cerebral cortex neurons, respectively. These two diseases share many clinical, genetic and pathological aspects. During the past decade, cell reprogramming technologies enabled researchers to generate human induced pluripotent stem cells (iPSCs from somatic cells. This resulted in the unique opportunity to obtain specific neuronal and non-neuronal cell types from patients which could be used for basic research. Moreover, these in vitro models can mimic not only the familial forms of ALS/FTD, but also sporadic cases without known genetic cause. At present, there have been extensive technical advances in the generation of iPSCs, as well as in the differentiation procedures to obtain iPSC-derived motor neurons, cortical neurons and non-neuronal cells. The major challenge at this moment is to determine whether these iPSC-derived cells show relevant phenotypes that recapitulate complex diseases. In this review, we will summarize the work related to iPSC models of ALS and FTD. In addition, we will discuss potential drawbacks and solutions for establishing more trustworthy iPSC models for both ALS and FTD.

  12. Biodegradation kinetics at low concentrations (

    DEFF Research Database (Denmark)

    Toräng, Lars; Albrechtsen, Hans-Jørgen; Nyholm, Niels

    2000-01-01

    Aerobic biodegradation of 2,4-dichlorophenoxyacetic acid (2,4-D) was studied in groundwater added sediment fines. At concentrations at or below 1 mu g/L of 2,4-D degradation kinetic was of true first order without significant growth of specific degraders and with half-life for mineralization...... in the order of 200 days. Higher concentrations of 2,4-D resulted in a grossly overestimate of the actual degradation rate for concentrations characteristic for Danish found in groundwater....

  13. Investigating the crystal growth behavior of biodegradable polymer blend thin films using in situ atomic force microscopy

    CSIR Research Space (South Africa)

    Malwela, T

    2014-01-01

    Full Text Available This article reports the crystal growth behavior of biodegradable polylactide (PLA)/poly[(butylene succinate)-co-adipate] (PBSA) blend thin films using atomic force microscopy (AFM). Currently, polymer thin films have received increased research...

  14. Evaluation of biodegradation and biocompatibility of collagen ...

    Indian Academy of Sciences (India)

    ing material in tissue engineering applications owing to its excellent biocompatibility and biodegradability [2]. How- ever, its fast biodegradation and low mechanical strength are the foremost issues that limit the further uses of this material. Another extensively studied material is chitosan, a linear polysaccharide derived by ...

  15. Enhancing the biodegradation process of cassava ( Manihot ...

    African Journals Online (AJOL)

    Cassava (Manihot esculenta Crantz) peels have been implicated in serious environmental pollution. This study was aimed at investigating the effect of N.P.K (15:15:15) and microbial inoculants on the biodegradation process of cassava peels. Fresh cassava peels were subjected to biodegradation process for twenty weeks.

  16. Biodegradation of phenol by Pseudomonas pictorum on ...

    African Journals Online (AJOL)

    Biodegradation of phenol using Pseudomonas pictorum (ATCC 23328) a potential biodegradant of phenol was investigated under different operating conditions. Chitin was chosen as a support material and then partially characterized physically and chemically. The pH of the solution was varied over a range of 7 – 9.

  17. Biodegradation of dodecylbenzene solfonate sodium by ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-01-04

    Jan 4, 2010 ... Key words: Branched anionic surfactants, biofilm, biodegradation, silanization. ... polymers, pesticides, oil recovery, textiles and paper ... surfactants are not degraded by microorganisms in the environment. Because of its low biodegradation ability and toxic effects on environment, BAS was forbidden in.

  18. Biodegradation of phenol with immobilized Pseuodomonas putida ...

    African Journals Online (AJOL)

    Biodegradation of phenol with immobilized Pseuodomonas putida activated carbon packed bio-filter tower. ... Comparative study on adsorption and simultaneous adsorption and biodegradation (SAB) of phenol using Pseuodomonas putida (MTCC 1194) in a biofilter tower packed with fresh granular activated carbon (GAC) ...

  19. Nylon biodegradation by lignin-degrading fungi.

    Science.gov (United States)

    Deguchi, T; Kakezawa, M; Nishida, T

    1997-01-01

    The biodegradation of nylon by lignin-degrading fungi was investigated. The fungus IZU-154 significantly degraded nylon-66 membrane under ligninolytic conditions. Nuclear magnetic resonance analysis showed that four end groups, CHO, NHCHO, CH3, and CONH2, were formed in the biodegraded nylon-66 membranes, suggesting that nylon-66 was degraded oxidatively. PMID:8979361

  20. Nylon biodegradation by lignin-degrading fungi.

    OpenAIRE

    Deguchi, T; Kakezawa, M; Nishida, T

    1997-01-01

    The biodegradation of nylon by lignin-degrading fungi was investigated. The fungus IZU-154 significantly degraded nylon-66 membrane under ligninolytic conditions. Nuclear magnetic resonance analysis showed that four end groups, CHO, NHCHO, CH3, and CONH2, were formed in the biodegraded nylon-66 membranes, suggesting that nylon-66 was degraded oxidatively.

  1. Biodegradability of electrostatic photocopier toners | Odokuma ...

    African Journals Online (AJOL)

    Biodegradation was monitored over a 28-day period using changes total organic carbon (TOC), Dissolved organic carbon (DOC) ratio of DOC to TOC (Primary biodegradation) and Biochemical Oxygen Demand (BOD) measurements. At day 0 the BOD for Fresh Sharp, Reused Sharp, Fresh Minolta and Reused Minolta ...

  2. Formulation and Characterization of Biodegradable Medicated ...

    African Journals Online (AJOL)

    (TPA), biodegradation, in vitro drug release using a modified chewing apparatus, and sensory properties. Result: Formulations code MCG-5 and MCG-9 which incorporated glyceryl triacetate and castor oil as plasticizers, respectively, showed a biodegradation score of 2 and 1, respectively, indicating significant.

  3. Biodegradation of bioplastics in natural environments.

    Science.gov (United States)

    Emadian, S Mehdi; Onay, Turgut T; Demirel, Burak

    2017-01-01

    The extensive production of conventional plastics and their use in different commercial applications poses a significant threat to both the fossil fuels sources and the environment. Alternatives called bioplastics evolved during development of renewable resources. Utilizing renewable resources like agricultural wastes (instead of petroleum sources) and their biodegradability in different environments enabled these polymers to be more easily acceptable than the conventional plastics. The biodegradability of bioplastics is highly affected by their physical and chemical structure. On the other hand, the environment in which they are located, plays a crucial role in their biodegradation. This review highlights the recent findings attributed to the biodegradation of bioplastics in various environments, environmental conditions, degree of biodegradation, including the identified bioplastic-degrading microorganisms from different microbial communities. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Advancing current approaches to disease management evaluation: capitalizing on heterogeneity to understand what works and for whom.

    Science.gov (United States)

    Elissen, Arianne M J; Adams, John L; Spreeuwenberg, Marieke; Duimel-Peeters, Inge G P; Spreeuwenberg, Cor; Linden, Ariel; Vrijhoef, Hubertus J M

    2013-03-14

    Evaluating large-scale disease management interventions implemented in actual health care settings is a complex undertaking for which universally accepted methods do not exist. Fundamental issues, such as a lack of control patients and limited generalizability, hamper the use of the 'gold-standard' randomized controlled trial, while methodological shortcomings restrict the value of observational designs. Advancing methods for disease management evaluation in practice is pivotal to learn more about the impact of population-wide approaches. Methods must account for the presence of heterogeneity in effects, which necessitates a more granular assessment of outcomes. This paper introduces multilevel regression methods as valuable techniques to evaluate 'real-world' disease management approaches in a manner that produces meaningful findings for everyday practice. In a worked example, these methods are applied to retrospectively gathered routine health care data covering a cohort of 105,056 diabetes patients who receive disease management for type 2 diabetes mellitus in the Netherlands. Multivariable, multilevel regression models are fitted to identify trends in clinical outcomes and correct for differences in characteristics of patients (age, disease duration, health status, diabetes complications, smoking status) and the intervention (measurement frequency and range, length of follow-up). After a median one year follow-up, the Dutch disease management approach was associated with small average improvements in systolic blood pressure and low-density lipoprotein, while a slight deterioration occurred in glycated hemoglobin. Differential findings suggest that patients with poorly controlled diabetes tend to benefit most from disease management in terms of improved clinical measures. Additionally, a greater measurement frequency was associated with better outcomes, while longer length of follow-up was accompanied by less positive results. Despite concerted efforts to adjust

  5. Current management and future directions in the treatment of advanced renal cell carcinoma-a latin american perspective: 10 years in review.

    Science.gov (United States)

    Smaletz, Oren

    2015-01-01

    The worldwide incidence of kidney cancer is estimated at 337,860 new cases per year in the International Agency for Research on Cancer's GLOBOCAN 2012 update, with an estimated 143,369 deaths annually. Over the past 10 years, there have been significant advances in the treatment of advanced/metastatic renal cell carcinoma, including the development of targeted therapies. Currently recommended first-line treatments include sunitinib, temsirolimus, bevacizumab plus interferon, and pazopanib, or high-dose interleukin-2 or sorafenib for selected patients. Recommended second-line treatments include all of the above agents, as well as everolimus and axitinib. Unfortunately, combination therapies have generally resulted in increased toxicity and little improvement in efficacy. Recent studies focused on identification of predictive biomarkers for responses to specific targeted therapies and have not been successful to date. Despite recent advances in targeted treatment for metastatic renal cell carcinoma, important questions regarding biomarkers of efficacy, and optimal combination and sequencing of agents remain to be answered. This paper reviews literature concerned with first-and second-line treatment of metastatic renal cell carcinoma and will discuss key issues in Latin America.

  6. Reproduction in chinchilla (Chinchilla lanigera): current status of environmental control of gonadal activity and advances in reproductive techniques.

    Science.gov (United States)

    Busso, J M; Ponzio, M F; Fiol de Cuneo, M; Ruiz, R D

    2012-07-01

    A review of the biology of reproduction of chinchilla, focusing on environmental control of the gonadal activity, is presented. Chinchilla is a South American hystricomorph rodent genus currently considered almost extinct in the wild. However, a domestic form is still widespread in breeding farms around the world. Information regarding their reproductive biology has been obtained from studies on captive animals. In the case of Chinchilla lanigera, a seasonal reproductive pattern has been frequently reported in breeding facilities, but factors that might trigger gonadal activity have not been identified. The available information on reproductive productivity in farms worldwide shows a range of 1.2 to 2.4 deliveries per female per yr (with up to 2.1 weaned young per female per yr). Indeed, as found in all rodents, chinchillas can multiply at high fecundity and fertility rates (4 to 6 follicles mature during estrous cycles). Some new research avenues are postulated to improve the control of gonadal activity by means of environmental and/or pharmacologic factors. Furthermore, reproductive techniques that have been validated in chinchilla are reviewed (noninvasive hormone monitoring, semen collection, sperm cryopreservation, estrus induction), and several technical steps are proposed to be able to achieve AI. Because domesticated chinchilla still share some genomic characteristics with their counterparts in the wild, validated reproductive techniques in chinchilla males and females might contribute to the success of breeding programs. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. The Study Into Potential Enhacement Of Metalworking Fluids Biodegradability By The Application Of O3/UV

    Directory of Open Access Journals (Sweden)

    Gerulová Kristína

    2015-06-01

    Full Text Available The increase in mineralization and biodegradability of MWFs by ozone/ultraviolet in comparison with ozone were investigated. Studied were two similar synthetic fluids pre-treated by the combination of the O3/UV advanced oxidative method. Expectations that the pre-treatment could enhance biodegradability of the metalworking fluid were not confirmed. The combined oxidation process at the defined conditions resulted in 1-35 % decrease of the achieved primary degradation level. Samples were prepared from real concentrates and diluted to approximately 350 mg/L of TOC.

  8. Intimately coupling of photolysis accelerates nitrobenzene biodegradation, but sequential coupling slows biodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lihui [Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai 200234 (China); Zhang, Yongming, E-mail: zhym@shnu.edu.cn [Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai 200234 (China); Bai, Qi; Yan, Ning; Xu, Hua [Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai 200234 (China); Rittmann, Bruce E. [Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, Tempe, AZ 85287-5701 (United States)

    2015-04-28

    Highlights: • Intimately coupled UV photolysis accelerated nitrobenzene biodegradation. • NB biodegradation was slowed by accumulation of nitrophenol. • Oxalic acid was a key product of UV photolysis. • Oxalic acid accelerated biodegradation of nitrobenzene and nitrophenol by a co-substrate effect. • Intimate coupling of UV and biodegradation accentuated the benefits of oxalic acid. - Abstract: Photo(cata)lysis coupled with biodegradation is superior to photo(cata)lysis or biodegradation alone for removal of recalcitrant organic compounds. The two steps can be carried out sequentially or simultaneously via intimate coupling. We studied nitrobenzene (NB) removal and mineralization to evaluate why intimate coupling of photolysis with biodegradation was superior to sequential coupling. Employing an internal circulation baffled biofilm reactor, we compared direct biodegradation (B), biodegradation after photolysis (P + B), simultaneous photolysis and biodegradation (P&B), and biodegradation with nitrophenol (NP) and oxalic acid (OA) added individually and simultaneously (B + NP, B + OA, and B + NP + OA); NP and OA were NB’s main UV-photolysis products. Compared with B, the biodegradation rate P + B was lower by 13–29%, but intimately coupling (P&B) had a removal rate that was 10–13% higher; mineralization showed similar trends. B + OA gave results similar to P&B, B + NP gave results similar to P + B, and B + OA + NP gave results between P + B and P&B, depending on the amount of OA and NP added. The photolysis product OA accelerated NB biodegradation through a co-substrate effect, but NP was inhibitory. Although decreasing the UV photolysis time could minimize the inhibition impact of NP in P + B, P&B gave the fastest removal of NB by accentuating the co-substrate effect of OA.

  9. Intimately coupling of photolysis accelerates nitrobenzene biodegradation, but sequential coupling slows biodegradation

    International Nuclear Information System (INIS)

    Yang, Lihui; Zhang, Yongming; Bai, Qi; Yan, Ning; Xu, Hua; Rittmann, Bruce E.

    2015-01-01

    Highlights: • Intimately coupled UV photolysis accelerated nitrobenzene biodegradation. • NB biodegradation was slowed by accumulation of nitrophenol. • Oxalic acid was a key product of UV photolysis. • Oxalic acid accelerated biodegradation of nitrobenzene and nitrophenol by a co-substrate effect. • Intimate coupling of UV and biodegradation accentuated the benefits of oxalic acid. - Abstract: Photo(cata)lysis coupled with biodegradation is superior to photo(cata)lysis or biodegradation alone for removal of recalcitrant organic compounds. The two steps can be carried out sequentially or simultaneously via intimate coupling. We studied nitrobenzene (NB) removal and mineralization to evaluate why intimate coupling of photolysis with biodegradation was superior to sequential coupling. Employing an internal circulation baffled biofilm reactor, we compared direct biodegradation (B), biodegradation after photolysis (P + B), simultaneous photolysis and biodegradation (P&B), and biodegradation with nitrophenol (NP) and oxalic acid (OA) added individually and simultaneously (B + NP, B + OA, and B + NP + OA); NP and OA were NB’s main UV-photolysis products. Compared with B, the biodegradation rate P + B was lower by 13–29%, but intimately coupling (P&B) had a removal rate that was 10–13% higher; mineralization showed similar trends. B + OA gave results similar to P&B, B + NP gave results similar to P + B, and B + OA + NP gave results between P + B and P&B, depending on the amount of OA and NP added. The photolysis product OA accelerated NB biodegradation through a co-substrate effect, but NP was inhibitory. Although decreasing the UV photolysis time could minimize the inhibition impact of NP in P + B, P&B gave the fastest removal of NB by accentuating the co-substrate effect of OA

  10. An Official American Thoracic Society Research Statement: Current Challenges Facing Research and Therapeutic Advances in Airway Remodeling.

    Science.gov (United States)

    Prakash, Y S; Halayko, Andrew J; Gosens, Reinoud; Panettieri, Reynold A; Camoretti-Mercado, Blanca; Penn, Raymond B

    2017-01-15

    Airway remodeling (AR) is a prominent feature of asthma and other obstructive lung diseases that is minimally affected by current treatments. The goals of this Official American Thoracic Society (ATS) Research Statement are to discuss the scientific, technological, economic, and regulatory issues that deter progress of AR research and development of therapeutics targeting AR and to propose approaches and solutions to these specific problems. This Statement is not intended to provide clinical practice recommendations on any disease in which AR is observed and/or plays a role. An international multidisciplinary group from within academia, industry, and the National Institutes of Health, with expertise in multimodal approaches to the study of airway structure and function, pulmonary research and clinical practice in obstructive lung disease, and drug discovery platforms was invited to participate in one internet-based and one face-to-face meeting to address the above-stated goals. Although the majority of the analysis related to AR was in asthma, AR in other diseases was also discussed and considered in the recommendations. A literature search of PubMed was performed to support conclusions. The search was not a systematic review of the evidence. Multiple conceptual, logistical, economic, and regulatory deterrents were identified that limit the performance of AR research and impede accelerated, intensive development of AR-focused therapeutics. Complementary solutions that leverage expertise of academia and industry were proposed to address them. To date, numerous factors related to the intrinsic difficulty in performing AR research, and economic forces that are disincentives for the pursuit of AR treatments, have thwarted the ability to understand AR pathology and mechanisms and to address it clinically. This ATS Research Statement identifies potential solutions for each of these factors and emphasizes the importance of educating the global research community as to the

  11. Primary biodegradation and mineralization of hair shampoos in ...

    African Journals Online (AJOL)

    Two methods, the methylene blue active stain (MBAS) river die away method for monitoring primary biodegradation of surfactants and the ultimate biodegradability method for monitoring mineralization of the total biodegradable organic component in a compound were employed to determine the biodegradability of three ...

  12. Microbial Enzymatic Degradation of Biodegradable Plastics.

    Science.gov (United States)

    Roohi; Bano, Kulsoom; Kuddus, Mohammed; Zaheer, Mohammed R; Zia, Qamar; Khan, Mohammed F; Ashraf, Ghulam Md; Gupta, Anamika; Aliev, Gjumrakch

    2017-01-01

    The renewable feedstock derived biodegradable plastics are important in various industries such as packaging, agricultural, paper coating, garbage bags and biomedical implants. The increasing water and waste pollution due to the available decomposition methods of plastic degradation have led to the emergence of biodegradable plastics and biological degradation with microbial (bacteria and fungi) extracellular enzymes. The microbes utilize biodegradable polymers as the substrate under starvation and in unavailability of microbial nutrients. Microbial enzymatic degradation is suitable from bioremediation point of view as no waste accumulation occurs. It is important to understand the microbial interaction and mechanism involved in the enzymatic degradation of biodegradable plastics under the influence of several environmental factors such as applied pH, thermo-stability, substrate molecular weight and/or complexity. To study the surface erosion of polymer film is another approach for hydrolytic degradation characteristion. The degradation of biopolymer is associated with the production of low molecular weight monomer and generation of carbon dioxide, methane and water molecule. This review reported the degradation study of various existing biodegradable plastics along with the potent degrading microbes (bacteria and fungi). Patents available on plastic biodegradation with biotechnological significance is also summarized in this paper. This paper assesses that new disposal technique should be adopted for the degradation of polymers and further research is required for the economical production of biodegradable plastics along with their enzymatic degradation. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  13. Biodegradable Metals From Concept to Applications

    CERN Document Server

    Hermawan, Hendra

    2012-01-01

    This book in the emerging research field of biomaterials covers biodegradable metals for biomedical applications. The book contains two main parts where each of them consists of three chapters. The first part introduces the readers to the field of metallic biomaterials, exposes the state of the art of biodegradable metals, and reveals its application for cardiovascular implants. It includes some fundamental aspects to give basic understanding on metals for further review on the degradable ones is covered in chapter one. The second chapter introduces the concept of biodegradable metals, it's st

  14. Biodegradation study of some food packaging biopolymers based on PVA

    Directory of Open Access Journals (Sweden)

    Elena Elisabeta Tanase

    2016-03-01

    Full Text Available Abstract Polymers are a common choice as protective materials since they combine flexibility, variable sizes and shapes, relatively light weight, stability, resistance to breaking, barrier properties and perceived high-quality image with cost-effectiveness. Currently, mainly non-biodegradable petroleum-based synthetic polymers are used as packaging materials for foods, because of their availability, low cost and functionality. However, biopolymers can be made from renewable resources without the environmental issues of petroleum-based polymers and with the additional advantage of being available from renewable sources or as by-products or waste-products from the food and agriculture industries. The aim of this study was to test some food packaging biopolymers based on PVA. In this respect, some biopolymers for food packaging applications were subjected to biodegradation tests by covering the tested samples with soil. The samples were incubated in known temperature and humidity conditions. The experiment lasted 45 days, after that the samples were washed, weighed and the biodegradation degree was calculated. The obtained results shows that PVA is a promising material for food packaging usage, as it is made from renewable resources and it is environmentally friendly.

  15. New perspectives in plastic biodegradation.

    Science.gov (United States)

    Sivan, Alex

    2011-06-01

    During the past 50 years new plastic materials, in various applications, have gradually replaced the traditional metal, wood, leather materials. Ironically, the most preferred property of plastics--durability--exerts also the major environmental threat. Recycling has practically failed to provide a safe solution for disposal of plastic waste (only 5% out of 1 trillion plastic bags, annually produced in the US alone, are being recycled). Since the most utilized plastic is polyethylene (PE; ca. 140 million tons/year), any reduction in the accumulation of PE waste alone would have a major impact on the overall reduction of the plastic waste in the environment. Since PE is considered to be practically inert, efforts were made to isolate unique microorganisms capable of utilizing synthetic polymers. Recent data showed that biodegradation of plastic waste with selected microbial strains became a viable solution. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Biodegradable polyesters from renewable resources.

    Science.gov (United States)

    Tsui, Amy; Wright, Zachary C; Frank, Curtis W

    2013-01-01

    Environmental concerns have led to the development of biorenewable polymers with the ambition to utilize them at an industrial scale. Poly(lactic acid) and poly(hydroxyalkanoates) are semicrystalline, biorenewable polymers that have been identified as the most promising alternatives to conventional plastics. However, both are inherently susceptible to brittleness and degradation during thermal processing; we discuss several approaches to overcome these problems to create a balance between durability and biodegradability. For example, copolymers and blends can increase ductility and the thermal-processing window. Furthermore, chain modifications (e.g., branching/crosslinking), processing techniques (fiber drawing/annealing), or additives (plasticizers/nucleating agents) can improve mechanical properties and prevent thermal degradation during processing. Finally, we examine the impacts of morphology on end-of-life degradation to complete the picture for the most common renewable polymers.

  17. Development of inherent technologies for advanced PWR core - A study on the current status and the construction feasibility of critical facilities

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Won Sik; Yang, Hyun Seok [Chosun University, Kwangju (Korea); Kim, Chang Hyo; Shim, Hyung Jin [Seoul National University, Seoul (Korea)

    1999-03-01

    The objective of this study is to examine the appropriateness of constructing critical facilities in our country and to decide a course of constructing them if necessary by surveying the status and utilization of foreign facilities and by investigating the demand for domestic facilities. We investigated the status and the utilization of foreign critical facilities through literature survey and personal visitation. In our judgement, critical facilities are necessary for developing the advanced reactors and fuels which are being studied as parts of the Nuclear R and D Program by MOST. Considering the construction cost and the current state of domestic economy, however, it is unjustifiable to build three different types of critical facilities (the light water, the heavy water, and the fast critical facility). It appears to be reasonable to build a light water critical, considering the construction cost, degree of utilization, and other constraints. (author). 89 refs., 134 figs., 64 tabs.

  18. Fabrication and Optimal Design of Biodegradable Polymeric Stents for Aneurysms Treatments

    Directory of Open Access Journals (Sweden)

    Xue Han

    2017-02-01

    Full Text Available An aneurysm is a balloon-like bulge in the wall of blood vessels, occurring in major arteries of the heart and brain. Biodegradable polymeric stent-assisted coiling is expected to be the ideal treatment of wide-neck complex aneurysms. This paper presents the development of methods to fabricate and optimally design biodegradable polymeric stents for aneurysms treatment. Firstly, a dispensing-based rapid prototyping (DBRP system was developed to fabricate coil and zigzag structures of biodegradable polymeric stents. Then, compression testing was carried out to characterize the radial deformation of the stents fabricated with the coil or zigzag structure. The results illustrated the stent with a zigzag structure has a stronger radial stiffness than the one with a coil structure. On this basis, the stent with a zigzag structure was chosen for the development of a finite element model for simulating the real compression tests. The result showed the finite element model of biodegradable polymeric stents is acceptable within a range of radial deformation around 20%. Furthermore, the optimization of the zigzag structure was performed with ANSYS DesignXplorer, and the results indicated that the total deformation could be decreased by 35.7% by optimizing the structure parameters, which would represent a significant advance of the radial stiffness of biodegradable polymeric stents.

  19. Acceleration of biodegradation by ultraviolet femtosecond laser irradiation to biodegradable polymer

    Science.gov (United States)

    Shibata, Akimichi; Yada, Shuhei; Kondo, Naonari; Terakawa, Mitsuhiro

    2017-02-01

    Biodegradability is a key property of biodegradable polymers for tissue scaffold applications. Among the methods to control biodegradability, laser processing is a simple technique, which enables the alteration of biodegradability even after molding. Since ultrafast laser processing realizes precise processing of biodegradable polymer with less heat affected zone, ultrafast laser processing has the potential to fabricate tissue scaffolds and to control its biodegradability. In this study, we investigate the effect of femtosecond laser wavelength on the biodegradability of PLGA. We evaluated the biodegradability of PLGA irradiated with femtosecond laser pulses at the wavelength of 800, 400, 266 nm by the measurement of the change in mass of PLGA during water immersion. The results of degradation tests indicate that PLGA irradiated with the shorter wavelength show faster water absorption as well as rapid mass decrease. Since the results of X-ray photoelectron spectroscopy analysis indicate that the chemical bonds of PLGA irradiated with the shorter wavelength are dissociated more significantly, the acceleration of the biodegradation could be attributable to the decrease in molecular weight by chemical bond breaking.

  20. Combination of Advanced Oxidation Technologies with Biological Treatment: A General Review

    International Nuclear Information System (INIS)

    Al-Momani; Shawaqfeh, A.

    2007-01-01

    Advanced oxidation processes (AOPs) have been recently proposed as an important wastwater treatment option. This paper provides a broad overview of the use of AOPs alone or combind with a biological process for wastwater treatment and the current state of knowledge about water treatment options. The first part of the paper focuses on combination of AOP's with biological treatment of different kinds of contaminations. Then the review presents methods used to imorove wastwater biodegradability and toxicity measurements as related to coupling processes. The presented STUDIES conclude that the the use AOP'S as a pre-treatment for wastewater is recommended under specific conditions; 1) AOP's can be used efficiently to pre-treat recalcitrant componds, 2) AOP's can be used to enhance the biodegradability of aqueous solutions, 3) Toxic compounds can be converted to non-toxic compounds by means of AOP's 4) Coupling processes(AOP's + biological) give reasonable results in treating wastewater wiyh significant hydraulic retention time (HRT) (Author's) 58 refs

  1. Biodegradation of VX/Water Hydrolysate

    National Research Council Canada - National Science Library

    DeFrank, Joseph

    1997-01-01

    ...-(diisopropylaminoethyl) methyl phosphonothioate was neutralization followed by biodegradation. The treatment of VX with an equimolar amount of water results in the slow, but complete hydrolysis of the phosphorus-sulfur bond...

  2. Biodegradable lubricants - ''the solution for future?''

    International Nuclear Information System (INIS)

    Jahan, A.

    1997-01-01

    The environmental impact of lubricants use concern the direct effects from spills but also the indirect effects such as their lifetime and the emissions from thermal engines. The biodegradable performances and the toxicity are the environmental criteria that must be taken into account in the development and application of lubricants together with their technical performances. This paper recalls first the definition of biodegradable properties of hydrocarbons and the standardized tests, in particular the CEC and AFNOR tests. Then, the biodegradable performances of basic oils (mineral, vegetal, synthetic esters, synthetic hydrocarbons etc..), finite lubricants (hydraulic fluids..) and engine oils is analyzed according to these tests. Finally, the definition of future standards would take into account all the environmental characteristics of the lubricant: biodegradable performances, energy balance (CO 2 , NOx and Hx emissions and fuel savings), eco-toxicity and technical performances (wearing and cleanliness). (J.S.)

  3. Biodegradability and treatability of caprolactam waste

    Energy Technology Data Exchange (ETDEWEB)

    Patel, M.D.; Patel, D.R.

    1977-01-01

    Studies were conducted on the biodegradability and treatment of wastewaters from a plant manufacturing caprolactam. Two-stage biological treatment, with preliminary aeration followed by an oxidation channel, gave an effluent of the desired quality.

  4. MOLECULAR BASIS OF BIODEGRADATION OF CHLOROAROMATIC COMPOUNDS

    Science.gov (United States)

    Chlorinated aromatic hydrocarbons are widely used in industry and agriculture, and comprise the bulk of environmental pollutants. Although simple aromatic compounds are biodegradable by a variety of degradative pathways, their halogenated counterparts are more resistant to bacter...

  5. Formulation and Characterization of Biodegradable Medicated ...

    African Journals Online (AJOL)

    PEG)-600, tributyl citrate, PEG-200, PEG-300, PEG-400, PEG-4000, triethyl citrate and castor oil. The gum formulations were characterized for the following parameters: texture profile analysis (TPA), biodegradation, in vitro drug release using a ...

  6. Biodegradation of PuEDTA and Impacts on Pu Mobility

    Energy Technology Data Exchange (ETDEWEB)

    Bolton, H., Jr.; Rai, D.; Xun, L.

    2004-03-17

    The contamination of many DOE sites by Pu presents a long-term problem because of its long half-life (240,000 yrs) and the low drinking water standard (<10{sup -12} M). EDTA was co-disposed with radionuclides (e.g., Pu, {sup 60}Co), formed strong complexes, and enhanced radionuclide transport at several DOE sites. Biodegradation of EDTA should decrease Pu mobility. One objective of this project was to determine the biodegradation of EDTA in the presence of PuEDTA complexes. The aqueous system investigated at pH 7 (10{sup -4} M EDTA and 10{sup -6} M Pu) contained predominantly Pu(OH){sub 2}EDTA{sup 2-}. The EDTA was degraded at a faster rate in the presence of Pu. As the total concentration of both EDTA and PuEDTA decreased (i.e., 10{sup -5} M EDTA and 10{sup -7} M PuEDTA), the presence of Pu decreased the biodegradation rate of the EDTA. It is currently unclear why the concentration of Pu directly affects the increase/decrease in rate of EDTA biodegradation. The soluble Pu concentration decreased, in agreement with thermodynamic predictions, as the EDTA was biodegraded, indicating that biodegradation of EDTA will decrease Pu mobility when the Pu is initially present as Pu(IV)EDTA. A second objective was to investigate how the presence of competing metals, commonly encountered in geologic media, will influence the speciation and biodegradation of Pu(IV)-EDTA. Studies on the solubilities of Fe(OH){sub 3}(s) and of Fe(OH){sub 3}(s) plus PuO{sub 2}(am) in the presence of EDTA and as a function of pH showed that Fe(III) out competes the Pu(IV) for the EDTA complex, thereby showing that Pu(IV) will not form stable complexes with EDTA for enhanced transport of Pu in Fe(III) dominated subsurface systems. A third objective is to investigate the genes and enzymes involved in EDTA biodegradation. BNC1 can use EDTA and another synthetic chelating agent nitrilotriacetate (NTA) as sole carbon and nitrogen sources. The same catabolic enzymes are responsible for both EDTA and NTA

  7. Monitoring biodegradation of hydrocarbons by stable isotope fractionation

    Science.gov (United States)

    Dorer, Conrad; Fischer, Anko; Herrmann, Steffi; Richnow, Hans-Hermann; Vogt, Carsten

    2010-05-01

    nitrate, sulfate or ferric iron as electron acceptor or using light as energy source [3,4,5]. Significantly different lambda values were also observed for the anaerobic degradation of xylenes initiated by the BSS [5]. The different lambda values obtained for the anaerobic degradation of toluene and xylenes might be caused by slightly different reaction mechanisms of BSS isoenzymes. In comparison, lambda and/or ɛbulk values for the methyl monohydroxylation of toluene with oxygen as co-substrate were significantly different for two tested strains each containing a different toluene attacking enzyme, indicating that specific enzymes for aerobic methyl group oxidation reactions can be detected by CSIA and 2D-CSIA. Our results show that the combined carbon and hydrogen isotope fractionation approach has great potential to elucidate biodegradation pathways of monoaromatic hydrocarbons in microcosm and field studies. Current work focus on (i) 2D-CSIA of aromatic and aliphatic hydrocarbons in degradation experiments using whole cells, and (ii) 2D-CSIA of aromatic hydrocarbons in in vitro experiments using cell extracts. [1] Fischer et al. (2008) Environ. Sci. Technol. 42, 4356-4363 [2] Mancini et al. (2008) Environ. Sci. Technol. 42, 8290-8296 [3] Vogt et al. (2008) Environ. Sci. Technol. 42, 7793-7800 [4] Tobler et al. (2008) Environ. Sci. Technol. 42, 7786-7792 [5] Herrmann et al. (2009) Environ. Microbiol. Reports 1, 535-544

  8. Biodegradation of chlorpyrifos by bacterial genus Pseudomonas.

    Science.gov (United States)

    Gilani, Razia Alam; Rafique, Mazhar; Rehman, Abdul; Munis, Muhammad Farooq Hussain; Rehman, Shafiq Ur; Chaudhary, Hassan Javed

    2016-02-01

    Chlorpyrifos is an organophosphorus pesticide commonly used in agriculture. It is noxious to a variety of organisms that include living soil biota along with beneficial arthropods, fish, birds, humans, animals, and plants. Exposure to chlorpyrifos may cause detrimental effects as delayed seedling emergence, fruit deformities, and abnormal cell division. Contamination of chlorpyrifos has been found about 24 km from the site of its application. There are many physico-chemical and biological approaches to remove organophosphorus pesticides from the ecosystem, among them most promising is biodegradation. The 3,5,6-trichloro-2-pyridinol (TCP) and diethylthiophosphate (DETP) as primary products are made when chlorpyrifos is degraded by soil microorganisms which further break into nontoxic metabolites as CO(2), H(2)O, and NH(3). Pseudomonas is a diversified genus possessing a series of catabolic pathways and enzymes involved in pesticide degradation. Pseudomonas putida MAS-1 is reported to be more efficient in chlorpyrifos degradation by a rate of 90% in 24 h among Pseudomonas genus. The current review analyzed the comparative potential of bacterial species in Pseudomonas genus for degradation of chlorpyrifos thus, expressing an ecofriendly approach for the treatment of environmental contaminants like pesticides. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Advanced Energy Projects FY 1996 research summaries

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    The mission of the Advanced Energy Projects Division (AEP) is to explore the scientific feasibility of novel energy-related concepts. These concepts are typically at an early stage of scientific development and, therefore, are premature for consideration by applied research or technology development programs. The portfolio of projects is dynamic, but reflects the broad role of the Department in supporting research and development for improving the Nation`s energy posture. Topical areas presently receiving support include: alternative energy sources; innovative concepts for energy conversion and storage; alternate pathways to energy efficiency; exploring uses of new scientific discoveries; biologically-based energy concepts; renewable and biodegradable materials; novel materials for energy technology; and innovative approaches to waste treatment and reduction. Summaries of the 70 projects currently being supported are presented. Appendices contain budget information and investigator and institutional indices.

  10. Biodegradation behaviors of cellulose nanocrystals -PVA nanocomposites

    Directory of Open Access Journals (Sweden)

    Mahdi Rohani

    2014-11-01

    Full Text Available In this research, biodegradation behaviors of cellulose nanocrystals-poly vinyl alcohol nanocomposites were investigated. Nanocomposite films with different filler loading levels (3, 6, 9 and 12% by wt were developed by solvent casting method. The effect of cellulose nanocrystals on the biodegradation behaviors of nanocomposite films was studied. Water absorption and water solubility tests were performed by immersing specimens into distilled water. The characteristic parameter of diffusion coefficient and maximum moisture content were determined from the obtained water absorption curves. The water absorption behavior of the nanocomposites was found to follow a Fickian behavior. The maximum water absorption and diffusion coefficients were decreased by increasing the cellulose nanocrystals contents, however the water solubility decrease. The biodegradability of the films was investigated by immersing specimens into cellulase enzymatic solution as well as by burial in soil. The results showed that adding cellulose nanocrystals increase the weight loss of specimens in enzymatic solution but decrease it in soil media. The limited biodegradability of specimens in soil media attributed to development of strong interactions with solid substrates that inhibit the accessibility of functional groups. Specimens with the low degree of hydrolysis underwent extensive biodegradation in both enzymatic and soil media, whilst specimens with the high degree of hydrolysis showed recalcitrance to biodegradation under those conditions.

  11. Biodegradation of acrylic based resins: A review.

    Science.gov (United States)

    Bettencourt, Ana F; Neves, Cristina B; de Almeida, Marise S; Pinheiro, Lídia M; Oliveira, Sofia Arantes e; Lopes, Luís P; Castro, Matilde F

    2010-05-01

    The development of different types of materials with application in dentistry is an area of intense growth and research, due to its importance in oral health. Among the different materials there are the acrylic based resins that have been extensively used either in restorations or in dentures. The objective of this manuscript was to review the acrylic based resins biodegradation phenomena. Specific attention was given to the causes and consequences of materials degradation under the oral environment. Information from scientific full papers, reviews or abstracts published from 1963 to date were included in the review. Published material was searched in dental literature using general and specialist databases, like the PubMED database. Published studies regarding the description of biodegradation mechanisms, in vitro and in vivo release experiments and cell based studies conducted on acrylic based resins or their components were evaluated. Studies related to the effect of biodegradation on the physical and mechanical properties of the materials were also analyzed. Different factors such as saliva characteristics, chewing or thermal and chemical dietary changes may be responsible for the biodegradation of acrylic based resins. Release of potential toxic compounds from the material and change on their physical and mechanical properties are the major consequences of biodegradation. Increasing concern arises from potential toxic effects of biodegradation products under clinical application thus justifying an intensive research in this area. 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  12. Current Capabilities at SNL for the Integration of Small Modular Reactors onto Smart Microgrids Using Sandia's Smart Microgrid Technology High Performance Computing and Advanced Manufacturing.

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Salvador B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-05-01

    Smart grids are a crucial component for enabling the nation’s future energy needs, as part of a modernization effort led by the Department of Energy. Smart grids and smart microgrids are being considered in niche applications, and as part of a comprehensive energy strategy to help manage the nation’s growing energy demands, for critical infrastructures, military installations, small rural communities, and large populations with limited water supplies. As part of a far-reaching strategic initiative, Sandia National Laboratories (SNL) presents herein a unique, three-pronged approach to integrate small modular reactors (SMRs) into microgrids, with the goal of providing economically-competitive, reliable, and secure energy to meet the nation’s needs. SNL’s triad methodology involves an innovative blend of smart microgrid technology, high performance computing (HPC), and advanced manufacturing (AM). In this report, Sandia’s current capabilities in those areas are summarized, as well as paths forward that will enable DOE to achieve its energy goals. In the area of smart grid/microgrid technology, Sandia’s current computational capabilities can model the entire grid, including temporal aspects and cyber security issues. Our tools include system development, integration, testing and evaluation, monitoring, and sustainment.

  13. Dataset on the impact of UV, nitric acid and surfactant treatments on low-density polyethylene biodegradation

    OpenAIRE

    Pathak, Vinay Mohan; Kumar, Navneet

    2017-01-01

    Present investigation evaluates the LDPE (low-density polyethylene) biodegradation efficiency of polymer degrading bacteria along with UV, nitric acid and surfactant treatments. In current scenario LDPE contamination reported as dominant pollutant in terrestrial and aquatic ecosystem due to its expulsion from commercial and domestic practices. Biodegradation serve as an innovative and effective approach to waste management as compared to land filling and burning processes. The outcomes of UV,...

  14. Biodegradability and biodegradation rate of poly(caprolactone)-starch blend and poly(butylene succinate) biodegradable polymer under aerobic and anaerobic environment.

    Science.gov (United States)

    Cho, H S; Moon, H S; Kim, M; Nam, K; Kim, J Y

    2011-03-01

    The biodegradability and the biodegradation rate of two kinds biodegradable polymers; poly(caprolactone) (PCL)-starch blend and poly(butylene succinate) (PBS), were investigated under both aerobic and anaerobic conditions. PCL-starch blend was easily degraded, with 88% biodegradability in 44 days under aerobic conditions, and showed a biodegradation rate of 0.07 day(-1), whereas the biodegradability of PBS was only 31% in 80 days under the same conditions, with a biodegradation rate of 0.01 day(-1). Anaerobic bacteria degraded well PCL-starch blend (i.e., 83% biodegradability for 139 days); however, its biodegradation rate was relatively slow (6.1 mL CH(4)/g-VS day) compared to that of cellulose (13.5 mL CH(4)/g-VS day), which was used as a reference material. The PBS was barely degraded under anaerobic conditions, with only 2% biodegradability in 100 days. These results were consistent with the visual changes and FE-SEM images of the two biodegradable polymers after the landfill burial test, showing that only PCL-starch blend had various sized pinholes on the surface due to attack by microorganisms. This result may be use in deciding suitable final disposal approaches of different types of biodegradable polymers in the future. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Magnesium as a biodegradable and bioabsorbable material for medical implants

    Science.gov (United States)

    Brar, Harpreet S.; Platt, Manu O.; Sarntinoranont, Malisa; Martin, Peter I.; Manuel, Michele V.

    2009-09-01

    For many years, stainless steel, cobalt-chromium, and titanium alloys have been the primary biomaterials used for load-bearing applications. However, as the need for structural materials in temporary implant applications has grown, materials that provide short-term structural support and can be reabsorbed into the body after healing are being sought. Since traditional metallic biomaterials are typically biocompatible but not biodegradable, the potential for magnesium-based alloys in biomedical applications has gained more interest. This paper summarizes the history and current status of magnesium as a bioabsorbable implant material. Also discussed is the development of a magnesium-zinc-calcium alloy that demonstrates promising degradation behavior.

  16. Biodegradable Polymer-Based Scaffolds for Bone Tissue Engineering

    CERN Document Server

    Sultana, Naznin

    2013-01-01

    This book addresses the principles, methods and applications of biodegradable polymer based scaffolds for bone tissue engineering. The general principle of bone tissue engineering is reviewed and the traditional and novel scaffolding materials, their properties and scaffold fabrication techniques are explored. By acting as temporary synthetic extracellular matrices for cell accommodation, proliferation, and differentiation, scaffolds play a pivotal role in tissue engineering. This book does not only provide the comprehensive summary of the current trends in scaffolding design but also presents the new trends and directions for scaffold development for the ever expanding tissue engineering applications.

  17. Use Of Biodegradation Ratios In Monitoring Trend Of Biostimulated Biodegradation In Crude Oil Polluted Soils

    Directory of Open Access Journals (Sweden)

    Okorondu

    2017-03-01

    Full Text Available This study deals with biodegradation experiment on soil contaminated with crude oil. The soil sample sets A BC D E F G were amended with inorganic fertilizer to enhance microbial growth and hydrocarbon degradation moisture content of some of the sets were as well varied. Biodegradation ratios nC17Pr nC18Ph and nC17nC18PrPh were used to monitor biodegradation of soil sets A BC D E F G for a period of 180. The soil samples were each contaminated with the same amount of crude oil and exposed to specific substrate treatment regarding the amount of nutrients and water content over the same period of time. The trend in biodegradation of the different soil sample sets shows that biodegradation ratio nC17nC18PrPh was more reflective of and explains the biodegradation trend in all the sample sets throughout the period of the experiment hence a better parameter ratio for monitoring trend of biostimulated biodegradation. The order of preference of the biodegradation ratios is expressed as nC18Ph nC17Pr nC17nC18 PrPh. This can be a relevant support tool when designing bioremediation plan on field.

  18. Biodegradation of mineral oils – A review | Aluyor | African Journal of ...

    African Journals Online (AJOL)

    Due to the poor biodegradation rates observable for mineral oils, various methods of bioremediation are currently being researched, with the isolation of various microbial species with the ability to use up mineral oils as a carbon and energy source. Ultimately, vegetable oil based hydraulic fluids will come to the fore as a ...

  19. A prospective clinical evaluation of biodegradable neurolac nerve guides for sensory nerve repair in the hand

    NARCIS (Netherlands)

    Bertleff, MJOE; Meek, MF; Nicolai, JPA

    Purpose: Our purpose was to study the recovery of sensory nerve function, after treatment of traumatic peripheral nerve lesions with a biodegradable poly(DL-lactide-ε-caprolactone) Neurolac nerve guide (Polyganics B.V., Groningen, the Netherlands) versus the current standard reconstruction

  20. Bacterial biodegradation of neonicotinoid pesticides in soil and water systems.

    Science.gov (United States)

    Hussain, Sarfraz; Hartley, Carol J; Shettigar, Madhura; Pandey, Gunjan

    2016-12-01

    Neonicotinoids are neurotoxic systemic insecticides used in plant protection worldwide. Unfortunately, application of neonicotinoids affects both beneficial and target insects indiscriminately. Being water soluble and persistent, these pesticides are capable of disrupting both food chains and biogeochemical cycles. This review focuses on the biodegradation of neonicotinoids in soil and water systems by the bacterial community. Several bacterial strains have been isolated and identified as capable of transforming neonicotinoids in the presence of an additional carbon source. Environmental parameters have been established for accelerated transformation in some of these strains. Studies have also indicated that enhanced biotransformation of these pesticides can be accomplished by mixed microbial populations under optimised environmental conditions. Substantial research into the identification of neonicotinoid-mineralising bacterial strains and identification of the genes and enzymes responsible for neonicotinoid degradation is still required to complete the understanding of microbial biodegradation pathways, and advance bioremediation efforts. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Effects of Ultraviolet Photon Irradiation on the Dielectric Properties of Biodegradable Polymers

    Science.gov (United States)

    Yamaguchi, Yuya; Uchibori, Nao; Ohki, Yoshimichi

    Three kinds of biodegradable polymers, poly-L-lactic acid (PLLA), polybutylene succinate (PBS), and polybutylene succinate adipate (PBSA), and low-density polyethylene (LDPE) as a reference were irradiated for 30 minutes by ultraviolet (UV) photons from a KrCl excimer lamp. It has become clear that the three biodegradable polymers are far more susceptible to UV photons than LDPE since they absorb UV photons very intensely in the vicinity of the irradiated surface. Space charge distribution profiles show that charge carriers are trapped near the irradiated surface. The conduction current increases by the UV-irradiation in all the biodegradable polymers. Instrumental analyses show that the samples were decomposed by photoinduced oxidation. Furthermore, the absorption spectra indicate the appearance of conjugated double bonds. Such structural changes induced seem to be responsible for the higher conductivity and the charge trapping.

  2. Biodegradation of marine oil spills in the Arctic with a Greenland perspective

    DEFF Research Database (Denmark)

    Vergeynst, Leendert; Wegeberg, Susse; Aamand, Jens

    2018-01-01

    , and in particular in its pristine areas, the self-cleaning capacity and biodegradation potential of the natural microbial communities have yet to be uncovered. This review compiles and investigates the current knowledge with respect to environmental parameters and biochemical constraints that control oil...... biodegradation in the Arctic. Hereby, seawaters off Greenland are considered as a case study. Key factors for biodegradation include the bioavailability of hydrocarbons, the presence of hydro-carbon-degrading bacteria and the availability of nutrients. We show how these key factors may be influenced...... water masses, and massive phytoplankton blooms and suspended sediment plumes merit to be topics of future investigation. (c) 2018 Elsevier B.V. All rights reserved....

  3. Biodegradation of Moringa oleifera's polymer blends.

    Science.gov (United States)

    Finzi-Quintão, Cristiane Medina; Novack, Kátia Monteiro; Bernardes-Silva, Ana Cláudia; Silva, Thais D; Moreira, Lucas E S; Braga, Luiza E M

    2017-11-10

    Vegetable oils are used as a base for the synthesis of polymers and monomers with structures similar to that of petroleum, as plasticizers for conventional polymers and biodegrading additives. The Moringa oleifera oil was extracted from seeds and polymerized after being submitted to 16 h of microwave irradiation without catalysers. This polymer was characterized and the efficiency of the oil polymerization was verified by the reduction of double bonds and the increase of molecular weight up to 50,000 g mol -1 . Films produced by a mixture of low-density polyethylene (LDPE) with poly(butylene adipate-co-terephthalate)/poly(lactic acid) (PBAT/PLA) present low tensile resistance and low biodegradation behaviour. In order to improve those properties, the Moringa polymer (PMO) was mixed with LDPE and PBAT/PLA in specific mass concentrations. The films produced with this mixture were characterized and submitted to biodegradation analysis. The PMO behaves as a compatibilizer by improving thermal properties, reducing the crystalline phase and improving the biodegradation behaviour. The biodegradation improved up to five times in comparison to conventional polymers and it restores the mechanical properties.

  4. Biodegradable compounds: Rheological, mechanical and thermal properties

    Science.gov (United States)

    Nobile, Maria Rossella; Lucia, G.; Santella, M.; Malinconico, M.; Cerruti, P.; Pantani, R.

    2015-12-01

    Recently great attention from industry has been focused on biodegradable polyesters derived from renewable resources. In particular, PLA has attracted great interest due to its high strength and high modulus and a good biocompatibility, however its brittleness and low heat distortion temperature (HDT) restrict its wide application. On the other hand, Poly(butylene succinate) (PBS) is a biodegradable polymer with a low tensile modulus but characterized by a high flexibility, excellent impact strength, good thermal and chemical resistance. In this work the two aliphatic biodegradable polyesters PBS and PLA were selected with the aim to obtain a biodegradable material for the industry of plastic cups and plates. PBS was also blended with a thermoplastic starch. Talc was also added to the compounds because of its low cost and its effectiveness in increasing the modulus and the HDT of polymers. The compounds were obtained by melt compounding in a single screw extruder and the rheological, mechanical and thermal properties were investigated. The properties of the two compounds were compared and it was found that the values of the tensile modulus and elongation at break measured for the PBS/PLA/Talc compound make it interesting for the production of disposable plates and cups. In terms of thermal resistance the compounds have HDTs high enough to contain hot food or beverages. The PLA/PBS/Talc compound can be, then, considered as biodegradable substitute for polystyrene for the production of disposable plates and cups for hot food and beverages.

  5. Critical review of the current and future challenges associated with advanced in vitro systems towards the study of nanoparticle (secondary) genotoxicity.

    Science.gov (United States)

    Evans, Stephen J; Clift, Martin J D; Singh, Neenu; de Oliveira Mallia, Jefferson; Burgum, Michael; Wills, John W; Wilkinson, Thomas S; Jenkins, Gareth J S; Doak, Shareen H

    2017-01-01

    With the need to understand the potential biological impact of the plethora of nanoparticles (NPs) being manufactured for a wide range of potential human applications, due to their inevitable human exposure, research activities in the field of NP toxicology has grown exponentially over the last decade. Whilst such increased research efforts have elucidated an increasingly significant knowledge base pertaining to the potential human health hazard posed by NPs, understanding regarding the possibility for NPs to elicit genotoxicity is limited. In vivo models are unable to adequately discriminate between the specific modes of action associated with the onset of genotoxicity. Additionally, in line with the recent European directives, there is an inherent need to move away from invasive animal testing strategies. Thus, in vitro systems are an important tool for expanding our mechanistic insight into NP genotoxicity. Yet uncertainty remains concerning their validity and specificity for this purpose due to the unique challenges presented when correlating NP behaviour in vitro and in vivo This review therefore highlights the current state of the art in advanced in vitro systems and their specific advantages and disadvantages from a NP genotoxicity testing perspective. Key indicators will be given related to how these systems might be used or improved to enhance understanding of NP genotoxicity. © The Author 2016. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society.

  6. Biodegradability of degradable plastic waste.

    Science.gov (United States)

    Agamuthu, P; Faizura, Putri Nadzrul

    2005-04-01

    Plastic waste constitutes the third largest waste volume in Malaysian municipal solid waste (MSW), next to putrescible waste and paper. The plastic component in MSW from Kuala Lumpur averages 24% (by weight), whereas the national mean is about 15%. The 144 waste dumps in the country receive about 95% of the MSW, including plastic waste. The useful life of the landfills is fast diminishing as the plastic waste stays un-degraded for more than 50 years. In this study the compostability of polyethylene and pro-oxidant additive-based environmentally degradable plastics (EDP) was investigated. Linear low-density polyethylene (LLDPE) samples exposed hydrolytically or oxidatively at 60 degrees C showed that the abiotic degradation path was oxidative rather than hydrolytic. There was a weight loss of 8% and the plastic has been oxidized as shown by the additional carbonyl group exhibited in the Fourier transform infra red (FTIR) Spectrum. Oxidation rate seemed to be influenced by the amount of pro-oxidant additive, the chemical structure and morphology of the plastic samples, and the surface area. Composting studies during a 45-day experiment showed that the percentage elongation (reduction) was 20% for McD samples [high-density polyethylene, (HDPE) with 3% additive] and LL samples (LLDPE with 7% additive) and 18% reduction for totally degradable plastic (TDP) samples (HDPE with 3% additive). Lastly, microbial experiments using Pseudomonas aeroginosa on carbon-free media with degradable plastic samples as the sole carbon source, showed confirmatory results. A positive bacterial growth and a weight loss of 2.2% for degraded polyethylene samples were evident to show that the degradable plastic is biodegradable.

  7. Biodegradable and biomimetic elastomeric scaffolds for tissue-engineered heart valves.

    Science.gov (United States)

    Xue, Yingfei; Sant, Vinayak; Phillippi, Julie; Sant, Shilpa

    2017-01-15

    Valvular heart diseases are the third leading cause of cardiovascular disease, resulting in more than 25,000 deaths annually in the United States. Heart valve tissue engineering (HVTE) has emerged as a putative treatment strategy such that the designed construct would ideally withstand native dynamic mechanical environment, guide regeneration of the diseased tissue and more importantly, have the ability to grow with the patient. These desired functions could be achieved by biomimetic design of tissue-engineered constructs that recapitulate in vivo heart valve microenvironment with biomimetic architecture, optimal mechanical properties and possess suitable biodegradability and biocompatibility. Synthetic biodegradable elastomers have gained interest in HVTE due to their excellent mechanical compliance, controllable chemical structure and tunable degradability. This review focuses on the state-of-art strategies to engineer biomimetic elastomeric scaffolds for HVTE. We first discuss the various types of biodegradable synthetic elastomers and their key properties. We then highlight tissue engineering approaches to recreate some of the features in the heart valve microenvironment such as anisotropic and hierarchical tri-layered architecture, mechanical anisotropy and biocompatibility. Heart valve tissue engineering (HVTE) is of special significance to overcome the drawbacks of current valve replacements. Although biodegradable synthetic elastomers have emerged as promising materials for HVTE, a mature HVTE construct made from synthetic elastomers for clinical use remains to be developed. Hence, this review summarized various types of biodegradable synthetic elastomers and their key properties. The major focus that distinguishes this review from the current literature is the thorough discussion on the key features of native valve microenvironments and various up-and-coming approaches to engineer synthetic elastomers to recreate these features such as anisotropic tri

  8. Introduction of environmentally degradable parameters to evaluate the biodegradability of biodegradable polymers.

    Science.gov (United States)

    Guo, Wenbin; Tao, Jian; Yang, Chao; Song, Cunjiang; Geng, Weitao; Li, Qiang; Wang, Yuanyuan; Kong, Meimei; Wang, Shufang

    2012-01-01

    Environmentally Degradable Parameter ((Ed)K) is of importance in the describing of biodegradability of environmentally biodegradable polymers (BDPs). In this study, a concept (Ed)K was introduced. A test procedure of using the ISO 14852 method and detecting the evolved carbon dioxide as an analytical parameter was developed, and the calculated (Ed)K was used as an indicator for the ultimate biodegradability of materials. Starch and polyethylene used as reference materials were defined as the (Ed)K values of 100 and 0, respectively. Natural soil samples were inoculated into bioreactors, followed by determining the rates of biodegradation of the reference materials and 15 commercial BDPs over a 2-week test period. Finally, a formula was deduced to calculate the value of (Ed)K for each material. The (Ed)K values of the tested materials have a positive correlation to their biodegradation rates in the simulated soil environment, and they indicated the relative biodegradation rate of each material among all the tested materials. Therefore, the (Ed)K was shown to be a reliable indicator for quantitatively evaluating the potential biodegradability of BDPs in the natural environment.

  9. Introduction of Environmentally Degradable Parameters to Evaluate the Biodegradability of Biodegradable Polymers

    Science.gov (United States)

    Yang, Chao; Song, Cunjiang; Geng, Weitao; Li, Qiang; Wang, Yuanyuan; Kong, Meimei; Wang, Shufang

    2012-01-01

    Environmentally Degradable Parameter (Ed K) is of importance in the describing of biodegradability of environmentally biodegradable polymers (BDPs). In this study, a concept Ed K was introduced. A test procedure of using the ISO 14852 method and detecting the evolved carbon dioxide as an analytical parameter was developed, and the calculated Ed K was used as an indicator for the ultimate biodegradability of materials. Starch and polyethylene used as reference materials were defined as the Ed K values of 100 and 0, respectively. Natural soil samples were inoculated into bioreactors, followed by determining the rates of biodegradation of the reference materials and 15 commercial BDPs over a 2-week test period. Finally, a formula was deduced to calculate the value of Ed K for each material. The Ed K values of the tested materials have a positive correlation to their biodegradation rates in the simulated soil environment, and they indicated the relative biodegradation rate of each material among all the tested materials. Therefore, the Ed K was shown to be a reliable indicator for quantitatively evaluating the potential biodegradability of BDPs in the natural environment. PMID:22675455

  10. Biodegradable Polymers in Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Leon E. Govaert

    2009-07-01

    Full Text Available The use ofdegradable polymers in medicine largely started around the mid 20th century with their initial use as in vivo resorbing sutures. Thorough knowledge on this topic as been gained since then and the potential applications for these polymers were, and still are, rapidly expanding. After improving the properties of lactic acid-based polymers, these were no longer studied only from a scientific point of view, but also for their use in bone surgery in the 1990s. Unfortunately, after implanting these polymers, different foreign body reactions ranging from the presence of white blood cells to sterile sinuses with resorption of the original tissue were observed. This led to the misconception that degradable polymers would, in all cases, lead to inflammation and/or osteolysis at the implantation site. Nowadays, we have accumulated substantial knowledge on the issue of biocompatibility of biodegradable polymers and are able to tailor these polymers for specific applications and thereby strongly reduce the occurrence of adverse tissue reactions. However, the major issue of biofunctionality, when mechanical adaptation is taken into account, has hitherto been largely unrecognized. A thorough understanding of how to improve the biofunctionality, comprising biomechanical stability, but also visualization and sterilization of the material, together with the avoidance of fibrotic tissue formation and foreign body reactions, may greatly enhance the applicability and safety of degradable polymers in a wide area of tissue engineering applications. This review will address our current understanding of these biofunctionality factors, and will subsequently discuss the pitfalls remaining and potential solutions to solve these problems.

  11. Biodegradable Polymers and Stem Cells for Bioprinting

    Directory of Open Access Journals (Sweden)

    Meijuan Lei

    2016-04-01

    Full Text Available It is imperative to develop organ manufacturing technologies based on the high organ failure mortality and serious donor shortage problems. As an emerging and promising technology, bioprinting has attracted more and more attention with its super precision, easy reproduction, fast manipulation and advantages in many hot research areas, such as tissue engineering, organ manufacturing, and drug screening. Basically, bioprinting technology consists of inkjet bioprinting, laser-based bioprinting and extrusion-based bioprinting techniques. Biodegradable polymers and stem cells are common printing inks. In the printed constructs, biodegradable polymers are usually used as support scaffolds, while stem cells can be engaged to differentiate into different cell/tissue types. The integration of biodegradable polymers and stem cells with the bioprinting techniques has provided huge opportunities for modern science and technologies, including tissue repair, organ transplantation and energy metabolism.

  12. Biodegradable Polymers and Stem Cells for Bioprinting.

    Science.gov (United States)

    Lei, Meijuan; Wang, Xiaohong

    2016-04-29

    It is imperative to develop organ manufacturing technologies based on the high organ failure mortality and serious donor shortage problems. As an emerging and promising technology, bioprinting has attracted more and more attention with its super precision, easy reproduction, fast manipulation and advantages in many hot research areas, such as tissue engineering, organ manufacturing, and drug screening. Basically, bioprinting technology consists of inkjet bioprinting, laser-based bioprinting and extrusion-based bioprinting techniques. Biodegradable polymers and stem cells are common printing inks. In the printed constructs, biodegradable polymers are usually used as support scaffolds, while stem cells can be engaged to differentiate into different cell/tissue types. The integration of biodegradable polymers and stem cells with the bioprinting techniques has provided huge opportunities for modern science and technologies, including tissue repair, organ transplantation and energy metabolism.

  13. Biodegradation of dissolved humic substances by fungi.

    Science.gov (United States)

    Collado, Sergio; Oulego, Paula; Suárez-Iglesias, Octavio; Díaz, Mario

    2018-04-01

    Humic and fulvic acids constitute humic substances, a complex mixture of many different acids containing carboxyl and phenolate groups, which are not only the principal soil fertility factors but also the main pollutants present in landfill leachates or natural organic matter in water. Due to their low bacterial biodegradability, fungal biodegradation processes are key for their removal. The present study compiles and comments all the available literature on decomposition of aqueous humic substances by fungi or by their extracellular enzymes alone, focusing on the influence of the reaction conditions. The biodegradation extent mainly depends on the characteristics and concentration of the humic compounds, the type of microorganisms selected, the inoculation mode, the C and N sources, the presence of certain chemicals in the medium, the availability of oxygen, the temperature, and the pH.

  14. Biodegradable polyesters based on succinic acid

    Directory of Open Access Journals (Sweden)

    Nikolić Marija S.

    2003-01-01

    Full Text Available Two series of aliphatic polyesters based on succinic acid were synthesized by copolymerization with adipic acid for the first series of saturated polyesters, and with fumaric acid for the second series. Polyesters were prepared starting from the corresponding dimethyl esters and 1,4-butanediol by melt transesterification in the presence of a highly effective catalyst tetra-n-butyl-titanate, Ti(0Bu4. The molecular structure and composition of the copolyesters was determined by 1H NMR spectroscopy. The effect of copolymer composition on the physical and thermal properties of these random polyesters were investigated using differential scanning calorimetry. The degree of crystallinity was determined by DSC and wide angle X-ray. The degrees of crystallinity of the saturated and unsaturated copolyesters were generally reduced with respect to poly(butylene succinate, PBS. The melting temperatures of the saturated polyesters were lower, while the melting temperatures of the unsaturated copolyesters were higher than the melting temperature of PBS. The biodegradability of the polyesters was investigated by enzymatic degradation tests. The enzymatic degradation tests were performed in a buffer solution with Candida cylindracea lipase and for the unsaturated polyesters with Rhizopus arrhizus lipase. The extent of biodegradation was quantified as the weight loss of polyester films. Also the surface of the polyester films after degradation was observed using optical microscopy. It could be concluded that the biodegradability depended strongly on the degree of crystallinity, but also on the flexibility of the chain backbone. The highest biodegradation was observed for copolyesters containing 50 mol.% of adipic acid units, and in the series of unsaturated polyesters for copolyesters containing 5 and 10 mol.% of fumarate units. Although the degree of crystallinity of the unsaturated polyesters decreased slightly with increasing unsaturation, the biodegradation

  15. Histological evaluation of different biodegradable and non-biodegradable membranes implanted subcutaneously in rats

    DEFF Research Database (Denmark)

    Zhao, S; Pinholt, E M; Madsen, J E

    2000-01-01

    Different types of biodegradable membranes have become available for guided tissue regeneration. The purpose of this study was to evaluate histologically three different biodegradable membranes (Bio-Gide, Resolut and Vicryl) and one non-biodegradable membrane (expanded polytetrafluoroethylene/e-PTFE...... that e-PTFE was well tolerated and encapsulated by a fibrous connective tissue capsule. There was capsule formation around Resolut and Vicryl and around Bio-Gide in the early phase there was a wide inflammatory zone already. e-PTFE and Vicryl were stable materials while Resolut and Bio-Gide fragmented...

  16. Biodegradable containers from green waste materials

    Science.gov (United States)

    Sartore, Luciana; Schettini, Evelia; Pandini, Stefano; Bignotti, Fabio; Vox, Giuliano; D'Amore, Alberto

    2016-05-01

    Novel biodegradable polymeric materials based on protein hydrolysate (PH), derived from waste products of the leather industry, and poly(ethylene glycol) diglycidyl ether (PEG) or epoxidized soybean oil (ESO) were obtained and their physico-chemical properties and mechanical behaviour were evaluated. Different processing conditions and the introduction of fillers of natural origin, as saw dust and wood flour, were used to tailor the mechanical properties and the environmental durability of the product. The biodegradable products, which are almost completely manufactured from renewable-based raw materials, look promising for several applications, particularly in agriculture for the additional fertilizing action of PH or in packaging.

  17. Biodegradation of Crystal Violet by Agrobacterium radiobacter

    DEFF Research Database (Denmark)

    Parshetti, G.K.; Parshetti, S.G.; Telke, A.A.

    2011-01-01

    Violet (100 mg/L) was studied, maximum decolorization was observed with 15% inoculum concentration. A significant increase in the activities of laccase (184%) and aminopyrine Af-demethylase (300%) in cells obtained after decolorization indicated the involvement of these enzymes in decolorization process...... and phenol. We proposed the hypothetical metabolic pathway of Crystal Violet biodegradation by A. radiobacter. Phytotoxicity and microbial toxicity study showed that Crystal Violet biodegradation metabolites were less toxic to bacteria (A. radiobacter, P. aurugenosa and A. vinelandii) contributing to soil...

  18. Biodegradable multifunctional oil production chemicals: Thermal polyaspartates

    International Nuclear Information System (INIS)

    Ross, R.J.; Ravenscroft, P.D.

    1996-01-01

    The paper deals with biodegradable oil production chemicals. Control of both mineral scale and corrosion with a single, environmentally acceptable material is an ambitious goal. Polyaspartate polymers represent a significant milestone in the attainment of this goal. Thermal polyaspartates (TPA) are polycarboxylate polymers derived via thermal condensation of the naturally occurring amino acid aspartic acid. These protein-like polymers are highly biodegradable and non-toxic, and are produced by an environmentally benign manufacturing process. TPAs exhibit excellent mineral scale inhibition activity and CO 2 corrosion control. Laboratory data on scale inhibition and corrosion control in the North Sea oil field production applications is presented. 8 refs., 2 figs., 6 tabs

  19. Anaerobic biodegradability and treatment of Egyption domestic sewage

    NARCIS (Netherlands)

    Elmitwally, T.A.; Al-Sarawey, A.; El-Sherbiny, M.F.; Zeeman, G.; Lettinga, G.

    2003-01-01

    The anaerobic biodegradability of domestic sewage for four Egyptian villages and four Egyptian cities was determined in batch experiments. The results showed that the biodegradability of the Egyptian-villages sewage (73%) was higher than that of the cities (66%). The higher biodegradability of the

  20. Preparation and characterization of biodegradable poly(vinyl alcohol)

    African Journals Online (AJOL)

    Preparation and characterization of biodegradable poly(vinyl alcohol)/starch blends. ... Their mechanical properties, biodegradability and surface morphology were estimated and studied. The poly(vinyl alcohol)/starch blends show good ... Keywords: Starch, Acetylation, Biodegradation, Poly(vinyl alcohol), Polymer blend.

  1. Mass transfer analysis for terephthalic acid biodegradation by ...

    African Journals Online (AJOL)

    Biodegradation of terephthalic acid (TA) by polyvinyl alcohol (PVA)-alginate immobilized Pseudomonas sp. was carried out in a packed-bed reactor. The effect of inlet TA concentration on biodegradation was investigated at 30°C, pH 7 and flow rate of 20 ml/min. The effects of flow rate on mass transfer and biodegradation ...

  2. Synthetic biodegradable functional polymers for tissue engineering: a brief review

    OpenAIRE

    BaoLin, GUO; MA, Peter X.

    2014-01-01

    Scaffolds play a crucial role in tissue engineering. Biodegradable polymers with great processing flexibility are the predominant scaffolding materials. Synthetic biodegradable polymers with well-defined structure and without immunological concerns associated with naturally derived polymers are widely used in tissue engineering. The synthetic biodegradable polymers that are widely used in tissue engineering, including polyesters, polyanhydrides, polyphosphazenes, polyurethane, and poly (glyce...

  3. The studies on waste biodegradation by Tenebrio molitor

    Directory of Open Access Journals (Sweden)

    Bożek Magdalena

    2017-01-01

    Full Text Available As cities are growing in size with a rise in the population, the amount of plastic waste generated is increasing and becoming unmanageable. The treatment and disposal of plastic waste is an urgent need of our present and future. It has been proved recently that mealworms, the larvae of Tenebrio molitor Linnaeus, are able eat styrofoam, a common polystyrene product. Polystyrene is one of the most widely used plastics, the scale of its production being several million tons per year. Tenebrio molitor is one of the largest pests found in stored-grain products. The insect is indigenous to Europe, but is currently cosmopolitan in distribution. The styrofoam is efficiently degraded in the larval gut by microorganisms. We have used the larvae of T. molitor to biodegrade three types of food packaging plastics: polystyrene (PS, polyvinyl chloride (PVC and polylactide (PLA. PVC is a thermoplastic made of 57% chlorine (derived from industrial grade salt and 43% carbon (derived predominantly from oil /gas via ethylene. It is the world's third-most widely produced synthetic plastic polymer, which is not biodegradable easily. On the other hand, PLA is an easily biodegradable and bioactive thermoplastic aliphatic polyester derived from corn and tapioca starch or sugarcane. Three groups of larvae were fed selected types of polymers as an only food, while a control population was fed on oatmeal. The mass loss, dry matter content and biochemical composition of mealworms were assessed in the performed laboratory experiments. The protein concentration in homogenates of the larvae was determined by the Bradford method. To determine the level of hydrolized carbohydrates we used anthrone method. The classical sulfo-phospho-vanillin assay (SPVA was used to quantitate total lipids in mealworms. The results allowed to compare the decomposition efficiency of selected polymer materials by mealworms and to recognize the mechanism of decomposition contributing to the future

  4. Is current training in basic and advanced cardiac life support (BLS & ACLS) effective? A study of BLS & ACLS knowledge amongst healthcare professionals of North-Kerala.

    Science.gov (United States)

    Nambiar, Madavan; Nedungalaparambil, Nisanth Menon; Aslesh, Ottapura Prabhakaran

    2016-01-01

    Healthcare professionals are expected to have knowledge of current basic and advanced cardiac life support (BLS/ACLS) guidelines to revive unresponsive patients. A cross-sectional study was conducted to evaluate the current practices and knowledge of BLS/ACLS principles among healthcare professionals of North-Kerala using pretested self-administered structured questionnaire. Answers were validated in accordance with American Heart Association's BLS/ACLS teaching manual and the results were analysed. Among 461 healthcare professionals, 141 (30.6%) were practicing physicians, 268 (58.1%) were nurses and 52 (11.3%) supporting staff. The maximum achievable score was 20 (BLS 15/ACLS 5). The mean score amongst all healthcare professionals was 8.9±4.7. The mean score among physicians, nurses and support staff were 8.6±3.4, 9±3.6 and 9±3.3 respectively. The majority of healthcare professionals scored ≤50% (237, 51.4%); 204 (44.3%) scored 51%-80% and 20 (4.34%) scored >80%. Mean scores decreased with age, male sex and across occupation. Nurses who underwent BLS/ACLS training previously had significantly higher mean scores (10.2±3.4) than untrained (8.2±3.6, P =0.001). Physicians with <5 years experience ( P =0.002) and nurses in the private sector ( P =0.003) had significantly higher scores. One hundred and sixty three (35.3%) healthcare professionals knew the correct airway opening manoeuvres like head tilt, chin lift and jaw thrust. Only 54 (11.7%) respondents were aware that atropine is not used in ACLS for cardiac arrest resuscitation and 79 (17.1%) correctly opted ventricular fibrillation and pulseless ventricular tachycardia as shockable rhythms. The majority of healthcare professionals (356, 77.2%) suggested that BLS/ACLS be included in academic curriculum. Inadequate knowledge of BLS/ACLS principles amongst healthcare professionals, especially physicians, illuminate lacunae in existing training systems and merit urgent redressal.

  5. Biodegradation of norfloxacin by Penicillium frequentans isolated ...

    African Journals Online (AJOL)

    One norfloxacin-degrading fungi was isolated from soil contaminated by norfloxacin and preliminary identified as Penicillium frequentans. Indoor simulative degradation experiments were carried out to investigate the biodegradation kinetics of norfloxacin with or without NFX3 in soil. The results indicate that the ...

  6. Formulation and characterization of caffeine biodegradable chewing ...

    African Journals Online (AJOL)

    ) is a test for analysing the textural properties of food, in which the samples are ..... Food Technol 1978;. 32: 62-66. 16. Mehta FM, Trivedi P. Formulation and characterization of biodegradable medicated chewing gum delivery system for motion ...

  7. Cobalt-chitosan: Magnetic and biodegradable heterogeneous ...

    Indian Academy of Sciences (India)

    A novel and biodegradable cobalt-chitosan as a magnetic heterogeneous catalyst was synthesized and characterized by XPS, FT-IR, EDX and TEM. Catalytic performance of cobalt- chitosan was tested by aerobic oxidation of alkyl arenes and alcohols. The results show that the catalyst exhibits excellent conversion for ...

  8. Preparation of Natural and Synthetic Porous Biodegradable ...

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Preparation of Natural and Synthetic Porous Biodegradable Scaffolds for Infected Wounds. Characterised for their physical properties, pore size and release kinetics. Release kinetics of bioactive molecules (antibiotics) in a controlled fashion. Release pattern of the ...

  9. Production of Polyhydroxyalkanoates, a bacterial biodegradable ...

    African Journals Online (AJOL)

    ... production has restricted its applications. The possibility of producing this polymer commercially and at comparable cost has been the main focus in this area. Key Words: Polyhydroxyalkanoates, biodegradable polymer, bioplastic, poly(3-hydroxybutyrate), biosynthesis. African Journal of Biotechnology Vol.3(1) 2004: 18- ...

  10. Biodegradable polymers derived from amino acids.

    Science.gov (United States)

    Khan, Wahid; Muthupandian, Saravanan; Farah, Shady; Kumar, Neeraj; Domb, Abraham J

    2011-12-08

    In the past three decades, the use of polymeric materials has increased dramatically for biomedical applications. Many α-amino acids derived biodegradable polymers have also been intensely developed with the main goal to obtain bio-mimicking functional biomaterials. Polymers derived from α-amino acids may offer many advantages, as these polymers: (a) can be modified further to introduce new functions such as imaging, molecular targeting and drugs can be conjugated chemically to these polymers, (b) can improve on better biological properties like cell migration, adhesion and biodegradability, (c) can improve on mechanical and thermal properties and (d) their degradation products are expected to be non-toxic and readily metabolized/excreted from the body. This manuscript focuses on biodegradable polymers derived from natural amino acids, their synthesis, biocompatibility and biomedical applications. It is observed that polymers derived from α-amino acids constitute a promising family of biodegradable materials. These provide innovative multifunctional polymers possessing amino acid side groups with biological activity and with innumerous potential applications. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Biodegradable Shape Memory Polymers in Medicine.

    Science.gov (United States)

    Peterson, Gregory I; Dobrynin, Andrey V; Becker, Matthew L

    2017-11-01

    Shape memory materials have emerged as an important class of materials in medicine due to their ability to change shape in response to a specific stimulus, enabling the simplification of medical procedures, use of minimally invasive techniques, and access to new treatment modalities. Shape memory polymers, in particular, are well suited for such applications given their excellent shape memory performance, tunable materials properties, minimal toxicity, and potential for biodegradation and resorption. This review provides an overview of biodegradable shape memory polymers that have been used in medical applications. The majority of biodegradable shape memory polymers are based on thermally responsive polyesters or polymers that contain hydrolyzable ester linkages. These materials have been targeted for use in applications pertaining to embolization, drug delivery, stents, tissue engineering, and wound closure. The development of biodegradable shape memory polymers with unique properties or responsiveness to novel stimuli has the potential to facilitate the optimization and development of new medical applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Evaluation of biodegradation and biocompatibility of collagen ...

    Indian Academy of Sciences (India)

    The aim of this study was to develop a new variant of membranes based on collagen (COL), chitosan (CHI) and alkaline phosphatase (ALP) immobilized and cross-linking with glutaraldehyde (GA) at different concentrations. The biodegradation in the presence of collagenase was investigated. Biocompatibility was ...

  13. Cobalt-chitosan: Magnetic and biodegradable heterogeneous ...

    Indian Academy of Sciences (India)

    Abstract. A novel and biodegradable cobalt-chitosan as a magnetic heterogeneous catalyst was synthesized and characterized by XPS, FT-IR, EDX and TEM. Catalytic performance of cobalt- chitosan was tested by aerobic oxidation of alkyl arenes and alcohols. The results show that the catalyst exhibits excellent ...

  14. hydrocarbons biodegradation and evidence of mixed petroleum ...

    African Journals Online (AJOL)

    DJFLEX

    mode (EI) at 70Ev ionisation energy and scanned from 50 to 650 dalton. 3.0 Result and discussion. 3.1 n-alkanes and Isoprenoid Hydrocarbons. The concentrations (mgkg-1) ..... community in the Yellowish geothermal environment. Nature 434, 1000-1014. Cross River System. HYDROCARBONS BIODEGRADATION AND ...

  15. Fate and biodegradability of sulfonated aromatic amines

    NARCIS (Netherlands)

    Tan, N.C.G.; Leeuwen, van A.; Voorthuizen, van E.M.; Slenders, P.; Prenafeta, F.X.; Temmink, H.; Lettinga, G.; Field, J.A.

    2005-01-01

    Ten sulfonated aromatic amines were tested for their aerobic and anaerobic biodegradability and toxicity potential in a variety of environmental inocula. Of all the compounds tested, only two aminobenzenesulfonic acid (ABS) isomers, 2- and 4-ABS, were degraded. The observed degradation occurred only

  16. Evaluation of biodegradation and biocompatibility of collagen ...

    Indian Academy of Sciences (India)

    The biodegradation in the presence of collagenase was investigated. Biocompatibility was evaluated by MTT assay using a mouse fibroblast cell culture type NCTC (clone 929). Non-cross-linked samples were biocompatible and membranes cross-linked with low concentrations of GA (0.04, 0.08%) were also iocompatible.

  17. Biodegradability of diesel and biodiesel blends

    African Journals Online (AJOL)

    STORAGESEVER

    2008-05-02

    May 2, 2008 ... The biodegradability of pure diesel and biodiesel and blends with different proportions of biodiesel (2%. (commercial); 5% and 20%) was evaluated employing the respirometric method and the redox indicator. 2,6-dichlorophenol indophenol (DCPIP) test. In the former, experiments simulating the ...

  18. Modeling aerobic biodegradation in the capillary fringe.

    Science.gov (United States)

    Luo, Jian; Kurt, Zohre; Hou, Deyi; Spain, Jim C

    2015-02-03

    Vapor intrusion from volatile subsurface contaminants can be mitigated by aerobic biodegradation. Laboratory column studies with contaminant sources of chlorobenzene and a mixture of chlorobenzene, 1,2-dichlorobenzene, and 1,4-dichlorobenzene showed that contaminants were rapidly degraded in thin reactive zones with high biomass and low substrate concentrations in the vicinity of the capillary fringe. Such behavior was well characterized by a model that includes oxygen-, substrate-, and biomass-dependent biodegradation kinetics along with diffusive transport processes. An analytical solution was derived to provide theoretical support for the simplification of reaction kinetics and the approximation of reactive zone location and mass flux relationships at steady state. Results demonstrate the potential of aerobic natural attenuation in the capillary fringe for preventing contaminant migration in the unsaturated zone. The solution indicates that increasing contaminant mass flux into the column creates a thinner reactive zone and pushes it toward the oxygen boundary, resulting in a shorter distance to the oxygen source and a larger oxygen mass flux that balances the contaminant mass flux. As a consequence, the aerobic biodegradation can reduce high contaminant concentrations to low levels within the capillary fringe and unsaturated zone. The results are consistent with the observations of thin reactive layers at the interface in unsaturated zones. The model considers biomass while including biodegradation in the capillary fringe and unsaturated zone and clearly demonstrates that microbial communities capable of using the contaminants as electron donors may lead to instantaneous degradation kinetics in the capillary fringe and unsaturated zone.

  19. Diisopropanolamine biodegradation potential at sour gas plants

    Energy Technology Data Exchange (ETDEWEB)

    Gieg, L.M.; Greene, E.A.; Coy, D.L.; Fedorak, P.M.

    1998-12-31

    The potential for aerobic and anaerobic biodegradation of a sour gas treatment chemical, diisopropanolamine (DIPA), was studied using contaminated aquifer materials from three sour gas treatment sites in western Canada. DIPA was found to be readily consumed under aerobic conditions at 8 C and 28 C in shake flask cultures incubated with aquifer material from each of the sites, and this removal was characterized by first-order kinetics. In addition, DIPA biodegradation was found to occur under nitrate-, Mn(IV)-, and Fe(III)-reducing conditions at 28 C, and in some cases at 8 C, in laboratory microcosms. DIPA loss corresponded to consumption of nitrate, and production of Mn(II) and Fe(II) in viable microcosms compared to corresponding sterile controls. A threshold DIPA concentration near 40 mg/L was observed in the anaerobic microcosms. This report provides the first evidence that DIPA is biodegraded under anaerobic conditions, and the data suggest that biodegradation may contribute to DIPA attenuation under aerobic and anaerobic conditions in aquifers contaminated with this sour gas treatment chemical.

  20. Biodegradable poly (lactic acid) microspheres containing total ...

    Indian Academy of Sciences (India)

    The fabrication of biodegradable poly(lactic acid) (PLA) microspheres containing total alkaloids of Caulis sinomenii was investigated. The formation, diameter, morphology and properties of the microspheres were characterized using Fourier transform infrared spectroscopy (FT–IR), laser particle size analyser and scanning ...

  1. Biodegradation of chlorobenzoic acids by ligninolytic fungi

    Czech Academy of Sciences Publication Activity Database

    Muzikář, Milan; Křesinová, Zdena; Svobodová, Kateřina; Filipová, Alena; Čvančarová, Monika; Cajthamlová, Kamila; Cajthaml, Tomáš

    2011-01-01

    Roč. 196, - (2011), s. 386-394 ISSN 0304-3894 R&D Projects: GA MŠk 2B06156; GA ČR GA525/09/1058 Institutional research plan: CEZ:AV0Z50200510 Keywords : Chlorobenzoic acid * Polychlorinated biphenyls * Biodegradation Subject RIV: EE - Microbiology, Virology Impact factor: 4.173, year: 2011

  2. Cobalt-chitosan: Magnetic and biodegradable heterogeneous ...

    Indian Academy of Sciences (India)

    Cobalt-chitosan: Magnetic and biodegradable catalyst. 1931. Table 3. Effects of the solvent, temperature and base on oxidation of phenylethyl alcohol using cobalt-chitosan.a. Entry. Solvent. Temperature. Base. Yield (%) b. 1. DMF. 100. K2CO3. 60. 2. DMF. 100. KOH. 60. 3. CH3CN. 80. K2CO3. 65. 4. H2O reflux. KOH. 10. 5.

  3. Biodegradation of synthetic detergents in wastewater

    African Journals Online (AJOL)

    STORAGESEVER

    2009-03-20

    Mar 20, 2009 ... Surfactants constitute a major ingredient of detergent components. Usually surfactants are disposed after use to sewage treatment plants (STPs). Here, biodegradation processes and adsorption on sludge particles remove these chemicals from wastewaters to a greater or lesser extent, depending on the ...

  4. Polyvinyl alcohol biodegradation under denitrifying conditions

    Czech Academy of Sciences Publication Activity Database

    Marušincová, H.; Husárová, L.; Růžička, J.; Ingr, M.; Navrátil, Václav; Buňková, L.; Koutný, M.

    2013-01-01

    Roč. 84, October (2013), s. 21-28 ISSN 0964-8305 Grant - others:GA ČR(CZ) GAP108/10/0200 Institutional support: RVO:61388963 Keywords : polyvinyl alcohol * biodegradation * denitrification * waste-water treatment * anaerobic * Steroidobacter Subject RIV: EI - Biotechnology ; Bionics Impact factor: 2.235, year: 2013

  5. Biodegradable polymersomes for targeted ultrasound imaging

    NARCIS (Netherlands)

    Zhou, W.; Hennink, W.E.; Feijen, J.; Meng, Fenghua; Sam, T; Engbers, G.H.M.; Feijen, Jan

    2006-01-01

    Biodegradable polymersomes with a sub-micron size were prepared by using poly(ethylene glycol)–polylactide (PEG–PDLLA) block-copolymers in aqueous media. Air-encapsulated polymersomes could be obtained by a lyophilization/rehydration procedure. Preliminary results showed that these polymersomes were

  6. Characteristics of electricity generation and biodegradation in tidal river sludge-used microbial fuel cells.

    Science.gov (United States)

    Touch, Narong; Hibino, Tadashi; Nagatsu, Yoshiyuki; Tachiuchi, Kouhei

    2014-04-01

    The electricity generation behavior of microbial fuel cell (MFC) using the sludge collected from the riverbank of a tidal river, and the biodegradation of the sludge by the electricity generation are evaluated. Although the maximum current density (150-300 mA/m(2)) was higher than that of MFC using freshwater sediment (30 mA/m(2)), the output current was greatly restricted by the mass transfer limitation. However, our results also indicate that placing the anode in different locations in the sludge could reduce the mass transfer limitation. After approximately 3 months, the removal efficiency of organic carbon was approximately 10%, demonstrated that MFC could also enhance the biodegradation of the sludge by nearly 10-fold comparing with the natural biodegradation. We also found that the biodegradation could be identified by the behavior of oxygen consumption of the sludge. Importantly, the oxygen consumption of the sludge became higher along with the electricity generation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. The toxicity of oil-contaminated muskeg following biodegradation

    International Nuclear Information System (INIS)

    Farwell, A.; Kelly-Hooper, F.; McAlear, J.; Sinnesael, K.; Dixon, D.

    2009-01-01

    The current environmental criteria for the maximum allowable levels of hydrocarbons resulting from an oil spill assume that all detectable hydrocarbons are petroleum hydrocarbons (PHC) and do not account for naturally-occurring biogenic hydrocarbons (BHC). As such, some soils may be wrongfully assessed as being PHC contaminated. A false identification could lead to unnecessary and costly bioremediation that is potentially disruptive to functioning ecosystems. This study is part of a larger project to differentiate between natural and petroleum F3 hydrocarbons in muskeg material that has been impacted by an oil spill. The toxicity of oil-contaminated muskeg was examined following biodegradation in laboratory microcosms. Preliminary acute toxicity tests using locally purchased Sphagnum peat moss contaminated with Federated Crude oil had no effect on the survival of earthworms (Eisenia andrei), but springtails (Orthonychiurus folsomi) were more sensitive. Earthworm and springtail reproduction bioassays and a Northern wheatgrass (Elymus lanceolatus) growth bioassay was used to test the crude-oil-contaminated peat. All 3 test species will be used to test for reduced toxicity following biodegradation of Federated Crude oil-contaminated muskeg from northern Alberta under simulated conditions.

  8. The toxicity of oil-contaminated muskeg following biodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Farwell, A.; Kelly-Hooper, F.; McAlear, J.; Sinnesael, K.; Dixon, D. [Waterloo Univ., Waterloo, ON (Canada)

    2009-07-01

    The current environmental criteria for the maximum allowable levels of hydrocarbons resulting from an oil spill assume that all detectable hydrocarbons are petroleum hydrocarbons (PHC) and do not account for naturally-occurring biogenic hydrocarbons (BHC). As such, some soils may be wrongfully assessed as being PHC contaminated. A false identification could lead to unnecessary and costly bioremediation that is potentially disruptive to functioning ecosystems. This study is part of a larger project to differentiate between natural and petroleum F3 hydrocarbons in muskeg material that has been impacted by an oil spill. The toxicity of oil-contaminated muskeg was examined following biodegradation in laboratory microcosms. Preliminary acute toxicity tests using locally purchased Sphagnum peat moss contaminated with Federated Crude oil had no effect on the survival of earthworms (Eisenia andrei), but springtails (Orthonychiurus folsomi) were more sensitive. Earthworm and springtail reproduction bioassays and a Northern wheatgrass (Elymus lanceolatus) growth bioassay was used to test the crude-oil-contaminated peat. All 3 test species will be used to test for reduced toxicity following biodegradation of Federated Crude oil-contaminated muskeg from northern Alberta under simulated conditions.

  9. Tissue Equivalents Based on Cell-Seeded Biodegradable Microfluidic Constructs

    Directory of Open Access Journals (Sweden)

    Sarah L. Tao

    2010-03-01

    Full Text Available One of the principal challenges in the field of tissue engineering and regenerative medicine is the formation of functional microvascular networks capable of sustaining tissue constructs. Complex tissues and vital organs require a means to support oxygen and nutrient transport during the development of constructs both prior to and after host integration, and current approaches have not demonstrated robust solutions to this challenge. Here, we present a technology platform encompassing the design, construction, cell seeding and functional evaluation of tissue equivalents for wound healing and other clinical applications. These tissue equivalents are comprised of biodegradable microfluidic scaffolds lined with microvascular cells and designed to replicate microenvironmental cues necessary to generate and sustain cell populations to replace dermal and/or epidermal tissues lost due to trauma or disease. Initial results demonstrate that these biodegradable microfluidic devices promote cell adherence and support basic cell functions. These systems represent a promising pathway towards highly integrated three-dimensional engineered tissue constructs for a wide range of clinical applications.

  10. Biodegradation of Ochratoxin A for Food and Feed Decontamination

    Directory of Open Access Journals (Sweden)

    Luís Abrunhosa

    2010-05-01

    Full Text Available Ochratoxin A (OTA is one of the most important mycotoxins that is found in food and feed products. It has proven toxic properties, being primarily known for its nephrotoxicity and carcinogenicity to certain animal species. OTA is produced by several species of Aspergillus and Penicillium that can be found in a wide variety of agricultural products, which makes the presence of OTA in these products common. Many countries have statutory limits for OTA, and concentrations need to be reduced to as low as technologically possible in food and feed. The most important measures to be taken to control OTA are preventive in order to avoid fungal growth and OTA production. However, these measures are difficult to implement in all cases with the consequence of OTA remaining in agricultural commodities. Remediation processes are often used to eliminate, reduce or avoid the toxic effects of OTA. Biological methods have been considered increasingly as an alternative to physical and chemical treatments. However, examples of practical applications are infrequent. This review will focus on the (i known microorganisms and enzymes that are able to biodegrade OTA; (ii mode of action of biodegradation and (iii current applications. A critical discussion about the technical applicability of these strategies is presented.

  11. Biodegradation of phytosanitary products in biological wastewater treatment.

    Science.gov (United States)

    Massot, A; Estève, K; Noilet, P; Méoule, C; Poupot, C; Mietton-Peuchot, M

    2012-04-15

    Agricultural activity generates two types of waste: firstly, biodegradable organic effluents generally treated by biological processes and, secondly, phytosanitary effluents which contain residues of plant protection products. The latter are collected and treated. Current technological solutions are essentially based on concentration or physical-chemical processes. However, recent improvements in the biodegradability of pesticides open the way to the consideration of alternative, biological, treatment using mixed liquor from wastewater plant activated sludge. The feasibility of the biological treatment of viticultural effluents has been evaluated by the application of pesticides to activated sludge. The necessity for selection of a pesticide-resistant biomass has been highlighted. The elimination of the phytosanitary products shows the potential of a resistant biomass in the treatment of pesticides. The aerated biological storage ponds at three wineries, followed by a sand or reed-bed filter, were used for the treatment of the total annual volume of the viticulture effluents and validate the laboratory experiments. The results show that the biological purification of pesticides by activated sludge is possible by allowing approximately 8 days for biomass adaptation. Stability of purification occurs between 20 and 30 days. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Improving the biodegradative capacity of subsurface bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Romine, M.F.; Brockman, F.J.

    1993-04-01

    The continual release of large volumes of synthetic materials into the environment by agricultural and industrial sources over the last few decades has resulted in pollution of the subsurface environment. Cleanup has been difficult because of the relative inaccessibility of the contaminants caused by their wide dispersal in the deep subsurface, often at low concentrations and in large volumes. As a possible solution for these problems, interest in the introduction of biodegradative bacteria for in situ remediation of these sites has increased greatly in recent years (Timmis et al. 1988). Selection of biodegradative microbes to apply in such cleanup is limited to those strains that can survive among the native bacterial and predator community members at the particular pH, temperature, and moisture status of the site (Alexander, 1984). The use of microorganisms isolated from subsurface environments would be advantageous because the organisms are already adapted to the subsurface conditions. The options are further narrowed to strains that are able to degrade the contaminant rapidly, even in the presence of highly recalcitrant anthropogenic waste mixtures, and in conditions that do not require addition of further toxic compounds for the expression of the biodegradative capacity (Sayler et al. 1990). These obstacles can be overcome by placing the genes of well-characterized biodegradative enzymes under the control of promoters that can be regulated by inexpensive and nontoxic external factors and then moving the new genetic constructs into diverse groups of subsurface microbes. ne objective of this research is to test this hypothesis by comparing expression of two different toluene biodegradative enzymatic pathways from two different regulatable promoters in a variety of subsurface isolates.

  13. Improving the biodegradative capacity of subsurface bacteria

    International Nuclear Information System (INIS)

    Romine, M.F.; Brockman, F.J.

    1993-04-01

    The continual release of large volumes of synthetic materials into the environment by agricultural and industrial sources over the last few decades has resulted in pollution of the subsurface environment. Cleanup has been difficult because of the relative inaccessibility of the contaminants caused by their wide dispersal in the deep subsurface, often at low concentrations and in large volumes. As a possible solution for these problems, interest in the introduction of biodegradative bacteria for in situ remediation of these sites has increased greatly in recent years (Timmis et al. 1988). Selection of biodegradative microbes to apply in such cleanup is limited to those strains that can survive among the native bacterial and predator community members at the particular pH, temperature, and moisture status of the site (Alexander, 1984). The use of microorganisms isolated from subsurface environments would be advantageous because the organisms are already adapted to the subsurface conditions. The options are further narrowed to strains that are able to degrade the contaminant rapidly, even in the presence of highly recalcitrant anthropogenic waste mixtures, and in conditions that do not require addition of further toxic compounds for the expression of the biodegradative capacity (Sayler et al. 1990). These obstacles can be overcome by placing the genes of well-characterized biodegradative enzymes under the control of promoters that can be regulated by inexpensive and nontoxic external factors and then moving the new genetic constructs into diverse groups of subsurface microbes. ne objective of this research is to test this hypothesis by comparing expression of two different toluene biodegradative enzymatic pathways from two different regulatable promoters in a variety of subsurface isolates

  14. Hydrocarbons biodegradation in unsaturated porous medium

    International Nuclear Information System (INIS)

    Gautier, C.

    2007-12-01

    Biological processes are expected to play an important role in the degradation of petroleum hydrocarbons in contaminated soils. However, factors influencing the kinetics of biodegradation are still not well known, especially in the unsaturated zone. To address these biodegradation questions in the unsaturated zone an innovative experimental set up based on a physical column model was developed. This experimental set up appeared to be an excellent tool for elaboration of a structured porous medium, with well defined porous network and adjusted water/oil saturations. Homogeneous repartition of both liquid phases (i.e., aqueous and non aqueous) in the soil pores, which also contain air, was achieved using ceramic membranes placed at the bottom of the soil column. Reproducible interfaces (and connectivity) are developed between gas, and both non mobile water and NAPL phases, depending on the above-defined characteristics of the porous media and on the partial saturations of these three phases (NAPL, water and gas). A respirometric apparatus was coupled to the column. Such experimental set up have been validated with hexadecane in dilution in an HMN phase. This approach allowed detailed information concerning n-hexadecane biodegradation, in aerobic condition, through the profile of the oxygen consumption rate. We have taken benefit of this technique, varying experimental conditions, to determine the main parameters influencing the biodegradation kinetics and compositional evolution of hydrocarbons, under steady state unsaturated conditions and with respect to aerobic metabolism. Impacts of the nitrogen quantity and of three different grain sizes have been examined. Biodegradation of petroleum cut, as diesel cut and middle distillate without aromatic fraction, were, also studied. (author)

  15. Advanced Approaches to Greatly Reduce Hydrogen Gas Crossover Losses in PEM Electrolyzers Operating at High Pressures and Low Current Densities, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ElectroChem proposes technology advances in its unique PEM IFF water electrolyzer design to meet the NASA requirement for an electrolyzer that will operate very...

  16. Advanced Approaches to Greatly Reduce Hydrogen Gas Crossover Losses in PEM Electrolyzers Operating at High Pressures and Low Current Densities Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ElectroChem proposes technology advances in its unique PEM IFF water electrolyzer design to meet the NASA requirement for an electrolyzer that will operate very...

  17. Advanced Approaches to Greatly Reduce Hydrogen Gas Crossover Losses in PEM Electrolyzers Operating at High Pressures and Low Current Densities, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — ElectroChem proposes a Phase II program to advance its very successful SBIR Phase I technology effort to the point of minimum hydrogen loss through the electrolyzer...

  18. Detecting Intracranial Hemorrhage Using Automatic Tube Current Modulation With Advanced Modeled Iterative Reconstruction in Unenhanced Head Single- and Dual-Energy Dual-Source CT.

    Science.gov (United States)

    Scholtz, Jan-Erik; Wichmann, Julian L; Bennett, Dennis W; Leithner, Doris; Bauer, Ralf W; Vogl, Thomas J; Bodelle, Boris

    2017-05-01

    The purpose of our study was to determine diagnostic accuracy, image quality, and radiation dose of low-dose single- and dual-energy unenhanced third-generation dual-source head CT for detection of intracranial hemorrhage (ICH). A total of 123 patients with suspected ICH were examined using a dual-source 192-MDCT scanner. Standard-dose 120-kVp single-energy CT (SECT; n = 36) and 80-kVp and 150-kVp dual-energy CT (DECT; n = 30) images were compared with low-dose SECT (n = 32) and DECT (n = 25) images obtained using automated tube current modulation (ATCM). Advanced modeled iterative reconstruction (ADMIRE) was used for all protocols. Detection of ICH was performed by three readers who were blinded to the image acquisition parameters of each image series. Image quality was assessed both quantitatively and qualitatively. Interobserver agreement was calculated using the Fleiss kappa. Radiation dose was measured as dose-length product (DLP). Detection of ICH was excellent (sensitivity, 94.9-100%; specificity, 94.7-100%) in all protocols (p = 1.00) with perfect interobserver agreement (0.83-0.96). Qualitative ratings showed significantly better ratings for both standard-dose protocols regarding gray matter-to-white matter contrast (p ≤ 0.014), whereas highest gray matter-to-white matter contrast-to-noise ratio was observed with low-dose DECT images (p ≥ 0.057). The lowest posterior fossa artifact index was measured for standard-dose DECT, which showed significantly lower values compared with low-dose protocols (p ≤ 0.034). Delineation of ventricular margins and sharpness of subarachnoidal spaces were rated excellent in all protocols (p ≥ 0.096). Low-dose techniques lowered radiation dose by 26% for SECT images (DLP, 575.0 ± 72.3 mGy · cm vs 771.5 ± 146.8 mGy · cm; p dual-source CT while allowing significant radiation dose reduction.

  19. Advance Health Care Directives and “Public Guardian”: The Italian Supreme Court Requests the Status of Current and Not Future Inability

    Directory of Open Access Journals (Sweden)

    Francesco Paolo Busardò

    2014-01-01

    Full Text Available Advance health care decisions animate an intense debate in several European countries, which started more than 20 years ago in the USA and led to the adoption of different rules, based on the diverse legal, sociocultural and philosophical traditions of each society. In Italy, the controversial issue of advance directives and end of life’s rights, in the absence of a clear and comprehensive legislation, has been over time a subject of interest of the Supreme Court. Since 2004 a law introduced the “Public Guardian,” aiming to provide an instrument of assistance to the person lacking in autonomy because of an illness or incapacity. Recently, this critical issue has once again been brought to the interest of the Supreme Court, which passed a judgment trying to clarify the legislative application of the appointment of the Guardian in the field of advance directives.

  20. Biodegradable bioplastics from food wastes

    Science.gov (United States)

    An estimated 1.8 billion tons of waste are created annually from food processing in the US, including the peels, pulp, and pomace (PPP) generated from fruits and vegetables when they are converted into frozen or canned products or pressed into juice. PPP currently is sold as animal feed at low cost,...

  1. Lignin biodegradation and industrial implications

    Directory of Open Access Journals (Sweden)

    Adam B Fisher

    2014-12-01

    Full Text Available Lignocellulose, which comprises the cell walls of plants, is the Earth’s most abundant renewable source of convertible biomass. However, in order to access the fermentable sugars of the cellulose and hemicellulose fraction, the extremely recalcitrant lignin heteropolymer must be hydrolyzed and removed—usually by harsh, costly thermochemical pretreatments. Biological processes for depolymerizing and metabolizing lignin present an opportunity to improve the overall economics of the lignocellulosic biorefinery by facilitating pretreatment, improving downstream cellulosic fermentations or even producing a valuable effluent stream of aromatic compounds for creating value-added products. In the following review we discuss background on lignin, the enzymology of lignin degradation, and characterized catabolic pathways for metabolizing the by-products of lignin degradation. To conclude we survey advances in approaches to identify novel lignin degrading phenotypes and applications of these phenotypes in the lignocellulosic bioprocess.

  2. Biodegradable magnesium nanoparticle-enhanced laser hyperthermia therapy

    Directory of Open Access Journals (Sweden)

    Wang Q

    2012-08-01

    Full Text Available Qian Wang,1 Liping Xie,1 Zhizhu He,2 Derui Di,2 Jing Liu1,21Department of Biomedical Engineering, School of Medicine, Tsinghua University, 2Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, People's Republic of ChinaBackground: Recently, nanoparticles have been demonstrated to have tremendous merit in terms of improving the treatment specificity and thermal ablation effect on tumors. However, the potential toxicity and long-term side effects caused by the introduced nanoparticles and by expelling them out of the body following surgery remain a significant challenge. Here, we propose for the first time to directly adopt magnesium nanoparticles as the heating enhancer in laser thermal ablation to avoid these problems by making full use of the perfect biodegradable properties of this specific material.Methods: To better understand the new nano “green” hyperthermia modality, we evaluated the effects of magnesium nanoparticles on the temperature transients inside the human body subject to laser interstitial heating. Further, we experimentally investigated the heating enhancement effects of magnesium nanoparticles on a group of biological samples: oil, egg white, egg yolk, in vitro pig tissues, and the in vivo hind leg of rabbit when subjected to laser irradiation.Results: Both the theoretical simulations and experimental measurements demonstrated that the target tissues injected with magnesium nanoparticles reached much higher temperatures than tissues without magnesium nanoparticles. This revealed the enhancing behavior of the new nanohyperthermia method.Conclusion: Given the unique features of magnesium nanoparticles – their complete biological safety and ability to enhance heating – which most other advanced metal nanoparticles do not possess, the use of magnesium nanoparticles in hyperthermia therapy offers an important “green” nanomedicine modality for treating tumors

  3. Soil slurry reactors for the assessment of contaminant biodegradation

    Science.gov (United States)

    Toscano, G.; Colarieti, M. L.; Greco, G.

    2012-04-01

    Slurry reactors are frequently used in the assessment of feasibility of biodegradation in natural soil systems. The rate of contaminant removal is usually quantified by zero- or first-order kinetics decay constants. The significance of such constants for the evaluation of removal rate in the field could be questioned because the slurry reactor is a water-saturated, well-stirred system without resemblance with an unsaturated fixed bed of soil. Nevertheless, a kinetic study with soil slurry reactors can still be useful by means of only slightly more sophisticated kinetic models than zero-/first-order decay. The use of kinetic models taking into account the role of degrading biomass, even in the absence of reliable experimental methods for its quantification, provides further insight into the effect of nutrient additions. A real acceleration of biodegradation processes is obtained only when the degrading biomass is in the growth condition. The apparent change in contaminant removal course can be useful to diagnose biomass growth without direct biomass measurement. Even though molecular biology techniques are effective to assess the presence of potentially degrading microorganism in a "viable-but-nonculturable" state, the attainment of conditions for growth is still important to the development of enhanced remediation techniques. The methodology is illustrated with reference to data gathered for two test sites, Oslo airport Gardermoen in Norway (continuous contamination by aircraft deicing fluids) and the Trecate site in Italy (aged contamination by crude oil spill). This research is part of SoilCAM project (Soil Contamination, Advanced integrated characterisation and time-lapse Monitoring 2008-2012, EU-FP7).

  4. Biodegradable polymers as encapsulation materials for cosmetics and personal care markets.

    Science.gov (United States)

    Ammala, Anne

    2013-04-01

    The topical and transdermal delivery of active cosmetic ingredients requires safe and non-toxic means of reaching the target sites without causing any irritation. Preservation of the active ingredients is also essential during formulation, storage and application of the final product. As many biologically active substances are not stable and sensitive to temperature, pH, light and oxidation, they require encapsulation to protect against unwanted degradation and also to target specific and controlled release of the active substance. The use of biodegradable polymers as encapsulation materials offers several advantages over other carrier materials. Encapsulation of active ingredients using biodegradable polymeric carriers can facilitate increased efficacy and bioavailability and they are also removed from the body via normal metabolic pathways. This article reviews current research on biodegradable polymers as carrier or encapsulation materials for cosmetic and personal care applications. Some of the challenges and limitations are also discussed. Examples of biodegradable polymers reviewed include polysaccharides, poly α-esters, polyalkylcyanoacrylates and polyamidoamine dendrimers. © 2012 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  5. Nanocomposites of Polyacrylic Acid Nanogels and Biodegradable Polyhydroxybutyrate for Bone Regeneration and Drug Delivery

    Directory of Open Access Journals (Sweden)

    Mikael Larsson

    2014-01-01

    Full Text Available Biodegradable cell scaffolds and local drug delivery to stimulate cell response are currently receiving much scientific attention. Here we present a nanocomposite that combines biodegradation with controlled release of lithium, which is known to enhance bone growth. Nanogels of lithium neutralized polyacrylic acid were synthesized by microemulsion-templated polymerization and were incorporated into a biodegradable polyhydroxybutyrate (PHB matrix. Nanogel size was characterized using dynamic light scattering, and the nanocomposites were characterized with regard to structure using scanning electron microscopy, mechanical properties using tensile testing, permeability using tritiated water, and lithium release in PBS using a lithium specific electrode. The nanogels were well dispersed in the composites and the mechanical properties were good, with a decrease in elastic modulus being compensated by increased tolerance to strain in the wet state. Approximately half of the lithium was released over about three hours, with the remaining fraction being trapped in the PHB for subsequent slow release during biodegradation. The prepared nanocomposites seem promising for use as dual functional scaffolds for bone regeneration. Here lithium ions were chosen as model drug, but the nanogels could potentially act as carriers for larger and more complex drugs, possibly while still carrying lithium.

  6. Biodegradation of Volatile Organic Compounds and Their Effects on Biodegradability under Co-Existing Conditions

    Science.gov (United States)

    Yoshikawa, Miho; Zhang, Ming; Toyota, Koki

    2017-01-01

    Volatile organic compounds (VOCs) are major pollutants that are found in contaminated sites, particularly in developed countries such as Japan. Various microorganisms that degrade individual VOCs have been reported, and genomic information related to their phylogenetic classification and VOC-degrading enzymes is available. However, the biodegradation of multiple VOCs remains a challenging issue. Practical sites, such as chemical factories, research facilities, and illegal dumping sites, are often contaminated with multiple VOCs. In order to investigate the potential of biodegrading multiple VOCs, we initially reviewed the biodegradation of individual VOCs. VOCs include chlorinated ethenes (tetrachloroethene, trichloroethene, dichloroethene, and vinyl chloride), BTEX (benzene, toluene, ethylbenzene, and xylene), and chlorinated methanes (carbon tetrachloride, chloroform, and dichloromethane). We also summarized essential information on the biodegradation of each kind of VOC under aerobic and anaerobic conditions, together with the microorganisms that are involved in VOC-degrading pathways. Interactions among multiple VOCs were then discussed based on concrete examples. Under conditions in which multiple VOCs co-exist, the biodegradation of a VOC may be constrained, enhanced, and/or unaffected by other compounds. Co-metabolism may enhance the degradation of other VOCs. In contrast, constraints are imposed by the toxicity of co-existing VOCs and their by-products, catabolite repression, or competition between VOC-degrading enzymes. This review provides fundamental, but systematic information for designing strategies for the bioremediation of multiple VOCs, as well as information on the role of key microorganisms that degrade VOCs. PMID:28904262

  7. Biodegradation of Volatile Organic Compounds and Their Effects on Biodegradability under Co-Existing Conditions.

    Science.gov (United States)

    Yoshikawa, Miho; Zhang, Ming; Toyota, Koki

    2017-09-27

    Volatile organic compounds (VOCs) are major pollutants that are found in contaminated sites, particularly in developed countries such as Japan. Various microorganisms that degrade individual VOCs have been reported, and genomic information related to their phylogenetic classification and VOC-degrading enzymes is available. However, the biodegradation of multiple VOCs remains a challenging issue. Practical sites, such as chemical factories, research facilities, and illegal dumping sites, are often contaminated with multiple VOCs. In order to investigate the potential of biodegrading multiple VOCs, we initially reviewed the biodegradation of individual VOCs. VOCs include chlorinated ethenes (tetrachloroethene, trichloroethene, dichloroethene, and vinyl chloride), BTEX (benzene, toluene, ethylbenzene, and xylene), and chlorinated methanes (carbon tetrachloride, chloroform, and dichloromethane). We also summarized essential information on the biodegradation of each kind of VOC under aerobic and anaerobic conditions, together with the microorganisms that are involved in VOC-degrading pathways. Interactions among multiple VOCs were then discussed based on concrete examples. Under conditions in which multiple VOCs co-exist, the biodegradation of a VOC may be constrained, enhanced, and/or unaffected by other compounds. Co-metabolism may enhance the degradation of other VOCs. In contrast, constraints are imposed by the toxicity of co-existing VOCs and their by-products, catabolite repression, or competition between VOC-degrading enzymes. This review provides fundamental, but systematic information for designing strategies for the bioremediation of multiple VOCs, as well as information on the role of key microorganisms that degrade VOCs.

  8. Research of the biodegradability of degradable/biodegradable plastic material in various types of environments

    Directory of Open Access Journals (Sweden)

    Dana Adamcová

    2017-04-01

    Full Text Available Research was carried out in order to assess biodegradability of degradable/biodegradable materials made of HDPE and mixed with totally degradable plastic additive (TDPA additive or made of polyethylene (PE with the addition of pro-oxidant additive (d2w additive, advertised as 100% degradable or certifi ed as compostable within various types of environments. Research conditions were: (i controlled composting environment – laboratory-scale, (ii real composting conditions – domestic compost bin, (iii real composting conditions – industrial composting plant and (iv landfill conditions. The results demonstrate that the materials made of HDPE and mixed with totally degradable plastic additive (TDPA additive or made of polyethylene (PE with the addition of pro-oxidant additive (d2w additive or advertised as 100% degradable did not biodegrade in any of the above-described conditions and remained completely intact at the end of the tests. Biodegradation of the certified compostable plastic bags proceeded very well in laboratory-scale conditions and in real composting conditions – industrial composting plant, however, these materials did not biodegrade in real composting conditions – domestic compost bin and landfill conditions.

  9. Nanoparticles from Degradation of Biodegradable Plastic Mulch

    Science.gov (United States)

    Flury, Markus; Sintim, Henry; Bary, Andy; English, Marie; Schaefer, Sean

    2017-04-01

    Plastic mulch films are commonly used in crop production. They provide multiple benefits, including control of weeds and insects, increase of soil and air temperature, reduction of evaporation, and prevention of soil erosion. The use of plastic mulch film in agriculture has great potential to increase food production and security. Plastic mulch films must be retrieved and disposed after usage. Biodegradable plastic mulch films, who can be tilled into the soil after usage offer great benefits as alternative to conventional polyethylene plastic. However, it has to be shown that the degradation of these mulches is complete and no micro- and nanoparticles are released during degradation. We conducted a field experiment with biodegradable mulches and tested mulch degradation. Mulch was removed from the field after the growing season and composted to facilitate degradation. We found that micro- and nanoparticles were released during degradation of the mulch films in compost. This raises concerns about degradation in soils as well.

  10. Modeling ready biodegradability of fragrance materials.

    Science.gov (United States)

    Ceriani, Lidia; Papa, Ester; Kovarich, Simona; Boethling, Robert; Gramatica, Paola

    2015-06-01

    In the present study, quantitative structure activity relationships were developed for predicting ready biodegradability of approximately 200 heterogeneous fragrance materials. Two classification methods, classification and regression tree (CART) and k-nearest neighbors (kNN), were applied to perform the modeling. The models were validated with multiple external prediction sets, and the structural applicability domain was verified by the leverage approach. The best models had good sensitivity (internal ≥80%; external ≥68%), specificity (internal ≥80%; external 73%), and overall accuracy (≥75%). Results from the comparison with BIOWIN global models, based on group contribution method, show that specific models developed in the present study perform better in prediction than BIOWIN6, in particular for the correct classification of not readily biodegradable fragrance materials. © 2015 SETAC.

  11. Current advances in mechanical design and production VII: proceedings of the Seventh Cairo University International MDP Conference ; Cairo-Egypt, February 15-17, 2000

    National Research Council Canada - National Science Library

    Megahed, Säıd M; Hassan, Mohamed F

    2000-01-01

    ... with keynote papers to enrich the sessions and to highlight the recent advances on the various fields of mechanical design and production. A total of 160 papers were submitted to MDP-7 conference from more than 21 countries from the 6 continents. All papers were thoroughly refereed by the conference scientific committee. Following the reviewing proces...

  12. Enhanced biodegradation of polyaromatic hydrocarbons in manufactured gas plant wastes

    International Nuclear Information System (INIS)

    Gauger, W.K.; Srivastava, V.J.; Hayes, T.D.; Linz, D.G.

    1990-01-01

    Scientists at the Institute of Gas Technology (IGT) have focused on enhancing destruction of polyaromatic hydrocarbons (PAHs) present as pollutants in manufactured gas plant (MGP) soils. The factor that bears the most restrictive influence on successful biological PAH degradation is low pollutant transfer from soil into an aqueous environment where biotreatment processes can take place. Physical and chemical enhancements were used in conjunction with biological processes. Physical enhancements overcame the mass transfer problem and made possible the biological destruction of aromatic hydrocarbons. One- to three-ring aromatic hydrocarbons were readily biodegraded in liquid, soil slurry, and -- to a lesser degree -- composted soil systems. Four- to six-ring PAHs remained persistent but were effectively destroyed when chemical co-treatments were used. Combined biological/chemical/physical processes are currently being tested to achieve the most extensive PAH degradation possible for MGP soils. 8 refs., 9 figs., 2 tabs

  13. Biodegradation and Transformation of Nitroaromatic Compounds (POSTPRINT)

    Science.gov (United States)

    2012-07-01

    From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT... MAR -1997 Biodegradation and Transformation of Nitroaromatic Compounds (POSTPRINT) 1900B56A Nishino, Shirley F.; Spain, Jim C. Armstrong Laboratory...space to accommodate bulk matter, and con· cainment of leachates. Generally, not more than 10% of the composting pile can be contaminate d soil (66

  14. Biodegradation of PCDDs/PCDFs and PCBs

    OpenAIRE

    Urbaniak, Magdalena

    2013-01-01

    Rozdział 4 książki Biodegradation - Engineering and Technology Edited by Rolando Chamy and Francisca Rosenkranz • “Innovative resources and effective methods of safety improvement and durability of buildings and transport infrastructure in the sustainable development” financed by the European Union, from the European Fund of Regional Development based on the Operational Programme of the Innovative Economy, POIG.01.01.02-10-106/09

  15. Methotrexate-loaded biodegradable nanoparticles: preparation ...

    Indian Academy of Sciences (India)

    Administrator

    effects as well as to achieve anticipated sustained release properties. In recent years, biodegradable polymeric ... 8 h and lyophilized with vacuum pressure of < 50 mTorr and at a temperature of –40 °C for 48 h. ... out in dialysis tubing using phosphate buffer pH 6∙8 at. 37 ± 0∙5 °C and at 50 rpm. In vitro drug release was.

  16. Biodegradation of ion-exchange media

    International Nuclear Information System (INIS)

    Bowerman, B.S.; Clinton, J.H.; Cowdery, S.R.

    1988-08-01

    Ion-exchange media, both bead resins and powdered filter media, are used in nuclear power plants to remove radioactivity from process water prior to reuse or environmental discharge. Since the ion- exchange media are made from synthetic hydrocarbon-based polymers, they may be susceptible to damage from biological activity. The purpose of this study was to investigate some of the more basic aspects of biodegradation of ion-exchange media, specifically to evaluate the ability of microorganisms to utilize the ion-exchange media or materials sorbed on them as a food source. The ASTM-G22 test, alone and combined with the Bartha Pramer respirometric method, failed to indicate the biodegradability of the ion-exchange media. The limitation of these methods was that they used a single test organism. In later phases of this study, a mixed microbial culture was grown from resin waste samples obtained from the BNL High Flux Beam Reactor. These microorganisms were used to evaluate the susceptibility of different types of ion-exchange media to biological attack. Qualitative assessments of biodegradability were based on visual observations of culture growths. Greater susceptibility was associated with increased turbidity in solution indicative of bacterial growth, and more luxuriant fungal mycelial growth in solution or directly on the ion-exchange resin beads. 21 refs., 9 figs., 18 tabs

  17. Corexit 9500 Enhances Oil Biodegradation and Changes ...

    Science.gov (United States)

    While COREXIT 9500 is widely applied after oil spills for its reported dispersing activity, there is still a debate on the effectiveness on enhancing oil biodegradation and its potential toxic effect on microbial communities. To better understand the impact of COREXIT 9500 on the structure and activity levels of hydrocarbon degrading microbial communities, we analyzed next-generation 16S rRNA gene sequencing libraries of hydrocarbon enrichments grown at cryophilic and mesophilic conditions and using both DNA and RNA extracts as sequencing templates. Oil biodegradation patterns in both cryophilic and mesophilic enrichments were consistent with those reported in the literature (i.e., aliphatics were degraded faster than aromatics). A slight increase in biodegradation was observed in the presence of COREXIT at both 25°C and 5°C experiments. Differences in community structure were observed between treatment conditions in the DNA-based libraries. The 25°C consortia was dominated by unclassified members of the Vibrio, Pseudoidiomarina, Marinobacter, Alcanivorax, and Thallassospira species, while the 5°C consortia were dominated by several genera of Flavobacteria, Alcanivorax and Oleispira. With the exception of Vibrio-like species, members of these genera have been linked to hydrocarbon degradation and have been observed after oil spills. Colwellia and Cycloclasticus, known aromatic degraders, was also found in these enrichments. RNA-based sequencing of 25°C

  18. Development of a biodegradable bone cement

    International Nuclear Information System (INIS)

    Yusof Abdullah; Nurhaslinda Ee Abdullah; Wee Pee Chai; Norita Mohd Zain

    2002-01-01

    Biodegradable bone cement is a newly developed bone repair material, which is able to give immediate support to the implant area, and does not obstruct the bone repairing and regeneration process through appropriate biodegradation rate, which is synchronized with the mechanical load it should bear. The purpose of this study is to locally produce biodegradable bone cement using HA as absorbable filler. The cement is composed of an absorbable filler and unsaturated polyester for 100% degradation. Cross-linking effect is achieved through the action of poly (vinyl pyrrol lidone) (PVP) and an initiator. On the other hand, PPF was synthesized using direct esterification method. Characteristics of the bone cement were studied; these included the curing time, cross-linking effect and curing temperature. The products were characterized using X-Ray diffraction (XRD) to perform phase analysis and Scanning Electrons Microscopes to determine the morphology. The physical and mechanical properties of the bone cement were also investigated. The biocompatibility of the bone cement was tested using simulated body physiological solution. (Author)

  19. Recent advances on liposomal nanoparticles: synthesis, characterization and biomedical applications.

    Science.gov (United States)

    Panahi, Yunes; Farshbaf, Masoud; Mohammadhosseini, Majid; Mirahadi, Mozhdeh; Khalilov, Rovshan; Saghfi, Siamak; Akbarzadeh, Abolfazl

    2017-06-01

    Liposome is a new nanostructure for the encapsulation and delivery of bioactive agents. There are a lot of bioactive materials that could be incorporated into liposomes including cosmetics, food ingredients, and pharmaceuticals. Liposomes possess particular properties such as biocompatibility, biodegradability; accompanied by their nanosize they have potential applications in nanomedicine, cosmetics, and food industry. Nanoliposome technology offers thrilling chances for food technologists in fields including encapsulation and controlled release of food ingredients, also improved bioavailability and stability of sensitive materials. Amid numerous brilliant new drug and gene delivery systems, liposomes provide an advanced technology to carry active molecules to the specific site of action, and now days, various formulations are in clinical use. In this paper, we provide review of the main physicochemical properties of liposomes, current methods of the manufacturing and introduce some of their usage in food nanotechnology as carrier vehicles of nutrients, enzymes, and food antimicrobials and their applications as drug carriers and gene delivery agents in biomedicine.

  20. Best conditions for biodegradation of diesel oil by chemometric tools

    OpenAIRE

    Kaczorek, Ewa; Bielicka-Daszkiewicz, Katarzyna; Héberger, Károly; Kemény, Sándor; Olszanowski, Andrzej; Voelkel, Adam

    2014-01-01

    Diesel oil biodegradation by different bacteria-yeast-rhamnolipids consortia was tested. Chromatographic analysis of post-biodegradation residue was completed with chemometric tools (ANOVA, and a novel ranking procedure based on the sum of ranking differences). These tools were used in the selection of the most effective systems. The best results of aliphatic fractions of diesel oil biodegradation were observed for a yeast consortia with Aeromonas hydrophila KR4. For these systems the positiv...

  1. Biodegradation of flax fiber reinforced poly lactic acid

    Directory of Open Access Journals (Sweden)

    2010-07-01

    Full Text Available Woven and nonwoven flax fiber reinforced poly lactic acid (PLA biocomposites were prepared with amphiphilic additives as accelerator for biodegradation. The prepared composites were buried in farmland soil for biodegradability studies. Loss in weight of the biodegraded composite samples was determined at different time intervals. The surface morphology of the biodegraded composites was studied with scanning electron microscope (SEM. Results indicated that in presence of mandelic acid, the composites showed accelerated biodegradation with 20–25% loss in weight after 50–60 days. On the other hand, in presence of dicumyl peroxide (as additive, biodegradation of the composites was relatively slow as confirmed by only 5–10% loss in weight even after 80–90 days. This was further confirmed by surface morphology of the biodegraded composites. We have attempted to show that depending on the end uses, we can add different amphiphilic additives for delayed or accelerated biodegradability. This work gives us the idea of biodegradation of materials from natural fiber reinforced PLA composites when discarded carelessly in the environment instead of proper waste disposal site.

  2. Accelerating Quinoline Biodegradation and Oxidation with Endogenous Electron Donors.

    Science.gov (United States)

    Bai, Qi; Yang, Lihui; Li, Rongjie; Chen, Bin; Zhang, Lili; Zhang, Yongming; Rittmann, Bruce E

    2015-10-06

    Quinoline, a recalcitrant heterocyclic compound, is biodegraded by a series of reactions that begin with mono-oxygenations, which require an intracellular electron donor. Photolysis of quinoline can generate readily biodegradable products, such as oxalate, whose bio-oxidation can generate endogenous electron donors that ought to accelerate quinoline biodegradation and, ultimately, mineralization. To test this hypothesis, we compared three protocols for the biodegradation of quinoline: direct biodegradation (B), biodegradation after photolysis of 1 h (P1h+B) or 2 h (P2h+B), and biodegradation by adding oxalate commensurate to the amount generated from photolysis of 1 h (O1+B) or 2 h (O2+B). The experimental results show that P1h+B and P2h+B accelerated quinoline biodegradation by 19% and 50%, respectively, compared to B. Protocols O1+B and O2+B also gave 19% and 50% increases, respectively. During quinoline biodegradation, its first intermediate, 2-hydroxyquinoline, accumulated gradually in parallel to quinoline loss but declined once quinoline was depleted. Mono-oxygenation of 2-hydroxyquinoline competed with mono-oxygenation of quinoline, but the inhibition was relieved when extra electrons donors were added from oxalate, whether formed by UV photolysis or added exogenously. Rapid oxalate oxidation stimulated both mono-oxygenations, which accelerated the overall quinoline oxidation that provided the bulk of the electron donor.

  3. Biodegradation of endosulfan by mixed bacteria culture strains of ...

    African Journals Online (AJOL)

    Biodegradation of endosulfan by mixed bacteria culture strains of Pseudomonas aeruginosa and Staphylococcus aureus. Nsidibeabasi Calvin Nwokem, Calvin Onyedika Nwokem, Casmir Emmanuel Gimba, Beatrice Nkiruka Iwuala ...

  4. Biodegradable and bio-based polymers: future prospects of eco-friendly plastics.

    Science.gov (United States)

    Iwata, Tadahisa

    2015-03-09

    Currently used plastics are mostly produced from petrochemical products, but there is a growing demand for eco-friendly plastics. The use of bio-based plastics, which are produced from renewable resources, and biodegradable plastics, which are degraded in the environment, will lead to a more sustainable society and help us solve global environmental and waste management problems. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Regeneration of Surgically Excised Segments of Dog Esophagus using Biodegradable PLA Hollow Organ Grafts,

    Science.gov (United States)

    1980-06-01

    7 AG 396 ARMY INST OF DENTAL RESEARCH WASHINGTON DC FIG 6/5 REGENERATION OF SURGICALLY EXCISED SEGMENTS OF DOG ESOPHAGUS US-ETC(W) U15 G’OE UN8 N F...which will yield effective long-term functional results. The current therapy for repair and replacement of the diseased or avulsed esophagus is by the...C biodegradable polymeric implant constructed from the polymers and copolymers of polylactic acid (PLA) and polyglycolic acid (PGA) to replace an

  6. Biodegradability and toxicity assessment of a real textile wastewater effluent treated by an optimized electrocoagulation process.

    Science.gov (United States)

    Manenti, Diego R; Módenes, Aparecido N; Soares, Petrick A; Boaventura, Rui A R; Palácio, Soraya M; Borba, Fernando H; Espinoza-Quiñones, Fernando R; Bergamasco, Rosângela; Vilar, Vítor J P

    2015-01-01

    In this work, the application of an iron electrode-based electrocoagulation (EC) process on the treatment of a real textile wastewater (RTW) was investigated. In order to perform an efficient integration of the EC process with a biological oxidation one, an enhancement in the biodegradability and low toxicity of final compounds was sought. Optimal values of EC reactor operation parameters (pH, current density and electrolysis time) were achieved by applying a full factorial 3(3) experimental design. Biodegradability and toxicity assays were performed on treated RTW samples obtained at the optimal values of: pH of the solution (7.0), current density (142.9 A m(-2)) and different electrolysis times. As response variables for the biodegradability and toxicity assessment, the Zahn-Wellens test (Dt), the ratio values of dissolved organic carbon (DOC) relative to low-molecular-weight carboxylates anions (LMCA) and lethal concentration 50 (LC50) were used. According to the Dt, the DOC/LMCA ratio and LC50, an electrolysis time of 15 min along with the optimal values of pH and current density were suggested as suitable for a next stage of treatment based on a biological oxidation process.

  7. Dataset on the impact of UV, nitric acid and surfactant treatments on low-density polyethylene biodegradation.

    Science.gov (United States)

    Pathak, Vinay Mohan; Kumar, Navneet

    2017-10-01

    Present investigation evaluates the LDPE (low-density polyethylene) biodegradation efficiency of polymer degrading bacteria along with UV, nitric acid and surfactant treatments. In current scenario LDPE contamination reported as dominant pollutant in terrestrial and aquatic ecosystem due to its expulsion from commercial and domestic practices. Biodegradation serve as an innovative and effective approach to waste management as compared to land filling and burning processes. The outcomes of UV, nitric acid and surfactant treatments on polymer degradation in addition to bacterial treatment were determined by SEM, FT-IR and electrical conductivity analysis.

  8. Dataset on the impact of UV, nitric acid and surfactant treatments on low-density polyethylene biodegradation

    Directory of Open Access Journals (Sweden)

    Vinay Mohan Pathak

    2017-10-01

    Full Text Available Present investigation evaluates the LDPE (low-density polyethylene biodegradation efficiency of polymer degrading bacteria along with UV, nitric acid and surfactant treatments. In current scenario LDPE contamination reported as dominant pollutant in terrestrial and aquatic ecosystem due to its expulsion from commercial and domestic practices. Biodegradation serve as an innovative and effective approach to waste management as compared to land filling and burning processes. The outcomes of UV, nitric acid and surfactant treatments on polymer degradation in addition to bacterial treatment were determined by SEM, FT-IR and electrical conductivity analysis.

  9. Sorption kinetics and microbial biodegradation activity of hydrophobic chemicals in sewage sludge: Model and measurements based on free concentrations

    NARCIS (Netherlands)

    Artola-Garicano, E.; Borkent, I.; Damen, K.; Jager, T.; Vaes, W.H.J.

    2003-01-01

    In the current study, a new method is introduced with which the rate-limiting factor of biodegradation processes of hydrophobic chemicals in organic and aqueous systems can be determined. The novelty of this approach lies in the combination of a free concentration-based kinetic model with

  10. Assessment of in situ biodegradation of chlorinated solvents in aquifers and constructed wetlands using an integrative approach

    OpenAIRE

    Imfeld, Gwenaël; Hunkeler, Daniel

    2009-01-01

    Knowledge about biogeochemical processes associated with natural attenuation of chlorinated solvents in the environment is currently limited. Though processes such as sorption, volatilization or dilution may contribute to contaminant natural attenuation, in situ biodegradation is the only process leading to destructive removal of contaminants. However, the distribution of hydrological and hydrochemical processes over both spatial and temporal scales influence degradation reactions, and thus s...

  11. Synthesis, Properties and Applications of Biodegradable Polymers Derived from Diols and Dicarboxylic Acids: From Polyesters to Poly(ester amides

    Directory of Open Access Journals (Sweden)

    Angélica Díaz

    2014-04-01

    Full Text Available Poly(alkylene dicarboxylates constitute a family of biodegradable polymers with increasing interest for both commodity and speciality applications. Most of these polymers can be prepared from biobased diols and dicarboxylic acids such as 1,4-butanediol, succinic acid and carbohydrates. This review provides a current status report concerning synthesis, biodegradation and applications of a series of polymers that cover a wide range of properties, namely, materials from elastomeric to rigid characteristics that are suitable for applications such as hydrogels, soft tissue engineering, drug delivery systems and liquid crystals. Finally, the incorporation of aromatic units and α-amino acids is considered since stiffness of molecular chains and intermolecular interactions can be drastically changed. In fact, poly(ester amides derived from naturally occurring amino acids offer great possibilities as biodegradable materials for biomedical applications which are also extensively discussed.

  12. An entropy spring model for the Young's modulus change of biodegradable polymers during biodegradation.

    Science.gov (United States)

    Wang, Ying; Han, Xiaoxiao; Pan, Jingzhe; Sinka, Csaba

    2010-01-01

    This paper presents a model for the change in Young's modulus of biodegradable polymers due to hydrolysis cleavage of the polymer chains. The model is based on the entropy spring theory for amorphous polymers. It is assumed that isolated polymer chain cleavage and very short polymer chains do not affect the entropy change in a linear biodegradable polymer during its deformation. It is then possible to relate the Young's modulus to the average molecular weight in a computer simulated hydrolysis process of polymer chain sessions. The experimental data obtained by Tsuji [Tsuji, H., 2002. Autocatalytic hydrolysis of amorphous-made polylactides: Effects of L-lactide content, tacticity, and enantiomeric polymer blending. Polymers 43, 1789-1796] for poly(L-lactic acid) and poly(D-lactic acid) are examined using the model. It is shown that the model can provide a common thread through Tsuji's experimental data. A further numerical case study demonstrates that the Young's modulus obtained using very thin samples, such as those obtained by Tsuji, cannot be directly used to calculate the load carried by a device made of the same polymer but of various thicknesses. This is because the Young's modulus varies significantly in a biodegradable device due to the heterogeneous nature of the hydrolysis reaction. The governing equations for biodegradation and the relation between the Young's modulus and average molecular weight can be combined to calculate the load transfer from a degrading device to a healing bone.

  13. Preparation of new biodegradable materials by grafting of polycarprolactone onto starch and their biodegradability studies

    International Nuclear Information System (INIS)

    Najemi, L.; Zerroukhi, A.; Jeanmaire, T.; Raihane, M.; Chamkh, F.; Qatibi, A.; Bennisse, R.

    2009-01-01

    The starch is a natural polymer which has the advantage of being biodegradable, renewable in quantity unlimited at very accessible prices. However its poor mechanical properties, depending on its hydrophobic character, and also its absorption of water restrict is applicability considerable especially for packing. (Author)

  14. Advances in pediatrics in 2014: current practices and challenges in allergy, gastroenterology, infectious diseases, neonatology, nutrition, oncology and respiratory tract illnesses.

    Science.gov (United States)

    Caffarelli, Carlo; Santamaria, Francesca; Cesari, Silvia; Sciorio, Elisa; Povesi-Dascola, Carlotta; Bernasconi, Sergio

    2015-10-31

    Major advances in the conduct of pediatric practice have been reported in the Italian Journal of Pediatrics in 2014. This review highlights developments in allergy, gastroenterology, infectious diseases, neonatology, nutrition, oncology and respiratory tract illnesses. Investigations endorse a need to better educate guardians and improve nutritional management in food allergy. Management of hyperbilirubinemia in neonates and of bronchiolitis have been improved by position statements of scientific societies. Novel treatments for infant colic and inflammatory bowel diseases have emerged. Studies suggest the diagnostic utility of ultrasonography in diagnosing community-acquired pneumonia. Progress in infectious diseases should include the universal varicella vaccination of children. Recommendations on asphyxia and respiratory distress syndrome have been highlighted in neonatology. Studies have evidenced that malnutrition remains a common underestimated problem in developing countries, while exposure to cancer risk factors in children is not negligible in Western countries. Advances in our understanding of less common diseases such as cystic fibrosis, plastic bronchitis, idiopathic pulmonary hemosiderosis facilitate diagnosis and management. Researches have led to new therapeutic approaches in patent ductus arteriosus and pediatric malignancies.

  15. Advances in outcomes measurement in rehabilitation medicine: current initiatives from the National Institutes of Health and the National Institute on Disability and Rehabilitation Research.

    Science.gov (United States)

    Tulsky, David S; Carlozzi, Noelle E; Cella, David

    2011-10-01

    The articles in this supplement present recent advances in the measurement of patient-reported health-related quality-of-life (HRQOL) outcomes. Specifically, these articles highlight the combined efforts of the National Institutes of Health, National Institute for Neurological Disorders and Stroke, National Center on Medical Rehabilitation Research, National Institute on Disability and Rehabilitation Research, and Department of Veterans Affairs Rehabilitation Research and Development Service to improve HRQOL measurement. In addition, this supplement is intended to provide rehabilitation professionals with information about these efforts and the implications that these advances in outcomes measurement have for rehabilitation medicine and clinical practice. These new measurement scales use state-of-the-art method techniques, including item response theory and computerized adaptive testing. In addition, scale development involves both qualitative and quantitative methods, as well as the administration of items to hundreds or even thousands of research participants. The scales deliberately have been built with overlap of items between scales so that linkages and equivalency scores can be computed. Ultimately, these scales should facilitate direct comparison of outcomes instruments across studies and will serve as standard data elements across research trials without compromising the specificity of disease- or condition-targeted measures. This supplement includes the initial publications for many of these new measurement initiatives, each of which provides researchers and clinicians with better tools for evaluation of the efficacy of their interventions. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  16. Biodegradation of the cyclic nitramine explosives RDX, HMX, and CL-20.

    Science.gov (United States)

    Crocker, Fiona H; Indest, Karl J; Fredrickson, Herbert L

    2006-11-01

    Cyclic nitramine explosives are synthesized globally mainly as military munitions, and their use has resulted in environmental contamination. Several biodegradation pathways have been proposed, and these are based mainly on end-product characterization because many of the metabolic intermediates are hypothetical and unstable in water. Biodegradation mechanisms for cyclic nitramines include (a) formation of a nitramine free radical and loss of nitro functional groups, (b) reduction of nitro functional groups, (c) direct enzymatic cleavage, (d) alpha-hydroxylation, or (e) hydride ion transfer. Pathway intermediates spontaneously decompose in water producing nitrite, nitrous oxide, formaldehyde, or formic acid as common end-products. In vitro enzyme and functional gene expression studies have implicated a limited number of enzymes/genes involved in cyclic nitramine catabolism. Advances in molecular biology methods such as high-throughput DNA sequencing, microarray analysis, and nucleic acid sample preparation are providing access to biochemical and genetic information on cultivable and uncultivable microorganisms. This information can provide the knowledge base for rational engineering of bioremediation strategies, biosensor development, environmental monitoring, and green biosynthesis of explosives. This paper reviews recent developments on the biodegradation of cyclic nitramines and the potential of genomics to identify novel functional genes of explosive metabolism.

  17. Citrate biodegradation. Mid-year status report, [January 1994--June 1994

    International Nuclear Information System (INIS)

    Francis, A.J.; Dodge, C.J.; Chatterjee, S.; Landry, M.F.

    1994-07-01

    The Uranium Soils Integrated Demonstration (USID) Program was established to demonstrate advanced technologies for the remediation of uranium contaminated soils. This program, managed by the Fernald Environmental Restoration Management Corporation (FERMCO), focuses on the development and demonstration of new soil remediation processes which are faster, safer, and more economical for use at the Fernald site and throughout the DOE complex for cleanup of similar contaminants. Brookhaven National Laboratory (BNL) has developed a process which uses citric acid to treat contaminated soils and wastes with the subsequent recovery of toxic metals and uranium. Citric acid, a naturally occurring organic chelating agent, forms multidentate stable complexes with the transition metals and actinides, and has been effectively used to extract uranium and other metals from solid wastes via the formation of soluble metal citrate complexes. Further studies have also shown that several of the metal citrate complexes are readily biodegraded by microorganisms. During this process, the metals form a precipitate or become associated with the biomass and are recovered at the end of the biodegradation. Although uranyl citrate is recalcitrant to biodegradation, upon exposure to visible light it undergoes photochemical degradation resulting in the formation of an insoluble, stable polymeric form of uranium

  18. Biodegradation kinetics for pesticide exposure assessment.

    Science.gov (United States)

    Wolt, J D; Nelson, H P; Cleveland, C B; van Wesenbeeck, I J

    2001-01-01

    Understanding pesticide risks requires characterizing pesticide exposure within the environment in a manner that can be broadly generalized across widely varied conditions of use. The coupled processes of sorption and soil degradation are especially important for understanding the potential environmental exposure of pesticides. The data obtained from degradation studies are inherently variable and, when limited in extent, lend uncertainty to exposure characterization and risk assessment. Pesticide decline in soils reflects dynamically coupled processes of sorption and degradation that add complexity to the treatment of soil biodegradation data from a kinetic perspective. Additional complexity arises from study design limitations that may not fully account for the decline in microbial activity of test systems, or that may be inadequate for considerations of all potential dissipation routes for a given pesticide. Accordingly, kinetic treatment of data must accommodate a variety of differing approaches starting with very simple assumptions as to reaction dynamics and extending to more involved treatments if warranted by the available experimental data. Selection of the appropriate kinetic model to describe pesticide degradation should rely on statistical evaluation of the data fit to ensure that the models used are not overparameterized. Recognizing the effects of experimental conditions and methods for kinetic treatment of degradation data is critical for making appropriate comparisons among pesticide biodegradation data sets. Assessment of variability in soil half-life among soils is uncertain because for many pesticides the data on soil degradation rate are limited to one or two soils. Reasonable upper-bound estimates of soil half-life are necessary in risk assessment so that estimated environmental concentrations can be developed from exposure models. Thus, an understanding of the variable and uncertain distribution of soil half-lives in the environment is

  19. New aspects on atrazine biodegradation

    Directory of Open Access Journals (Sweden)

    Luciane Sene

    2010-04-01

    Full Text Available The world practice of using agrochemicals for long periods, in an indiscriminated and abusive way, has been a concern of the authorities involved in public health and sustainability of the natural resources, as a consequence of environmental contamination. Agrochemicals refer to a broad range of insecticides, fungicides and herbicides, and among them stands out atrazine, a herbicide intensively used in sugarcane, corn and sorghum cultures, among others. Researches have demonstrated that atrazine has toxic effects in algae, aquatic plants, aquatic insects, fishes and mammals. Due to the toxicity and persistence of atrazine in the environment, the search of microbial strains capable of degrading it is fundamental to the development of bioremediation processes, as corrective tools to solve the current problems of the irrational use of agrochemicals. This review relates the main microbial aspects and research on atrazine degradation by isolated microbial species and microbial consortia, as well as approaches on the development of techniques for microbial removal of atrazine in natural environments.A prática mundial do uso de agroquímicos por períodos extensos, de maneira indiscriminada e abusiva, tem mobilizado as autoridades envolvidas em saúde pública e sustentabilidade de fontes naturais, como uma conseqüência da contaminação ambiental. Agroquímicos referem-se a uma ampla variedade de inseticidas, fungicidas e herbicidas, entre estes a atrazina, um herbicida intensivamente usado em culturas de cana-de-açúcar, milho, sorgo, entre outros. Pesquisadores têm demonstrado que a atrazina tem efeitos tóxicos em algas, plantas aquáticas, insetos aquáticos, peixes e mamíferos. Devido à toxicidade e à persistência da atrazina no ambiente, a busca de linhagens microbianas capazes de degradá-la é fundamental para o desenvolvimento de processos de biorremediação, com uma ferramenta corretiva para solucionar problemas decorridos do uso

  20. Integrating biodegradation and electroosmosis for the enhanced removal of polycyclic aromatic hydrocarbons from creosote-polluted soils.

    Science.gov (United States)

    Niqui-Arroyo, José-Luis; Ortega-Calvo, José-Julio

    2007-01-01

    This paper presents a hybrid technology of soil remediation based on the integration of biodegradation and electroosmosis. We employed soils with different texture (clay soil and loamy sand) containing a mixture of polycyclic aromatic hydrocarbons (PAH) present in creosote, and inoculation with a representative soil bacterium able to degrade fluorene, phenanthrene, fluoranthene, pyrene, anthracene, and benzo[a]pyrene. Two different modes of treatment were prospected: (i) inducing in soil the simultaneous occurrence of biodegradation and electroosmosis in the presence of a biodegradable surfactant, and (ii) treating the soils sequentially with electrokinetics and bioremediation. Losses of PAH due to simultaneous biodegradation and electroosmosis (induced by a continuous electric field) were significantly higher than in control cells that contained the surfactant but no biological activity or no current. The method was especially successful with loamy sand. For example, benzo[a]pyrene decreased its concentration by 50% after 7 d, whereas 22 and 17% of the compound had disappeared as a result of electrokinetic flushing and bioremediation alone, respectively. The use of periodical changes in polarity and current pulses increased by 16% in the removal of total PAH and in up to 30% of specific compounds, including benzo[a]pyrene. With the aim of reaching lower residual levels through bioremediation, an electrokinetic pretreatment was also evaluated as a way to mobilize the less bioaccessible fraction of PAH. Residual concentrations of total biodegradable PAH, remaining after bioremediation in soil slurries, were twofold lower in electrokinetically pretreated soils than in untreated soils. The results indicate that biodegradation and electroosmosis can be successfully integrated to promote the removal of PAH from soil.

  1. Biodegradable Poly(polyol sebacate) Polymers

    OpenAIRE

    Bruggeman, Joost P.; de Bruin, Berend-Jan; Bettinger, Christopher J.; Langer, Robert

    2008-01-01

    We have developed a family of synthetic biodegradable polymers that are composed of structural units endogenous to the human metabolism, designated poly(polyol sebacates) (PPS) polymers. Material properties of PPS polymers can be tuned by altering the polyol monomer and reacting stiochiometric ratio of sebacic acid. These thermoset networks exhibited tensile Young’s moduli ranging from 0.37 ± 0.08 to 378 ± 33 MPa with maximum elongations at break from 10.90 ± 1.37 to 205.16 ± 55.76%, and glas...

  2. Development of biodegradable fungicide by radiation

    International Nuclear Information System (INIS)

    Lee, Young Jeun; Kim, Dong Sub

    2010-01-01

    To develop the fungicide which is biodegradable and alternative to chemical pesticide that has an side effect of environmental pollution, Mutant induction of the enhanced antifungal activity was studied by using radiation. Characteristics and structure of antifungal biomaterials derived from these mutants were analysed. Sixteen antifungal microbes were isolated and 4 antifungal activity enhanced mutants were induced by using radiation. P. lentimorbus WJ5a17 had 41% higher antifungal activity than the wild type. Two biomaterials related to the antifungal activity from the above mutant were isolated and purified

  3. Development of biodegradable fungicide by radiation

    International Nuclear Information System (INIS)

    Lee, Young Keun; Kim, Dong Sub

    2011-01-01

    To develop the fungicide which is biodegradable and alternative to chemical pesticide that has an side effect of environmental pollution, Mutant induction of the enhanced antifungal activity was studied by using radiation. Characteristics and structure of antifungal biomaterials derived from these mutants were analysed. Two biomaterials related to the antifungal activity from the above mutant were isolated and purified. Microbial pesticide were manufactured in combination of various additives. Antiphytopathogenic effects were proven by pot experiment and It was promising to prevent pepper, Chinese cabbage and radish from anthrax, phytophthora and root rot

  4. Lipase biocatalysis for useful biodegradable products

    Energy Technology Data Exchange (ETDEWEB)

    Linko, Y.Y.; Wang, Zhuo Lin; Uosukainen, E.; Seppaelae, J. [Helsinki Univ. of Technology, Espoo (Finland); Laemsae, M. [Raisio Group Oil Milling Industry, Raisio (Finland)

    1996-12-31

    It was shown that lipases can be used as biocatalysts in the production of useful biodegradable compounds such as 1-butyl oleate by direct esterification of butanol and oleic acid to decrease viscosity of biodiesel in winter use. By enzymic transesterification, a mixture of 2-ethyl-1-hexyl esters from rapeseed oil fatty acids can be obtained in good yields for use as a solvent, and of trimethylolpropane esters for use as a lubricant. Finally, it was demonstrated that polyesters with a mass average molar mass in excess of 75,000 g mol{sup -}1 can be obtained by esterification or transesterification by using lipase as biocatalyst. (author) (3 refs.)

  5. Biodegradation of polyurethanes; Polyurethane no biseibutsu bunkai

    Energy Technology Data Exchange (ETDEWEB)

    Kinpara, N.; Ando, M.; Ohira, Z. [Suzuki Motor Corp., Shizuoka (Japan); Nakajima, T.; Nakahara, T. [University of Tsukuba, Tsukuba (Japan)

    1997-10-01

    Different types of Polyurethane (PUR) are used for various industrial products and are used in increasing quantities every year. We experimented with biodegradation of PURs to dispose of industrial wastes. 2 strains of fungi and 1 strain of bacteria which were seemed to have the ability to degrade PURs well were isolated from various soils and waste water. These strains could degrade ester-type PUR and PUR made from a mixture of ester and ether. However, these strains could not degrade ether-type PUR. From Scanning Electron Microscopy observation, it is suggested that the microbial degradation proceeded in at least 2 patterns. 4 refs., 8 figs., 2 tabs.

  6. Development of biodegradable fungicide by radiation

    International Nuclear Information System (INIS)

    Lee, Youngkeun; Kim, Dongsub

    2012-03-01

    To develop the fungicide which is biodegradable and alternative to chemical pesticide that has an side effect of environmental pollution, Mutant induction of the enhanced antifungal activity was studied by using radiation. Characteristics and structure of antifungal biomaterials derived from these mutants were analysed. Two biomaterials related to the antifungal activity from the above mutant were isolated and purified. Microbial pesticide were manufactured in combination of various additives. Antiphytopathogenic effects were proven by field test and it was promising to prevent Chinese cabbage and radish from phytophthora and root rot

  7. Development of biodegradable fungicide by radiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Keun; Kim, Dong Sub [KAERI, Daejeon (Korea, Republic of)

    2011-01-15

    To develop the fungicide which is biodegradable and alternative to chemical pesticide that has an side effect of environmental pollution, Mutant induction of the enhanced antifungal activity was studied by using radiation. Characteristics and structure of antifungal biomaterials derived from these mutants were analysed. Two biomaterials related to the antifungal activity from the above mutant were isolated and purified. Microbial pesticide were manufactured in combination of various additives. Antiphytopathogenic effects were proven by pot experiment and It was promising to prevent pepper, Chinese cabbage and radish from anthrax, phytophthora and root rot

  8. Development of biodegradable fungicide by radiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Youngkeun; Kim, Dongsub

    2012-03-15

    To develop the fungicide which is biodegradable and alternative to chemical pesticide that has an side effect of environmental pollution, Mutant induction of the enhanced antifungal activity was studied by using radiation. Characteristics and structure of antifungal biomaterials derived from these mutants were analysed. Two biomaterials related to the antifungal activity from the above mutant were isolated and purified. Microbial pesticide were manufactured in combination of various additives. Antiphytopathogenic effects were proven by field test and it was promising to prevent Chinese cabbage and radish from phytophthora and root rot.

  9. Hydrocarbons biodegradation in unsaturated porous medium; Biodegradation des hydrocarbures en milieu poreux insature

    Energy Technology Data Exchange (ETDEWEB)

    Gautier, C

    2007-12-15

    Biological processes are expected to play an important role in the degradation of petroleum hydrocarbons in contaminated soils. However, factors influencing the kinetics of biodegradation are still not well known, especially in the unsaturated zone. To address these biodegradation questions in the unsaturated zone an innovative experimental set up based on a physical column model was developed. This experimental set up appeared to be an excellent tool for elaboration of a structured porous medium, with well defined porous network and adjusted water/oil saturations. Homogeneous repartition of both liquid phases (i.e., aqueous and non aqueous) in the soil pores, which also contain air, was achieved using ceramic membranes placed at the bottom of the soil column. Reproducible interfaces (and connectivity) are developed between gas, and both non mobile water and NAPL phases, depending on the above-defined characteristics of the porous media and on the partial saturations of these three phases (NAPL, water and gas). A respirometric apparatus was coupled to the column. Such experimental set up have been validated with hexadecane in dilution in an HMN phase. This approach allowed detailed information concerning n-hexadecane biodegradation, in aerobic condition, through the profile of the oxygen consumption rate. We have taken benefit of this technique, varying experimental conditions, to determine the main parameters influencing the biodegradation kinetics and compositional evolution of hydrocarbons, under steady state unsaturated conditions and with respect to aerobic metabolism. Impacts of the nitrogen quantity and of three different grain sizes have been examined. Biodegradation of petroleum cut, as diesel cut and middle distillate without aromatic fraction, were, also studied. (author)

  10. Biodegradation performance of environmentally-friendly insulating oil

    Science.gov (United States)

    Yang, Jun; He, Yan; Cai, Shengwei; Chen, Cheng; Wen, Gang; Wang, Feipeng; Fan, Fan; Wan, Chunxiang; Wu, Liya; Liu, Ruitong

    2018-02-01

    In this paper, biodegradation performance of rapeseed insulating oil (RDB) and FR3 insulating oil (FR3) was studied by means of ready biodegradation method which was performed with Organization for Economic Co-operation and Development (OECD) 301B. For comparison, the biodegradation behaviour of 25# mineral insulating oil was also characterized with the same method. The testing results shown that the biodegradation degree of rapeseed insulating oil, FR3 insulating oil and 25# mineral insulating oil was 95.8%, 98.9% and 38.4% respectively. Following the “new chemical risk assessment guidelines” (HJ/T 154 - 2004), which illustrates the methods used to identify and assess the process safety hazards inherent. The guidelines can draw that the two vegetable insulating oils, i.e. rapeseed insulating oil and FR3 insulating oil are easily biodegradable. Therefore, the both can be classified as environmentally-friendly insulating oil. As expected, 25# mineral insulating oil is hardly biodegradable. The main reason is that 25# mineral insulating oil consists of isoalkanes, cyclanes and a few arenes, which has few unsaturated bonds. Biodegradation of rapeseed insulating oil and FR3 insulating oil also remain some difference. Biodegradation mechanism of vegetable insulating oil was revealed from the perspective of hydrolysis kinetics.

  11. Cellulose sulphuric acid as a biodegradable catalyst for conversion ...

    Indian Academy of Sciences (India)

    Cellulose sulphuric acid as a biodegradable catalyst for conversion of aryl amines into azides at room temperature under mild conditions. Firouzeh Nesmati Ali Elhampour. Volume 124 Issue 4 July 2012 ... Keywords. Cellulose sulphuric acid; aryl azides; diazotization; biodegradable. ... Supplementary Material. supp18.pdf ...

  12. Studies on the biodegradation of natural and synthetic polyethylene ...

    African Journals Online (AJOL)

    Michael Horsfall

    performed for the purpose of biodegradation. The natural or biodegradable polyethylene used in the study was disposable plastic bags containing 6% vegetable starch. The initial and final dry weights of plastic bags before and after incubation in the culture medium were compared and the percentage of degradation was ...

  13. Nanocomposites with biodegradable polymers synthesis properties and future perspectives

    CERN Document Server

    2011-01-01

    Polymers are used in practically every facet of daily life. Most polymers come from fossil fuels and are not biodegradable, causing long-term environmental hazards. Biodegradable polymers provide an alternative class of materials. Composites of such polymers have high potential within a wide spectrum of applications.

  14. Biodegradable elastomers for biomedical applications and regenerative medicine

    NARCIS (Netherlands)

    Bat, E.; Zhang Zheng, Z.Z.; Feijen, Jan; Grijpma, Dirk W.; Poot, Andreas A.

    2014-01-01

    Synthetic biodegradable polymers are of great value for the preparation of implants that are required to reside only temporarily in the body. The use of biodegradable polymers obviates the need for a second surgery to remove the implant, which is the case when a nondegradable implant is used. After

  15. Microbial biodegradable potato starch based low density polyethylene

    African Journals Online (AJOL)

    Plastic materials remain in the nature for decades. Slow degradation of plastics in the environment caused a public trend to biodegradable polymers. The aim of this research was to produce the microbial biodegradable low density polyethylene with potato starch. Degradation of potato starch based low density polyethylene ...

  16. Biodegradative activities of some gram- negative bacilli isolated ...

    African Journals Online (AJOL)

    Their biodegradative activities were studied and confirmed by the change in the Total Petroleum Hydrocarbon (TPH) using gravimetric method. The biodegradative abilities of the isolates were compared by measuring the optical densities, total viable count, pH and emulsification activity. The results showed that the ...

  17. Effect of adsorption and aqueous speciation on nitrilotriacetate biodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Girvin, D.C.; Bolton, H. Jr. [Pacific Northwest Lab., Richland, WA (United States)

    1995-12-01

    Nitrilotriacetic acid (NTA) forms strong water soluable complexes with a wide range of radionuclide and metal ions. Knowledge of sorption-biodegradation interactions is essential to predict the environmental transport of radionuclide-NTA complexes. Biodegradation of NTA and cobalt-NTA by Chelatobacter heintzii was investigated.

  18. Biodegradation of Lagoma crude oil using pig dung | Yakubu ...

    African Journals Online (AJOL)

    Pig dung bacteria were isolated and screened for crude oil degrading capabilities. The pig dung was also investigated for enhancement of crude oil biodegradation. Addition of chicken manure to oil polluted soil (at 10% (v/w) pollution level) stimulated the biodegradation of lagoma crude oil used in the present study.

  19. Biodegradation of clofibric acid and identification of its metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Salgado, R. [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); ESTS-IPS, Escola Superior de Tecnologia de Setubal do Instituto Politecnico de Setubal, Rua Vale de Chaves, Campus do IPS, Estefanilha, 2910-761 Setubal (Portugal); Oehmen, A. [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Carvalho, G. [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Instituto de Biologia Experimental e Tecnologica (IBET), Av. da Republica (EAN), 2784-505 Oeiras (Portugal); Noronha, J.P. [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Reis, M.A.M., E-mail: amr@fct.unl.pt [REQUIMTE/CQFB, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

    2012-11-30

    Graphical abstract: Metabolites produced during clofibric acid biodegradation. Highlights: Black-Right-Pointing-Pointer Clofibric acid is biodegradable. Black-Right-Pointing-Pointer Mainly heterotrophic bacteria degraded the clofibric acid. Black-Right-Pointing-Pointer Metabolites of clofibric acid biodegradation were identified. Black-Right-Pointing-Pointer The metabolic pathway of clofibric acid biodegradation is proposed. - Abstract: Clofibric acid (CLF) is the pharmaceutically active metabolite of lipid regulators clofibrate, etofibrate and etofyllinclofibrate, and it is considered both environmentally persistent and refractory. This work studied the biotransformation of CLF in aerobic sequencing batch reactors (SBRs) with mixed microbial cultures, monitoring the efficiency of biotransformation of CLF and the production of metabolites. The maximum removal achieved was 51% biodegradation (initial CLF concentration = 2 mg L{sup -1}), where adsorption and abiotic removal mechanisms were shown to be negligible, showing that CLF is indeed biodegradable. Tests showed that the observed CLF biodegradation was mainly carried out by heterotrophic bacteria. Three main metabolites were identified, including {alpha}-hydroxyisobutyric acid, lactic acid and 4-chlorophenol. The latter is known to exhibit higher toxicity than the parent compound, but it did not accumulate in the SBRs. {alpha}-Hydroxyisobutyric acid and lactic acid accumulated for a period, where nitrite accumulation may have been responsible for inhibiting their degradation. A metabolic pathway for the biodegradation of CLF is proposed in this study.

  20. Biodegradable elastomers for biomedical applications and regenerative medicine

    NARCIS (Netherlands)

    Bat, Erhan; Zhang, Zheng; Feijen, Jan; Grijpma, Dirk W.; Poot, Andre A.

    Synthetic biodegradable polymers are of great value for the preparation of implants that are required to reside only temporarily in the body. The use of biodegradable polymers obviates the need for a second surgery to remove the implant, which is the case when a nondegradable implant is used. After

  1. Torsion strenght of biodegradable and titanium screws: a comparison.

    NARCIS (Netherlands)

    Buijs, Gerrit J.; van der Houwen, Eduard B.; Stegenga, Boudewijn; Bos, Rudolf R.M.; Verkerke, Gijsbertus Jacob

    2007-01-01

    Purpose: To determine 1) the differences in maximum torque between 7 biodegradable and 2 titanium screw systems, and 2) the differences of maximum torque between “hand tight” and break of the biodegradable and the titanium osteofixation screw systems. Materials and Methods: Four oral and

  2. Biodegradability of tannin-containing wastewater from leather industry.

    Science.gov (United States)

    He, Qiang; Yao, Kai; Sun, Danhong; Shi, Bi

    2007-08-01

    Tannins occur commonly in the wastewaters from forestry, plant medicine, paper and leather industries. The treatment of this kind of wastewaters, including settling and biodegradation, is usually difficult because tannins are highly soluble in water and would inhibit the growth of microorganisms in activated sludge. The objective of this study is to investigate biodegradability of tannin-containing wastewaters, so as to characterize the pollution properties of such wastewaters and provide a reference for their biological treatment in wastewater treatment plants. The research was typified by using the wastewater collected from vegetable tanning process in leather industry. A model was developed to describe the activated sludge process, and the biodegradation kinetics of vegetable tanning wastewater (VET wastewater) was studied. It was found that the biodegradability of tannin-containing wastewater varies heavily with the content of tannins in wastewater. The biodegradation of VET wastewater with tannin content around 4,900 mg/l occurred inefficiently due to the inhibition of tannins to the activated sludge process, and only 34.7% of biodegradation extent was reached in 14 days of incubation. The optimal biodegradability of VET wastewater was observed when its tannin content was diluted to 490 mg/l, where the COD and tannin removals reached 51.3% and 45.1% respectively in 6 days. Hence, it is suggested that a proper control of tannin content is necessary to achieve an effective biodegradation of tannin-containing wastewaters in wastewater treatment plants.

  3. Sociobiology of biodegradation and the role of predatory protozoa in ...

    Indian Academy of Sciences (India)

    PRAKASH KUMAR

    A variety of protozoa are associated with different biodegrading microbial communities. Some of these protozoa have been shown to produce extracellular enzymes and hence play a direct role in biodegradation (Jouany and. Martin 1997). However, a large number of protozoal species play only a predatory role and mainly ...

  4. Fungal biodegradation of plantain peel for broiler finisher feeding: In ...

    African Journals Online (AJOL)

    ... protein, cholesterol and glucose were significantly (P<0.05) affected by the treatments. Fungal biodegradation of PPL using A.niger has the potential of enhancing feed intake, nutrient digestibility and the body weight gain of broiler finisher. Keywords: Aspergillus niger, biodegradation, nutrient enhancement and broilers.

  5. Polímeros biodegradables. Importancia y potenciales aplicaciones

    OpenAIRE

    Labeaga Viteri, Aitziber

    2018-01-01

    Un polímero biodegradable es aquel que puede ser degradado completamente por el medio ambiente, reduciendo así el impacto ambiental que estos materiales producen. Por lo tanto, de acuerdo con esta definición, cuando un envase plástico biodegradable es

  6. Biodegradable hollow fibres for the controlled release of drugs

    NARCIS (Netherlands)

    Schakenraad, J.M.; Oosterbaan, J.A.; Nieuwenhuis, P.; Molenaar, I.; Olijslager, J.; Potman, W.; Eenink, M.J.D.; Feijen, Jan

    1988-01-01

    Biodegradable hollow fibres of poly-l-lactic acid (PLLA) filled with a suspension of the contraceptive hormone levonorgestrel in castor oil were implanted subcutaneously in rats to study the rate of drug release, rate of biodegradation and tissue reaction caused by the implant. The in vivo drug

  7. Biodegradation of flax fiber reinforced poly lactic acid

    CSIR Research Space (South Africa)

    Kumar, R

    2010-07-01

    Full Text Available , the composites showed accelerated biodegradation with 20–25% loss in weight after 50–60 days. On the other hand, in presence of dicumyl peroxide (as additive), biodegradation of the composites was relatively slow as confirmed by only 5–10% loss in weight even...

  8. Activated Sludge Biodegradation of 12 Commercial Phthalate Esters

    OpenAIRE

    O'Grady, Dean P.; Howard, Philip H.; Werner, A. Frances

    1985-01-01

    The activated sludge biodegradability of 12 commercial phthalate esters was evaluated in two test systems: (i) a semicontinuous activated sludge test and (ii) an acclimated 19-day die-away procedure. Both procedures demonstrated that phthalate esters are rapidly biodegraded under activated sludge conditions when loss of the parent phthalate ester (primary degradation) is measured.

  9. Development of Biomarkers for Assessing In Situ RDX Biodegradation Potential

    Science.gov (United States)

    2010-02-01

    could be used to identify RDX degraders in mixed culture samples. This information can ultimately be used to assess the potential for bioremediation and... bioremediation potential at RDX contaminated sites. 6 ER1606 –Development of Biomarkers for Assessing In Situ RDX...Microbial populations related to PAH biodegradation in an aged biostimulated creosote -contaminated soil. Biodegradation 20,593-601. Ludwig, W

  10. Perspective highlights on biodegradable polymeric nanosystems for targeted therapy of solid tumors.

    Science.gov (United States)

    Fathi, Marziyeh; Barar, Jaleh

    2017-01-01

    Introduction: Polymeric nanoparticles (NPs) formulated using biodegradable polymers offer great potential for development of de novo drug delivery systems (DDSs) capable of delivering a wide range of bioactive agents. They can be engineered as advanced multifunctional nanosystems (NSs) for simultaneous imaging and therapy known as theranostics or diapeutics. Methods: A brief prospective is provided on biomedical importance and applications of biodegradable polymeric NSs through reviewing the recently published literature. Results: Biodegradable polymeric NPs present unique characteristics, including: nanoscaled structures, high encapsulation capacity, biocompatibility with non-thrombogenic and non-immunogenic properties, and controlled-/sustained-release profile for lipophilic and hydrophilic drugs. Once administered in vivo, all classes of biodegradable polymers (i.e., synthetic, semi-synthetic, and natural polymers) are subjected to enzymatic degradation; and hence, transformation into byproducts that can be simply eliminated from the human body. Natural and semi-synthetic polymers have been shown to be highly stable, much safer, and offer a non-/less-toxic means for specific delivery of cargo drugs in comparison with synthetic polymers. Despite being biocompatible and enzymatically-degradable, there are some drawbacks associated with these polymers such as batch to batch variation, high production cost, structural complexity, lower bioadhesive potential, uncontrolled rate of hydration, and possibility of microbial spoilage. These pitfalls have bolded the importance of synthetic counterparts despite their somewhat toxicity. Conclusion: Taken all, to minimize the inadvertent effects of these polymers and to engineer much safer NSs, it is necessary to devise biopolymers with desirable chemical and biochemical modification(s) and polyelectrolyte complex formation to improve their drug delivery capacity in vivo.

  11. Preliminary inter-model comparison of the Agulhas current with direct range doppler velocity estimates from Envisat's Advanced Synthetic Aperture Radar (ASAR)

    CSIR Research Space (South Africa)

    Backeberg, Bjorn C

    2010-07-01

    Full Text Available The greater Agulhas Current is a highly dynamic regime that is known to have significant influence on the local marine environment and ecosystem. It is also recently recognized to play an important role in the global thermohaline circulation...

  12. Evaluation of Artificial Intelligence Based Models for Chemical Biodegradability Prediction

    Directory of Open Access Journals (Sweden)

    Aleksandar Sabljic

    2004-12-01

    Full Text Available This study presents a review of biodegradability modeling efforts including a detailed assessment of two models developed using an artificial intelligence based methodology. Validation results for these models using an independent, quality reviewed database, demonstrate that the models perform well when compared to another commonly used biodegradability model, against the same data. The ability of models induced by an artificial intelligence methodology to accommodate complex interactions in detailed systems, and the demonstrated reliability of the approach evaluated by this study, indicate that the methodology may have application in broadening the scope of biodegradability models. Given adequate data for biodegradability of chemicals under environmental conditions, this may allow for the development of future models that include such things as surface interface impacts on biodegradability for example.

  13. Best conditions for biodegradation of diesel oil by chemometric tools

    Directory of Open Access Journals (Sweden)

    Ewa Kaczorek

    2014-01-01

    Full Text Available Diesel oil biodegradation by different bacteria-yeast-rhamnolipids consortia was tested. Chromatographic analysis of post-biodegradation residue was completed with chemometric tools (ANOVA, and a novel ranking procedure based on the sum of ranking differences. These tools were used in the selection of the most effective systems. The best results of aliphatic fractions of diesel oil biodegradation were observed for a yeast consortia with Aeromonas hydrophila KR4. For these systems the positive effect of rhamnolipids on hydrocarbon biodegradation was observed. However, rhamnolipids addition did not always have a positive influence on the biodegradation process (e.g. in case of yeast consortia with Stenotrophomonas maltophila KR7. Moreover, particular differences in the degradation pattern were observed for lower and higher alkanes than in the case with C22. Normally, the best conditions for "lower" alkanes are Aeromonas hydrophila KR4 + emulsifier independently from yeasts and e.g. Pseudomonas stutzeri KR7 for C24 alkane.

  14. Best conditions for biodegradation of diesel oil by chemometric tools

    Science.gov (United States)

    Kaczorek, Ewa; Bielicka-Daszkiewicz, Katarzyna; Héberger, Károly; Kemény, Sándor; Olszanowski, Andrzej; Voelkel, Adam

    2014-01-01

    Diesel oil biodegradation by different bacteria-yeast-rhamnolipids consortia was tested. Chromatographic analysis of post-biodegradation residue was completed with chemometric tools (ANOVA, and a novel ranking procedure based on the sum of ranking differences). These tools were used in the selection of the most effective systems. The best results of aliphatic fractions of diesel oil biodegradation were observed for a yeast consortia with Aeromonas hydrophila KR4. For these systems the positive effect of rhamnolipids on hydrocarbon biodegradation was observed. However, rhamnolipids addition did not always have a positive influence on the biodegradation process (e.g. in case of yeast consortia with Stenotrophomonas maltophila KR7). Moreover, particular differences in the degradation pattern were observed for lower and higher alkanes than in the case with C22. Normally, the best conditions for “lower” alkanes are Aeromonas hydrophila KR4 + emulsifier independently from yeasts and e.g. Pseudomonas stutzeri KR7 for C24 alkane. PMID:24948922

  15. Biodegradable Metals for Cardiovascular Stents: from Clinical Concerns to Recent Zn-Alloys.

    Science.gov (United States)

    Bowen, Patrick K; Shearier, Emily R; Zhao, Shan; Guillory, Roger J; Zhao, Feng; Goldman, Jeremy; Drelich, Jaroslaw W

    2016-05-01

    Metallic stents are used to promote revascularization and maintain patency of plaqued or damaged arteries following balloon angioplasty. To mitigate the long-term side effects associated with corrosion-resistant stents (i.e., chronic inflammation and late stage thrombosis), a new generation of so-called "bioabsorbable" stents is currently being developed. The bioabsorbable coronary stents will corrode and be absorbed by the artery after completing their task as vascular scaffolding. Research spanning the last two decades has focused on biodegradable polymeric, iron-based, and magnesium-based stent materials. The inherent mechanical and surface properties of metals make them more attractive stent material candidates than their polymeric counterparts. A third class of metallic bioabsorbable materials that are based on zinc has been introduced in the last few years. This new zinc-based class of materials demonstrates the potential for an absorbable metallic stent with the mechanical and biodegradation characteristics required for optimal stent performance. This review compares bioabsorbable materials and summarizes progress towards bioabsorbable stents. It emphasizes the current understanding of physiological and biological benefits of zinc and its biocompatibility. Finally, the review provides an outlook on challenges in designing zinc-based stents of optimal mechanical properties and biodegradation rate. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Stenting as a palliative method in the management of advanced squamous cell carcinoma of the oesophagus and gastro-oesophageal junction

    Directory of Open Access Journals (Sweden)

    Janusz Wlodarczyk

    2016-03-01

    Full Text Available Advanced squamous cell carcinoma of the oesophagus and gastroesophageal junction usually requires palliative treatment, and the method of choice is stenting. There are several types of stents currently available, including: self-expandable metallic stents (fully or partially covered; self-expandable plastic stents; biodegradable stents. Each of the mentioned stents has its advantages and limitations, and requires a proper, patient-tailored selection. Due to the close anatomical relationship between the oesophagus and bronchial tree, some patients may require bilateral stenting. Oesophageal stenting may not only be considered as a palliative procedure, but can also be implemented to alleviate dysphagia during preoperative chemotherapy and/or radiotherapy.

  17. Electrokinetic enhancement of phenanthrene biodegradation in creosote-polluted clay soil.

    Science.gov (United States)

    Niqui-Arroyo, José-Luis; Bueno-Montes, Marisa; Posada-Baquero, Rosa; Ortega-Calvo, José-Julio

    2006-07-01

    Given the difficulties caused by low-permeable soils in bioremediation, a new electrokinetic technology is proposed, based on laboratory results with phenanthrene, to afford bioremediation of polycyclic aromatic hydrocarbons (PAH) in clay soils. Microbial activity in a clay soil historically polluted with creosote was promoted using a specially designed electrokinetic cell with a permanent anode-to-cathode flow and controlled pH. The rates of phenanthrene losses during treatment were tenfold higher in soil treated with an electric field than in the control cells without current or microbial activity. Results from experiments with Tenax-assisted desorption and mineralization of 14C-labeled phenanthrene indicated that phenanthrene biodegradation was limited by mass-transfer of the chemical. We suggest that the enhancement effect of the applied electric field on phenanthrene biodegradation resulted from mobilization of the PAH and nutrients dissolved in the soil fluids.

  18. Electrokinetic enhancement of phenanthrene biodegradation in creosote-polluted clay soil

    Energy Technology Data Exchange (ETDEWEB)

    Jose-Luis Niqui-Arroyo; Marisa Bueno-Montes; Rosa Posada-Baquero; Jose-Julio Ortega-Calvo [Instituto de Recursos Naturales y Agrobiologia, Seville (Spain)

    2006-07-15

    Given the difficulties caused by low-permeable soils in bioremediation, a new electrokinetic technology is proposed, based on laboratory results with phenanthrene, to afford bioremediation of polycyclic aromatic hydrocarbons (PAH) in clay soils. Microbial activity in a clay soil historically polluted with creosote was promoted using a specially designed electrokinetic cell with a permanent anode-to-cathode flow and controlled pH. The rates of phenanthrene losses during treatment were tenfold higher in soil treated with an electric field than in the control cells without current or microbial activity. Results from experiments with Tenax-assisted desorption and mineralization of {sup 14}C-labeled phenanthrene indicated that phenanthrene biodegradation was limited by mass-transfer of the chemical. We suggest that the enhancement effect of the applied electric field on phenanthrene biodegradation resulted from mobilization of the PAH and nutrients dissolved in the soil fluids.

  19. Oxidation and biodegradation of polyethylene films containing pro-oxidantadditives: Synergistic effects of sunlight exposure, thermal aging and fungal biodegradation

    Science.gov (United States)

    Synergistic effects of sunlight exposure, thermal aging and fungal biodegradation on the oxidation and biodegradation of linear low density poly (ethylene) PE-LLD films containing pro-oxidant were examined. To achieve oxidation and degradation, films were first exposed to the sunlight for 93 days du...

  20. Mathematical modeling of wastewater-derived biodegradable dissolved organic nitrogen.

    Science.gov (United States)

    Simsek, Halis

    2016-11-01

    Wastewater-derived dissolved organic nitrogen (DON) typically constitutes the majority of total dissolved nitrogen (TDN) discharged to surface waters from advanced wastewater treatment plants (WWTPs). When considering the stringent regulations on nitrogen discharge limits in sensitive receiving waters, DON becomes problematic and needs to be reduced. Biodegradable DON (BDON) is a portion of DON that is biologically degradable by bacteria when the optimum environmental conditions are met. BDON in a two-stage trickling filter WWTP was estimated using artificial intelligence techniques, such as adaptive neuro-fuzzy inference systems, multilayer perceptron, radial basis neural networks (RBNN), and generalized regression neural networks. Nitrite, nitrate, ammonium, TDN, and DON data were used as input neurons. Wastewater samples were collected from four different locations in the plant. Model performances were evaluated using root mean square error, mean absolute error, mean bias error, and coefficient of determination statistics. Modeling results showed that the R(2) values were higher than 0.85 in all four models for all wastewater samples, except only R(2) in the final effluent sample for RBNN modeling was low (0.52). Overall, it was found that all four computing techniques could be employed successfully to predict BDON.

  1. A REVIEW ON BIODEGRADABLE STARCH BASED FILM

    Directory of Open Access Journals (Sweden)

    Hooman Molavi

    2015-04-01

    Full Text Available In recent years, biodegradable edible films have become very important in research related to food, due to their compatibility with the environment and their use in the food packaging industry. Various sources can be used in the production of biopolymers as biodegradable films that include polysaccharides, proteins and lipids. Among the various polysaccharides, starch due to its low price and its abundance in nature is of significant importance. Several factors affect the properties of starch films; such as the source which starch is obtained from, as well as the ratio of constituents of the starch. Starch films have advantages such as low thickness, flexibility and transparency though; there are some downsides to mention, such as the poor mechanical properties and water vapor permeability. Thus, using starch alone to produce the film will led to restrictions on its use. To improve the mechanical properties of starch films and also increases resistance against humidity, several methods can be used; including the starch modifying techniques such as cross linking of starch and combining starch with other natural polymers. Other methods such as the use of lipid in formulations of films to increase the resistance to moisture are possible, but lipids are susceptible to oxidation. Therefore, new approaches are based on the integration of different biopolymers in food packaging.

  2. Characterization and aerobic biodegradation of selected monoterpenes

    Energy Technology Data Exchange (ETDEWEB)

    Misra, G.; Pavlostathis, S.G.; Li, J.; Purdue, E.M. [Georgia Institute of Technology, Atlanta, GA (United States)

    1996-12-31

    Monoterpenes are biogenic chemicals and occur in abundance in nature. Large-scale industrial use of these chemicals has recently been initiated in an attempt to replace halogenated solvents and chlorofluorocarbons which have been implicated in the stratospheric depletion of ozone. This study examined four hydrocarbon monoterpenes (d-limonene, {alpha}-pinene, {gamma}-terpinene, and terpinolene) and four alcohols (arbanol, linalool, plinol, and {alpha}-terpineol). Water solubility, vapor pressure, and octanol/water partition coefficients were estimated. Aerobic biodegradability tests were conducted in batch reactors by utilizing forest soil extract and enriched cultures as inoculum. The hydrophobic nature and high volatility of the hydrocarbons restricted the investigation to relatively low aqueous concentrations. Each monoterpene was analyzed with a gas chromatograph equipped with a flame ionization detector after extraction from the aqueous phase with isooctane. Terpene mineralization was tested by monitoring liquid-phase carbon, CO{sub 2} production and biomass growth. All four hydrocarbons and two alcohols readily degraded under aerobic conditions. Plinol resisted degradation in assays using inocula from diverse sources, while arbanol degraded very slowly. The intrinsic biokinetics coefficients for the degradation of d-limonene and {alpha}-terpineol were estimated by using cultures enriched with the respective monoterpenes. Monoterpene biodegradation followed Monod kinetics.

  3. Design Considerations for Developing Biodegradable Magnesium Implants

    Science.gov (United States)

    Brar, Harpreet S.; Keselowsky, Benjamin G.; Sarntinoranont, Malisa; Manuel, Michele V.

    The integration of biodegradable and bioabsorbable magnesium implants into the human body is a complex undertaking that faces major challenges. The complexity arises from the fact that biomaterials must meet both engineering and physiological requirements to ensure the desired properties. Historically, efforts have been focused on the behavior of commercial magnesium alloys in biological environments and their resultant effect on cell-mediated processes. Developing causal relationships between alloy chemistry and micro structure, and its effect on cellular behavior can be a difficult and time intensive process. A systems design approach driven by thermodynamics has the power to provide significant contributions in developing the next generation of magnesium alloy implants with controlled degradability, biocompatibility, and optimized mechanical properties, at reduced time and cost. This approach couples experimental research with theory and mechanistic modeling for the accelerated development of materials. The aim of this article is to enumerate this strategy, design considerations and hurdles for developing new magnesium alloys for use as biodegradable implant materials [1].

  4. Bioavailability of heavy metals in soil: impact on microbial biodegradation of organic compounds and possible improvement strategies.

    Science.gov (United States)

    Olaniran, Ademola O; Balgobind, Adhika; Pillay, Balakrishna

    2013-05-15

    Co-contamination of the environment with toxic chlorinated organic and heavy metal pollutants is one of the major problems facing industrialized nations today. Heavy metals may inhibit biodegradation of chlorinated organics by interacting with enzymes directly involved in biodegradation or those involved in general metabolism. Predictions of metal toxicity effects on organic pollutant biodegradation in co-contaminated soil and water environments is difficult since heavy metals may be present in a variety of chemical and physical forms. Recent advances in bioremediation of co-contaminated environments have focussed on the use of metal-resistant bacteria (cell and gene bioaugmentation), treatment amendments, clay minerals and chelating agents to reduce bioavailable heavy metal concentrations. Phytoremediation has also shown promise as an emerging alternative clean-up technology for co-contaminated environments. However, despite various investigations, in both aerobic and anaerobic systems, demonstrating that metal toxicity hampers the biodegradation of the organic component, a paucity of information exists in this area of research. Therefore, in this review, we discuss the problems associated with the degradation of chlorinated organics in co-contaminated environments, owing to metal toxicity and shed light on possible improvement strategies for effective bioremediation of sites co-contaminated with chlorinated organic compounds and heavy metals.

  5. Bioavailability of Heavy Metals in Soil: Impact on Microbial Biodegradation of Organic Compounds and Possible Improvement Strategies

    Directory of Open Access Journals (Sweden)

    Balakrishna Pillay

    2013-05-01

    Full Text Available Co-contamination of the environment with toxic chlorinated organic and heavy metal pollutants is one of the major problems facing industrialized nations today. Heavy metals may inhibit biodegradation of chlorinated organics by interacting with enzymes directly involved in biodegradation or those involved in general metabolism. Predictions of metal toxicity effects on organic pollutant biodegradation in co-contaminated soil and water environments is difficult since heavy metals may be present in a variety of chemical and physical forms. Recent advances in bioremediation of co-contaminated environments have focussed on the use of metal-resistant bacteria (cell and gene bioaugmentation, treatment amendments, clay minerals and chelating agents to reduce bioavailable heavy metal concentrations. Phytoremediation has also shown promise as an emerging alternative clean-up technology for co-contaminated environments. However, despite various investigations, in both aerobic and anaerobic systems, demonstrating that metal toxicity hampers the biodegradation of the organic component, a paucity of information exists in this area of research. Therefore, in this review, we discuss the problems associated with the degradation of chlorinated organics in co-contaminated environments, owing to metal toxicity and shed light on possible improvement strategies for effective bioremediation of sites co-contaminated with chlorinated organic compounds and heavy metals.

  6. Bioavailability of Heavy Metals in Soil: Impact on Microbial Biodegradation of Organic Compounds and Possible Improvement Strategies

    Science.gov (United States)

    Olaniran, Ademola O.; Balgobind, Adhika; Pillay, Balakrishna

    2013-01-01

    Co-contamination of the environment with toxic chlorinated organic and heavy metal pollutants is one of the major problems facing industrialized nations today. Heavy metals may inhibit biodegradation of chlorinated organics by interacting with enzymes directly involved in biodegradation or those involved in general metabolism. Predictions of metal toxicity effects on organic pollutant biodegradation in co-contaminated soil and water environments is difficult since heavy metals may be present in a variety of chemical and physical forms. Recent advances in bioremediation of co-contaminated environments have focussed on the use of metal-resistant bacteria (cell and gene bioaugmentation), treatment amendments, clay minerals and chelating agents to reduce bioavailable heavy metal concentrations. Phytoremediation has also shown promise as an emerging alternative clean-up technology for co-contaminated environments. However, despite various investigations, in both aerobic and anaerobic systems, demonstrating that metal toxicity hampers the biodegradation of the organic component, a paucity of information exists in this area of research. Therefore, in this review, we discuss the problems associated with the degradation of chlorinated organics in co-contaminated environments, owing to metal toxicity and shed light on possible improvement strategies for effective bioremediation of sites co-contaminated with chlorinated organic compounds and heavy metals. PMID:23676353

  7. Advances in paediatrics in 2016: current practices and challenges in allergy, autoimmune diseases, cardiology, endocrinology, gastroenterology, infectious diseases, neonatology, nephrology, neurology, nutrition, pulmonology.

    Science.gov (United States)

    Caffarelli, Carlo; Santamaria, Francesca; Di Mauro, Dora; Mastrorilli, Carla; Montella, Silvia; Bernasconi, Sergio

    2017-09-16

    This review reports main progresses in various pediatric issues published in Italian Journal of Pediatrics and in international journals in 2016. New insights in clinical features or complications of several disorders may be useful for our better understanding. They comprise severe asthma, changing features of lupus erythematosus from birth to adolescence, celiac disease, functional gastrointestinal disorders, Moebius syndrome, recurrent pneumonia. Risk factors for congenital heart defects, Kawasaki disease have been widely investigated. New diagnostic tools are available for ascertaining brucellosis, celiac disease and viral infections. The usefulness of aCGH as first-tier test is confirmed in patients with neurodevelopmental disorders. Novel information have been provided on the safety of milk for infants. Recent advances in the treatment of common disorders, including neonatal respiratory distress syndrome, hypo-glycemia in newborns, atopic dermatitis, constipation, cyclic vomiting syndrome, nephrotic syndrome, diabetes mellitus, regurgitation, short stature, secretions in children with cerebral palsy have been reported. Antipyretics treatment has been updated by national guidelines and studies have excluded side effects (e.g. asthma risk during acetaminophen therapy). Vaccinations are a painful event and several options are reported to prevent this pain. Adverse effects due to metabolic abnormalities are reported for second generation antipsychotic drugs.

  8. The European KIDSCREEN approach to measure quality of life and well-being in children: development, current application, and future advances.

    Science.gov (United States)

    Ravens-Sieberer, Ulrike; Herdman, Michael; Devine, Janine; Otto, Christiane; Bullinger, Monika; Rose, Matthias; Klasen, Fionna

    2014-04-01

    The KIDSCREEN questionnaires were developed by a collaborative effort of European pediatric researchers for use in epidemiologic public health surveys, clinical intervention studies, and research projects. The article gives an overview of the development of the tool, summarizes its extensive applications in Europe, and describes the development of a new computerized adaptive test (KIDS-CAT) based on KIDSCREEN experiences. The KIDSCREEN versions (self-report and proxy versions with 52, 27, and 10 items) were simultaneously developed in 13 different European countries to warrant cross-cultural applicability, using methods based on classical test theory (CTT: descriptive statistics, CFA and MAP, internal consistency, retest reliability measures) and item response theory (IRT: Rasch modeling, DIF analyses, etc.). The KIDS-CAT was developed (in cooperation with the US pediatric PROMIS project) based on archival data of European KIDSCREEN health surveys using IRT more extensively (IRC). Research has shown that the KIDSCREEN is a reliable, valid, sensitive, and conceptually/linguistically appropriate QoL measure in 38 countries/languages by now. European and national norm data are available. New insights from KIDSCREEN studies stimulate pediatric health care. Based on KIDSCREEN, the Kids-CAT promises to facilitate a very efficient, precise, as well as reliable and valid assessment of QoL. The KIDSCREEN has standardized QoL measurement in Europe in children as a valid and cross-cultural comparable tool. The Kids-CAT has the potential to further advance pediatric health measurement and care via Internet application.

  9. Current practices in the management of adverse events associated with targeted therapies for advanced renal cell carcinoma: a national survey of oncologists.

    Science.gov (United States)

    Ruiz, Janelle Nicole; Belum, Viswanath Reddy; Creel, Patricia; Cohn, Allen; Ewer, Michael; Lacouture, Mario E

    2014-10-01

    Oncologists treating patients with targeted therapies encounter adverse events (AEs) that pose management challenges, lead to dosing inconsistencies, and impact patient quality of life. Oncologists' practices and attitudes in the management of targeted therapy-related AEs in patients with renal cell carcinoma (RCC) are poorly understood. We sought to identify unmet needs associated with AE management and understand oncologists' treatment optimization strategies. A 24-item online survey was administered in August 2012 to 119 US oncologists treating patients with advanced RCC. The survey solicited responses regarding demographics, practice settings, AE management practice patterns and beliefs, treatment barriers, and patient education. Respondents indicated that between 25% and 50% of patients require dose modification/discontinuation because of AEs. The greatest barrier to optimizing treatment for RCC is the unpredictability of patient responses to treatment (43%). Most respondents (78%) discuss AE management with patients, but only a minority of them proactively reach out to patients (46%). Most practitioners (70%) refer patients to nononcology specialists when faced with unfamiliar AEs, although finding interested physicians (43%) and time constraints (40%) were the most commonly cited barriers to consulting with other specialties. Results suggest that many patients require dose modification/discontinuation because of AEs and that nononcologists are a frequently utilized resource to manage these events. There is a need for predictive drug toxicity markers to establish counseling and prevention, along with opportunities for increased education on supportive care techniques to maintain health-related quality of life and consistent dosing. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Biologic Treatments for Sports Injuries II Think Tank-Current Concepts, Future Research, and Barriers to Advancement, Part 1: Biologics Overview, Ligament Injury, Tendinopathy.

    Science.gov (United States)

    LaPrade, Robert F; Geeslin, Andrew G; Murray, Iain R; Musahl, Volker; Zlotnicki, Jason P; Petrigliano, Frank; Mann, Barton J

    2016-12-01

    Biologic therapies, including stem cells, platelet-rich plasma, growth factors, and other biologically active adjuncts, have recently received increased attention in the basic science and clinical literature. At the 2015 AOSSM Biologics II Think Tank held in Colorado Springs, Colorado, a group of orthopaedic surgeons, basic scientists, veterinarians, and other investigators gathered to review the state of the science for biologics and barriers to implementation of biologics for the treatment of sports medicine injuries. This series of current concepts reviews reports the summary of the scientific presentations, roundtable discussions, and recommendations from this think tank. © 2016 The Author(s).

  11. Advancing Implementation of Evidence-Based Public Health in China: An Assessment of the Current Situation and Suggestions for Developing Regions

    Directory of Open Access Journals (Sweden)

    Jianwei Shi

    2016-01-01

    Full Text Available Objective. Existing research shows a serious scarcity of EBPH practice in China and other developing regions; as an exploratory study, this study aimed to assess the current EBPH implementation status in Shanghai of China qualitatively. Methods. Using semistructured key informant interviews, we examined the status of and impediments to the lagging EBPH in China. Data were analyzed based on the Consolidated Framework for Implementation Research (CFIR. Results. Chinese public health practitioners knew more about evidence-based medicine but less about EBPH. The situation was worse in community healthcare centers. Participants perceived that evidence sources were limited and the quality of evidence was low. Concerning the inner setting factors, the structural characteristics, networks and communications, implementation climate, and leadership engagement were confronted with many problems. Among the outer setting factors, external government policies and incentives and low patient compliance were the key problems. Additionally, public health practitioners in Shanghai lacked sufficient awareness of EBPH. Furthermore, the current project-based EBPH lacks a systematic implementation system. Conclusions. Existing practical perspectives on EBPH indicate a lag in the advocacy of this new ideology in China. It would be advisable for healthcare institutions to take the initiative to explore feasible and multiple methods of EBPH promotion.

  12. Degradation of oxo-biodegradable plastic by Pleurotus ostreatus.

    Directory of Open Access Journals (Sweden)

    José Maria Rodrigues da Luz

    Full Text Available Growing concerns regarding the impact of the accumulation of plastic waste over several decades on the environmental have led to the development of biodegradable plastic. These plastics can be degraded by microorganisms and absorbed by the environment and are therefore gaining public support as a possible alternative to petroleum-derived plastics. Among the developed biodegradable plastics, oxo-biodegradable polymers have been used to produce plastic bags. Exposure of this waste plastic to ultraviolet light (UV or heat can lead to breakage of the polymer chains in the plastic, and the resulting compounds are easily degraded by microorganisms. However, few studies have characterized the microbial degradation of oxo-biodegradable plastics. In this study, we tested the capability of Pleurotus ostreatus to degrade oxo-biodegradable (D2W plastic without prior physical treatment, such as exposure to UV or thermal heating. After 45 d of incubation in substrate-containing plastic bags, the oxo-biodegradable plastic, which is commonly used in supermarkets, developed cracks and small holes in the plastic surface as a result of the formation of hydroxyl groups and carbon-oxygen bonds. These alterations may be due to laccase activity. Furthermore, we observed the degradation of the dye found in these bags as well as mushroom formation. Thus, P. ostreatus degrades oxo-biodegradable plastics and produces mushrooms using this plastic as substrate.

  13. Biodegradation of polyethylene by the thermophilic bacterium Brevibacillus borstelensis.

    Science.gov (United States)

    Hadad, D; Geresh, S; Sivan, A

    2005-01-01

    To select a polyethylene-degrading micro-organism and to study the factors affecting its biodegrading activity. A thermophilic bacterium Brevibaccillus borstelensis strain 707 (isolated from soil) utilized branched low-density polyethylene as the sole carbon source and degraded it. Incubation of polyethylene with B. borstelensis (30 days, 50 degrees C) reduced its gravimetric and molecular weights by 11 and 30% respectively. Brevibaccillus borstelensis also degraded polyethylene in the presence of mannitol. Biodegradation of u.v. photo-oxidized polyethylene increased with increasing irradiation time. Fourier Transform Infra-Red (FTIR) analysis of photo-oxidized polyethylene revealed a reduction in carbonyl groups after incubation with the bacteria. This study demonstrates that polyethylene--considered to be inert--can be biodegraded if the right microbial strain is isolated. Enrichment culture methods were effective for isolating a thermophilic bacterium capable of utilizing polyethylene as the sole carbon and energy source. Maximal biodegradation was obtained in combination with photo-oxidation, which showed that carbonyl residues formed by photo-oxidation play a role in biodegradation. Brevibaccillus borstelensis also degraded the CH2 backbone of nonirradiated polyethylene. Biodegradation of polyethylene by a single bacterial strain contributes to our understanding of the process and the factors affecting polyethylene biodegradation.

  14. Degradation of oxo-biodegradable plastic by Pleurotus ostreatus.

    Science.gov (United States)

    da Luz, José Maria Rodrigues; Paes, Sirlaine Albino; Nunes, Mateus Dias; da Silva, Marliane de Cássia Soares; Kasuya, Maria Catarina Megumi

    2013-01-01

    Growing concerns regarding the impact of the accumulation of plastic waste over several decades on the environmental have led to the development of biodegradable plastic. These plastics can be degraded by microorganisms and absorbed by the environment and are therefore gaining public support as a possible alternative to petroleum-derived plastics. Among the developed biodegradable plastics, oxo-biodegradable polymers have been used to produce plastic bags. Exposure of this waste plastic to ultraviolet light (UV) or heat can lead to breakage of the polymer chains in the plastic, and the resulting compounds are easily degraded by microorganisms. However, few studies have characterized the microbial degradation of oxo-biodegradable plastics. In this study, we tested the capability of Pleurotus ostreatus to degrade oxo-biodegradable (D2W) plastic without prior physical treatment, such as exposure to UV or thermal heating. After 45 d of incubation in substrate-containing plastic bags, the oxo-biodegradable plastic, which is commonly used in supermarkets, developed cracks and small holes in the plastic surface as a result of the formation of hydroxyl groups and carbon-oxygen bonds. These alterations may be due to laccase activity. Furthermore, we observed the degradation of the dye found in these bags as well as mushroom formation. Thus, P. ostreatus degrades oxo-biodegradable plastics and produces mushrooms using this plastic as substrate.

  15. High-frequency, long-duration water sampling in acid mine drainage studies: a short review of current methods and recent advances in automated water samplers

    Science.gov (United States)

    Chapin, Thomas

    2015-01-01

    Hand-collected grab samples are the most common water sampling method but using grab sampling to monitor temporally variable aquatic processes such as diel metal cycling or episodic events is rarely feasible or cost-effective. Currently available automated samplers are a proven, widely used technology and typically collect up to 24 samples during a deployment. However, these automated samplers are not well suited for long-term sampling in remote areas or in freezing conditions. There is a critical need for low-cost, long-duration, high-frequency water sampling technology to improve our understanding of the geochemical response to temporally variable processes. This review article will examine recent developments in automated water sampler technology and utilize selected field data from acid mine drainage studies to illustrate the utility of high-frequency, long-duration water sampling.

  16. Advancement of the Eddy Current Testing using neural network technique. Development of 3-D finite element analysis sytem of elctro-magnetic field

    International Nuclear Information System (INIS)

    Sakai, Takayuki; Soneda, Naoki

    1994-01-01

    In PWR plants, an automatic recognition system of Eddy Current Testing (ECT) signals of steam generator tubes are strongly required to reduce inspectors' labor and to improve the reliability of the testing. Although the neural-network technique is very promising for this kind of system, it is necessary to evaluate its applicability to ECT signals throughly, where a database of the relationship of the defects and ECT signals plays a very important role. In this paper, a three dimensional finite element analysis system of electromagnetic field, which consists of an FEM code and pre/post processor, is developed to generate a database of ECT signals. T-Ω method and the edge element are employed in the FEM code to reduce the required computer memory. The code is verified through some comparisons with experiments and other calculations. (author)

  17. Polydioxanone biodegradable stent placement in a canine urethral model: analysis of inflammatory reaction and biodegradation.

    Science.gov (United States)

    Park, Jung-Hoon; Song, Ho-Young; Shin, Ji Hoon; Kim, Jin Hyoung; Jun, Eun Jung; Cho, Young Chul; Kim, Soo Hwan; Park, Jihong

    2014-08-01

    To investigate the inflammatory reaction and perform quantitative analysis of biodegradation after placement of a polydioxanone (PDO) biodegradable stent in a canine urethral model. PDO biodegradable stents were placed in the proximal and distal urethra of nine male mongrel dogs. The dogs were euthanized 4 weeks (group A; n = 3), 8 weeks (group B; n = 3), or 12 weeks (group C; n = 3) after stent placement. The luminal diameter of the stent-implanted urethra was assessed by follow-up retrograde urethrography, and histologic findings were obtained after the dogs were killed. Stents were removed after euthanasia, and their surface morphology and molecular weight were evaluated. Hematologic examination was performed to evaluate inflammatory reaction. Stent placement was technically successful in all dogs. The average luminal diameter gradually decreased. The average number of epithelial layers (2.93 vs 4.42; P stents were completely decomposed. An experimental study in a canine urethral model has demonstrated acceptable inflammatory reaction with gradually increasing granulation tissue but no luminal obstruction within 12 weeks. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

  18. Biodegradable and biocompatible polymers for tissue engineering application: a review.

    Science.gov (United States)

    Asghari, Fatemeh; Samiei, Mohammad; Adibkia, Khosro; Akbarzadeh, Abolfazl; Davaran, Soodabeh

    2017-03-01

    Since so many years ago, tissue damages that are caused owing to various reasons attract scientists' attention to find a practical way to treat. In this regard, many studies were conducted. Nano scientists also suggested some ways and the newest one is called tissue engineering. They use biodegradable polymers in order to replace damaged structures in tissues to make it practical. Biodegradable polymers are dominant scaffolding materials in tissue engineering field. In this review, we explained about biodegradable polymers and their application as scaffolds.

  19. In vitro investigations of a novel wound dressing concept based on biodegradable polyurethane

    International Nuclear Information System (INIS)

    Rottmar, Markus; Richter, Michael; Mäder, Xenia; Grieder, Kathrin; Bruinink, Arie; Nuss, Katja; Karol, Agnieszka; Rechenberg, Brigitte von; Zimmermann, Erika; Buser, Stephan; Dobmann, Andreas; Blume, Jessica

    2015-01-01

    Non-healing and partially healing wounds are an important problem not only for the patient but also for the public health care system. Current treatment solutions are far from optimal regarding the chosen material properties as well as price and source. Biodegradable polyurethane (PUR) scaffolds have shown great promise for in vivo tissue engineering approaches, but accomplishment of the goal of scaffold degradation and new tissue formation developing in parallel has not been observed so far in skin wound repair. In this study, the mechanical properties and degradation behavior as well as the biocompatibility of a low-cost synthetic, pathogen-free, biocompatible and biodegradable extracellular matrix mimicking a PUR scaffold was evaluated in vitro. The novel PUR scaffolds were found to meet all the requirements for optimal scaffolds and wound dressings. These three-dimensional scaffolds are soft, highly porous, and form-stable and can be easily cut into any shape desired. All the material formulations investigated were found to be nontoxic. One formulation was able to be defined that supported both good fibroblast cell attachment and cell proliferation to colonize the scaffold. Tunable biodegradation velocity of the materials could be observed, and the results additionally indicated that calcium plays a crucial role in PUR degradation. Our results suggest that the PUR materials evaluated in this study are promising candidates for next-generation wound treatment systems and support the concept of using foam scaffolds for improved in vivo tissue engineering and regeneration. (focus issue paper)

  20. Theoretical Insight into the Biodegradation of Solitary Oil Microdroplets Moving through a Water Column.

    Science.gov (United States)

    Kapellos, George E; Paraskeva, Christakis A; Kalogerakis, Nicolas; Doyle, Patrick S

    2018-02-12

    In the aftermath of oil spills in the sea, clouds of droplets drift into the seawater column and are carried away by sea currents. The fate of the drifting droplets is determined by natural attenuation processes, mainly dissolution into the seawater and biodegradation by oil-degrading microbial communities. Specifically, microbes have developed three fundamental strategies for accessing and assimilating oily substrates. Depending on their affinity for the oily phase and ability to proliferate in multicellular structures, microbes might either attach to the oil surface and directly uptake compounds from the oily phase, or grow suspended in the aqueous phase consuming solubilized oil, or form three-dimensional biofilms over the oil-water interface. In this work, a compound particle model that accounts for all three microbial strategies is developed for the biodegradation of solitary oil microdroplets moving through a water column. Under a set of educated hypotheses, the hydrodynamics and solute transport problems are amenable to analytical solutions and a closed-form correlation is established for the overall dissolution rate as a function of the Thiele modulus, the Biot number and other key parameters. Moreover, two coupled ordinary differential equations are formulated for the evolution of the particle size and used to investigate the impact of the dissolution and biodegradation processes on the droplet shrinking rate.

  1. In vitro investigations of a novel wound dressing concept based on biodegradable polyurethane

    Science.gov (United States)

    Rottmar, Markus; Richter, Michael; Mäder, Xenia; Grieder, Kathrin; Nuss, Katja; Karol, Agnieszka; von Rechenberg, Brigitte; Zimmermann, Erika; Buser, Stephan; Dobmann, Andreas; Blume, Jessica; Bruinink, Arie

    2015-06-01

    Non-healing and partially healing wounds are an important problem not only for the patient but also for the public health care system. Current treatment solutions are far from optimal regarding the chosen material properties as well as price and source. Biodegradable polyurethane (PUR) scaffolds have shown great promise for in vivo tissue engineering approaches, but accomplishment of the goal of scaffold degradation and new tissue formation developing in parallel has not been observed so far in skin wound repair. In this study, the mechanical properties and degradation behavior as well as the biocompatibility of a low-cost synthetic, pathogen-free, biocompatible and biodegradable extracellular matrix mimicking a PUR scaffold was evaluated in vitro. The novel PUR scaffolds were found to meet all the requirements for optimal scaffolds and wound dressings. These three-dimensional scaffolds are soft, highly porous, and form-stable and can be easily cut into any shape desired. All the material formulations investigated were found to be nontoxic. One formulation was able to be defined that supported both good fibroblast cell attachment and cell proliferation to colonize the scaffold. Tunable biodegradation velocity of the materials could be observed, and the results additionally indicated that calcium plays a crucial role in PUR degradation. Our results suggest that the PUR materials evaluated in this study are promising candidates for next-generation wound treatment systems and support the concept of using foam scaffolds for improved in vivo tissue engineering and regeneration.

  2. Biodegradable Poly(polyol sebacate) Polymers

    Science.gov (United States)

    Bruggeman, Joost P.; de Bruin, Berend-Jan; Bettinger, Christopher J.; Langer, Robert

    2010-01-01

    We have developed a family of synthetic biodegradable polymers that are composed of structural units endogenous to the human metabolism, designated poly(polyol sebacates) (PPS) polymers. Material properties of PPS polymers can be tuned by altering the polyol monomer and reacting stiochiometric ratio of sebacic acid. These thermoset networks exhibited tensile Young’s moduli ranging from 0.37 ± 0.08 to 378 ± 33 MPa with maximum elongations at break from 10.90 ± 1.37 to 205.16 ± 55.76%, and glass-transition temperatures ranged from ~7 to 46 °C. In vitro degradation under physiological conditions was slower than in vivo degradation rates observed for some PPS polymers. PPS polymers demonstrated similar in vitro and in vivo biocompatibility compared to poly(L-lactic-co-glycolic acid) (PLGA). PMID:18824260

  3. Biodegradable thermogelling polymers: working towards clinical applications.

    Science.gov (United States)

    Dou, Qing Qing; Liow, Sing Shy; Ye, Enyi; Lakshminarayanan, Rajamani; Loh, Xian Jun

    2014-07-01

    As society ages, aging medical problems such as organ damage or failure among senior citizens increases, raising the demand for organ repair technologies. Synthetic materials have been developed and applied in various parts of human body to meet the biomedical needs. Hydrogels, in particular, have found extensive applications as wound healing, drug delivery and controlled release, and scaffold materials in the human body. The development of the next generation of soft hydrogel biomaterials focuses on facile synthetic methods, efficacy of treatment, and tunable multi-functionalities for applications. Supramolecular 3D entities are highly attractive materials for biomedical application. They are assembled by modules via various non-covalent bonds (hydrogen bonds, p-p stacking and/or van der Waals interactions). Biodegradable thermogels are a class of such supramolecular assembled materials. Their use as soft biomaterials and their related applications are described in this Review. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Partial Discharge Degradation of Several Biodegradable Polymers

    Science.gov (United States)

    Fuse, Norikazu; Fujita, Shinjiro; Hirai, Naoshi; Tanaka, Toshikatsu; Kozako, Masahiro; Kohtoh, Masanori; Okabe, Shigemitsu; Ohki, Yoshimichi

    Partial discharge (PD) resistance was examined by applying a constant voltage for four kinds of biodegradable polymers, i.e. poly-L-lactic acid (PLLA), polyethylene terephthalate succinate (PETS), poly ε-caprolactone butylene succinate (PCL-BS), and polybutylene succinate (PBS), and the results were compared with those of low density polyethylene (LDPE) and crosslinked low density polyethylene (XLPE). The PD resistance is determined by the erosion depth and the surface roughness caused by PDs, and is ranked as LDPE ≅ XLPE > PLLA ≅ PETS > PBS > PCL-BS. This means that the sample with a lower permittivity has better PD resistance. Furthermore, observations of the sample surface by a polarization microscope and a laser confocal one reveal that crystalline regions with spherulites are more resistant to PDs than amorphous regions. Therefore, good PD resistance can be achieved by the sample with a high crystallinity and a low permittivity.

  5. Gasoline biodegradation in different soil microcosms

    Directory of Open Access Journals (Sweden)

    Cunha Cláudia Duarte da

    2000-01-01

    Full Text Available The objective of this study was to evaluate gasoline biodegradation in batch soil microcosms. Microorganisms able to grow in the presence of gasoline were isolated from soil. Several treatment systems were performed using both isolated strains and Pseudomonas putida obtained from a culture collection. The treatment system using only autochthonous microflora (system 1 presented an average value of degradation of 50%. The association of Pseudomonas putida, Burkholderia cepacia, Pseudomonas alcaligenes and the native soil microflora (system 13 presented significant percentage of removal of n-undecane (88.7, n-dodecane (61.3 and n-tridecane (66.7. According to these results, systems 1 and 13 revealed considerable potential for application in bioremediation treatments.

  6. Biodegradable polymeric nanocarriers for pulmonary drug delivery.

    Science.gov (United States)

    Rytting, Erik; Nguyen, Juliane; Wang, Xiaoying; Kissel, Thomas

    2008-06-01

    Pulmonary drug delivery is attractive for both local and systemic drug delivery as a non-invasive route that provides a large surface area, thin epithelial barrier, high blood flow and the avoidance of first-pass metabolism. Nanoparticles can be designed to have several advantages for controlled and targeted drug delivery, including controlled deposition, sustained release, reduced dosing frequency, as well as an appropriate size for avoiding alveolar macrophage clearance or promoting transepithelial transport. This review focuses on the development and application of biodegradable polymers to nanocarrier-based strategies for the delivery of drugs, peptides, proteins, genes, siRNA and vaccines by the pulmonary route. The selection of natural or synthetic materials is important in designing particles or nanoparticle clusters with the desired characteristics, such as biocompatibility, size, charge, drug release and polymer degradation rate.

  7. Biodegradation of concrete intended for their decontamination

    International Nuclear Information System (INIS)

    Jestin, A.

    2005-05-01

    The decontamination of sub-structural materials represents a stake of high importance because of the high volume generated. It is agreed then to propose efficient and effective processes. The process of bio-decontamination of the hydraulic binders leans on the mechanisms of biodegradation of concretes, phenomenon characterized in the 40's by an indirect attack of the material by acids stem from the microbial metabolism: sulphuric acid (produced by Thiobacillus), nitric acid (produced by Nitrosomonas and Nitrobacter) and organic acids (produced by fungi). The principle of the bio-decontamination process is to apply those microorganisms on the surface of the contaminated material, in order to damage its surface and to retrieve the radionuclides. One of the multiple approaches of the process is the use of a bio-gel that makes possible the micro-organisms application. (author)

  8. Optimizing BTEX biodegradation under denitrifying conditions

    International Nuclear Information System (INIS)

    Hutchins, S.R.

    1991-01-01

    Leaking underground storage tanks are a major source of ground water contamination by petroleum hydrocarbons. Gasoline and other fuels contain benzene, toluene, ethylbenzene, and xylenes (collectively known as BTEX), which are hazardous compounds, regulated by the U.S. Environmental Protection Agency (EPA). Laboratory tests were conducted to determine optimum conditions for benzene, toluene, ethylbenzene, and xylene (collectively known as BTEX) biodegradation by aquifer microorganisms under denitrifying conditions. Microcosms, constructed with aquifer samples from Traverse City, Michigan, were amended with selected concentrations of nutrients and one or more hydrocarbons. Toluene, ethylbenzene, m-xylene, and p-xylene, were degraded to below 5 micrograms/L when present as sole source substrates; stoichiometric calculations indicated that nitrate removal was sufficient to account for 70 to 80% of the compounds being mineralized. o-Xylene was recalcitrant when present as a sole source substrate, but was slowly degraded in the presence of the other hydrocarbons. Benzene was not degraded within one year, regardless of whether it was available as a sole source substrate or in combination with toluene, phenol, or catechol. Pre-exposure to low levels of BTEX and nutrients had variable effects, as did the addition of different concentrations of ammonia and phosphate. Nitrate concentrations as high as 500 mg/L NO3-N were slightly inhibitory. These data indicate that nitrate-mediated biodegradation of BTEX at Traverse City can occur under a variety of environmental conditions with rates relatively independent of nutrient concentrations. However, the data reaffirm that benzene is recalcitrant under strictly anaerobic conditions in these samples

  9. Biodegradation of carbon nanohorns in macrophage cells

    Science.gov (United States)

    Zhang, Minfang; Yang, Mei; Bussy, Cyrill; Iijima, Sumio; Kostarelos, Kostas; Yudasaka, Masako

    2015-02-01

    With the rapid developments in the medical applications of carbon nanomaterials such as carbon nanohorns (CNHs), carbon nanotubes, and graphene based nanomaterials, understanding the long-term fate, health impact, excretion, and degradation of these materials has become crucial. Herein, the in vitro biodegradation of CNHs was determined using a non-cellular enzymatic oxidation method and two types of macrophage cell lines. Approximately 60% of the CNHs was degraded within 24 h in a phosphate buffer solution containing myeloperoxidase. Furthermore, approximately 30% of the CNHs was degraded by both RAW 264.7 and THP-1 macrophage cells within 9 days. Inflammation markers such as pro-inflammatory cytokines interleukin 6 and tumor necrosis factor α were not induced by exposure to CNHs. However, reactive oxygen species were generated by the macrophage cells after uptake of CNHs, suggesting that these species were actively involved in the degradation of the nanomaterials rather than in an inflammatory pathway induction.With the rapid developments in the medical applications of carbon nanomaterials such as carbon nanohorns (CNHs), carbon nanotubes, and graphene based nanomaterials, understanding the long-term fate, health impact, excretion, and degradation of these materials has become crucial. Herein, the in vitro biodegradation of CNHs was determined using a non-cellular enzymatic oxidation method and two types of macrophage cell lines. Approximately 60% of the CNHs was degraded within 24 h in a phosphate buffer solution containing myeloperoxidase. Furthermore, approximately 30% of the CNHs was degraded by both RAW 264.7 and THP-1 macrophage cells within 9 days. Inflammation markers such as pro-inflammatory cytokines interleukin 6 and tumor necrosis factor α were not induced by exposure to CNHs. However, reactive oxygen species were generated by the macrophage cells after uptake of CNHs, suggesting that these species were actively involved in the degradation of the

  10. Antibacterial biodegradable Mg-Ag alloys

    Directory of Open Access Journals (Sweden)

    D Tie

    2013-06-01

    Full Text Available The use of magnesium alloys as degradable metals for biomedical applications is a topic of ongoing research and the demand for multifunctional materials is increasing. Hence, binary Mg-Ag alloys were designed as implant materials to combine the favourable properties of magnesium with the well-known antibacterial property of silver. In this study, three Mg-Ag alloys, Mg2Ag, Mg4Ag and Mg6Ag that contain 1.87 %, 3.82 % and 6.00 % silver by weight, respectively, were cast and processed with solution (T4 and aging (T6 heat treatment.The metallurgical analysis and phase identification showed that all alloys contained Mg4Ag as the dominant β phase. After heat treatment, the mechanical properties of all Mg-Ag alloys were significantly improved and the corrosion rate was also significantly reduced, due to presence of silver. Mg(OH2 and MgO present the main magnesium corrosion products, while AgCl was found as the corresponding primary silver corrosion product. Immersion tests, under cell culture conditions, demonstrated that the silver content did not significantly shift the pH and magnesium ion release. In vitro tests, with both primary osteoblasts and cell lines (MG63, RAW 264.7, revealed that Mg-Ag alloys show negligible cytotoxicity and sound cytocompatibility. Antibacterial assays, performed in a dynamic bioreactor system, proved that the alloys reduce the viability of two common pathogenic bacteria, Staphylococcus aureus (DSMZ 20231 and Staphylococcus epidermidis (DSMZ 3269, and the results showed that the killing rate of the alloys against tested bacteria exceeded 90%. In summary, biodegradable Mg-Ag alloys are cytocompatible materials with adjustable mechanical and corrosion properties and show promising antibacterial activity, which indicates their potential as antibacterial biodegradable implant materials.

  11. Biodegradability relationships among propylene glycol substances in the Organization for Economic Cooperation and Development ready- and seawater biodegradability tests.

    Science.gov (United States)

    West, Robert J; Davis, John W; Pottenger, Lynn H; Banton, Marcy I; Graham, Cynthia

    2007-05-01

    Eight propylene glycol substances, ranging from 1,2-propanediol to a poly(propylene glycol) (PPG) having number-average molecular weight (M(n)) of 2,700 (i.e., PPG 2700), were evaluated in the Organization for Economic Cooperation and Development (OECD) ready- and seawater biodegradability tests. Uniformity in test parameters, such as inoculum source/density and test substance concentrations, combined with frequent measurements of O2 consumption and CO2 evolution, revealed unexpected biodegradability trends across this family of substances. Biodegradability in both tests decreased with increased number of oxy-propylene repeating units (n = 1, 2, 3, 4) of the oligomeric propylene glycols (PGs). However, this trend was reversed for the PPG polymers, and increased biodegradability was observed with increases of average n to seven, 17, and 34 (M(n) = 425, 1,000, and 2,000, respectively). This relationship between molecular weight and biodegradability was reversed again when average n was incremented from 34 (PPG 2000) to 46 (PPG 2700). Six of the tested substances (n = 1, 2, 3, 7, 17, and 34) met the OECD-specified criteria for "ready biodegradability," whereas the tetrapropylene glycol (n = 4) and PPG 2700 substances failed to meet these criteria. Biodegradation half-lives for these eight substances ranged from 3.8 d (PPG 2000) to 33.2 d (PPG 2700) in the ready test, and from 13.6 (PG) to 410 d (PPG 2700) in seawater. Biodegradation half-lives in seawater were significantly correlated with half-lives determined in the ready test. However, half-lives in both tests were correlated poorly with molecular weight, water solubility, and log K(ow). It is speculated that the molecular conformation of these substances, perhaps more so than these other physicochemical properties, has an important role in influencing biodegradability of the propylene glycol substances.

  12. Compounds interaction on biodegradation of toluene and methyl ...

    African Journals Online (AJOL)

    MEK) mixtures in a composite bead biofilter was investigated. The biodegradation rate of two compounds in the exponential growth phase and stationary phase for the single compound and two compounds mixing systems was determined.

  13. Anaerobic biodegradation of lipids of the marine microalga Nannochloropsis salina

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Grossi, V.; Blokker, P.

    2001-01-01

    In order to determine the susceptibility to anaerobic biodegradation of the different lipid biomarkers present in a marine microalga containing algaenan, portions of one large batch of cultured Nannochloropsis salina (Eustigmatophyceae) were incubated in anoxic sediment slurries for various times.

  14. Biodegradation of waste PET based copolyesters in thermophilic anaerobic sludge

    Czech Academy of Sciences Publication Activity Database

    Hermanová, S.; Šmejkalová, P.; Merna, J.; Zarevúcka, Marie

    2015-01-01

    Roč. 111, Jan (2015), s. 176-184 ISSN 0141-3910 Institutional support: RVO:61388963 Keywords : poly(ethylene terephthalate) * copolymers * sludge * biodegradation * hydrolysis * waste Subject RIV: EI - Biotechnology ; Bionics Impact factor: 3.120, year: 2015

  15. Toward biodegradable nanogel star polymers via organocatalytic ROP.

    Science.gov (United States)

    Appel, Eric A; Lee, Victor Y; Nguyen, Timothy T; McNeil, Melanie; Nederberg, Frederik; Hedrick, James L; Swope, William C; Rice, Jullia E; Miller, Robert D; Sly, Joseph

    2012-06-21

    Organocatalytic ring opening polymerization (OROP) is used to effect the rapid, scalable, room temperature formation of size-controlled, highly uniform, polyvalent, nanogel star polymer nanoparticles of biodegradable composition.

  16. Organic pollutant loading and biodegradability of firefighting foam

    Science.gov (United States)

    Zhang, Xian-Zhong; Bao, Zhi-ming; Hu, Cheng; Li-Shuai, Jing; Chen, Yang

    2017-11-01

    Firefighting foam has been widely used as the high-performance extinguishing agent in extinguishing the liquid poor fire. It was concerned for its environmental impacts due to its massive usage. In this study, the organic loading level and the biodegradability of 18 firefighting foams commonly used in China were evaluated and compared. The COD and TOC of firefighting foam concentrates are extremely high. Furthermore, those of foam solutions are also much higher than regular wastewater. The COD/TOC ratio of synthetic foams are higher than protein foams. The 28-day biodegradation rates of 18 firefighting foams are all over 60%, indicating that they are all ready biodegradable. Protein foams (P, FP and FFFP) have the higher organic loading and lower 28-day biodegradation rates compared to the synthetic foams (Class A foam, AFFF and S). The short and long-term impact of protein foams on the environment are larger than synthetic foams.

  17. COLUMN STUDIES ON BTEX BIODEGRADATION UNDER MICROAEROPHILIC AND DENITRIFYING CONDITIONS

    Science.gov (United States)

    Two column tests were conducted using aquifer material to simulate the nitrate field demonstration project carried out earlier at Traverse City, Michigan. The objectives were to better define the effect nitrate addition had on biodegradation of benzene, toluene, ethylbenzene, xyl...

  18. Biodegradation of Endosulfan by Mixed Bacteria Culture Strains

    African Journals Online (AJOL)

    Nwokem et al.

    Aeruginosa and Staphylococcus Aureus. BIODEGRADATION OF ENDOSULFAN BY MIXED BACTERIA. CULTURE STRAINS OF PSEUDOMONAS AERUGINOSA AND. STAPHYLOCOCCUS AUREUS. Nwokem Nsidibeabasi Calvin1*, Nwokem Calvin Onyedika.2 , Gimba Casmir Emmanuel1 and Iwuala Beatrice Nkiruka1.

  19. Biodegradation of hydrocarbon compounds in Agbabu natural bitumen

    African Journals Online (AJOL)

    Infrared spectral changes and gravimetric analysis from the preliminary biodegradability study carried out on Agbabu Natural Bitumen showed the vulnerability of the bitumen to some bacteria: Pseudomonas putrefaciens, Pseudomonas nigrificans, Bacillus licheniformis, Pseudomonas fragi and Achromobacter aerogenes.

  20. Biodegradation of cycloalkane carboxylic acids in oil sand tailings

    Energy Technology Data Exchange (ETDEWEB)

    Herman, D.C.; Costerton, J.W. (Calgary Univ., Dept. of Biological Sciences, AB (Canada)); Fedorak, P.M. (Alberta Univ., Dept. of Microbiology, AB (Canada))

    1993-01-01

    The biodegradation of both an n-alkane and several carboxylated cycloalkanes was examined experimentally within tailings produced by the extraction of bitumen from the Athabasca oil sands. The carboxylated cycloalkanes examined were structurally similar to naphthenic acids that have been associated with the acute toxicity of oil sand tailings. The biodegradation potential of naphthenic acids was estimated by determining the biodegradation of both the carboxylated cycloalkanes and hexadecane in oil sand tailings. Carboxylated cycloalkanes were biodegraded within oil sands tailings, although compounds with methyl substitutions on the cycloalkane ring were more resistant to microbial degradation. Microbial activity against hexadecane and certain carboxylated cycloalkanes was found to be nitrogen and phosphorus limited. 21 refs., 3 refs., 1 tab.