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Sample records for adsorbent dosage initial

  1. Initial dosage regimens of gentamicin in patients with burns.

    PubMed

    Zaske, D E; Chin, T; Kohls, P R; Solem, L D; Strate, R G

    1991-01-01

    For 95 patients with burns the gentamicin dosage regimen necessary to achieve optimal serum concentrations was determined. Individual elimination rates and distribution volumes for gentamicin were determined and correlated with renal function parameters and age. In patients with burns who had normal serum creatinine levels (less than 1.5 mg/dl), gentamicin clearance and thus dosage regimens can be stratified by age. Gentamicin's clearance decreased inversely with age. Initial dosage guidelines were calculated for different age groups of patients with normal levels of serum creatinine. The guidelines were developed to assist the clinician in attaining therapeutic concentrations with initial doses of gentamicin. Therapeutic serum concentrations were reached in most patients with burns dosed by these guidelines. Serum gentamicin concentrations should always be monitored during therapy, and dosages should be adjusted to ensure optimal concentrations during the course of therapy.

  2. Design of initial dosage regimen using a programmable calculator.

    PubMed

    Ritschel, W A; Eldon, M A

    1985-07-01

    A programmable calculator procedure for the determination of dosage regimens to achieve desired steady state concentrations is described. The dosage regimen prediction is based on data from the literature on pharmacokinetic parameters of drugs and correction factors specific for the patient's condition, such as renal failure, geriatric patient and congestive heart failure. The program is designed to generate dosage regimens based on desired steady state trough level, desired steady state peak level, desired mean steady state level, or to fluctuate between desired steady state peak and trough levels. The program can be used for I.V. and extravascular route of administration. A detailed program description and user instructions are presented and illustrated by three examples.

  3. Congenital Hypothyroidism: Optimal Initial Dosage and Time of Initiation of Treatment: A Systematic Review

    PubMed Central

    Rahmani, Khaled; Yarahmadi, Shahin; Etemad, Koorosh; Koosha, Ahmad; Mehrabi, Yadollah; Aghang, Nasrin; Soori, Hamid

    2016-01-01

    Context Appropriate management of neonates, tested positive for congenital hypothyroidism (CH), in particular, the initial dosage of levothyroxine and the time of initiation of treatment is a critical issue. The aim of this study was to assess all current evidence available on the subject to ascertain the optimal initial dose and optimal initiation time of treatment for children with CH. Evidence Acquisition In this study, all published research related to the initiation treatment dose and the onset time of treatment in congenital hypothyroidism were reviewed. The searched electronic databases included Medline, Science direct, Scopus EMBASE, PsycINFO, Cochrane, BIOSIS and ISI Web of Knowledge. Additional searches included websites of relevant organizations, reference lists of included studies, and issues of major thyroid and pediatrics journals published within the past 35 years. Studies were included if they were written in English and investigated levothyroxine dose or timing of treatment or both, used for the treatment of children with congenital hypothyroidism. Results Two thousand three hundred and seventy-four articles (excluding duplicates) were retrieved from the primary search. After reviewing the titles, abstracts and full-texts of studies, eventually, 22 studies were found that met our inclusion criteria. Amongst these, 17 and 12 evaluated outcomes of different treatment doses and treatment timing, respectively. Overall, the majority of these studies emphasized the initial high dose of levothyroxine and early treatment of newborns with hypothyroidism. There were, however, some studies that disagreed with increasing levothyroxine dose at initiation of treatment. Conclusions Considering the results of this review, apparently there is no difference in opinion regarding the early initiation of treatment, whereas determining the optimal dose of levothyroxine for start of treatment in CH patients still remains a controversial issue, demonstrating the need for

  4. Reduced Dosage of Genes Encoding Ribosomal Protein S18 Suppresses a Mitochondrial Initiation Codon Mutation in Saccharomyces Cerevisiae

    PubMed Central

    Folley, L. S.; Fox, T. D.

    1994-01-01

    A yeast mitochondrial translation initiation codon mutation affecting the gene for cytochrome oxidase subunit III (COX3) was partially suppressed by a spontaneous nuclear mutation. The suppressor mutation also caused cold-sensitive fermentative growth on glucose medium. Suppression and cold sensitivity resulted from inactivation of the gene product of RPS18A, one of two unlinked genes that code the essential cytoplasmic small subunit ribosomal protein termed S18 in yeast. The two S18 genes differ only by 21 silent substitutions in their exons; both are interrupted by a single intron after the 15th codon. Yeast S18 is homologous to the human S11 (70% identical) and the Escherichia coli S17 (35% identical) ribosomal proteins. This highly conserved family of ribosomal proteins has been implicated in maintenance of translational accuracy and is essential for assembly of the small ribosomal subunit. Characterization of the original rps18a-1 missense mutant and rps18aΔ and rps18bΔ null mutants revealed that levels of suppression, cold sensitivity and paromomycin sensitivity all varied directly with a limitation of small ribosomal subunits. The rps18a-1 mutant was most affected, followed by rps18aΔ then rps18bΔ. Mitochondrial mutations that decreased COX3 expression without altering the initiation codon were not suppressed. This allele specificity implicates mitochondrial translation in the mechanism of suppression. We could not detect an epitope-tagged variant of S18 in mitochondria. Thus, it appears that suppression of the mitochondrial translation initiation defect is caused indirectly by reduced levels of cytoplasmic small ribosomal subunits, leading to changes in either cytoplasmic translational accuracy or the relative levels of cytoplasmic translation products. PMID:8070651

  5. Adsorption of methylene blue using modified adsorbents from drinking water treatment sludge.

    PubMed

    Nageeb Rashed, M; El-Daim El Taher, M A; Fadlalla, Somaya M M

    2016-10-01

    This study aims to explore the preparation and application of alum sludge (AS) and mud sludge (MS) from a drinking water treatment plant to remove methylene blue (MB) dye from aqueous solution. The sludge (MS and AS) was treated by chemical and physical activation to obtain new adsorbents. The adsorption experiments were carried out under different conditions of initial dye concentration (50-100 mg/L) adsorbent dosage (0.05-0.25 g), solution pH (3-9), temperature (20-60 °C) and contact time (20-90 min). Scanning electron microscopy (SEM) and X-ray diffraction instruments were used for characterization of the developed adsorbents. The results show that sludge activated by nitric acid (0.25 M HNO3) and pyrolysis at 700 °C were the best chemically and physically activated adsorbents. The optimum adsorption conditions for the adsorption of MB are 100 ppm initial dye concentration, 1 hour contact time, 250 °C solution temperature, pH 7 and 0.25 g adsorbent dosage. Application of the Langmuir and Freundlich Isotherm models showed that adsorbents fitted the Langmuir model well. SEM studies indicated the porous structural aspects of sludge suitable for removing MB dye.

  6. Adsorbent phosphates

    NASA Technical Reports Server (NTRS)

    Watanabe, S.

    1983-01-01

    An adsorbent which uses as its primary ingredient phosphoric acid salts of zirconium or titanium is presented. Production methods are discussed and several examples are detailed. Measurements of separating characteristics of some gases using the salts are given.

  7. Investigation on removal of malachite green using EM based compost as adsorbent.

    PubMed

    Bhagavathi Pushpa, T; Vijayaraghavan, J; Sardhar Basha, S J; Sekaran, V; Vijayaraghavan, K; Jegan, J

    2015-08-01

    The discarded materials from different sources can be utilized as effective materials in wastewater remediation. This proposed study was aimed mainly to investigate the possibility of Effective Microorganisms based compost (EMKC), which is derived from the kitchen solid waste, as a non-conventional low cost adsorbent for the removal of malachite green from aqueous solution. Batch experiments were carried out to evaluate the optimum operating parameters like pH (2-9), initial dye concentration (50-1000mg/L), adsorbent particle size (0.6-2.36mm) and adsorbent dosage (2-12g/L). EMKC recorded maximum uptake of 136.6mg/g of MG at pH 8, initial dye concentration 1000mg/L, adsorbent particle size 1.18mm and adsorbent dosage 4g/L. Two and three parameter adsorption models were employed to describe experimental biosorption isotherm data. The results revealed that the Sips model resulted in better fit than other models. The pseudo-first and -second order models were applied to describe kinetic data, of which the pseudo-second order described experimental data better with high correlation coefficient. This investigation suggested that EMKC could be an effective and low cost material for the removal of malachite green dye from aqueous solution.

  8. Dosage compensation of X-chromosome inactivation center-linked genes in porcine preimplantation embryos: Non-chromosome-wide initiation of X-chromosome inactivation in blastocysts.

    PubMed

    Hwang, Jae Yeon; Oh, Jong-Nam; Park, Chi-Hun; Lee, Dong-Kyung; Lee, Chang-Kyu

    2015-11-01

    X-chromosome inactivation (XCI) is an epigenetic mechanism that occurs in the eutherian embryo development to equalize the dosage of X-linked genes between males and females. This event is regulated by various factors, and the genes located in the X-chromosome inactivation center (XIC), which is known to be an evolutionary conserved region, are associated with XCI; however, a number of studies regarding this epigenetic event and genomic region are primarily performed in mouse models despite its species-specific features. Thus, in this study, the porcine XIC was identified, and we analyzed the expression of XIC-linked genes in porcine preimplantation embryos. Comparative sequence analysis revealed that the porcine XIC is synteny with that of human and the non-coding RNAs were less conserved compared with the protein coding genes in the XIC. Among the XIC-linked genes, the expression levels of CHIC1 and RLIM were decreased from morula to blastocyst development and their dosage was compensated between the male and female blastocysts. Additionally, the CpG sites of CHIC1 were approximately 50% methylated in parthenote blastocysts. Contrary to these genes, XIST and LOC102165544, an uncharacterized non-coding gene, showed dramatically increased expression levels after the morula stage and preferential female expression in blastocysts. Imprinted XIST expression was not observed, and their CpG sites were hypo-methylated in parthenogenic blastocysts. These results demonstrate that the porcine XIC consists of an evolutionary conserved structure with fewer sequences conserved non-coding RNAs. In addition, a few XIC-linked genes would likely achieve dosage compensation, but XCI would not be completed in porcine blastocysts.

  9. Methyl red removal from water by iron based metal-organic frameworks loaded onto iron oxide nanoparticle adsorbent

    NASA Astrophysics Data System (ADS)

    Dadfarnia, S.; Haji Shabani, A. M.; Moradi, S. E.; Emami, S.

    2015-03-01

    The objective followed by this research is the synthesis of iron based metal organic framework loaded on iron oxide nanoparticles (Fe3O4@MIL-100(Fe)) and the study of its capability for the removal of methyl red. Effective parameters in the selection of a new adsorbent, i.e. adsorption capacity, thermodynamics, and kinetics were investigated. All the studies were carried out in batch experiments. Removal of methyl red from aqueous solutions varied with the amount of adsorbent, methyl red contact time, initial concentration of dye, adsorbent dosage, and solution pH. The capability of the synthesized adsorbent in the removal of methyl red was compared with the metal organic framework (MIL-100(Fe)) and iron oxide nanoparticles. The results show that Fe3O4@MIL-100(Fe) nanocomposite exhibits an enhanced adsorption capacity.

  10. [Understanding dosage calculations].

    PubMed

    Benlahouès, Daniel

    2016-01-01

    The calculation of dosages in paediatrics is the concern of the whole medical and paramedical team. This activity must generate a minimum of risks in order to prevent care-related adverse events. In this context, the calculation of dosages is a practice which must be understood by everyone.

  11. Preparation and characterization of CTAB-HACC bentonite and its ability to adsorb phenol from aqueous solution.

    PubMed

    Huang, Ruihua; Zheng, Dongsheng; Yang, Bingchao; Wang, Bo; Zhang, Zengqiang

    2011-01-01

    A novel type of adsorbent was prepared by modifying bentonite with N-2-hydroxypropyl trimethyl ammonium chloride chitosan (HACC) with cetyl trimethylammonium bromide (CTAB). The adsorbent was named CTAB-HACC bentonite. Its characteristics were investigated using thermogravimetric, Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction. The adsorption of phenol onto CTAB-HACC bentonite was evaluated by changing various parameters, such as contact time, adsorbent dosage, initial pH of the solution, and temperature. The maximum adsorption was observed at pH 12. Adsorption of phenol on CTAB-HACC bentonite favored at lower temperature and established the equilibrium in 30 min. The adsorption efficiency reached 82.1%, and the adsorption capacity was 7.12 mg/g from the phenol solution with a concentration of 500 mg/L at pH 12.0 and 20 degrees C.

  12. A potential low cost adsorbent for the removal of cationic dyes from aqueous solutions

    NASA Astrophysics Data System (ADS)

    Uddin, Md. Tamez; Rahman, Md. Arifur; Rukanuzzaman, Md.; Islam, Md. Akhtarul

    2017-03-01

    This study was aimed at using mango leaf powder (MLP) as a potential adsorbent for the removal of methylene blue (MB) from aqueous solutions. Characterization of the adsorbent was carried out with scanning electron microscopy, Fourier transform infrared spectroscopy, and nitrogen adsorption-desorption analysis. The pH at the point of zero charge of the adsorbent was determined by titration method and was found a value to be 5.6 ± 0.2. Batch studies were performed to evaluate the influence of various experimental parameters like initial solution pH, contact time, initial concentration of dye and adsorbent dosage on the removal of MB. An adsorption-desorption study was carried out resulting the mechanism of adsorption was carried out by electrostatic force of attraction. The adsorption equilibrium time required for the adsorption of MB on MLP was almost 2 h and 85 ± 5% of the total amount of dye uptake was found to occur in the first rapid phase (30 min). The Langmuir and Freundlich isotherm models were used for modeling the adsorption equilibrium. The experimental equilibrium data could be well interpreted by Langmuir isotherm with maximum adsorption capacity of 156 mg/g. To state the sorption kinetics, the fits of pseudo-first-order and pseudo-second-order kinetic models were investigated. It was obtained that the adsorption process followed the pseudo-second-order rate kinetics. The above findings suggest that MLP can be effectively used for decontamination of dye containing wastewater.

  13. Microbicide dosage forms.

    PubMed

    Rohan, L C; Devlin, B; Yang, H

    2014-01-01

    Microbicides are topically applied, user controlled dosage forms that are being developed to prevent the transmission of HIV during coitus. Early candidates focused on coitally dependent dosage forms such as gels and creams. More recent development has focused on broadening the coitally dependent options through the introduction of films and fast dissolving tablets. Additionally, it has become important to have longer acting products to minimize the burden of user compliance and thus vaginal rings have been developed providing sustained delivery of antiretroviral drugs. This chapter discusses the history of microbicides along with a detailed description of coitally dependent products, gels, films, tablets diaphragms, as well as coitally independent dosage forms such as vaginal rings and the introduction of a new technology, electrospun fibers.

  14. From illite/smectite clay to mesoporous silicate adsorbent for efficient removal of chlortetracycline from water.

    PubMed

    Wang, Wenbo; Tian, Guangyan; Zong, Li; Zhou, Yanmin; Kang, Yuru; Wang, Qin; Wang, Aiqin

    2017-01-01

    A series of mesoporous silicate adsorbents with superior adsorption performance for hazardous chlortetracycline (CTC) were sucessfully prepared via a facile one-pot hydrothermal reaction using low-cost illite/smectite (IS) clay, sodium silicate and magnesium sulfate as the starting materials. In this process, IS clay was "teared up" and then "rebuilt" as new porous silicate adsorbent with high specific surface area of 363.52m(2)/g (about 8.7 folds higher than that of IS clay) and very negative Zeta potential (-34.5mV). The inert SiOSi (Mg, Al) bonds in crystal framework of IS were broken to form Si(Al) O(-) groups with good adsorption activity, which greatly increased the adsorption sites served for holding much CTC molecules. Systematic evaluation on adsorption properties reveals the optimal silicate adsorbent can adsorb 408.81mg/g of CTC (only 159.7mg/g for raw IS clay) and remove 99.3% (only 46.5% for raw IS clay) of CTC from 100mg/L initial solution (pH3.51; adsorption temperature 30°C; adsorbent dosage, 3g/L). The adsorption behaviors of CTC onto the adsorbent follows the Langmuir isotherm model, Temkin equation and pseudo second-order kinetic model. The mesopore adsorption, electrostatic attraction and chemical association mainly contribute to the enhanced adsorption properties. As a whole, the high-efficient silicate adsorbent could be candidates to remove CTC from the wastewater with high amounts of CTC.

  15. Removal of methylene blue from wastewater using fly ash as an adsorbent by hydrocyclone.

    PubMed

    Rastogi, K; Sahu, J N; Meikap, B C; Biswas, M N

    2008-10-30

    The excessive release of color into the environment is a major concern worldwide. Adsorption process is among the most effective techniques for color removal from wastewater and fly ash has been widely used as an adsorbent. Therefore, this study was carried out to understand the adsorption behavior of methylene blue from aqueous systems onto fly ash using the continuous mode. Continuous mode sorption experiments were carried out to remove methylene blue from its aqueous solutions in hydrocyclone equipment. The experiments were performed at constant temperature and dimensions of hydrocyclone with variation of flows through the equipment, concentrations of methylene blue solutions and fly ash concentration, respectively. A maximum removal of 58.24% was observed at adsorbent dosage of 900 mg/l at pH 6.75 for an initial methylene blue concentration of 65 mg/l.

  16. Evolution of dosage compensation.

    PubMed

    Steinemann, M; Steinemann, S; Turner, B M

    1996-04-01

    In polytene chromosome squashes from the fruit fly Drosophila melanogaster, the single, dosage-compensated X chromosome in males can be distinguished from the autosomes by the presence of an isoform of histone H4 acetylated at lysine 16, H4.Ac16. We have used H4.Ac16 as a marker to examine the evolving relationship between dosage compensation and sex chromosome composition in species of Drosophila with one (D. melanogaster), two (D. pseudoobscura) or three (D. miranda) identifiable X chromosome arms. In each case, we find that H4.Ac16 is distributed as discrete, closely spaced bands along the entire length of each X chromosome, the only exception being the X2 chromosome of D. miranda in which a terminal region constituting about 10% of the chromosome by length is not labelled with anti-H4.Ac16 antibodies. We conclude that, with this exception, dosage compensation extends along the X chromosomes of all three species. As D. pseudoobscura and D. miranda diverged only about 2 Mya, the spread of dosage-compensated loci along X2 has been rapid, suggesting that regional changes rather than piecemeal, gene-by-gene, changes may have been involved.

  17. Removal of heavy metal ions from aqueous solution using red loess as an adsorbent.

    PubMed

    Xing, Shengtao; Zhao, Meiqing; Ma, Zichuan

    2011-01-01

    The adsorption behaviors of heavy metals onto novel low-cost adsorbent, red loess, were investigated. Red loess was characterized by X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectra. The results indicated that red loess mainly consisted of silicate, ferric and aluminum oxides. Solution pH, adsorbent dosage, initial metal concentration, contact time and temperature significantly influenced the efficiency of heavy metals removal. The adsorption reached equilibrium at 4 hr, and the experimental equilibrium data were fitted to Langmuir monolayer adsorption model. The adsorption of Cu(II) and Zn(II) onto red loess was endothermic, while the adsorption of Pb(II) was exothermic. The maximum adsorption capacities of red loess for Pb(II), Cu(II) and Zn(II) were estimated to be 113.6, 34.2 and 17.5 mg/g, respectively at 25 degrees C and pH 6. The maximum removal efficiencies were 100% for Pb(II) at pH 7, 100% for Cu(II) at pH 8, and 80% for Zn(II) at pH 8. The used adsorbents were readily regenerated using dilute HCl solution, indicating that red loess has a high reusability. All the above results demonstrated that red loess could be used as a possible alternative low-cost adsorbent for the removal of heavy metals from aqueous solution.

  18. Waste metal hydroxide sludge as adsorbent for a reactive dye.

    PubMed

    Santos, Sílvia C R; Vílar, Vítor J P; Boaventura, Rui A R

    2008-05-30

    An industrial waste sludge mainly composed by metal hydroxides was used as a low-cost adsorbent for removing a reactive textile dye (Remazol Brilliant Blue) in solution. Characterization of this waste material included chemical composition, pH(ZPC) determination, particle size distribution, physical textural properties and metals mobility under different pH conditions. Dye adsorption equilibrium isotherms were determined at 25 and 35 degrees C and pH of 4, 7 and 10 revealing reasonably fits to Langmuir and Freundlich models. At 25 degrees C and pH 7, Langmuir fit indicates a maximum adsorption capacity of 91.0mg/g. An adsorptive ion-exchange mechanism was identified from desorption studies. Batch kinetic experiments were also conducted at different initial dye concentration, temperature, adsorbent dosage and pH. A pseudo-second-order model showed good agreement with experimental data. LDF approximation model was used to estimate homogeneous solid diffusion coefficients and the effective pore diffusivities. Additionally, a simulated real effluent containing the selected dye, salts and dyeing auxiliary chemicals, was also used in equilibrium and kinetic experiments and the adsorption performance was compared with aqueous dye solutions.

  19. Dosage Compensation in Mammals

    PubMed Central

    Brockdorff, Neil; Turner, Bryan M.

    2015-01-01

    Many organisms show major chromosomal differences between sexes. In mammals, females have two copies of a large, gene-rich chromosome, the X, whereas males have one X and a small, gene-poor Y. The imbalance in expression of several hundred genes is lethal if not dealt with by dosage compensation. The male–female difference is addressed by silencing of genes on one female X early in development. However, both males and females now have only one active X chromosome. This is compensated by twofold up-regulation of genes on the active X. This complex system continues to provide important insights into mechanisms of epigenetic regulation. PMID:25731764

  20. Modeling adsorption: Investigating adsorbate and adsorbent properties

    NASA Astrophysics Data System (ADS)

    Webster, Charles Edwin

    1999-12-01

    Surface catalyzed reactions play a major role in current chemical production technology. Currently, 90% of all chemicals are produced by heterogeneously catalyzed reactions. Most of these catalyzed reactions involve adsorption, concentrating the substrate(s) (the adsorbate) on the surface of the solid (the adsorbent). Pore volumes, accessible surface areas, and the thermodynamics of adsorption are essential in the understanding of solid surface characteristics fundamental to catalyst and adsorbent screening and selection. Molecular properties such as molecular volumes and projected molecular areas are needed in order to convert moles adsorbed to surface volumes and areas. Generally, these molecular properties have been estimated from bulk properties, but many assumptions are required. As a result, different literature values are employed for these essential molecular properties. Calculated molar volumes and excluded molecular areas are determined and tabulated for a variety of molecules. Molecular dimensions of molecules are important in the understanding of molecular exclusion as well as size and shape selectivity, diffusion, and adsorbent selection. Molecular dimensions can also be used in the determination of the effective catalytic pore size of a catalyst. Adsorption isotherms, on zeolites, (crystalline mineral oxides) and amorphous solids, can be analyzed with the Multiple Equilibrium Analysis (MEA) description of adsorption. The MEA produces equilibrium constants (Ki), capacities (ni), and thermodynamic parameters (enthalpies, ΔHi, and entropies, ΔSi) of adsorption for each process. Pore volumes and accessible surface areas are calculated from the process capacities. Adsorption isotherms can also be predicted for existing and new adsorbate-adsorbent systems with the MEA. The results show that MEA has the potential of becoming a standard characterization method for microporous solids that will lead to an increased understanding of their behavior in gas

  1. Enteric coating of mycophenolate reduces dosage adjustments.

    PubMed

    Brister, K; Yau, C L; Slakey, D

    2009-06-01

    Mycophenolate mofetil (MMF) and enteric-coated mycophenolate sodium (EC-MPS) are bioequivalent. However, the effectiveness of MMF may be limited by gastrointestinal (GI) side effects. This study assessed the relationship between the number of medication dosage adjustments and posttransplantation side effects. In a review of 109 kidney transplant patients, 65 initially received MMF and 44 initially received EC-MPS. The incidences of patient-reported GI complications were significantly different: MMF 45.5% vs EC-MPS 35.3% (P = .0194). The proportions of patients requiring dosage adjustment due to GI complications were MMF 5.9% and EC-MPS 2.3% (P < .0001). Patients receiving MMF were more likely to experience GI complications resulting in dosage adjustment (odds ratio = 9.9; P = .0306). The incidences of acute rejection, cytomegalovirus (CMV), and leukopenia resulting in dosage adjustment were not significantly different. Patients receiving MMF required more immunosuppressive medication adjustments, which may complicate care and decrease overall compliance.

  2. Effective removal of Congo red dye from aqueous solution using modified xanthan gum/silica hybrid nanocomposite as adsorbent.

    PubMed

    Ghorai, Soumitra; Sarkar, Amit Kumar; Panda, A B; Pal, Sagar

    2013-09-01

    The aim of this work is to study the feasibility of XG-g-PAM/SiO2 nanocomposite towards its potential application as high performance adsorbent for removal of Congo red (CR) dye from aqueous solution. The surface area, average pore size and total pore volume of the developed nanocomposite has been determined. The efficiency of CR dye adsorption depends on various factors like pH, temperature of the solution, equilibrium time of adsorption, agitation speed, initial concentration of dye and adsorbent dosage. It has been observed that the nanocomposite is having excellent CR dye adsorption capacity (Q0=209.205 mg g(-1)), which is considerably high. The dye adsorption process is controlled by pseudo-second order and intraparticle diffusion kinetic models. The adsorption equilibrium data correlates well with Langmuir isotherm. Desorption study indicates the efficient regeneration ability of the dye loaded nanocomposite.

  3. Using poly([1-vinyl-3-hexylimidazolium] [bis(trifluoromethylsulfonyl)imide]) to adsorb bio-ethanol from a Chamaecyparis obtuse leaves fermentation broth.

    PubMed

    Tang, Baokun; Bi, Wentao; Row, Kyung Ho

    2013-06-01

    Poly([1-vinyl-3-hexylimidazolium] [bis(trifluoromethylsulfonyl)imide]) (poly([VHIM][Tf2N])) was assessed for its ability to adsorb bio-ethanol from Chamaecyparis obtuse leaves fermentation broths. Poly([VHIM][Tf2N]) was prepared by poly([VHIM][Br]) ion exchange with Li(Tf2N). Poly([VHIM][Br]) was obtained using a thermal-initiated polymerization method. The factors affecting the adsorption capacity of poly([VHIM][Tf2N]), such as the initial concentration of bio-ethanol in the fermentation broth, adsorption temperature and dosage of the adsorbent, as well as the adsorption kinetics and equilibrium of poly([VHIM][Tf2N]) were investigated. The Langmuir, Freundlich and Temkin isotherms used to describe the adsorption of bio-ethanol on the adsorbent showed good correlation coefficients of 0.97, 0.96 and 0.98, respectively. A comparison of the separation factors for ethanol/water, ethanol/glucose and ethanol/xylose revealed poly([VHIM][Tf2N]) to have preferential selectivity for bio-ethanol. Compared to activated carbon, poly([VHIM][Tf2N]) exhibited higher adsorption capacity for bio-ethanol under the same adsorption conditions. The adsorbent could be used for 5 cycles with good efficiency, highlighting its reusability as an adsorbent.

  4. Controlled release liquid dosage formulation

    DOEpatents

    Benton, Ben F.; Gardner, David L.

    1989-01-01

    A liquid dual coated dosage formulation sustained release pharmaceutic having substantial shelf life prior to ingestion is disclosed. A dual coating is applied over controlled release cores to form dosage forms and the coatings comprise fats melting at less than approximately 101.degree. F. overcoated with cellulose acetate phthalate or zein. The dual coated dosage forms are dispersed in a sugar based acidic liquid carrier such as high fructose corn syrup and display a shelf life of up to approximately at least 45 days while still retaining their release profiles following ingestion. Cellulose acetate phthalate coated dosage form cores can in addition be dispersed in aqueous liquids of pH <5.

  5. Synthesis of nickel sulfide nanoparticles loaded on activated carbon as a novel adsorbent for the competitive removal of Methylene blue and Safranin-O.

    PubMed

    Ghaedi, M; Pakniat, M; Mahmoudi, Z; Hajati, S; Sahraei, R; Daneshfar, A

    2014-04-05

    Nickel sulfide nanoparticle-loaded activated carbon (NiS-NP-AC) were synthesized as a novel adsorbent for simultaneous and rapid adsorption of Methylene blue (MB) and Safranin-O (SO), as most together compounds in wastewater. NiS-NP-AC was characterized using different techniques such as UV-visible, Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Brunauer-Emmett-Teller (BET). The surface area of the adsorbent was found to be very high (1018m(2)/g according BET). By using central composite design (CCD), the effects of variables such as pH, adsorbent dosage, MB concentration, SO concentration and contact time on binary dyes removal were examined and optimized values were found to be 8.1, 0.022g, 17.8mg/L, and 5mg/L and 5.46min, respectively. The very short time required for the dyes removal makes this novel adsorbent as a promising tool for wastewater treatment applications. Different models were applied to analyze experimental isotherm data. Modified-extended Langmuir model showed good fit to equilibrium data with maximum adsorption capacity at 0.022g of adsorbent. An empirical extension of competitive modified-extended Langmuir model was proposed to predict the simultaneous adsorption behavior of MB and SO. Kinetic models were applied to fit the experimental data at various adsorbent dosages and initial dyes concentrations. It was seen that pseudo-second-order equation is suitable to fit the experimental data. Individual removalof each dye was also studied.

  6. Magnetic Fe3O4@C nanoparticles as adsorbents for removal of amoxicillin from aqueous solution.

    PubMed

    Kakavandi, Babak; Esrafili, Ali; Mohseni-Bandpi, Anoushiravan; Jonidi Jafari, Ahmad; Rezaei Kalantary, Roshanak

    2014-01-01

    In the present study, powder activated carbon (PAC) combined with Fe(3)O(4) magnetite nanoparticles (MNPs) were used for the preparation of magnetic composites (MNPs-PAC), which was used as an adsorbent for amoxicillin (AMX) removal. The properties of magnetic activated carbon were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Brunaeur, Emmett and Teller and vibrating sample magnetometer. The operational factors affecting adsorption such as pH, contact time, adsorbent dosage, initial AMX concentration and temperature were studied in detail. The high surface area and saturation magnetization for the synthesized adsorbent were found to be 671.2 m(2)/g and 6.94 emu/g, respectively. The equilibrium time of the adsorption process was 90 min. Studies of adsorption equilibrium and kinetic models revealed that the adsorption of AMX onto MNPs-PAC followed Freundlich and Langmuir isotherms and pseudo-second-order kinetic models. The calculated values of the thermodynamic parameters, such as ΔG°, ΔH° and ΔS° demonstrated that the AMX adsorption was endothermic and spontaneous in nature. It could be concluded that MNPs-PAC have a great potential for antibiotic removal from aquatic media.

  7. Molecular Adsorber Coating

    NASA Technical Reports Server (NTRS)

    Straka, Sharon; Peters, Wanda; Hasegawa, Mark; Hedgeland, Randy; Petro, John; Novo-Gradac, Kevin; Wong, Alfred; Triolo, Jack; Miller, Cory

    2011-01-01

    A document discusses a zeolite-based sprayable molecular adsorber coating that has been developed to alleviate the size and weight issues of current ceramic puck-based technology, while providing a configuration that more projects can use to protect against degradation from outgassed materials within a spacecraft, particularly contamination-sensitive instruments. This coating system demonstrates five times the adsorption capacity of previously developed adsorber coating slurries. The molecular adsorber formulation was developed and refined, and a procedure for spray application was developed. Samples were spray-coated and tested for capacity, thermal optical/radiative properties, coating adhesion, and thermal cycling. Work performed during this study indicates that the molecular adsorber formulation can be applied to aluminum, stainless steel, or other metal substrates that can accept silicate-based coatings. The coating can also function as a thermal- control coating. This adsorber will dramatically reduce the mass and volume restrictions, and is less expensive than the currently used molecular adsorber puck design.

  8. Magnetic-epichlorohydrin crosslinked chitosan schiff's base (m-ECCSB) as a novel adsorbent for the removal of Cu(II) ions from aqueous environment.

    PubMed

    Gutha, Yuvaraja; Zhang, Yaping; Zhang, Weijiang; Jiao, Xu

    2017-04-01

    Metal ions cause a serious public health problem. It is a great challenge to find an effective and efficient adsorbent to remove heavy metals from wastewater. Chitosan-based adsorbents are potential and effective for heavy metal ion removal. Hence a novel m-ECCSB was synthesized, characterized and utilized as an adsorbent for the removal of Cu(II) ions from aqueous solution. Various factors affecting the uptake behavior such as pH, adsorbent dosage, contact time, initial concentration of Cu(II) and temperature effect were investigated. Maximum adsorption capability (123.10mg/g) was obtained at pH=6, adsorbent dose of=250mg, rotational speed=200rpm, contact time=60min, and temperature of 323K. The result of the kinetic study shows that the adsorption of Cu(II) could be described by the pseudo-second-order equation. Equilibrium data were analysed with the Langmuir, Freundlich and Dubinin-Radushkevich isotherms and Langmuir model was found to provide the best fit of the experimental data. The thermodynamic parameters showed that the adsorption of Cu(II) onto m-ECCSB was spontaneous (ΔG°=-8.990, -10.00 and -10.593kJ/mol), endothermic (ΔH°=15.674, 15.478 and 15.699kJ/mol) and ΔS° (0.0814J/molK) suggests an increased randomness at the solid/solution interface under the studied conditions.

  9. Treatment of industrial wastewater containing Congo Red and Naphthol Green B using low-cost adsorbent.

    PubMed

    Attallah, M F; Ahmed, I M; Hamed, Mostafa M

    2013-02-01

    The present work investigates the potential use of metal hydroxides sludge (MHS) generated from hot dipping galvanizing plant for adsorption of Congo Red and Naphthol Green B dyes from aqueous solutions. Characterization of MHS included infrared and X-ray fluorescence analysis. The effect of shaking time, initial dye concentration, temperature, adsorbent dosage and pH has been investigated. The results of adsorption experiments indicate that the maximum capacity of Congo Red and Naphthol Green B dyes at equilibrium (q(e)) and percentage of removal at pH 6 are 40 mg/g, 93 %, and 10 mg/g, 52 %, respectively. Some kinetic models were used to illustrate the adsorption process of Congo Red and Naphthol Green B dyes using MHS waste. Thermodynamic parameters such as (ΔG, ΔS, and ΔH) were also determined.

  10. Clarified sludge (basic oxygen furnace sludge)--an adsorbent for removal of Pb(II) from aqueous solutions--kinetics, thermodynamics and desorption studies.

    PubMed

    Naiya, Tarun Kumar; Bhattacharya, Ashim Kumar; Das, Sudip Kumar

    2009-10-15

    The basic oxygen furnace waste generated in steel plant has been used as a low cost adsorbent for the removal of Pb(II) from aqueous solution. The effect of pH, adsorbent dosage, initial metal ion concentration, contact time and temperature on adsorption process was studied in batch experiments. Results of the equilibrium experiments showed that the solution pH was the key factor affecting the adsorption characteristics. Optimum pH for the adsorption was found to be 5 with corresponding adsorbent dosage level of 5 g/L. The equilibrium was achieved within 1h of contact time. Kinetics data were best described by pseudo second order model. The effective particle diffusion coefficient of Pb(II) is the order of 10(-10)m(2)/s. The maximum uptake was 92.5mg/g. The adsorption data can be well fitted by Freundlich isotherm. The result of the equilibrium studies showed that the solution pH was the key factor affecting the adsorption. External mass transfer analysis was also carried out for the adsorption process. The thermodynamic studies indicated that the adsorption is spontaneous and endothermic. The sorption energy (10.1745 kJ/mol) calculated from Dubinin-Radushkevich isotherm indicated that the adsorption process is chemical in nature. Desorption studies were carried out using dilute mineral acids to elucidate the mechanism of adsorption. Application studies were carried out considering the economic viewpoint of wastewater treatment plant operations.

  11. Regenerative adsorbent heat pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor)

    1991-01-01

    A regenerative adsorbent heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system and at least a portion of the heat of adsorption. A series of at least four compressors containing an adsorbent is provided. A large amount of heat is transferred from compressor to compressor so that heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

  12. Applications and limits of theoretical adsorption models for predicting the adsorption properties of adsorbents.

    PubMed

    Park, Hyun Ju; Nguyen, Duc Canh; Na, Choon-Ki; Kim, Chung-il

    2015-01-01

    The objective of this study is to evaluate the applicability of adsorption models for predicting the properties of adsorbents. The kinetics of the adsorption of NO3- ions on a PP-g-AA-Am non-woven fabric have been investigated under equilibrium conditions in both batch and fixed bed column processes. The adsorption equilibrium experiments in the batch process were carried out under different adsorbate concentration and adsorbent dosage conditions and the results were analyzed using adsorption isotherm models, energy models, and kinetic models. The results of the analysis indicate that the adsorption occurring at a fixed adsorbate concentration with a varying adsorbent dosage occur more easily compared to those under a fixed adsorbent dosage with a varying adsorbate concentration. In the second part of the study, the experimental data obtained using fixed bed columns were fit to Bed Depth Service Time, Bohart-Adams, Clark, and Wolborska models, to predict the breakthrough curves and determine the column kinetic parameters. The adsorption properties of the NO3- ions on the PP-g-AA-Am non-woven fabric were differently described by different models for both the batch and fixed bed column process. Therefore, it appears reasonable to assume that the adsorption properties were dominated by multiple mechanisms, depending on the experimental conditions.

  13. Adsorbent and adsorbent bed for materials capture and separation processes

    DOEpatents

    Liu, Wei

    2011-01-25

    A method device and material for performing adsorption wherein a fluid mixture is passed through a channel in a structured adsorbent bed having a solid adsorbent comprised of adsorbent particles having a general diameter less than 100 um, loaded in a porous support matrix defining at least one straight flow channel. The adsorbent bed is configured to allow passage of a fluid through said channel and diffusion of a target material into said adsorbent under a pressure gradient driving force. The targeted molecular species in the fluid mixture diffuses across the porous support retaining layer, contacts the adsorbent, and adsorbs on the adsorbent, while the remaining species in the fluid mixture flows out of the channel.

  14. Nuclear organization and dosage compensation.

    PubMed

    Chow, Jennifer C; Heard, Edith

    2010-11-01

    Dosage compensation is a strategy to deal with the imbalance of sex chromosomal gene products relative to autosomes and also between the sexes. The mechanisms that ensure dosage compensation for X-chromosome activity have been extensively studied in mammals, worms, and flies. Although each entails very different mechanisms to equalize the dose of X-linked genes between the sexes, they all involve the co-ordinate regulation of hundreds of genes specifically on the sex chromosomes and not the autosomes. In addition to chromatin modifications and changes in higher order chromatin structure, nuclear organization is emerging as an important component of these chromosome-wide processes and in the specific targeting of dosage compensation complexes to the sex chromosomes. Preferential localization within the nucleus and 3D organization are thought to contribute to the differential treatment of two identical homologs within the same nucleus, as well as to the chromosome-wide spread and stable maintenance of heterochromatin.

  15. Time Resolved Studies Of Adsorbed Species

    NASA Astrophysics Data System (ADS)

    Howard, J.; Nicol, J. M.

    1985-12-01

    A time-resolved Fourier transform IR study of ethyne adsorbed on ZnNaA zeolite yields results very different from those reported for related systems. Initially two species (A and B) are formed by the interaction of C2H2 with the cations. Whereas species A (π-bonded C2H2) was found to be removed immediately on evacuation, species B (probably Zn-acetylide) was not fully removed after 60 mins evacuation. In the presence of the gas phase, bands due to Species A decreased slowly in intensity as new bands due to adsorbed ethanal were observed.

  16. Removal effects and mechanisms of Microcystic aeruginosa by Chitosan-modified Adsorbent

    NASA Astrophysics Data System (ADS)

    Yang, Xi; Wu, Cuirong; He, Yan; Zhang, Bingru; Li, Fengting

    2010-11-01

    The health of humans and other organisms is threatened by increasingly serious water contamination by algae in all the country's major lakes such as Taihu Lake. This experiment was conducted to investigate the removal effects and mechanism of Microcystic aeruginosa by Chitosan-modified adsorbent, with comparison of polyaluminium chloride (PAC) and poly ferric sulfate (PFS). Microcystic aeruginosa grown in the laboratory was used for this experiment. The results showed that the algae-removal efficiency of Chitosan-modified adsorbent presents a good performance. When the dosage of the adsorbent reached 20 ppm, the turbidity and the chlorophyll a of treated water dropped by 90% and 86%, respectively. Compared to conventional coagulation, the dosage was reduced. The adhesive bridge effect of Chitosan and adsorption of modified adsorbent provided an important complement to subsequent dehydrating treatment for algae.

  17. Carboxylated carbon nanotubes as an efficient and cost-effective adsorbent for sustainable removal of insecticide fenvalerate from contaminated solutions

    NASA Astrophysics Data System (ADS)

    Naeimi, Atena; Saeidi, Mahboubeh; Baroumand, Naser

    2016-10-01

    In this study, carboxylic multiwall carbon nanotubes (CMNTs) were used as an adsorbent for removing fenvalerate as a toxic insecticide from solution through batch experiments. The influence of four independent parameters of HCl, initial fenvalerate concentration, CMNTs dosage, and contact time on the fenvalerate adsorption process was investigated. Raman spectroscopy and thermogravimetric analysis confirmed that the adsorption and maximum adsorption capacity (40.0 mg g-1) showed high adsorption potential of the proposed sorbent. The kinetic, isothermic, and thermodynamic of fenvalerate adsorptionon CMNTs were evaluated to better understand this environmental friendly adsorption strategy. A pseudo-first-order kinetic described very well the experimental data of the adsorption kinetics. The experimental data found to be properly fitted to Freundlich model, which indicates that the sorption takes place on a heterogeneous material. The thermodynamic results showed the negative value of the standard free energy (Δ G0) and standard enthalpy change (Δ H0) showing an exothermic and spontaneous system. Repeated availability of adsorbent investigated and SEM and HRTEM of reused adsorbent showed stability and non-aggregatable attributes of CMNTs.

  18. Sorption studies of Cr(VI) from aqueous solution using bio-char as an adsorbent.

    PubMed

    Hyder, A H M G; Begum, Shamim A; Egiebor, Nosa O

    2014-01-01

    The characteristics of sorption of hexavalent chromium (Cr(VI)) onto bio-char derived from wood chips (spruce, pine, and fir) were evaluated as a function of pH, initial Cr(VI) concentration and bio-char dosage using synthetic wastewater in batch tests. The initial Cr(VI) concentrations were varied between 10 and 500 mg/L to investigate equilibrium, kinetics, and isotherms of the sorption process. About 100% of Cr(VI) was removed at pH 2 with initial Cr(VI) concentration of 10 mg/L using 4 g of bio-char after 5 hours of sorption reaction. The maximum sorption capacity of the bio-char was 1.717 mg/g for an initial Cr(VI) concentration of 500 mg/L after 5 hours. The sorption kinetics of total Cr onto bio-char followed the second-order kinetic model. The Langmuir isotherm model provided the best fit for total Cr sorption onto bio-char. The bio-char used is a co-product of a down draft gasifier that uses the derived syngas to produce electricity. Bio-char as a low cost adsorbent demonstrated promising results for removal of Cr(VI) from aqueous solution. The findings of this study would be useful in designing a filtration unit with bio-char in a full-scale water and wastewater treatment plant for the Cr(VI) removal from contaminated waters.

  19. Fluoxetine and sertraline dosages in major depression.

    PubMed

    Cantrell, R; Gillespie, W; Altshuler, L

    1999-01-01

    In a retrospective study, we sought to determine medication dosages usually prescribed to obtain euthymia in 59 outpatients with a diagnosis of major depression treated with fluoxetine or sertraline. Charts of veterans admitted to the outpatient mental health clinic at the West Los Angeles Veterans Hospital with a diagnosis of major depression and treated with either fluoxetine or sertraline were reviewed. Progress notes were analyzed for a 6-month time period after the initiation of the medication treatment, and improvement was rated by a physician blind to the drug used for treatment. No significant differences were found in overall response rates between the fluoxetine (81% responders) and sertraline (76% responders) groups. Eighty-one percent of the fluoxetine responders compared to 32% of sertraline responders were at the manufacturer's recommended starting dose (MRSD) at the time of clinical response. One-third of patients receiving sertraline were started on or rapidly titrated to more than 50 mg/day. When only those patients receiving an adequate trial of sertraline at 50 mg were considered, 47% required a dose increase to achieve a remission. These data suggest that 50 mg of sertraline may be inadequate for some patients to achieve a resolution of symptoms of major depression and that many clinicians currently prescribe in a manner suggesting that they believe the MRSD is a suboptimal dosage.

  20. Radiopharmaceutical dosage selection for pediatric nuclear medicine

    SciTech Connect

    Shore, R.M.; Hendee, W.R.

    1986-02-01

    To identify the most rational method for adjusting adult radiopharmaceutical dosages for children, four methods of dosage computation were examined from the perspectives of diagnostic adequacy and radiation absorbed dose. For static imaging, information density is the most important factor in study quality, and adjustment of dosage by body weight (Wt) for thick organs, and body surface area (BSA) for thin organs is recommended. Compared with adults, small children receive less radiation exposure if radiopharmaceutical dosages are adjusted by Wt, and slightly greater exposure if dosages are adjusted by BSA. For dynamic imaging studies, dosage requirements are governed by the spatial resolution needed for region of interest assignment, and the statistical reliability of the time-activity data. For dynamic renal imaging, renograms of similar quality are obtained if dosages are adjusted by height (Ht). Dynamic cardiac studies might appear to require dosages even larger than those adjusted by Ht which would result in higher radiation absorbed doses to pediatric patients. However, smaller dosages can be used in children by prolonging the imaging time and accepting lower temporal resolution. Dosage requirements for dynamic studies depend on which physiologic characteristics are measured from the time-activity data. Since the measurements of some characteristics demand higher count rates than others, dosage requirements ultimately depend on which measurements are clinically necessary. Close attention to the factors that determine these requirements may yield significant reduction in dosages, and thus in radiation exposure, for patients of all ages.

  1. Co-modified MCM-41 as an effective adsorbent for levofloxacin removal from aqueous solution: optimization of process parameters, isotherm, and thermodynamic studies.

    PubMed

    Jin, Ting; Yuan, Wenhua; Xue, Yujie; Wei, Hong; Zhang, Chaoying; Li, Kebin

    2016-12-21

    Antibiotics are emerging contaminants due to their potential risks to human health and ecosystems. Poor biodegradability makes it necessary to develop effective physical-chemical methods to eliminate these contaminants from water. The cobalt-modified MCM-41 was prepared by a one-pot hydrothermal method and characterized by SAXRD, N2 adsorption-desorption, SEM, UV-Vis DR, and FTIR spectroscopy. The results revealed that the prepared 3% Co-MCM-41 possessed mesoporous structure with BET surface areas at around 898.5 m(2)g(-1). The adsorption performance of 3% Co-MCM-41 toward levofloxacin (LVF) was investigated by batch experiments. The adsorption of LVF on 3% Co-MCM-41 was very fast and reached equilibrium within 2 h. The adsorption kinetics followed the pseudo-second-order kinetic model with the second-order rate constants in the range of 0.00198-0.00391 g mg(-1) min(-1). The adsorption isotherms could be well represented by the Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm equations. Nevertheless, D-R isotherm provided the best fit based on the coefficient of determination and average relative error values. The mean free energy of adsorption (E) calculated from D-R model was about 11 kJ mol(-1), indicating that the adsorption was mainly governed by a chemisorption process. Moreover, the adsorption capacity was investigated as a function of pH, adsorbent dosage, LVF concentration, and temperature with help of respond surface methodology (RSM). A quadratic model was established, and an optimal condition was obtained as follows: pH 8.5, adsorbent dosage of 1 g L(-1), initial LVF concentration of 119.8 mg L(-1), and temperature of 31.6 °C. Under the optimal condition, the adsorption capacity of 3% Co-MCM-41 to LVF could reach about 108.1 mg g(-1). The solution pH, adsorbent dosage, LVF concentration, and a combination of adsorbent dose and LVF concentration were significant factors affecting the adsorption process. The adsorption

  2. Removal of hazardous azopyrazole dye from an aqueous solution using rice straw as a waste adsorbent: Kinetic, equilibrium and thermodynamic studies

    NASA Astrophysics Data System (ADS)

    El-Bindary, Ashraf A.; El-Sonbati, Adel Z.; Al-Sarawy, Ahmad A.; Mohamed, Khaled S.; Farid, Mansour A.

    2015-02-01

    In this research, activated carbonmade from rice straw (ACRS) was synthesized simply by a low cost and nontoxic procedure and used for the adsorption of hazardous azopyrazole dye. The effect of different variables in the batch method as a function of solution pH, contact time, concentration of adsorbate, adsorbent dosage and temperature were investigated and optimal experimental conditions were ascertaine. Surface modification of ACRS using scanning electron microscopy (SEM) was obtained. More than 75% removal efficiency was obtained within 75 min at adsorbent dose of 0.5 g for initial dye concentration of 30-100 mg L-1 at pH 3. The experimental equilibrium data were tested by the isotherm models namely, Langmuir and Freundlich adsorption and the isotherm constants were determined. The kinetic data obtained with different initial concentration and temperature were analyzed using a pseudo-first-order and pseudo-second-order equations. The activation energy of adsorption was also evaluated and found to be +13.25 kJ mol-1 indicating that the adsorption is physisorption. The thermodynamics of the adsorption indicated spontaneous and exothermic nature of the process. The results indicate that ACRS could be employed as low-cost material for the removal of acid dyes from aqueous solution.

  3. Removal of nitrate and phosphate using chitosan/Al2O3/Fe3O4 composite nanofibrous adsorbent: Comparison with chitosan/Al2O3/Fe3O4 beads.

    PubMed

    Bozorgpour, Farahnaz; Ramandi, Hossein Fasih; Jafari, Pooya; Samadi, Saman; Yazd, Shabnam Sharif; Aliabadi, Majid

    2016-12-01

    In the present study the chitosan/Al2O3/Fe3O4 composite nanofibrous adsorbent was prepared by electrospinning process and its application for the removal of nitrate and phosphate were compared with chitosan/Al2O3/Fe3O4 composite bead adsorbent. The influence of Al2O3/Fe3O4 composite content, pH, contact time, nitrate and phosphate initial concentrations and temperature on the nitrate and phosphate sorption using synthesized bead and nanofibrous adsorbents was investigated in a single system. The reusability of chitosan/Al2O3/Fe3O4 composite beads and nanofibers after five sorption-desorption cycles were carried out. The Box-Behnken design was used to investigate the interaction effects of adsorbent dosage, nitrate and phosphate initial concentrations on the nitrate and phosphate removal efficiency. The pseudo-second-order kinetic model and known Freundlich and Langmuir isotherm models were used to describe the kinetic and equilibrium data of nitrate and phosphate sorption using chitosan/Al2O3/Fe3O4 composite beads and nanofibers. The influence of other anions including chloride, fluoride and sulphate on the sorption efficiency of nitrate and phosphate was examined. The obtained results revealed the higher potential of chitosan/Al2O3/Fe3O4 composite nanofibers for nitrate and phosphate compared with chitosan/Al2O3/Fe3O4 composite beads.

  4. Use of sepiolite as an adsorbent for the removal of copper (II) from industrial waste leachate

    NASA Astrophysics Data System (ADS)

    Gamze Turan, N.; Ardali, Yüksel

    2013-04-01

    as talc, but it has discontinuities and inversion of the silica sheets, which give rise to structural tunnels and blocks. In the inner blocks, all corners of the silica tetrahedral are connected to adjacent blocks, but in the outer blocks, some of the corners are Si atoms bound to hydroxyls (Si-OH). This unique structure allows the penetration of organic and inorganic species into the structure and assigns sepiolite an industrial importance in adsorption. The objective of the present study is to investigate the feasibility of using sepiolite for the adsorptive removal of Cu (II) from the industrial waste leachate. The adsorption capacities and sorption efficiencies are determined. The pseudo first order, the pseudo-second order, Elovich and the intra particle diffusion kinetic models are used to describe the kinetic data to estimate the rate constants. The adsorption of Cu (II) from the aqueous leachate of industrial wastes onto sepiolite was performed using a batch equilibrium technique. At first stage, one-factor-at-a-time experiments were performed to see the individual effects of initial pH, adsorbent dosage and contact time. The adsorption of Cu (II) was favorably influenced by an increase in the adsorbent dosage. The maximum percent removal of Cu (II) were observed at pH>6, and significantly decreased at lower pH value. The optimum contact time is found as 10 min. for the removal of Cu (II). The increment in contact time from 10 min. to 120 min. did not show a significant effect on efficiency. The maximum Cu (II) adsorption efficiencies were obtained at 94.45%. The pseudo second order kinetic model agrees very well with the dynamical behavior for the adsorption of Cu (II) from aqueous leachate of industrial waste onto sepiolite. The results indicate that the use of sepiolite that is locally available and almost free of cost as an adsorbent could be a viable alternative to activated carbon for the removal of Cu (II) ions from aqueous solutions.

  5. The Enigma of Rapamycin Dosage.

    PubMed

    Mukhopadhyay, Suman; Frias, Maria A; Chatterjee, Amrita; Yellen, Paige; Foster, David A

    2016-03-01

    The mTOR pathway is a critical regulator of cell growth, proliferation, metabolism, and survival. Dysregulation of mTOR signaling has been observed in most cancers and, thus, the mTOR pathway has been extensively studied for therapeutic intervention. Rapamycin is a natural product that inhibits mTOR with high specificity. However, its efficacy varies by dose in several contexts. First, different doses of rapamycin are needed to suppress mTOR in different cell lines; second, different doses of rapamycin are needed to suppress the phosphorylation of different mTOR substrates; and third, there is a differential sensitivity of the two mTOR complexes mTORC1 and mTORC2 to rapamycin. Intriguingly, the enigmatic properties of rapamycin dosage can be explained in large part by the competition between rapamycin and phosphatidic acid (PA) for mTOR. Rapamycin and PA have opposite effects on mTOR whereby rapamycin destabilizes and PA stabilizes both mTOR complexes. In this review, we discuss the properties of rapamycin dosage in the context of anticancer therapeutics.

  6. Removal of cationic dyes from aqueous solution using magnetic multi-wall carbon nanotube nanocomposite as adsorbent.

    PubMed

    Gong, Ji-Lai; Wang, Bin; Zeng, Guang-Ming; Yang, Chun-Ping; Niu, Cheng-Gang; Niu, Qiu-Ya; Zhou, Wen-Jin; Liang, Yi

    2009-05-30

    A magnetic multi-wall carbon nanotube (MMWCNT) nanocomposite was synthesized and was used as an adsorbent for removal of cationic dyes from aqueous solutions. The MMWCNT nanocomposite was composed of commercial multi-wall carbon nanotubes and iron oxide nanoparticles. The properties of this magnetic adsorbent were characterized by scanning electron microscopy, X-ray diffraction and BET surface area measurements. Adsorption characteristics of the MMWCNT nanocomposite adsorbent were examined using methylene blue, neutral red and brilliant cresyl blue as adsorbates. Experiments were carried out to investigate adsorption kinetics, adsorption capacity of the adsorbent and the effect of adsorption dosage and solution pH values on the removal of cationic dyes. Kinetic data were well fitted by a pseudo second-order model. Freundlich model was used to study the adsorption isotherms. The prepared MMWCNT adsorbent displayed the main advantage of separation convenience compared to the present adsorption treatment.

  7. Adsorbed Water Illustration

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Thermal and Electrical Conductivity Probe on NASA's Phoenix Mars Lander detected small and variable amounts of water in the Martian soil.

    In this schematic illustration, water molecules are represented in red and white; soil minerals are represented in green and blue. The water, neither liquid, vapor, nor solid, adheres in very thin films of molecules to the surfaces of soil minerals. The left half illustrates an interpretation of less water being adsorbed onto the soil-particle surface during a period when the tilt, or obliquity, of Mars' rotation axis is small, as it is in the present. The right half illustrates a thicker film of water during a time when the obliquity is greater, as it is during cycles on time scales of hundreds of thousands of years. As the humidity of the atmosphere increases, more water accumulates on mineral surfaces. Thicker films behave increasingly like liquid water.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  8. [Dosage forms of phytogenic drugs].

    PubMed

    Luftensteiner, C P; Viernstein, H

    1999-01-01

    Herbal drug formulation is a challenge in pharmaceutical technology due to the complex physicochemical properties of these multicomponent materials. Potential instabilities of the pharmacologically active and coactive substances as well as incompatibilities and interactions of the extracted compounds and excipients have to be considered. Microbial contamination of the applied plant material might limit the shelf life of the products. Using state of the art methods in formulation stable preparations are obtained; additionally compliance of drugs might be enhanced due to simplified application or better sensorial quality. Nowadays, besides traditional pharmacopoeial aqueous, ethanolic, or (partially) dried extracts fluid, semisolid, or solid dosage forms of these extracts are in use, for example syrups, juices, drops, liniments, gels, ointments, creams, suppositories, tablets, coated tablets (dragees) as well as soft and hard gelatine capsules.

  9. Dosage Compensation of the Sex Chromosomes

    PubMed Central

    Disteche, Christine M.

    2013-01-01

    Differentiated sex chromosomes evolved because of suppressed recombination once sex became genetically controlled. In XX/XY and ZZ/ZW systems, the heterogametic sex became partially aneuploid after degeneration of the Y or W. Often, aneuploidy causes abnormal levels of gene expression throughout the entire genome. Dosage compensation mechanisms evolved to restore balanced expression of the genome. These mechanisms include upregulation of the heterogametic chromosome as well as repression in the homogametic sex. Remarkably, strategies for dosage compensation differ between species. In organisms where more is known about molecular mechanisms of dosage compensation, specific protein complexes containing noncoding RNAs are targeted to the X chromosome. In addition, the dosage-regulated chromosome often occupies a specific nuclear compartment. Some genes escape dosage compensation, potentially resulting in sex-specific differences in gene expression. This review focuses on dosage compensation in mammals, with comparisons to fruit flies, nematodes, and birds. PMID:22974302

  10. Mechanisms of X Chromosome Dosage Compensation

    PubMed Central

    Ercan, Sevinç

    2015-01-01

    In many animals, males have one X and females have two X chromosomes. The difference in X chromosome dosage between the two sexes is compensated by mechanisms that regulate X chromosome transcription. Recent advances in genomic techniques have provided new insights into the molecular mechanisms of X chromosome dosage compensation. In this review, I summarize our current understanding of dosage imbalance in general, and then review the molecular mechanisms of X chromosome dosage compensation with an emphasis on the parallels and differences between the three well-studied model systems, M. musculus, D. melanogaster and C. elegans. PMID:25628761

  11. Comparative studies on removal of Erythrosine using ZnS and AgOH nanoparticles loaded on activated carbon as adsorbents: Kinetic and isotherm studies of adsorption

    NASA Astrophysics Data System (ADS)

    Ghaedi, M.; Rozkhoosh, Z.; Asfaram, A.; Mirtamizdoust, B.; Mahmoudi, Z.; Bazrafshan, A. A.

    2015-03-01

    Erythrosine adsorption (Er) onto ZnS and AgOH nanoparticle-loaded activated carbon (ZnS-NP-AC and AgOH-NP-AC) was studied and results were compared. Subsequent preparation were fully analyzed by different approach such as BET to obtain knowledge about surface area, pore volume, while FT-IR analysis give comprehensive information about functional group the dependency of removal percentage to adsorbent mass, initial Er concentration and contact time were investigated and optimum conditions for pH, adsorbent dosage, Er concentration and contact time was set as be 3.2, 0.016 g, 20 mg/L and 16 min and 3.2, 0.015 g, 19 mg/L and 2 min for ZnS-NP-AC and AgOH-NP-AC, respectively. The equilibrium data correspond to adsorption strongly follow Langmuir model by ZnS-NP-AC and Freundlich model for AgOH-NP-AC. High adsorption capacity for of 55.86-57.80 mg g-1 and 67.11-89.69 mg g-1 for ZnS-NP-AC and AgOH-NP-AC, respectively. The result of present study confirm the applicability of small amount of these adsorbent (<0.02 g) for efficient removal of Er (>95%) in short reasonable time (20 min).

  12. Comparative studies on removal of Erythrosine using ZnS and AgOH nanoparticles loaded on activated carbon as adsorbents: Kinetic and isotherm studies of adsorption.

    PubMed

    Ghaedi, M; Rozkhoosh, Z; Asfaram, A; Mirtamizdoust, B; Mahmoudi, Z; Bazrafshan, A A

    2015-03-05

    Erythrosine adsorption (Er) onto ZnS and AgOH nanoparticle-loaded activated carbon (ZnS-NP-AC and AgOH-NP-AC) was studied and results were compared. Subsequent preparation were fully analyzed by different approach such as BET to obtain knowledge about surface area, pore volume, while FT-IR analysis give comprehensive information about functional group the dependency of removal percentage to adsorbent mass, initial Er concentration and contact time were investigated and optimum conditions for pH, adsorbent dosage, Er concentration and contact time was set as be 3.2, 0.016g, 20mg/L and 16min and 3.2, 0.015g, 19mg/L and 2min for ZnS-NP-AC and AgOH-NP-AC, respectively. The equilibrium data correspond to adsorption strongly follow Langmuir model by ZnS-NP-AC and Freundlich model for AgOH-NP-AC. High adsorption capacity for of 55.86-57.80mgg(-1) and 67.11-89.69mgg(-1) for ZnS-NP-AC and AgOH-NP-AC, respectively. The result of present study confirm the applicability of small amount of these adsorbent (<0.02g) for efficient removal of Er (>95%) in short reasonable time (20min).

  13. MTBE adsorption on alternative adsorbents and packed bed adsorber performance.

    PubMed

    Rossner, Alfred; Knappe, Detlef R U

    2008-04-01

    Widespread use of the fuel additive methyl tertiary-butyl ether (MTBE) has led to frequent MTBE detections in North American and European drinking water sources. The overall objective of this research was to evaluate the effectiveness of a silicalite zeolite, a carbonaceous resin, and a coconut-shell-based granular activated carbon (GAC) for the removal of MTBE from water. Isotherm and short bed adsorber tests were conducted in ultrapure water and river water to obtain parameters describing MTBE adsorption equilibria and kinetics and to quantify the effect of natural organic matter (NOM) on MTBE adsorption. Both the silicalite zeolite and the carbonaceous resin exhibited larger MTBE adsorption uptakes than the tested GAC. Surface diffusion coefficients describing intraparticle MTBE mass transfer rates were largest for the GAC and smallest for the carbonaceous resin. Pilot tests were conducted to verify MTBE breakthrough curve predictions obtained with the homogeneous surface diffusion model and to evaluate the effect of NOM preloading on packed bed adsorber performance. Results showed that GAC was the most cost-competitive adsorbent when considering adsorbent usage rate only; however, the useful life of an adsorber containing silicalite zeolite was predicted to be approximately 5-6 times longer than that of an equally sized adsorber containing GAC. Pilot column results also showed that NOM preloading did not impair the MTBE removal efficiency of the silicalite zeolite. Thus, it may be possible to regenerate spent silicalite with less energy-intensive methods than those required to regenerate GAC.

  14. Schiff base - Chitosan grafted L-monoguluronic acid as a novel solid-phase adsorbent for removal of congo red.

    PubMed

    Yuan, Bo; Qiu, Li-Gan; Su, Hong-Zhen; Cao, Cheng-Liang; Jiang, Ji-Hong

    2016-01-01

    A novel modified chitosan adsorbent (GL-SBCS) was synthesized by covalently grafting a Schiff base-chitosan (SBCS) onto the surface of l-monoguluronic acid. Physico-chemical investigation on the adsorption of congo red, an anionic azo dye by GL-SBCS has been carried out. The effect of different weight contents of chitosan in GL-SBCS composite, adsorbent dosage, initial pH and contract time were studied in detail using batch adsorption. Results showed that GL-SBCS exhibited better than normal CS and l-monoguluronic acid. Further investigation demonstrated that the adsorption pattern fitted well with the Langmuir model (R(2)>0.99) but less-satisfied the Freundlich model. Both ionic interaction as well as physical forces is responsible for binding of congo red with GL-SBCS as determined by zeta potential measurement Both sodium chloride and sodium dodecyl sulfate significantly influenced the adsorption process. SBCS would be a good method and resource to increase absorption efficiency for the removal of anionic dyes in a wastewater treatment process.

  15. Local anesthetics adsorbed onto infusion balloon.

    PubMed

    Mizogami, Maki; Tsuchiya, Hironori; Takakura, Ko

    2004-09-01

    We compared the adsorption of different local anesthetics onto infusion balloons and studied one of the possible mechanisms for adsorption. After injection of lidocaine, bupivacaine, ropivacaine, and mepivacaine solutions (1 mM each; pH 7.4) into balloons of 100-mL volume, their concentrations in effluents flowing out at 4 mL/h were determined over time by high-performance liquid chromatography. All were adsorbed in a structure-dependent manner, and the concentration decreased by 6%-14% within 5 min. Bupivacaine was most strongly adsorbed, followed by lidocaine, ropivacaine, and mepivacaine. QX-314, a quaternary ammonium derivative of lidocaine, was only weakly adsorbed compared with the parent compound lidocaine. The extent of adsorption of local anesthetics was related to their hydrophobicity (evaluated by reversed-phase chromatography) and was much more at pH 7.4 than at pH 6.0. A hydrophobic interaction with balloon materials appears to be responsible for the adsorption of local anesthetics. When infusion balloons are used for the continuous administration of local anesthetics, attention should be paid to the possibility that their actual concentrations in effluents are smaller than those present when they are initially prepared.

  16. Uniform magnesium oxide adsorbents

    NASA Technical Reports Server (NTRS)

    Dash, J. G.; Ecke, R.; Stoltenberg, J.; Vilches, O. E.; Whittemore, O. J., Jr.

    1978-01-01

    Kr adsorption on MgO is used to characterize the surface uniformity of MgO smoke and thermally decomposed Mg(OH)2. It is found that initially heterogeneous samples develop progressively sharper stepwise isotherms with increasingly-high-temperature heat treatment, apparently due to the removal of imperfections and high-energy facets, leaving surfaces of highly uniform (100) planes.

  17. [Pharmaceutical advice concerning different pharmaceutical dosage forms].

    PubMed

    Szakonyi, Gergely; Zelkó, Romána

    2010-01-01

    The present paper summarizes the commonly applied types of drug uptake and the pharmacists' advice concerning a certain dosage form. The manuscript also deals with the modified release dosage forms and their abbreviations in the name of the marketing authorized products.

  18. Rotary adsorbers for continuous bulk separations

    DOEpatents

    Baker, Frederick S [Oak Ridge, TN

    2011-11-08

    A rotary adsorber for continuous bulk separations is disclosed. The rotary adsorber includes an adsorption zone in fluid communication with an influent adsorption fluid stream, and a desorption zone in fluid communication with a desorption fluid stream. The fluid streams may be gas streams or liquid streams. The rotary adsorber includes one or more adsorption blocks including adsorbent structure(s). The adsorbent structure adsorbs the target species that is to be separated from the influent fluid stream. The apparatus includes a rotary wheel for moving each adsorption block through the adsorption zone and the desorption zone. A desorption circuit passes an electrical current through the adsorbent structure in the desorption zone to desorb the species from the adsorbent structure. The adsorbent structure may include porous activated carbon fibers aligned with their longitudinal axis essentially parallel to the flow direction of the desorption fluid stream. The adsorbent structure may be an inherently electrically-conductive honeycomb structure.

  19. Physicochemical interactions in solid dosage forms.

    PubMed

    Narang, Ajit S; Desai, Divyakant; Badawy, Sherif

    2012-10-01

    Complete characterization and mechanistic understanding of physicochemical interactions in solid dosage forms are not only important for consistent manufacturability, stability, and bioavailability of the drug product, but are also expected under the quality-by-design paradigm of drug development. Lack of this understanding can impact successful and timely development, scale-up, and commercial manufacture of dosage forms. This article highlights the stability and bioavailability implications of physicochemical interactions in dosage forms citing a couple of examples where such interactions necessitated the recall of commercial drug products.

  20. Terminology challenges: defining modified release dosage forms in veterinary medicine.

    PubMed

    Martinez, Marilyn N; Lindquist, Danielle; Modric, Sanja

    2010-08-01

    Terminologies for describing dosage form release characteristics for human pharmaceuticals have been addressed by bodies such as the US Food and Drug Administration (FDA), the International Conference on Harmonization (ICH), and the US Pharmacopeia (USP). While the definition for terms such as "immediate release," "modified release," "extended release," and "delayed release" are now well accepted for human pharmaceuticals, confusion still exists within the veterinary community. In part, this confusion is attributable to differences between human and veterinary dosage forms (such as the preponderance of parenteral vs. oral extended release products for use in animals vs. the focus on oral extended release formulations for human use) which reflect interspecies differences in physiology and conditions of use. It also simply reflects a lack of attention to existing definitions. In an effort to remedy this problem, this manuscript reflects an initial effort to suggest definitions that may be appropriate for describing formulation effects in veterinary medicine.

  1. Uremic toxins and oral adsorbents.

    PubMed

    Goto, Shunsuke; Yoshiya, Kunihiko; Kita, Tomoyuki; Fujii, Hideki; Fukagawa, Masafumi

    2011-04-01

    Uremic toxins are associated with various disorders in patients with end-stage renal disease and it is difficult to remove some of these toxins by dialysis. Since some uremic toxins are generated by bacterial metabolites in the colon, oral adsorbents that interfere with the absorption of uremic toxins or their precursors are believed to prevent their accumulation in the body. AST-120 adsorbs various uremic retention solutes in the gastrointestinal system and has potential for providing clinical benefit. Sevelamer hydrochloride binds some harmful compounds in addition to phosphate and seems to have pleiotropic effects that include lowering serum LDL cholesterol levels and reduction of inflammation. The effect of sevelamer hydrochloride on indoxyl sulfate and p-cresol has been shown in an in vitro study; however, in vivo studies in mice or humans did not demonstrate this effect on protein-binding uremic toxins. Oral adsorbents are thus one of the important modalities in the treatment of uremic syndrome.

  2. Conformational changes of adsorbed proteins

    NASA Astrophysics Data System (ADS)

    Allen, Scott

    2005-03-01

    The adsorption of bovine serum albumin (BSA) and pepsin to gold surfaces has been studied using surface plasmon resonance (SPR). Proteins are adsorbed from solution onto a gold surface and changes in the conformation of the adsorbed proteins are induced by changing the buffer solution. We selected pH and ionic strength values for the buffer solutions that are known from our circular dichroism measurements to cause conformational changes of the proteins in bulk solution. We find that for both BSA and pepsin the changes in conformation are impeded by the interaction of the protein with the gold surface.

  3. Ammonium removal from aqueous solutions by using natural Chinese (Chende) zeolite as adsorbent.

    PubMed

    Huang, Haiming; Xiao, Xianming; Yan, Bo; Yang, Liping

    2010-03-15

    This paper presents a study of the removal of ammonium ion from aqueous solutions using natural Chinese (Chende) zeolite. A series of experiments was conducted to examine the effects of solution pH, particle size, contact time, adsorbent dosage, and the presence of other cation- and anion species on ammonium removal. The findings indicated that these parameters named had a significant effect on the removal of ammonium by the zeolite. The effect of other cations on the removal of ammonium followed the order of preference Na(+)>K(+)>Ca(2+)>Mg(2+) at identical mass concentrations, and the effect of the presence of individual anions followed the order of preference carbonate>chloride>sulfate>phosphate at identical mass concentrations of ammonium ions. Kinetic analysis showed that the adsorption of ammonium on zeolite at different ranges of particle size well followed the pseudo-second-order model and followed the intra-particle diffusion model only during the initial 60 min of the adsorption process. Equilibrium isotherm data was fitted to the linear Langmuir- and Freundlich models with the latter model providing the better description of the process (R(2)=0.991-0.997) compared to the former (R(2)=0.902-0.989).

  4. 21 CFR 526.464 - Cloxacillin intramammary dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Cloxacillin intramammary dosage forms. 526.464... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS INTRAMAMMARY DOSAGE FORMS § 526.464 Cloxacillin intramammary dosage forms....

  5. Adsorbent Alkali Conditioning for Uranium Adsorption from Seawater. Adsorbent Performance and Technology Cost Evaluation

    SciTech Connect

    Tsouris, Costas; Mayes, Richard T.; Janke, Christopher James; Dai, Sheng; Das, S.; Liao, W. -P.; Kuo, Li-Jung; Wood, Jordana; Gill, Gary; Byers, Maggie Flicker; Schneider, Eric

    2015-09-30

    The Fuel Resources program of the Fuel Cycle Research and Development program of the Office of Nuclear Energy (NE) is focused on identifying and implementing actions to assure that nuclear fuel resources are available in the United States. An immense source of uranium is seawater, which contains an estimated amount of 4.5 billion tonnes of dissolved uranium. This unconventional resource can provide a price cap and ensure centuries of uranium supply for future nuclear energy production. NE initiated a multidisciplinary program with participants from national laboratories, universities, and research institutes to enable technical breakthroughs related to uranium recovery from seawater. The goal is to develop advanced adsorbents to reduce the seawater uranium recovery technology cost and uncertainties. Under this program, Oak Ridge National Laboratory (ORNL) has developed a new amidoxime-based adsorbent of high surface area, which tripled the uranium capacity of leading Japanese adsorbents. Parallel efforts have been focused on the optimization of the physicochemical and operating parameters used during the preparation of the adsorbent for deployment. A set of parameters that need to be optimized are related to the conditioning of the adsorbent with alkali solution, which is necessary prior to adsorbent deployment. Previous work indicated that alkali-conditioning parameters significantly affect the adsorbent performance. Initiated in 2014, this study had as a goal to determine optimal parameters such as base type and concentration, temperature, and duration of conditioning that maximize the uranium adsorption performance of amidoxime functionalized adsorbent, while keeping the cost of uranium production low. After base-treatment at various conditions, samples of adsorbent developed at ORNL were tested in this study with batch simulated seawater solution of 8-ppm uranium concentration, batch seawater spiked with uranium nitrate at 75-100 ppb uranium, and continuous

  6. Dosage Compensation of the Drosophila White Gene Requires Both the X Chromosome Environment and Multiple Intragenic Elements

    PubMed Central

    Qian, S.; Pirrotta, V.

    1995-01-01

    The X-linked white gene when transposed to autosomes retains only partial dosage compensation. One copy of the gene in males expresses more than one copy but less than two copies in females. When inserted in ectopic X chromosome sites, the mini-white gene of the CaspeR vector can be fully dosage compensated and can even achieve hyperdosage compensation, meaning that one copy in males gives more expression than two copies in females. As sequences are removed gradually from the 5' end of the gene, we observe a progressive transition from hyperdosage compensation to full dosage compensation to partial dosage compensation. When the deletion reaches -17, the gene can no longer dosage compensate fully even on the X chromosome. A deletion reaching +173, 4 bp preceeding the AUG initiation codon, further reduces dosage compensation both on the X chromosome and on autosomes. This truncated gene can still partially dosage compensate on autosomes, indicating the presence of dosage compensation determinants in the protein coding region. We conclude that full dosage compensation requires an X chromosome environment and that the white gene contains multiple dosage-compensation determinants, some near the promoter and some in the coding region. PMID:7713428

  7. Dosage compensation of the Drosophila white gene requires both the X chromosome environment and multiple intragenic elements

    SciTech Connect

    Qian, S.; Pirrotta, V.

    1995-02-01

    The X-linked white gene when transposed to autosomes retains only partial dosage compensation. One copy of the gene in males expresses more than one copy but less than two copies in females. When inserted in ectopic X chromosome sites, the mini-white gene of the CaspeR vector can be fully dosage compensated and can even achieve hyperdosage compensation, meaning that one copy in males gives more expression than two copies in females. As sequences are removed gradually from the 5{prime} end of the gene, we observe a progressive transition from hyperdosage compensation to full dosage compensation to partial dosage compensation. When the deletion reaches -17, the gene can no longer dosage compensate fully even on the X chromosome. A deletion reaching +173, 4 bp preceeding the AUG initiation codon, further reduces dosage compensation both on the X chromosome and on autosomes. This truncated gene can still partially dosage compensate on autosomes, indicating the presence of dosage compensation determinants in the protein coding region. We conclude that full dosage compensation requires an X chromosome environment and that the white gene contains multiple dosage-compensation determinants, some near the promoter and some in the coding region. 48 refs., 4 figs., 2 tabs.

  8. Mass transport of adsorbates near a discontinuous structural phase transition

    NASA Astrophysics Data System (ADS)

    Granato, E.; Ying, S. C.; Elder, K. R.; Ala-Nissila, T.

    2016-12-01

    We study the mass transport dynamics of an adsorbed layer near a discontinuous incommensurate striped-honeycomb phase transition via numerical simulations of a coarse-grained model focusing on the motion of domain walls rather than individual atoms. Following an initial step profile created in the incommensurate striped phase, an intermediate hexagonal incommensurate phase nucleates and grows, leading to a bifurcation into two sharp profiles propagating in opposite directions as opposed to broad profiles induced by atomic diffusive motion. Our results are in agreement with recent numerical simulations of a microscopic model as well as experimental observations for the Pb/Si(111) adsorbate system.

  9. [Dosage compensation mechanism of X chromosome].

    PubMed

    Wang, Yan-Yun; Chen, Mei; Li, Bin

    2012-08-01

    Dosage compensation mechanism is crucial for the balance expression of X chromosome genes, which ensures the protein or enzyme encoded by the X chromosome to be equal or almost equal expression amounts between males and females. However, different organisms have evolved distinct dosage compensation strategies, and so far three kinds of dosage compensation strategies among organisms have been reported. The first strategy is that the single male X chromosome expression is doubly activated; the second one is to inactivate one female X chromosome by leaving both sexes with one active allele; and the third one is to reduce the expression to half activity in both X chromosomes of the female. The study of dosage compensation will be useful to reveal the mechanism of regulation of X-linked genes as well as the evolution and the differentiation progress of the sex chromosome, and it can also contribute to illustrate mutation and distortion of sex chromosome. Therefore, this paper briefly reviewed and discussed the progresses and prospects of the important mechanism of dosage compensation.

  10. Differential replication dynamics for large and small Vibrio chromosomes affect gene dosage, expression and location

    PubMed Central

    Dryselius, Rikard; Izutsu, Kaori; Honda, Takeshi; Iida, Tetsuya

    2008-01-01

    Background Replication of bacterial chromosomes increases copy numbers of genes located near origins of replication relative to genes located near termini. Such differential gene dosage depends on replication rate, doubling time and chromosome size. Although little explored, differential gene dosage may influence both gene expression and location. For vibrios, a diverse family of fast growing gammaproteobacteria, gene dosage may be particularly important as they harbor two chromosomes of different size. Results Here we examined replication dynamics and gene dosage effects for the separate chromosomes of three Vibrio species. We also investigated locations for specific gene types within the genome. The results showed consistently larger gene dosage differences for the large chromosome which also initiated replication long before the small. Accordingly, large chromosome gene expression levels were generally higher and showed an influence from gene dosage. This was reflected by a higher abundance of growth essential and growth contributing genes of which many locate near the origin of replication. In contrast, small chromosome gene expression levels were low and appeared independent of gene dosage. Also, species specific genes are highly abundant and an over-representation of genes involved in transcription could explain its gene dosage independent expression. Conclusion Here we establish a link between replication dynamics and differential gene dosage on one hand and gene expression levels and the location of specific gene types on the other. For vibrios, this relationship appears connected to a polarisation of genetic content between its chromosomes, which may both contribute to and be enhanced by an improved adaptive capacity. PMID:19032792

  11. Active compounds release from semisolid dosage forms.

    PubMed

    Olejnik, Anna; Goscianska, Joanna; Nowak, Izabela

    2012-11-01

    The aim of this paper is to review all the aspects of the in vitro release testing (IVRT) from semisolid dosage forms. Although none of the official dissolution methods has been specified for use with semisolid dosage forms, their utility for assessing release rates of drugs from semisolid dosage forms has become a topic of considerable interest. One can expect to overcome such complexity in the future, when the official "Topical and Transdermal Drug Products-Product Performance Tests" will be published in an issue of the Pharmacopeial Forum. Many factors such as type of the dissolution medium, membrane, temperature, and speed have an influence on the mechanism and kinetics of the release testing from gels, creams, and ointments; therefore, those parameters have been widely discussed.

  12. Prescribing Errors Involving Medication Dosage Forms

    PubMed Central

    Lesar, Timothy S

    2002-01-01

    CONTEXT Prescribing errors involving medication dose formulations have been reported to occur frequently in hospitals. No systematic evaluations of the characteristics of errors related to medication dosage formulation have been performed. OBJECTIVE To quantify the characteristics, frequency, and potential adverse patient effects of prescribing errors involving medication dosage forms . DESIGN Evaluation of all detected medication prescribing errors involving or related to medication dosage forms in a 631-bed tertiary care teaching hospital. MAIN OUTCOME MEASURES Type, frequency, and potential for adverse effects of prescribing errors involving or related to medication dosage forms. RESULTS A total of 1,115 clinically significant prescribing errors involving medication dosage forms were detected during the 60-month study period. The annual number of detected errors increased throughout the study period. Detailed analysis of the 402 errors detected during the last 16 months of the study demonstrated the most common errors to be: failure to specify controlled release formulation (total of 280 cases; 69.7%) both when prescribing using the brand name (148 cases; 36.8%) and when prescribing using the generic name (132 cases; 32.8%); and prescribing controlled delivery formulations to be administered per tube (48 cases; 11.9%). The potential for adverse patient outcome was rated as potentially “fatal or severe” in 3 cases (0.7%), and “serious” in 49 cases (12.2%). Errors most commonly involved cardiovascular agents (208 cases; 51.7%). CONCLUSIONS Hospitalized patients are at risk for adverse outcomes due to prescribing errors related to inappropriate use of medication dosage forms. This information should be considered in the development of strategies to prevent adverse patient outcomes resulting from such errors. PMID:12213138

  13. Biodegradable metal adsorbent synthesized by graft polymerization onto nonwoven cotton fabric

    NASA Astrophysics Data System (ADS)

    Sekine, Ayako; Seko, Noriaki; Tamada, Masao; Suzuki, Yoshio

    2010-01-01

    A fibrous adsorbent for Hg ions was synthesized by radiation-induced emulsion graft polymerization of glycidyl methacrylate (GMA) onto a nonwoven cotton fabric and subsequent chemical modification. The optimal pre-irradiation dose for initiation of the graft polymerization of GMA, which minimized the effects of radiation damage on the mechanical strength of the nonwoven cotton fabric, was found to be 10 kGy. The GMA-grafted nonwoven cotton fabric was subsequently modified with ethylenediamine (EDA) or diethylenetriamine (DETA) to obtain a Hg adsorbent. The resulting amine-type adsorbents were evaluated for batch and continuous adsorption of Hg. In batch adsorption, the distribution coefficients of Hg reached 1.9×10 5 and 1.0×10 5 for EDA- and DETA-type adsorbents, respectively. A column packed with EDA-type adsorbent removed Hg from 1.8 ppm Hg solution at a space velocity of 100 h -1, which corresponds to 16,000 times the volume of the packed adsorbent. The adsorbed Hg on the EDA-type adsorbent could be completely eluted by 1 M HCl solution. A microbial oxidative degradation test revealed that the EDA-type adsorbent is biodegradable.

  14. Ensemble Simulations with Coupled Atmospheric Dynamic and Dispersion Models: Illustrating Uncertainties in Dosage Simulations.

    NASA Astrophysics Data System (ADS)

    Warner, Thomas T.; Sheu, Rong-Shyang; Bowers, James F.; Sykes, R. Ian; Dodd, Gregory C.; Henn, Douglas S.

    2002-05-01

    Ensemble simulations made using a coupled atmospheric dynamic model and a probabilistic Lagrangian puff dispersion model were employed in a forensic analysis of the transport and dispersion of a toxic gas that may have been released near Al Muthanna, Iraq, during the Gulf War. The ensemble study had two objectives, the first of which was to determine the sensitivity of the calculated dosage fields to the choices that must be made about the configuration of the atmospheric dynamic model. In this test, various choices were used for model physics representations and for the large-scale analyses that were used to construct the model initial and boundary conditions. The second study objective was to examine the dispersion model's ability to use ensemble inputs to predict dosage probability distributions. Here, the dispersion model was used with the ensemble mean fields from the individual atmospheric dynamic model runs, including the variability in the individual wind fields, to generate dosage probabilities. These are compared with the explicit dosage probabilities derived from the individual runs of the coupled modeling system. The results demonstrate that the specific choices made about the dynamic-model configuration and the large-scale analyses can have a large impact on the simulated dosages. For example, the area near the source that is exposed to a selected dosage threshold varies by up to a factor of 4 among members of the ensemble. The agreement between the explicit and ensemble dosage probabilities is relatively good for both low and high dosage levels. Although only one ensemble was considered in this study, the encouraging results suggest that a probabilistic dispersion model may be of value in quantifying the effects of uncertainties in a dynamic-model ensemble on dispersion model predictions of atmospheric transport and dispersion.

  15. Removal of lead and zinc ions from water by low cost adsorbents.

    PubMed

    Mishra, P C; Patel, R K

    2009-08-30

    In this study, activated carbon, kaolin, bentonite, blast furnace slag and fly ash were used as adsorbent with a particle size between 100 mesh and 200 mesh to remove the lead and zinc ions from water. The concentration of the solutions prepared was in the range of 50-100 mg/L for lead and zinc for single and binary systems which are diluted as required for batch experiments. The effect of contact time, pH and adsorbent dosage on removal of lead and zinc by adsorption was investigated. The equilibrium time was found to be 30 min for activated carbon and 3h for kaolin, bentonite, blast furnace slag and fly ash. The most effective pH value for lead and zinc removal was 6 for activated carbon. pH value did not effect lead and zinc removal significantly for other adsorbents. Adsorbent doses were varied from 5 g/L to 20 g/L for both lead and zinc solutions. An increase in adsorbent doses increases the percent removal of lead and zinc. A series of isotherm studies was undertaken and the data evaluated for compliance was found to match with the Langmuir and Freundlich isotherm models. To investigate the adsorption mechanism, the kinetic models were tested, and it follows second order kinetics. Kinetic studies reveals that blast furnace slag was not effective for lead and zinc removal. The bentonite and fly ash were effective for lead and zinc removal.

  16. Solid-state conversion of fly ash to effective adsorbents for Cu removal from wastewater.

    PubMed

    Wang, Shaobin; Li, Lin; Zhu, Z H

    2007-01-10

    Solid-state conversion of fly ash to an amorphous aluminosilicate adsorbent (geopolymer) has been investigated under different conditions and the synthesised material has been tested for Cu2+ removal from aqueous solution. It has been found that higher reaction temperature and Na:FA ratio will make the adsorbents achieving higher removal efficiency. The adsorbent loading and Cu2+ initial concentration will also affect the removal efficiency while the adsorption capacity exhibits similarly at 30-40 degrees C. The adsorption capacity of the synthesised adsorbent shows much higher value than fly ash and natural zeolite. The capacity is 0.1, 3.5 and 92 mg/g, for fly ash, natural zeolite, and FA derived adsorbent, respectively. The kinetic studies indicate that the adsorption can be fitted by the second-order kinetic model. Langmuir and Freundlich isotherms also can fit to the adsorption isotherm.

  17. A novel fiber-based adsorbent technology

    SciTech Connect

    Reynolds, T.A.

    1997-10-01

    In this Phase I Small Business Innovation Research program, Chemica Technologies, Inc. is developing an economical, robust, fiber-based adsorbent technology for removal of heavy metals from contaminated water. The key innovation is the development of regenerable adsorbent fibers and adsorbent fiber cloths that have high capacity and selectivity for heavy metals and are chemically robust. The process has the potential for widespread use at DOE facilities, mining operations, and the chemical process industry.

  18. Basics of compounding foam dosage forms.

    PubMed

    Allen, Loyd V

    2013-01-01

    The purpose of this article is to provide information on the use of foam dosage forms and pharmacists' ability to extemporaneously compound them. The article provides: (1) a discussion on the rationale and advantages of using foams, (2) a differentiation between the various types and structures of foams, (3) a list of the various types of ingredients and examples of each, and (4) a description of the preparation of pharmaceutical foams.

  19. Risk factors and safe dosage of levodopa for wearing-off phenomenon in Chinese patients with Parkinson's disease.

    PubMed

    Chen, Huimin; Fang, Jinping; Li, Fangfei; Gao, Liyan; Feng, Tao

    2015-07-01

    The objective of this study was to investigate the risk factors of wearing-off phenomenon in Parkinson's disease (PD) and propose safe dosage of levodopa to reduce wearing-off development based on Chinese cohort. Patients with PD who had taken levodopa (L-dopa) for at least 1 month were recruited. Wearing-off was diagnosed based on validated Chinese version of a patient self-rated 9-question Wearing-Off Questionnaire (WOQ-9) and clinical definition. Eleven variables (gender, disease duration at L-dopa initiation, disease duration at assessment, age at onset, age at assessment, H-Y stage, UPDRS III, L-dopa daily total dosage and dosage adjusted to weight, duration of L-dopa treatment, initial drug recipe) were included in our analysis. Univariate analysis, multivariate logistic regression analysis and decision tree classification model(DTC) were used to detect risk factors of wearing-off. Receiver operating characteristic (ROC) curve and DTC were used to investigate cut-off value of L-dopa to best predict wearing-off. Two hundred and thirty-four patients were investigated in our study, among whom 111 developed wearing-off. Patients with wearing-off tended to receive higher L-dopa dosage and endure longer duration of L-dopa treatment. L-Dopa dosage as 281 mg/day and 4.2 mg/kg/day by ROC, as well as 269 mg/day and 3.2 mg/kg/day by DTC were cut-off values for wearing-off. L-Dopa dosage and duration of L-dopa treatment were related to increased wearing-off development. Cumulative L-dopa dosage and L-dopa daily dosage were better predictive of wearing-off. Inadequate evidence was present for delayed L-dopa initiation. L-Dopa daily dosage no more than 275 mg or 4.2 mg/kg was regarded as safe.

  20. Molecularly Imprinted Filtering Adsorbents for Odor Sensing

    PubMed Central

    Shinohara, Sho; Chiyomaru, You; Sassa, Fumihiro; Liu, Chuanjun; Hayashi, Kenshi

    2016-01-01

    Versatile odor sensors that can discriminate among huge numbers of environmental odorants are desired in many fields, including robotics, environmental monitoring, and food production. However, odor sensors comparable to an animal’s nose have not yet been developed. An animal’s olfactory system recognizes odor clusters with specific molecular properties and uses this combinatorial information in odor discrimination. This suggests that measurement and clustering of odor molecular properties (e.g., polarity, size) using an artificial sensor is a promising approach to odor sensing. Here, adsorbents composed of composite materials with molecular recognition properties were developed for odor sensing. The selectivity of the sensor depends on the adsorbent materials, so specific polymeric materials with particular solubility parameters were chosen to adsorb odorants with various properties. The adsorption properties of the adsorbents could be modified by mixing adsorbent materials. Moreover, a novel molecularly imprinted filtering adsorbent (MIFA), composed of an adsorbent substrate covered with a molecularly imprinted polymer (MIP) layer, was developed to improve the odor molecular recognition ability. The combination of the adsorbent and MIP layer provided a higher specificity toward target molecules. The MIFA thus provides a useful technique for the design and control of adsorbents with adsorption properties specific to particular odor molecules. PMID:27886070

  1. Emergence of 3D Printed Dosage Forms: Opportunities and Challenges.

    PubMed

    Alhnan, Mohamed A; Okwuosa, Tochukwu C; Sadia, Muzna; Wan, Ka-Wai; Ahmed, Waqar; Arafat, Basel

    2016-08-01

    The recent introduction of the first FDA approved 3D-printed drug has fuelled interest in 3D printing technology, which is set to revolutionize healthcare. Since its initial use, this rapid prototyping (RP) technology has evolved to such an extent that it is currently being used in a wide range of applications including in tissue engineering, dentistry, construction, automotive and aerospace. However, in the pharmaceutical industry this technology is still in its infancy and its potential yet to be fully explored. This paper presents various 3D printing technologies such as stereolithographic, powder based, selective laser sintering, fused deposition modelling and semi-solid extrusion 3D printing. It also provides a comprehensive review of previous attempts at using 3D printing technologies on the manufacturing dosage forms with a particular focus on oral tablets. Their advantages particularly with adaptability in the pharmaceutical field have been highlighted, which enables the preparation of dosage forms with complex designs and geometries, multiple actives and tailored release profiles. An insight into the technical challenges facing the different 3D printing technologies such as the formulation and processing parameters is provided. Light is also shed on the different regulatory challenges that need to be overcome for 3D printing to fulfil its real potential in the pharmaceutical industry.

  2. Risk assessment and technical feasibility of usage of paper mill sludge biochar-based exhausted adsorbent for geopolymeric brick formation.

    PubMed

    Devi, Parmila; Saroha, Anil K

    2016-11-01

    Risk assessment and technical feasibility of brick formation from exhausted paper mill sludge derived biochar obtained after its use as an adsorbent for the treatment of effluent containing pentachlorophenol was studied. The bricks were prepared by geopolymerization mechanism in presence of sodium hydroxide, and the extent of geopolymerization was determined on the basis of crystal structure, surface functionalities, and surface morphology of the bricks. The preparation parameters (sodium hydroxide dosage, initial water and calcium carbonate content and curing temperature) were optimized and the results were analyzed in terms of compressive strength, water absorption, and abrasion index. Risk assessment of heavy metals was performed to determine the contamination level and overall hazard index of the biochar-based geopolymer bricks. Hazard quotient and hazard index were calculated to assess the overall non-carcinogenic risk posed by selected heavy metals via ingestion and dermal contact. The leaching potential of heavy metal and pentachlorophenol from the biochar-based geopolymer bricks was also determined. The results showed that the biochar-based geopolymer bricks showed good mechanical properties and the concentration of heavy metals in the leachate falls within the permissible limits prescribed by Indian Standards for Industrial and Sewage Effluents Discharge (inland surface water).

  3. Estimated Maximal Safe Dosages of Tumescent Lidocaine

    PubMed Central

    Jeske, Daniel R.

    2016-01-01

    BACKGROUND: Tumescent lidocaine anesthesia consists of subcutaneous injection of relatively large volumes (up to 4 L or more) of dilute lidocaine (≤1 g/L) and epinephrine (≤1 mg/L). Although tumescent lidocaine anesthesia is used for an increasing variety of surgical procedures, the maximum safe dosage is unknown. Our primary aim in this study was to measure serum lidocaine concentrations after subcutaneous administration of tumescent lidocaine with and without liposuction. Our hypotheses were that even with large doses (i.e., >30 mg/kg), serum lidocaine concentrations would be below levels associated with mild toxicity and that the concentration-time profile would be lower after liposuction than without liposuction. METHODS: Volunteers participated in 1 to 2 infiltration studies without liposuction and then one study with tumescent liposuction totally by local anesthesia. Serum lidocaine concentrations were measured at 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, and 24 hours after each tumescent lidocaine infiltration. Area under the curve (AUC∞) of the serum lidocaine concentration-time profiles and peak serum lidocaine concentrations (Cmax) were determined with and without liposuction. For any given milligram per kilogram dosage, the probability that Cmax >6 μg/mL, the threshold for mild lidocaine toxicity was estimated using tolerance interval analysis. RESULTS: In 41 tumescent infiltration procedures among 14 volunteer subjects, tumescent lidocaine dosages ranged from 19.2 to 52 mg/kg. Measured serum lidocaine concentrations were all <6 μg/mL over the 24-hour study period. AUC∞s with liposuction were significantly less than those without liposuction (P = 0.001). The estimated risk of lidocaine toxicity without liposuction at a dose of 28 mg/kg and with liposuction at a dose of 45 mg/kg was ≤1 per 2000. CONCLUSIONS: Preliminary estimates for maximum safe dosages of tumescent lidocaine are 28 mg/kg without liposuction and 45 mg/kg with liposuction. As a

  4. 21 CFR 520.1044 - Gentamicin sulfate oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Gentamicin sulfate oral dosage forms. 520.1044... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1044 Gentamicin sulfate oral dosage forms....

  5. 21 CFR 520.1120 - Haloxon oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Haloxon oral dosage forms. 520.1120 Section 520...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1120 Haloxon oral dosage forms....

  6. 21 CFR 520.1720 - Phenylbutazone oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Phenylbutazone oral dosage forms. 520.1720 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1720 Phenylbutazone oral dosage forms....

  7. 21 CFR 520.903 - Febantel oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Febantel oral dosage forms. 520.903 Section 520...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.903 Febantel oral dosage forms....

  8. 21 CFR 520.1448 - Monensin oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Monensin oral dosage forms. 520.1448 Section 520...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1448 Monensin oral dosage forms. Monensin, as the base or the sodium salt, contains a minimum of 90 percent...

  9. 21 CFR 520.1242 - Levamisole hydrochloride oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Levamisole hydrochloride oral dosage forms. 520... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1242 Levamisole hydrochloride oral dosage forms....

  10. 21 CFR 520.2520 - Trichlorfon oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Trichlorfon oral dosage forms. 520.2520 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2520 Trichlorfon oral dosage forms....

  11. 21 CFR 520.1450 - Morantel tartrate oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Morantel tartrate oral dosage forms. 520.1450... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1450 Morantel tartrate oral dosage forms....

  12. 21 CFR 520.2220 - Sulfadimethoxine oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sulfadimethoxine oral dosage forms. 520.2220... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2220 Sulfadimethoxine oral dosage forms....

  13. 21 CFR 520.2473 - Tioxidazole oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Tioxidazole oral dosage forms. 520.2473 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2473 Tioxidazole oral dosage forms....

  14. 21 CFR 520.2260 - Sulfamethazine oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sulfamethazine oral dosage forms. 520.2260 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2260 Sulfamethazine oral dosage forms....

  15. 21 CFR 520.2380 - Thiabendazole oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Thiabendazole oral dosage forms. 520.2380 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2380 Thiabendazole oral dosage forms....

  16. 21 CFR 520.2325 - Sulfaquinoxaline oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sulfaquinoxaline oral dosage forms. 520.2325... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2325 Sulfaquinoxaline oral dosage forms....

  17. 21 CFR 520.2123 - Spectinomycin oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Spectinomycin oral dosage forms. 520.2123 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2123 Spectinomycin oral dosage forms....

  18. 21 CFR 520.2345 - Tetracycline oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Tetracycline oral dosage forms. 520.2345 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2345 Tetracycline oral dosage forms....

  19. 21 CFR 520.2150 - Stanozolol oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Stanozolol oral dosage forms. 520.2150 Section 520...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2150 Stanozolol oral dosage forms....

  20. 21 CFR 520.2261 - Sulfamethazine sodium oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sulfamethazine sodium oral dosage forms. 520.2261 Section 520.2261 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2261 Sulfamethazine sodium oral dosage...

  1. 21 CFR 522.313 - Ceftiofur injectable dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ceftiofur injectable dosage forms. 522.313 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.313 Ceftiofur injectable dosage forms....

  2. 21 CFR 522.1660 - Oxytetracycline injectable dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Oxytetracycline injectable dosage forms. 522.1660... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1660 Oxytetracycline injectable dosage forms....

  3. 21 CFR 522.1660 - Oxytetracycline injectable dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Oxytetracycline injectable dosage forms. 522.1660... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1660 Oxytetracycline injectable dosage forms....

  4. 21 CFR 522.90 - Ampicillin injectable dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ampicillin injectable dosage forms. 522.90 Section...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.90 Ampicillin injectable dosage forms....

  5. 21 CFR 522.313 - Ceftiofur injectable dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ceftiofur injectable dosage forms. 522.313 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.313 Ceftiofur injectable dosage forms....

  6. 21 CFR 522.313 - Ceftiofur injectable dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ceftiofur injectable dosage forms. 522.313 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.313 Ceftiofur injectable dosage forms....

  7. 21 CFR 522.313 - Ceftiofur injectable dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ceftiofur injectable dosage forms. 522.313 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.313 Ceftiofur injectable dosage forms....

  8. 21 CFR 522.1660 - Oxytetracycline injectable dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Oxytetracycline injectable dosage forms. 522.1660... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1660 Oxytetracycline injectable dosage forms....

  9. 21 CFR 522.313 - Ceftiofur injectable dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ceftiofur injectable dosage forms. 522.313 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.313 Ceftiofur injectable dosage forms....

  10. 21 CFR 522.1222 - Ketamine hydrochloride injectable dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ketamine hydrochloride injectable dosage forms... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1222 Ketamine hydrochloride injectable dosage forms....

  11. 21 CFR 522.2444 - Thiopental injectable dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Thiopental injectable dosage forms. 522.2444... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.2444 Thiopental injectable dosage forms....

  12. 21 CFR 522.1222 - Ketamine hydrochloride injectable dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ketamine hydrochloride injectable dosage forms... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1222 Ketamine hydrochloride injectable dosage forms....

  13. 21 CFR 522.1660 - Oxytetracycline injectable dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxytetracycline injectable dosage forms. 522.1660... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1660 Oxytetracycline injectable dosage forms....

  14. 21 CFR 522.1222 - Ketamine hydrochloride injectable dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ketamine hydrochloride injectable dosage forms... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1222 Ketamine hydrochloride injectable dosage forms....

  15. 21 CFR 522.1660 - Oxytetracycline injectable dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Oxytetracycline injectable dosage forms. 522.1660... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1660 Oxytetracycline injectable dosage forms....

  16. 21 CFR 522.960 - Flumethasone injectable dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Flumethasone injectable dosage forms. 522.960... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.960 Flumethasone injectable dosage forms....

  17. 21 CFR 522.1222 - Ketamine hydrochloride injectable dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ketamine hydrochloride injectable dosage forms... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1222 Ketamine hydrochloride injectable dosage forms....

  18. Selective cesium removal from radioactive liquid waste by crown ether immobilized new class conjugate adsorbent.

    PubMed

    Awual, Md Rabiul; Yaita, Tsuyoshi; Taguchi, Tomitsugu; Shiwaku, Hideaki; Suzuki, Shinichi; Okamoto, Yoshihiro

    2014-08-15

    Conjugate materials can provide chemical functionality, enabling an assembly of the ligand complexation ability to metal ions that are important for applications, such as separation and removal devices. In this study, we developed ligand immobilized conjugate adsorbent for selective cesium (Cs) removal from wastewater. The adsorbent was synthesized by direct immobilization of dibenzo-24-crown-8 ether onto inorganic mesoporous silica. The effective parameters such as solution pH, contact time, initial Cs concentration and ionic strength of Na and K ion concentrations were evaluated and optimized systematically. This adsorbent was exhibited the high surface area-to-volume ratios and uniformly shaped pores in case cavities, and its active sites kept open functionality to taking up Cs. The obtained results revealed that adsorbent had higher selectivity toward Cs even in the presence of a high concentration of Na and K and this is probably due to the Cs-π interaction of the benzene ring. The proposed adsorbent was successfully applied for radioactive Cs removal to be used as the potential candidate in Fukushima nuclear wastewater treatment. The adsorbed Cs was eluted with suitable eluent and simultaneously regenerated into the initial form for the next removal operation after rinsing with water. The adsorbent retained functionality despite several cycles during sorption-elution-regeneration operations.

  19. Application of a novel magnetic carbon nanotube adsorbent for removal of mercury from aqueous solutions.

    PubMed

    Homayoon, Farshid; Faghihian, Hossein; Torki, Firoozeh

    2017-04-01

    In this research, multiwall carbon nanotube was magnetized and subsequently functionalized by thiosemicarbazide. After characterization by FTIR, BET, SEM, EDAX, and VSM techniques, the magnetized adsorbent (multi-walled carbon nanotubes (MWCNTs)/Fe3O4) was used for removal of Hg(2+) from aqueous solutions and the experimental conditions were optimized. The adsorption capacity of 172.83 mg g(-1) was obtained at 25 °C and pH = 3 which was superior to the value obtained for initial multiwall carbon nanotube, magnetized sample, and many previously reported values. In the presence of Pb(+2) and Cd(+2), the adsorbent was selective towards mercury when their concentration was respectively below 50 and 100 mg L(-1). The adsorption process was kinetically fast and the equilibration was attained within 60 min with 69.5% of the capacity obtained within 10 min. The used adsorbent was regenerated by HNO3 solution, and the regenerated adsorbent retained 92% of its initial capacity. The magnetic sensitivity of the adsorbent allowed the simple separation of the used adsorbent from the solution by implying an appropriate external magnetic field. The adsorption data was well fitted to the Langmuir isotherm model, indicating homogeneous and monolayer adsorption of mercury by the adsorbent.

  20. The uranium from seawater program at PNNL: Overview of marine testing, adsorbent characterization, adsorbent durability, adsorbent toxicity, and deployment studies

    DOE PAGES

    Gill, Gary A.; Kuo, Li -Jung; Janke, Christopher James; ...

    2016-02-07

    The Pacific Northwest National Laboratory's (PNNL) Marine Science Laboratory (MSL) located along the coast of Washington State is evaluating the performance of uranium adsorption materials being developed for seawater extraction under realistic marine conditions with natural seawater. Two types of exposure systems were employed in this program: flow-through columns for testing of fixed beds of individual fibers and pellets and a recirculating water flume for testing of braided adsorbent material. Testing consists of measurements of the adsorption of uranium and other elements from seawater as a function of time, typically 42 to 56 day exposures, to determine the adsorbent capacitymore » and adsorption rate (kinetics). Analysis of uranium and other trace elements collected by the adsorbents was conducted following strong acid digestion of the adsorbent with 50% aqua regia using either Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) or Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The ORNL 38H adsorbent had a 56 day adsorption capacity of 3.30 ± 0.68 g U/ kg adsorbent (normalized to a salinity of 35 psu), a saturation adsorption capacity of 4.89 ± 0.83 g U/kg of adsorbent material (normalized to a salinity of 35 psu) and a half-saturation time of 28 10 days. The AF1 adsorbent material had a 56 day adsorption capacity of 3.9 ± 0.2 g U/kg adsorbent material (normalized to a salinity of 35 psu), a saturation capacity of 5.4 ± 0.2 g U/kg adsorbent material (normalized to a salinity of 35 psu) and a half saturation time of 23 2 days. The ORNL amidoxime-based adsorbent materials are not specific for uranium, but also adsorb other elements from seawater. The major doubly charged cations in seawater (Ca and Mg) account for a majority of the cations adsorbed (61% by mass and 74% by molar percent). For the ORNL AF1 adsorbent material, U is the 4th most abundant element adsorbed by mass and 7th most abundant by molar percentage. Marine testing

  1. The uranium from seawater program at PNNL: Overview of marine testing, adsorbent characterization, adsorbent durability, adsorbent toxicity, and deployment studies

    SciTech Connect

    Gill, Gary A.; Kuo, Li -Jung; Janke, Christopher James; Park, Jiyeon; Jeters, Robert T.; Bonheyo, George T.; Pan, Horng -Bin; Wai, Chien; Khangaonkar, Tarang P.; Bianucci, Laura; Wood, Jordana R.; Warner, Marvin G.; Peterson, Sonja; Abrecht, David G.; Mayes, Richard T.; Tsouris, Costas; Oyola, Yatsandra; Strivens, Jonathan E.; Schlafer, Nicholas J.; Addleman, Shane R.; Chouyyok, Wilaiwan; Das, Sadananda; Kim, Jungseung; Buesseler, Ken; Breier, Crystal; D'Alessandro, Evan

    2016-02-07

    The Pacific Northwest National Laboratory's (PNNL) Marine Science Laboratory (MSL) located along the coast of Washington State is evaluating the performance of uranium adsorption materials being developed for seawater extraction under realistic marine conditions with natural seawater. Two types of exposure systems were employed in this program: flow-through columns for testing of fixed beds of individual fibers and pellets and a recirculating water flume for testing of braided adsorbent material. Testing consists of measurements of the adsorption of uranium and other elements from seawater as a function of time, typically 42 to 56 day exposures, to determine the adsorbent capacity and adsorption rate (kinetics). Analysis of uranium and other trace elements collected by the adsorbents was conducted following strong acid digestion of the adsorbent with 50% aqua regia using either Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) or Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The ORNL 38H adsorbent had a 56 day adsorption capacity of 3.30 ± 0.68 g U/ kg adsorbent (normalized to a salinity of 35 psu), a saturation adsorption capacity of 4.89 ± 0.83 g U/kg of adsorbent material (normalized to a salinity of 35 psu) and a half-saturation time of 28 10 days. The AF1 adsorbent material had a 56 day adsorption capacity of 3.9 ± 0.2 g U/kg adsorbent material (normalized to a salinity of 35 psu), a saturation capacity of 5.4 ± 0.2 g U/kg adsorbent material (normalized to a salinity of 35 psu) and a half saturation time of 23 2 days. The ORNL amidoxime-based adsorbent materials are not specific for uranium, but also adsorb other elements from seawater. The major doubly charged cations in seawater (Ca and Mg) account for a majority of the cations adsorbed (61% by mass and 74% by molar percent). For the ORNL AF1 adsorbent material, U is the 4th most abundant element adsorbed by mass and 7th most abundant by molar percentage. Marine testing at Woods

  2. Complete braided adsorbent for marine testing to demonstrate 3g-U/kg-adsorbent

    SciTech Connect

    Janke, Chris; Yatsandra, Oyola; Mayes, Richard; none,; Gill, Gary; Li-Jung, Kuo; Wood, Jordana; Sadananda, Das

    2014-04-30

    ORNL has manufactured four braided adsorbents that successfully demonstrated uranium adsorption capacities ranging from 3.0-3.6 g-U/kg-adsorbent in marine testing at PNNL. Four new braided and leno woven fabric adsorbents have also been prepared by ORNL and are currently undergoing marine testing at PNNL.

  3. Inverse photoemission of adsorbed xenon multilayers on Ru(001): Refutation of final-state screening effects

    NASA Astrophysics Data System (ADS)

    Wandelt, K.; Jacob, W.; Memmel, N.; Dose, V.

    1986-09-01

    In this Letter we describe photoemission and inverse photoemission spectra of adsorbed xenon multilayers on Ru(001). Electron energy-loss spectra of xenon adsorbed on gold by Demuth, Avouris, and Schmeisser are included in the discussion. The observed layer-dependent shifts of the inverse photoemission spectra closer to the Fermi level clearly invalidate image screening effects as being the dominant cause of these shifts but support a ``floating'' of the adsorbed Xe potential well as a whole with the surface potential in the initial state.

  4. Extraction of palladium from acidic solutions with the use of carbon adsorbents

    SciTech Connect

    O.N. Kononova; N.G. Goryaeva; N.B. Dostovalova; S.V. Kachin; A.G. Kholmogorov

    2007-08-15

    We studied the sorption of palladium(II) on LKAU-4, LKAU-7, and BAU carbon adsorbents from model hydrochloric acid solutions and the solutions of spent palladium-containing catalysts. It was found that sorbents based on charcoal (BAU) and anthracite (LKAU-4) were characterized by high sorption capacities for palladium. The kinetics of the saturation of carbon adsorbents with palladium(II) ions was studied, and it was found that more than 60% of the initial amount of Pd(II) was recovered in a 1-h contact of an adsorbent with a model solution. This value for the solutions of spent catalysts was higher than 35%.

  5. Adsorbate Diffusion on Transition Metal Nanoparticles

    DTIC Science & Technology

    2015-01-01

    systematically studied adsorption and diffusion of atomic and diatomic species (H, C, N, O, CO, and NO) on nanometer-sized Pt and Cu nanoparticles with...species and two diatomic molecules (H, C, N, O, CO, and NO) as adsorbates and study the adsorption and diffusion of these adsorbates across the edges

  6. REFLECTIONS ON QUALITY AND DOSAGE OF PRESCHOOL AND CHILDREN'S DEVELOPMENT.

    PubMed

    Votruba-Drzal, Elizabeth; Miller, Portia

    2016-06-01

    This ambitious monograph tackles several important questions related to children's preschool experiences that have relevance for program and policy initiatives at the state and federal levels. The authors' approach is rigorous: they conduct parallel analyses across eight large and diverse studies of preschool children in center care and use meta-analysis to summarize patterns across studies. The study finds nonlinear associations between preschool quality and gains in language and literacy skills, with larger associations in higher versus lower quality classrooms. Results also show that domain-specific measures of preschool quality were more strongly related to children's development than global quality measures. The "dosage" of preschool was likewise important: more years in Head Start predicted larger vocabulary and literacy gains, whereas more time spent on instruction predicted greater literacy and math skills growth. In this commentary, we situate these findings in the broader literature addressing links between preschool experiences and children's development and discuss key takeaways for research, practice, and policy.

  7. [Reexaminations of dosages in Shanghanlun: comparison of the dosages among decoctions, pills and powder formulations].

    PubMed

    Suzuki, Tatsuhiko; Endo, Jiro

    2011-01-01

    This paper reveals the dosages of decoctions in Shanghanlun in relation of pills and powder formulations, and obtains following results. At the first examination of the system of weight, while Taohongjing shows three kinds of system of weight; [(1)1liang is equivalent to 14 g. (2) 1liang = 7 g (3) 1liang = 1.4 g], he describes the necessity of the corrective system of weight among the decoctions, the pills and the powder formulations. After Song dynasty, Zhusanfa, which is the method of preparing the decoction by placing powder ingredients of prescriptions in water and simmer, have been mainly adopted. In the term of Zhusanfa, although the whole quantities of prescriptions are written with the ancient weight unit, the notation of the dosage is indicated by the current weight unit, Qian. In Shanghanlun, since the dosage form seems to have been changed from the pills or the powders into the decoction, some of decoctions contain impractical dose for decoction.

  8. Database of Novel and Emerging Adsorbent Materials

    National Institute of Standards and Technology Data Gateway

    SRD 205 NIST/ARPA-E Database of Novel and Emerging Adsorbent Materials (Web, free access)   The NIST/ARPA-E Database of Novel and Emerging Adsorbent Materials is a free, web-based catalog of adsorbent materials and measured adsorption properties of numerous materials obtained from article entries from the scientific literature. Search fields for the database include adsorbent material, adsorbate gas, experimental conditions (pressure, temperature), and bibliographic information (author, title, journal), and results from queries are provided as a list of articles matching the search parameters. The database also contains adsorption isotherms digitized from the cataloged articles, which can be compared visually online in the web application or exported for offline analysis.

  9. NOx adsorber and method of regenerating same

    DOEpatents

    Endicott, Dennis L.; Verkiel, Maarten; Driscoll, James J.

    2007-01-30

    New technologies, such as NOx adsorber catalytic converters, are being used to meet increasingly stringent regulations on undesirable emissions, including NOx emissions. NOx adsorbers must be periodically regenerated, which requires an increased fuel consumption. The present disclosure includes a method of regenerating a NOx adsorber within a NOx adsorber catalytic converter. At least one sensor positioned downstream from the NOx adsorber senses, in the downstream exhaust, at least one of NOx, nitrous oxide and ammonia concentrations a plurality of times during a regeneration phase. The sensor is in communication with an electronic control module that includes a regeneration monitoring algorithm operable to end the regeneration phase when a time rate of change of the at least one of NOx, nitrous oxide and ammonia concentrations is after an expected plateau region begins.

  10. Picosecond adsorbate dynamics at condensed phase interfaces

    SciTech Connect

    Scott, T.W.; Chang, Y.J.; Martorell, J.

    1993-12-31

    Picosecond surface second harmonic generation has been used to probe a variety of elementary adsorbate reactions at liquid-solid interfaces. Electron transfer reactions at semiconductor-liquid junctions, geminate recombination of photogenerated free radical pairs and the orientational dynamics of dipolar adsorbates have all been explored in varying degrees of detail. These kinetic studies have led to a detailed analysis of adsorbate detection on the surface of non-centrosymmetric substrates as well as the use of total internal reflection geometries for signal enhancement from optically absorbing liquids. Particular emphasis has been placed on the static and dynamic characterization of adsorbate orientational distribution functions and how these are determined from the torque exerted on adsorbates by the angular part of the molecule-surface interaction potential.

  11. Fluorescence dynamics of microsphere-adsorbed sunscreens

    NASA Astrophysics Data System (ADS)

    Krishnan, R.

    2005-03-01

    Sunscreens are generally oily substances which are prepared in organic solvents, emulsions or dispersions with micro- or nanoparticles. These molecules adsorb to and integrate into skin cells. In order to understand the photophysical properties of the sunscreen, we compare steady-state and time-resolved fluorescence in organic solvent of varying dielectric constant ɛ and adsorbed to polystyrene microspheres and dispersed in water. Steady-state fluorescence is highest and average fluorescence lifetime longest in toluene, the solvent of lowest ɛ. However, there is no uniform dependence on ɛ. Sunscreens PABA and padimate-O show complex emission spectra. Microsphere-adsorbed sunscreens exhibit highly non-exponential decay, illustrative of multiple environments of the adsorbed molecule. The heterogeneous fluorescence dynamics likely characterizes sunscreen adsorbed to cells.

  12. Nanovalved Adsorbents for CH4 Storage.

    PubMed

    Song, Zhuonan; Nambo, Apolo; Tate, Kirby L; Bao, Ainan; Zhu, Minqi; Jasinski, Jacek B; Zhou, Shaojun J; Meyer, Howard S; Carreon, Moises A; Li, Shiguang; Yu, Miao

    2016-05-11

    A novel concept of utilizing nanoporous coatings as effective nanovalves on microporous adsorbents was developed for high capacity natural gas storage at low storage pressure. The work reported here for the first time presents the concept of nanovalved adsorbents capable of sealing high pressure CH4 inside the adsorbents and storing it at low pressure. Traditional natural gas storage tanks are thick and heavy, which makes them expensive to manufacture and highly energy-consuming to carry around. Our design uses unique adsorbent pellets with nanoscale pores surrounded by a coating that functions as a valve to help manage the pressure of the gas and facilitate more efficient storage and transportation. We expect this new concept will result in a lighter, more affordable product with increased storage capacity. The nanovalved adsorbent concept demonstrated here can be potentially extended for the storage of other important gas molecules targeted for diverse relevant functional applications.

  13. Alcohol, aggression and assertiveness in men: dosage and expectancy effects.

    PubMed

    Kreutzer, J S; Schneider, H G; Myatt, C R

    1984-05-01

    The effect of alcohol on aggression and assertiveness was examined in 54 men college students. A 2 (high vs low dosage expectancy) x 3 (0.0, 0.5 and 1.0 ml of 95% alcohol per kg of body weight) design was used. There was an increase in self-reported aggression at the moderate dosage but an increase only in profanity at the high dosage. The expectancy manipulation also produced an increase in self-reported aggression. Actual dosage and dosage expectancy did not influence assertiveness.

  14. Adrenal Insufficiency under Standard Dosage of Glucocorticoid Replacement after Unilateral Adrenalectomy for Cushing's Syndrome

    PubMed Central

    Fujii, Kentaro; Kurihara, Isao; Hiratsuka, Ken; Sato, Seiji; Yokota, Kenichi; Kobayashi, Sakiko; Shibata, Hirotaka; Itoh, Hiroshi

    2016-01-01

    Glucocorticoid replacement is needed for patients after adrenal surgery for Cushing's syndrome; however, the adequate dosage is not easily determined. The patient was a 62-year-old woman who has had hypertension for 5 years and presented with heart failure due to hypertrophic cardiomyopathy. She consulted with us because of general fatigue, facial edema, and muscle weakness and was diagnosed with Cushing's syndrome. A laparoscopic left adrenalectomy was performed, standard dosage of postoperative replacement was administered, and she was discharged with 30 mg/day of hydrocortisone (cortisol). However, she suffered from loss of appetite and was transferred to an emergency unit with the symptoms of adrenal insufficiency on postoperative day 15. After initial hydrocortisone replacement with 200 mg/day, the dosage was gradually decreased during hospitalization; however, reduction of hydrocortisone dosage lower than 60 mg/day was difficult because of nausea and fatigue. Her circadian cortisol profile after hydrocortisone administration showed delayed and lowered peaks, which suggested that hydrocortisone absorption in the intestine was impaired. Therefore, complicated heart failure may have led to the adrenal insufficiency in the patient. In such cases, we should consider postoperative administration of more than the standard dosage of hydrocortisone to avoid adrenal insufficiency after surgery for Cushing's syndrome. PMID:27375907

  15. [Formulation strategies of intraoral dosage forms].

    PubMed

    Kállai, Nikolett; Sebestyén, Zita; Szabó, Barnabás; Simon, Viktória; Antal, István; Zelkó, Romána

    2012-01-01

    The active pharmaceutical ingredient can be administered by several different routes. Although the oral route (per os) has been one of the most convenient and widely accepted delivery system for most drugs, it has number of disadvantages like the very low pH of the stomach, the high enzymatic activity, and extensive first-pass metabolism. Difficulty in swallowing (dysphagia) is common among all age groups, especially in "problematic" subpopulations like children and the elderly. Several novel intraoral dosage forms (IODs) have recently become available to modulate the physicochemical and pharmacokinetic characteristics of drugs, while improving patient compliance. The present article summarizes and categorizes their formulation possibilities.

  16. Extra adsorption and adsorbate superlattice formation in metal-organic frameworks.

    PubMed

    Sung Cho, Hae; Deng, Hexiang; Miyasaka, Keiichi; Dong, Zhiyue; Cho, Minhyung; Neimark, Alexander V; Ku Kang, Jeung; Yaghi, Omar M; Terasaki, Osamu

    2015-11-26

    Metal-organic frameworks (MOFs) have a high internal surface area and widely tunable composition, which make them useful for applications involving adsorption, such as hydrogen, methane or carbon dioxide storage. The selectivity and uptake capacity of the adsorption process are determined by interactions involving the adsorbates and their porous host materials. But, although the interactions of adsorbate molecules with the internal MOF surface and also amongst themselves within individual pores have been extensively studied, adsorbate-adsorbate interactions across pore walls have not been explored. Here we show that local strain in the MOF, induced by pore filling, can give rise to collective and long-range adsorbate-adsorbate interactions and the formation of adsorbate superlattices that extend beyond an original MOF unit cell. Specifically, we use in situ small-angle X-ray scattering to track and map the distribution and ordering of adsorbate molecules in five members of the mesoporous MOF-74 series along entire adsorption-desorption isotherms. We find in all cases that the capillary condensation that fills the pores gives rise to the formation of 'extra adsorption domains'-that is, domains spanning several neighbouring pores, which have a higher adsorbate density than non-domain pores. In the case of one MOF, IRMOF-74-V-hex, these domains form a superlattice structure that is difficult to reconcile with the prevailing view of pore-filling as a stochastic process. The visualization of the adsorption process provided by our data, with clear evidence for initial adsorbate aggregation in distinct domains and ordering before an even distribution is finally reached, should help to improve our understanding of this process and may thereby improve our ability to exploit it practically.

  17. Extra adsorption and adsorbate superlattice formation in metal-organic frameworks

    NASA Astrophysics Data System (ADS)

    Sung Cho, Hae; Deng, Hexiang; Miyasaka, Keiichi; Dong, Zhiyue; Cho, Minhyung; Neimark, Alexander V.; Ku Kang, Jeung; Yaghi, Omar M.; Terasaki, Osamu

    2015-11-01

    Metal-organic frameworks (MOFs) have a high internal surface area and widely tunable composition, which make them useful for applications involving adsorption, such as hydrogen, methane or carbon dioxide storage. The selectivity and uptake capacity of the adsorption process are determined by interactions involving the adsorbates and their porous host materials. But, although the interactions of adsorbate molecules with the internal MOF surface and also amongst themselves within individual pores have been extensively studied, adsorbate-adsorbate interactions across pore walls have not been explored. Here we show that local strain in the MOF, induced by pore filling, can give rise to collective and long-range adsorbate-adsorbate interactions and the formation of adsorbate superlattices that extend beyond an original MOF unit cell. Specifically, we use in situ small-angle X-ray scattering to track and map the distribution and ordering of adsorbate molecules in five members of the mesoporous MOF-74 series along entire adsorption-desorption isotherms. We find in all cases that the capillary condensation that fills the pores gives rise to the formation of ‘extra adsorption domains’—that is, domains spanning several neighbouring pores, which have a higher adsorbate density than non-domain pores. In the case of one MOF, IRMOF-74-V-hex, these domains form a superlattice structure that is difficult to reconcile with the prevailing view of pore-filling as a stochastic process. The visualization of the adsorption process provided by our data, with clear evidence for initial adsorbate aggregation in distinct domains and ordering before an even distribution is finally reached, should help to improve our understanding of this process and may thereby improve our ability to exploit it practically.

  18. Inorganic chemically active adsorbents (ICAAs)

    SciTech Connect

    Ally, M.R.; Tavlarides, L.

    1997-10-01

    Oak Ridge National Laboratory (ORNL) researchers are developing a technology that combines metal chelation extraction technology and synthesis chemistry. They begin with a ceramic substrate such as alumina, titanium oxide or silica gel because they provide high surface area, high mechanical strength, and radiolytic stability. One preparation method involves silylation to hydrophobize the surface, followed by chemisorption of a suitable chelation agent using vapor deposition. Another route attaches newly designed chelating agents through covalent bonding by the use of coupling agents. These approaches provide stable and selective, inorganic chemically active adsorbents (ICAAs) tailored for removal of metals. The technology has the following advantages over ion exchange: (1) higher mechanical strength, (2) higher resistance to radiation fields, (3) higher selectivity for the desired metal ion, (4) no cation exchange, (5) reduced or no interference from accompanying anions, (6) faster kinetics, and (7) easy and selective regeneration. Target waste streams include metal-containing groundwater/process wastewater at ORNL`s Y-12 Plant (multiple metals), Savannah River Site (SRS), Rocky Flats (multiple metals), and Hanford; aqueous mixed wastes at Idaho National Engineering Laboratory (INEL); and scrubber water generated at SRS and INEL. Focus Areas that will benefit from this research include Mixed Waste, and Subsurface Contaminants.

  19. Studies of phase transitions in the aripiprazole solid dosage form.

    PubMed

    Łaszcz, Marta; Witkowska, Anna

    2016-01-05

    Studies of the phase transitions in an active substance contained in a solid dosage form are very complicated but essential, especially if an active substance is classified as a BCS Class IV drug. The purpose of this work was the development of sensitive methods for the detection of the phase transitions in the aripiprazole tablets containing initially its form III. Aripiprazole exhibits polymorphism and pseudopolymorphism. Powder diffraction, Raman spectroscopy and differential scanning calorimetry methods were developed for the detection of the polymorphic transition between forms III and I as well as the phase transition of form III into aripiprazole monohydrate in tablets. The study involved the initial 10 mg and 30 mg tablets, as well as those stored in Al/Al blisters, a triplex blister pack and HDPE bottles (with and without desiccant) under accelerated and long term conditions. The polymorphic transition was not observed in the initial and stored tablets but it was visible on the DSC curve of the Abilify(®) 10 mg reference tablets. The formation of the monohydrate was observed in the diffractograms and Raman spectra in the tablets stored under accelerated conditions. The monohydrate phase was not detected in the tablets stored in the Al/Al blisters under long term conditions. The results showed that the Al/Al blisters can be recommended as the packaging of the aripiprazole tablets containing form III.

  20. Heat transfer to the adsorbent in solar adsorption cooling device

    NASA Astrophysics Data System (ADS)

    Pilat, Peter; Patsch, Marek; Papucik, Stefan; Vantuch, Martin

    2014-08-01

    The article deals with design and construction of solar adsorption cooling device and with heat transfer problem in adsorber. The most important part of adsorption cooling system is adsorber/desorber containing adsorbent. Zeolith (adsorbent) type was chosen for its high adsorption capacity, like a coolant was used water. In adsorber/desorber occur, at heating of adsorbent, to heat transfer from heat change medium to the adsorbent. The time required for heating of adsorber filling is very important, because on it depend flexibility of cooling system. Zeolith has a large thermal resistance, therefore it had to be adapted the design and construction of adsorber. As the best shows the tube type of adsorber with double coat construction. By this construction is ensured thin layer of adsorbent and heating is quick in all volume of adsorbent. The process of heat transfer was experimentally measured, but for comparison simulated in ANSYS, too.

  1. Adsorbed natural gas storage with activated carbon

    SciTech Connect

    Sun, Jian; Brady, T.A.; Rood, M.J.

    1996-12-31

    Despite technical advances to reduce air pollution emissions, motor vehicles still account for 30 to 70% emissions of all urban air pollutants. The Clean Air Act Amendments of 1990 require 100 cities in the United States to reduce the amount of their smog within 5 to 15 years. Hence, auto emissions, the major cause of smog, must be reduced 30 to 60% by 1998. Natural gas con be combusted with less pollutant emissions. Adsorbed natural gas (ANG) uses adsorbents and operates with a low storage pressure which results in lower capital costs and maintenance. This paper describes the production of an activated carbon adsorbent produced from an Illinois coal for ANG.

  2. Adsorption of inorganic and organic ions to polycarbophil as a means of sustained-release dosage formulation.

    PubMed

    See, N A; Russell, J; Connors, K A; Bass, P

    1987-06-01

    The adsorption and desorption of drugs and inorganic ions to and from polycarbophil (PC), a polymer, were investigated to determine if PC would be a suitable carrier for sustained-release dosage formulations. Both in vitro and in vivo experiments with a polycarbophil-atropine sulfate complex demonstrated the gradual-release properties of this system. Adsorbed Cr3+ ions, like atropine, are released slowly. In contrast, 51CrO4(2-) ions are predominantly bound in an irreversible manner. A third group of drugs minimally adsorbed to PC under the conditions studied. We conclude that PC under both in vitro and in vivo conditions is able to bind certain ions and drugs and then release them over a period of time in a predictable and repeatable manner.

  3. Application of longan shell as non-conventional low-cost adsorbent for the removal of cationic dye from aqueous solution

    NASA Astrophysics Data System (ADS)

    Wang, Ya; Zhu, Lin; Jiang, Haitao; Hu, Fang; Shen, Xiangqian

    2016-04-01

    With simple physical treatment, adsorption potential of longan shell for the methylene blue (MB) from aqueous solution was studied as a low-cost material under the conditions of adsorbent dosage (1-6 g/L), initial solution pH (2-12), contact time (5-180 min), temperature (293, 313, 313 K) and initial dye concentration (100-500 mg/L). The SEM images and FTIR spectra of longan shell before and after dye adsorption were analyzed to understand the adsorption process of MB onto longan shell. The kinetic data and the equilibrium data were simulated by different kinetic and isotherm models, respectively. The results showed that the adsorption process was well described by the pseudo-second-order kinetic model, and the experimental equilibrium data were better fit to Langmuir equation than Freundlich equation with the maximum adsorption capacity of 141.04 mg/g. In addition, main activation parameters (Ea, ΔH#, ΔS# and ΔG#) and thermodynamic parameters (ΔG°, ΔH° and ΔS°) of the absorption process were also determined.

  4. Photoexcitation of adsorbates on metal surfaces: One-step or three-step

    SciTech Connect

    Petek, Hrvoje

    2012-09-07

    In this essay we discuss the light-matter interactions at molecule-covered metal surfaces that initiate surface photochemistry. The hot-electron mechanism for surface photochemistry, whereby the absorption of light by a metal surface creates an electron-hole pair, and the hot electron scatters through an unoccupied resonance of adsorbate to initiate nuclear dynamics leading to photochemistry, has become widely accepted. Yet, ultrafast spectroscopic measurements of molecule-surface electronic structure and photoexcitation dynamics provide scant support for the hot electron mechanism. Instead, in most cases the adsorbate resonances are excited through photoinduced substrate-to-adsorbate charge transfer. Based on recent studies of the role of coherence in adsorbate photoexcitation, as measured by the optical phase and momentum resolved two-photon photoemission measurements, we examine critically the hot electron mechanism, and propose an alternative description based on direct charge transfer of electrons from the substrate to adsorbate. The advantage of this more quantum mechanically rigorous description is that it informs how material properties of the substrate and adsorbate, as well as their interaction, influence the frequency dependent probability of photoexcitation and ultimately how light can be used to probe and control surface femtochemistry.

  5. PERVAPORATION USING ADSORBENT-FILLED MEMBRANES

    EPA Science Inventory

    Membranes containing selective fillers, such as zeolites and activated carbon, can improve the separation by pervaporation. Applications of adsorbent-filled membranes in pervaporation have been demonstrated by a number of studies. These applications include removal of organic co...

  6. Chitin Adsorbents for Toxic Metals: A Review

    PubMed Central

    Anastopoulos, Ioannis; Bhatnagar, Amit; Bikiaris, Dimitrios N.; Kyzas, George Z.

    2017-01-01

    Wastewater treatment is still a critical issue all over the world. Among examined methods for the decontamination of wastewaters, adsorption is a promising, cheap, environmentally friendly and efficient procedure. There are various types of adsorbents that have been used to remove different pollutants such as agricultural waste, compost, nanomaterials, algae, etc., Chitin (poly-β-(1,4)-N-acetyl-d-glucosamine) is the second most abundant natural biopolymer and it has attracted scientific attention as an inexpensive adsorbent for toxic metals. This review article provides information about the use of chitin as an adsorbent. A list of chitin adsorbents with maximum adsorption capacity and the best isotherm and kinetic fitting models are provided. Moreover, thermodynamic studies, regeneration studies, the mechanism of adsorption and the experimental conditions are also discussed in depth. PMID:28067848

  7. Monitoring by Control Technique - Activated Carbon Adsorber

    EPA Pesticide Factsheets

    Stationary source emissions monitoring is required to demonstrate that a source is meeting the requirements in Federal or state rules. This page is about Activated Carbon Adsorber control techniques used to reduce pollutant emissions.

  8. IR investigations of surfaces and adsorbates

    SciTech Connect

    Gwyn Williams

    2001-12-10

    Synchrotron infrared reflection-absorption measurements on single crystal metal surfaces with adsorbates have led to the determination of many key parameters related to the bonding vibrational modes and the dynamics of adsorbates. In particular, energy couplings between electrons and adsorbate motion have been shown to be a dominant mechanism on metal surfaces. Excellent agreement has been obtained with calculations for many of the observations, and the synergy between theory and experiment has led to a deeper understanding of the roles of electrons and phonons in determining the properties of interfaces and their roles in phenomena as diverse as friction, lubrication, catalysis and adhesion. Nonetheless, as the experiments are pushed harder, to describe such effects as co-adsorbed systems, disagreements continue to challenge the theory and our comprehension also is still evolving.

  9. Parallel pore and surface diffusion of levulinic acid in basic polymeric adsorbents.

    PubMed

    Liu, Baojian; Yang, Yiwen; Ren, Qilong

    2006-11-03

    The equilibrium and kinetics of levulinic acid (LA) adsorption on two basic polymeric adsorbents, 335 (highly porous gel) and D315 (macroreticular), were investigated. Experimental adsorption rates in batch stirred vessels under a variety of operating conditions were described successfully by the parallel pore and surface diffusion model taking into account external mass transfer and nonlinear Toth isotherm. The film-pore diffusion model was matched with the rate data and the resulting apparent pore diffusivities were strongly concentration-dependent and approached to a constant value for 335 adsorbent. Thus, the constant value was taken as the accurate pore diffusivity, while the pore diffusivity in D315 was estimated from the particle porosity. The surface diffusivities decreased with increasing initial bulk concentration for both adsorbents. The inverse concentration dependence was correlated reasonably well to the change of isosteric heat of adsorption as amount adsorbed.

  10. Adsorption of Pb(II) from aqueous solution by a poly-elemental mesoporous adsorbent

    NASA Astrophysics Data System (ADS)

    Wu, Xiu-Wen; Ma, Hong-Wen; Yang, Jing; Wang, Feng-Jiao; Li, Zhi-Hong

    2012-05-01

    A poly-elemental mesoporous adsorbent was hydrothermally prepared from microcline in an alkaline condition with cetyltrimethylammonium bromide as synthesis directing agent. The properties of the mesoporous adsorbent were determined by X-ray powder diffraction, high-resolution transmission electron microscope, N2 adsorption, and solid-state Magic Angle Spinning Nuclear Magnetic Resonance. The pore size distribution was detected by small angle X-ray scattering. The particles size was observed by Scanning electron microscope imagine. The chemical content of SiO2 in the mesoporous adsorbent was determined by spectrometry of the silicone molybdenum and sulfosalicylic acid complexes, and Al2O3 determined by complexometry with ethylene diamine tetraacetic acid in the presence of KF-Zn(Ac)2 tests. The adsorption properties of the mesoporous adsorbent to Pb(II) were studied, and three main factors, the adsorption time, solution pH, and initial concentration of Pb(II), were considered in the adsorption experiments.

  11. An efficient removal of methyl orange dye from aqueous solution by adsorption onto chitosan/MgO composite: A novel reusable adsorbent

    NASA Astrophysics Data System (ADS)

    Haldorai, Yuvaraj; Shim, Jae-Jin

    2014-02-01

    We report a novel multi-functional magnesium oxide (MgO) immobilized chitosan (CS) composite was prepared by chemical precipitation method. The CS-MgO composite was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy and zeta potential. The composite was applied as a novel adsorbent for removal of methyl orange model dye and the effect of adsorbent dosage, pH and contact time were studied. The adsorption kinetics followed a pseudo second order reaction. The adsorbent efficiency was unaltered even after five cycles of reuse. In addition, the composite exhibited a superior antibacterial efficacy of 93% within 24 h against Escherichia coli as measured by colony forming units. Based on the data of present investigation the composite being a biocompatible, eco-friendly and low-cost adsorbent with antibacterial activity could find potential applications in variety of fields and in particular environmental applications.

  12. X Chromosome and Autosome Dosage Responses in Drosophila melanogaster Heads.

    PubMed

    Chen, Zhen-Xia; Oliver, Brian

    2015-04-07

    X chromosome dosage compensation is required for male viability in Drosophila. Dosage compensation relative to autosomes is two-fold, but this is likely to be due to a combination of homeostatic gene-by-gene regulation and chromosome-wide regulation. We have baseline values for gene-by-gene dosage compensation on autosomes, but not for the X chromosome. Given the evolutionary history of sex chromosomes, these baseline values could differ. We used a series of deficiencies on the X and autosomes, along with mutations in the sex-determination gene transformer-2, to carefully measure the sex-independent X-chromosome response to gene dosage in adult heads by RNA sequencing. We observed modest and indistinguishable dosage compensation for both X chromosome and autosome genes, suggesting that the X chromosome is neither inherently more robust nor sensitive to dosage change.

  13. [Influence of biological activated carbon dosage on landfill leachate treatment].

    PubMed

    Cui, Yan-Rui; Guo, Yan; Wu, Qing

    2014-08-01

    Effects of biological activated carbon (BAC) dosage on COD removal in landfill leachate treatment were compared. The COD removal efficiency of reactors with 0, 100 and 300 g activated carbon dosage per litre activated sludge was 12.9%, 19.6% and 27.7%, respectively. The results indicated that BAC improved the refractory organic matter removal efficiency and there was a positive correlation between COD removal efficiency and BAC dosage. The output of carbon dioxide after 8h of aeration in reactors was 109, 193 and 306 mg corresponding to the activated carbon dosages mentioned above, which indicated the amount of biodegradation and BAC dosage also had a positive correlation. The combination of adsorption and bioregeneration of BAC resulted in the positive correlation betweem organic matter removal efficiency and BAC dosage, and bioregeneration was the root cause for the microbial decomposition of refractory organics.

  14. Bayer Electrofilter Fines as Potential Se(VI) Adsorbents

    NASA Astrophysics Data System (ADS)

    Ayala, Julia; Fernández, Begoña

    2015-11-01

    Removal of Se(VI) from an aqueous solution under different conditions was investigated using Bayer electrofilter fines (BEFs), a waste from alumina production, as an adsorbent. Adsorption selenate was studied using batch adsorption experiments as a function of pH (2-12), contact time (0.08-30 h), adsorbent concentration (4-80 g/L), initial selenium concentration (5-203 mg/L), and ionic strength (0-0.1 M NaCl). The results showed that adsorption was significantly affected by pH Se(VI) having the highest affinity for BEFs at pH 3. Sorption Se(VI) reached equilibrium in 4 h. Increasing ionic strength decreased selenate sorption. The adsorption of Se(VI) onto BEFs was found to fit the Langmuir isotherm. Maximum selenium uptake values were calculated as 2.3613 mg/g and 1.5608 mg/g when using adsorbent concentrations of 20 g/L and 40 g/L, respectively.

  15. Hydrophobic Porous Material Adsorbs Small Organic Molecules

    NASA Technical Reports Server (NTRS)

    Sharma, Pramod K.; Hickey, Gregory S.

    1994-01-01

    Composite molecular-sieve material has pore structure designed specifically for preferential adsorption of organic molecules for sizes ranging from 3 to 6 angstrom. Design based on principle that contaminant molecules become strongly bound to surface of adsorbent when size of contaminant molecules is nearly same as that of pores in adsorbent. Material used to remove small organic contaminant molecules from vacuum systems or from enclosed gaseous environments like closed-loop life-support systems.

  16. Regenerable activated bauxite adsorbent alkali monitor probe

    DOEpatents

    Lee, Sheldon H. D.

    1992-01-01

    A regenerable activated bauxite adsorber alkali monitor probe for field applications to provide reliable measurement of alkali-vapor concentration in combustion gas with special emphasis on pressurized fluidized-bed combustion (PFBC) off-gas. More particularly, the invention relates to the development of a easily regenerable bauxite adsorbent for use in a method to accurately determine the alkali-vapor content of PFBC exhaust gases.

  17. Regenerable activated bauxite adsorbent alkali monitor probe

    SciTech Connect

    Lee, S.H.D.

    1991-01-22

    This invention relates to a regenerable activated bauxite adsorber alkali monitor probe for field applications to provide reliable measurement of alkali-vapor 5 concentration in combustion gas with special emphasis on pressurized fluidized-bed combustion (PFBC) off-gas. More particularly, the invention relates to the development of a easily regenerable bauxite adsorbent for use in a method to accurately determine the alkali-vapor content of PFBC 10 exhaust gases.

  18. Regenerable activated bauxite adsorbent alkali monitor probe

    DOEpatents

    Lee, S.H.D.

    1992-12-22

    A regenerable activated bauxite adsorber alkali monitor probe for field applications to provide reliable measurement of alkali-vapor concentration in combustion gas with special emphasis on pressurized fluidized-bed combustion (PFBC) off-gas. More particularly, the invention relates to the development of a easily regenerable bauxite adsorbent for use in a method to accurately determine the alkali-vapor content of PFBC exhaust gases. 6 figs.

  19. Infrared Analysis Of Enzymes Adsorbed Onto Model Surfaces

    NASA Astrophysics Data System (ADS)

    Story, Gloria M.; Rauch, Deborah S.; Brode, Philip F.; Marcott, Curtis A.

    1989-12-01

    The adsorption of the enzymes, subtilisin BPN' and lysozyme, onto model surfaces was examined using attenuated total reflectance (ATR) infrared (IR) spectroscopy. Using a cylindrical internal reflection (CIRcle) cell with a Germanium (Ge) internal reflection element (IRE), model hydrophilic surfaces were made by plasma cleaning the IRE and model hydrophobic surfaces were made by precoating the IRE with a thin film of polystyrene. Gas chromatography (GC)-IR data collection software was used to monitor adsorption kinetics during the first five minutes after injection of the enzyme into the CIRcle cell. It was found that for both lysozyme and BPN', most of the enzyme that was going to adsorb onto the model surface did so within ten seconds after injection. Nearly an order-of-magnitude more BPN' adsorbed on the hydrophobic Ge surface than the hydrophilic one, while lysozyme adsorbed somewhat more strongly to the hydrophilic Ge surface. Overnight, the lysozyme layer continued to increase in thickness, while BPN' maintained its initial coverage. The appearance of carboxylate bands in some of the adsorbed BPN' spectra suggests the occurrence of peptide bond hydrolysis. A Au/Pd coating on the CIRcle cell o-rings had a significant effect on the adsorption of BPN'. (This coating was applied in an attempt to eliminate interfering Teflon absorption bands.) An apparent electrochemical reaction occurred, involving BPN', Ge, Au/Pd, and the salt solution used to stabilize BPN'. The result of this reaction was enhanced adsorption of the enzyme around the coated o-rings, etching of the Ge IRE at the o-ring site, and some autolysis of the enzyme. No such reaction was observed with lysozyme.

  20. Adsorption equilibrium and dynamics of gasoline vapors onto polymeric adsorbents.

    PubMed

    Jia, Lijuan; Yu, Weihua; Long, Chao; Li, Aimin

    2014-03-01

    The emission of gasoline vapors is becoming a significant environmental problem especially for the population-dense area and also results in a significant economic loss. In this study, adsorption equilibrium and dynamics of gasoline vapors onto macroporous and hypercrosslinked polymeric resins at 308 K were investigated and compared with commercial activated carbon (NucharWV-A 1100). The results showed that the equilibrium and breakthrough adsorption capacities of virgin macroporous and hypercrosslinked polymeric resins were lower than virgin-activated carbon. Compared with origin adsorbents, however, the breakthrough adsorption capacities of the regenerated activated carbon for gasoline vapors decreased by 58.5 % and 61.3 % when the initial concentration of gasoline vapors were 700 and 1,400 mg/L, while those of macroporous and hypercrosslinked resins decreased by 17.4 % and 17.5 %, and 46.5 % and 45.5 %, respectively. Due to the specific bimodal property in the region of micropore (0.5-2.0 nm) and meso-macropore (30-70 nm), the regenerated hypercrosslinked polymeric resin exhibited the comparable breakthrough adsorption capacities with the regenerated activated carbon at the initial concentration of 700 mg/L, and even higher when the initial concentration of gasoline vapors was 1,400 mg/L. In addition, 90 % of relative humidity had ignorable effect on the adsorption of gasoline vapors on hypercrosslinked polymeric resin. Taken together, it is expected that hypercrosslinked polymeric adsorbent would be a promising adsorbent for the removal of gasoline vapors from gas streams.

  1. Determining aminoglycoside dosage and blood levels using a programmable calculator.

    PubMed

    Ng, P K

    1980-02-01

    A programmable calculator procedure for the determination of dosage regimens and steady-state peak and trough levels of aminoglycoside antibiotics is described. The calculator is programmed based on a one-compartment open model and first-order elimination of aminoglycosides. A detailed description of the programs and user instructions are presented. The programs allow calculation of intermittent i.v. infusion dosage regimens and steady-state levels, and adjustment of dosage and dosing interval when measured plasma levels differ significantly from predicted levels. The calculator programs provide a rapid means of predicting and modifying dosage regimens and steady-state plasma levels for aminoglycoside antibiotics.

  2. Electrically heated particulate filter regeneration using hydrocarbon adsorbents

    DOEpatents

    Gonze, Eugene V [Pinckney, MI

    2011-02-01

    An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine. A grid of electrically resistive material selectively heats exhaust passing through the upstream end to initiate combustion of particulates within the PF. A hydrocarbon adsorbent coating applied to the PF releases hydrocarbons into the exhaust to increase a temperature of the combustion of the particulates within the PF.

  3. 3,5-Dichlorophenol Removal From Wastewater Using Alternative Adsorbents

    NASA Astrophysics Data System (ADS)

    Kobetičová, Hana; Lipovský, Marek; Wachter, Igor; Soldán, Maroš

    2015-06-01

    The main objective of this paper is to evaluate the efficiency of 3,5-dichlorophenol removal from wastewater by using alternative low cost adsorbents. Waste from the production and processing of metals (black nickel mud, red mud) and a biosorbent (Lemna minor) were used for this research. Initial concentration of the contaminant was 4 mmol L-1, the contact time of sorbent and waste water was 0 - 48 hrs and the temperature during experiment was 25 ± 0.2 °C. The results show that the highest removal efficiency of 3,5 - dichlorophenol (58.18 %) was reached by the red mud in 48 hours.

  4. Insight into the adsorption of PPCPs by porous adsorbents: Effect of the properties of adsorbents and adsorbates.

    PubMed

    Zhu, Zengyin; Xie, Jiawen; Zhang, Mancheng; Zhou, Qing; Liu, Fuqiang

    2016-07-01

    Adsorption is an efficient method for removal of pharmaceuticals and personal care products (PPCPs). Magnetic resins are efficient adsorbents for water treatment and exhibit potential for PPCP removal. In this study, the magnetic hypercrosslinked resin Q100 was used for adsorption of PPCPs. The adsorption behavior of this resin was compared with those of two activated carbons, namely, Norit and F400D. Norit exhibited the fastest adsorption kinetics, followed by Q100. Norit featured a honeycomb shape and long-range ordered pore channels, which facilitated the diffusion of PPCPs. Moreover, the large average pore size of Q100 reduced diffusion resistance. The adsorbed amounts of 11 PPCPs on the three adsorbents increased with increasing adsorbate hydrophobicity. For Q100, a significant linear correlation was observed between the adsorption performance for PPCPs and hydrophobicity (logD value) of adsorbates (R(2) = 0.8951); as such, PPCPs with high logD values (>1.69) could be efficiently removed. Compared with those of Norit and F400D, the adsorption performance of Q100 was less affected by humic acid because of the dominant hydrophobic interaction. Furthermore, Q100 showed improved regeneration performance, which renders it promising for PPCP removal in practical applications.

  5. Recovery of iron oxides from acid mine drainage and their application as adsorbent or catalyst.

    PubMed

    Flores, Rubia Gomes; Andersen, Silvia Layara Floriani; Maia, Leonardo Kenji Komay; José, Humberto Jorge; Moreira, Regina de Fatima Peralta Muniz

    2012-11-30

    Iron oxide particles recovered from acid mine drainage represent a potential low-cost feedstock to replace reagent-grade chemicals in the production of goethite, ferrihydrite or magnetite with relatively high purity. Also, the properties of iron oxides recovered from acid mine drainage mean that they can be exploited as catalysts and/or adsorbents to remove azo dyes from aqueous solutions. The main aim of this study was to recover iron oxides with relatively high purity from acid mine drainage to act as a catalyst in the oxidation of dye through a Fenton-like mechanism or as an adsorbent to remove dyes from an aqueous solution. Iron oxides (goethite) were recovered from acid mine drainage through a sequential precipitation method. Thermal treatment at temperatures higher than 300 °C produces hematite through a decrease in the BET area and an increase in the point of zero charge. In the absence of hydrogen peroxide, the solids adsorbed the textile dye Procion Red H-E7B according to the Langmuir model, and the maximum amount adsorbed decreased as the temperature of the thermal treatment increased. The decomposition kinetics of hydrogen peroxide is dependent on the H(2)O(2) concentration and iron oxides dosage, but the second-order rate constant normalized to the BET surface area is similar to that for different iron oxides tested in this and others studies. These results indicate that acid mine drainage could be used as a source material for the production of iron oxide catalysts/adsorbents, with comparable quality to those produced using analytical-grade reagents.

  6. Manganese-modified activated carbon fiber (Mn-ACF): Novel efficient adsorbent for Arsenic

    NASA Astrophysics Data System (ADS)

    Sun, Zhumei; Yu, Yichang; Pang, Shiyu; Du, Dongyun

    2013-11-01

    In this paper, a novel adsorbent, manganese-modified activated carbon fiber (Mn-ACF), was prepared and used for removal of As(V) from aqueous solution. The adsorbent was characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Adsorption of As(V) onto the as-prepared adsorbent from aqueous solutions was investigated and discussed. The adsorption kinetic data were modeled using the pseudo-first-order and pseudo-second order, respectively. The experimental results indicate that the pseudo-second-order kinetic equation can better describe the adsorption kinetics. Furthermore, adsorption equilibrium data of As(V) on the as-prepared adsorbent were analyzed by Langmuir and Freundlich models, which suggested that the Langmuir model provides a better correlation of the experimental data. The adsorption capacities (qmax) of As(V) on Mn-ACF at various temperatures, determined using the Langmuir equation, are 23.77, 33.23 and 36.53 mg g-1 at 303, 313 and 323 K, respectively. To the best of our knowledge, this adsorption capacity for As(V) is much larger than those reported in literatures (7.50-16.58 mg g-1). Notably, the qmax increases with increasing temperature, suggesting that adsorption of As(V) on Mn-ACF surface is an endothermic process, which is further confirmed by the calculated thermodynamic parameters including free energy, enthalpy, and entropy of adsorption process. The effect of experimental parameters such as pH and dosage of adsorbent on adsorption of As(V) were also studied. The present work will be useful in purification of groundwater.

  7. A nondestructive technique to determine the rate of oxygen permeation into solid dosage forms.

    PubMed

    Felton, L A; Timmins, G S

    2006-02-01

    The current study investigated the use of electron paramagnetic resonance (EPR) spectroscopy as a nondestructive method to quantify the partial pressure of oxygen (PO2) in tablets and hard shell capsules. Lithium phthalocyanine crystals (LiPC) were placed inside the dosage forms. The peak-to-peak linewidth of the first derivative of the LiPC EPR spectra was measured and, by calibration tables, the oxygen partial pressure, pO2, within the dosage form was determined. The intra-dosage form pO2 was followed as a function of time after changing the exterior gas stream composition. Results showed initial oxygen concentrations comparable to atmospheric levels in all tablets and capsules investigated. Oxygen rapidly permeated into unsealed gelatin and cellulosic hard shell capsules. Banding at the cap/body joint significantly reduced the oxygen permeation rate. Oxygen also rapidly permeated into tablet compacts, regardless of the compressional force used during tableting, while application of a polymeric film significantly decreased the rate of oxygen permeation. This EPR technique was shown to be a suitable nondestructive method to study oxygen permeation kinetics in solid dosage forms.

  8. Adherence and Dosage Contributions to Parenting Program Quality

    PubMed Central

    Gross, Thomas J.; Mason, W. Alex; Parra, Gilbert; Oats, Robert; Ringle, Jay; Haggerty, Kevin P.

    2015-01-01

    Objective The 3 most frequently examined elements of treatment fidelity are adherence, dosage, and quality. The relationships between these fidelity elements are complex, and additional research is needed to provide clarity. Improving clarity may be especially relevant to parenting programs, which tend to include direct explicit instruction (DEI) elements (i.e., instruction, modeling, and practice). The adherence to and dosage of these DEI elements are frequently assumed to improve program quality; however, little information is available to determine if such adherence and dosage affect program quality. This study examines whether adherence to and dosage of DEI elements predict quality ratings for a widely disseminated, manualized parenting program. Method Adherence is defined as the percentage of intervention tasks completed for each DEI element. Dosage is defined as the number of minutes and seconds spent in each intervention DEI element. Treatment fidelity is assessed for 36 of 144 sessions across 10 program facilitators. A hierarchical linear regression analysis examines the contributions of adherence and dosage in the prediction of session quality ratings. Results The analysis indicates that adherence accounts for a significant proportion of the variance (26%), whereas dosage contributes a nonsignificant proportion of variance (11%). Adherence to skill practice was the strongest individual predictor (β = .445, p < .01). Conclusions Findings suggest that ensuring a high degree of adherence can contribute to quality program delivery. However, more exploration is needed to better understand the ways in which adherence and dosage of DEI elements affect program quality. PMID:26726301

  9. 21 CFR 526.1696 - Penicillin intramammary dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin intramammary dosage forms. 526.1696 Section 526.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS INTRAMAMMARY DOSAGE FORMS § 526.1696...

  10. 21 CFR 526.1696 - Penicillin intramammary dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin intramammary dosage forms. 526.1696 Section 526.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Penicillin intramammary dosage forms....

  11. 21 CFR 520.1696 - Penicillin oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin oral dosage forms. 520.1696 Section 520.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696 Penicillin...

  12. 21 CFR 526.1696 - Penicillin intramammary dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin intramammary dosage forms. 526.1696 Section 526.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Penicillin intramammary dosage forms....

  13. 21 CFR 520.1696 - Penicillin oral dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin oral dosage forms. 520.1696 Section 520.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696 Penicillin...

  14. 21 CFR 526.1696 - Penicillin intramammary dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin intramammary dosage forms. 526.1696 Section 526.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Penicillin intramammary dosage forms....

  15. 21 CFR 520.1696 - Penicillin oral dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin oral dosage forms. 520.1696 Section 520.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696 Penicillin...

  16. 21 CFR 526.1696 - Penicillin intramammary dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin intramammary dosage forms. 526.1696 Section 526.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Penicillin intramammary dosage forms....

  17. 21 CFR 520.970 - Flunixin oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Flunixin oral dosage forms. 520.970 Section 520.970 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.970 Flunixin...

  18. 21 CFR 520.905 - Fenbendazole oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Fenbendazole oral dosage forms. 520.905 Section 520.905 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Fenbendazole oral dosage forms....

  19. 21 CFR 520.905 - Fenbendazole oral dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Fenbendazole oral dosage forms. 520.905 Section 520.905 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Fenbendazole oral dosage forms....

  20. 21 CFR 520.90 - Ampicillin oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ampicillin oral dosage forms. 520.90 Section 520.90 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.90 Ampicillin...

  1. 21 CFR 520.300 - Cambendazole oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Cambendazole oral dosage forms. 520.300 Section 520.300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS §...

  2. 21 CFR 520.88 - Amoxicillin oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Amoxicillin oral dosage forms. 520.88 Section 520.88 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.88 Amoxicillin...

  3. 21 CFR 520.82 - Aminopropazine fumarate oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Aminopropazine fumarate oral dosage forms. 520.82 Section 520.82 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS §...

  4. 21 CFR 520.154 - Bacitracin oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Bacitracin oral dosage forms. 520.154 Section 520.154 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.154 Bacitracin...

  5. 21 CFR 520.622 - Diethylcarbamazine citrate oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Diethylcarbamazine citrate oral dosage forms. 520.622 Section 520.622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS §...

  6. 21 CFR 520.620 - Diethylcarbamazine oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Diethylcarbamazine oral dosage forms. 520.620 Section 520.620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS §...

  7. 21 CFR 520.763 - Dithiazanine iodide oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Dithiazanine iodide oral dosage forms. 520.763 Section 520.763 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS §...

  8. 21 CFR 520.45 - Albendazole oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Albendazole oral dosage forms. 520.45 Section 520.45 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.45 Albendazole...

  9. 21 CFR 520.540 - Dexamethasone oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Dexamethasone oral dosage forms. 520.540 Section 520.540 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS §...

  10. 21 CFR 520.445 - Chlortetracycline oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Chlortetracycline oral dosage forms. 520.445 Section 520.445 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS §...

  11. 21 CFR 520.390 - Chloramphenicol oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Chloramphenicol oral dosage forms. 520.390 Section 520.390 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS §...

  12. 21 CFR 520.620 - Diethylcarbamazine oral dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Diethylcarbamazine oral dosage forms. 520.620 Section 520.620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Diethylcarbamazine oral dosage forms....

  13. 21 CFR 520.622 - Diethylcarbamazine citrate oral dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Diethylcarbamazine citrate oral dosage forms. 520.622 Section 520.622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Diethylcarbamazine citrate oral dosage forms....

  14. 21 CFR 520.2160 - Styrylpyridinium, diethylcarbamazine oral dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Styrylpyridinium, diethylcarbamazine oral dosage forms. 520.2160 Section 520.2160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.2160 Styrylpyridinium, diethylcarbamazine oral dosage forms....

  15. 21 CFR 520.2160 - Styrylpyridinium, diethylcarbamazine oral dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Styrylpyridinium, diethylcarbamazine oral dosage forms. 520.2160 Section 520.2160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.2160 Styrylpyridinium, diethylcarbamazine oral dosage forms....

  16. 21 CFR 520.620 - Diethylcarbamazine oral dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Diethylcarbamazine oral dosage forms. 520.620 Section 520.620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Diethylcarbamazine oral dosage forms....

  17. 21 CFR 520.622 - Diethylcarbamazine citrate oral dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Diethylcarbamazine citrate oral dosage forms. 520.622 Section 520.622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Diethylcarbamazine citrate oral dosage forms....

  18. 21 CFR 520.620 - Diethylcarbamazine oral dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Diethylcarbamazine oral dosage forms. 520.620 Section 520.620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Diethylcarbamazine oral dosage forms....

  19. 21 CFR 520.2160 - Styrylpyridinium, diethylcarbamazine oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Styrylpyridinium, diethylcarbamazine oral dosage forms. 520.2160 Section 520.2160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.2160 Styrylpyridinium, diethylcarbamazine oral dosage forms....

  20. 21 CFR 520.2160 - Styrylpyridinium, diethylcarbamazine oral dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Styrylpyridinium, diethylcarbamazine oral dosage forms. 520.2160 Section 520.2160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.2160 Styrylpyridinium, diethylcarbamazine oral dosage forms....

  1. 21 CFR 520.2160 - Styrylpyridinium, diethylcarbamazine oral dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Styrylpyridinium, diethylcarbamazine oral dosage forms. 520.2160 Section 520.2160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.2160 Styrylpyridinium, diethylcarbamazine oral dosage forms....

  2. 21 CFR 520.622 - Diethylcarbamazine citrate oral dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Diethylcarbamazine citrate oral dosage forms. 520.622 Section 520.622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Diethylcarbamazine citrate oral dosage forms....

  3. 21 CFR 520.622 - Diethylcarbamazine citrate oral dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Diethylcarbamazine citrate oral dosage forms. 520.622 Section 520.622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Diethylcarbamazine citrate oral dosage forms....

  4. 21 CFR 520.620 - Diethylcarbamazine oral dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Diethylcarbamazine oral dosage forms. 520.620 Section 520.620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Diethylcarbamazine oral dosage forms....

  5. Black Molecular Adsorber Coatings for Spaceflight Applications

    NASA Technical Reports Server (NTRS)

    Abraham, Nithin Susan; Hasegawa, Mark Makoto; Straka, Sharon A.

    2014-01-01

    The molecular adsorber coating is a new technology that was developed to mitigate the risk of on-orbit molecular contamination on spaceflight missions. The application of this coating would be ideal near highly sensitive, interior surfaces and instruments that are negatively impacted by outgassed molecules from materials, such as plastics, adhesives, lubricants, epoxies, and other similar compounds. This current, sprayable paint technology is comprised of inorganic white materials made from highly porous zeolite. In addition to good adhesion performance, thermal stability, and adsorptive capability, the molecular adsorber coating offers favorable thermal control characteristics. However, low reflectivity properties, which are typically offered by black thermal control coatings, are desired for some spaceflight applications. For example, black coatings are used on interior surfaces, in particular, on instrument baffles for optical stray light control. Similarly, they are also used within light paths between optical systems, such as telescopes, to absorb light. Recent efforts have been made to transform the white molecular adsorber coating into a black coating with similar adsorptive properties. This result is achieved by optimizing the current formulation with black pigments, while still maintaining its adsorption capability for outgassing control. Different binder to pigment ratios, coating thicknesses, and spray application techniques were explored to develop a black version of the molecular adsorber coating. During the development process, coating performance and adsorption characteristics were studied. The preliminary work performed on black molecular adsorber coatings thus far is very promising. Continued development and testing is necessary for its use on future contamination sensitive spaceflight missions.

  6. Size selective hydrophobic adsorbent for organic molecules

    NASA Technical Reports Server (NTRS)

    Sharma, Pramod K. (Inventor); Hickey, Gregory S. (Inventor)

    1997-01-01

    The present invention relates to an adsorbent formed by the pyrolysis of a hydrophobic silica with a pore size greater than 5 .ANG., such as SILICALITE.TM., with a molecular sieving polymer precursor such as polyfurfuryl alcohol, polyacrylonitrile, polyvinylidene chloride, phenol-formaldehyde resin, polyvinylidene difluoride and mixtures thereof. Polyfurfuryl alcohol is the most preferred. The adsorbent produced by the pyrolysis has a silicon to carbon mole ratio of between about 10:1 and 1:3, and preferably about 2:1 to 1:2, most preferably 1:1. The pyrolysis is performed as a ramped temperature program between about 100.degree. and 800.degree. C., and preferably between about 100.degree. and 600.degree. C. The present invention also relates to a method for selectively adsorbing organic molecules having a molecular size (mean molecular diameter) of between about 3 and 6 .ANG. comprising contacting a vapor containing the small organic molecules to be adsorbed with the adsorbent composition of the present invention.

  7. Membrane Perturbation Induced by Interfacially Adsorbed Peptides

    PubMed Central

    Zemel, Assaf; Ben-Shaul, Avinoam; May, Sylvio

    2004-01-01

    The structural and energetic characteristics of the interaction between interfacially adsorbed (partially inserted) α-helical, amphipathic peptides and the lipid bilayer substrate are studied using a molecular level theory of lipid chain packing in membranes. The peptides are modeled as “amphipathic cylinders” characterized by a well-defined polar angle. Assuming two-dimensional nematic order of the adsorbed peptides, the membrane perturbation free energy is evaluated using a cell-like model; the peptide axes are parallel to the membrane plane. The elastic and interfacial contributions to the perturbation free energy of the “peptide-dressed” membrane are evaluated as a function of: the peptide penetration depth into the bilayer's hydrophobic core, the membrane thickness, the polar angle, and the lipid/peptide ratio. The structural properties calculated include the shape and extent of the distorted (stretched and bent) lipid chains surrounding the adsorbed peptide, and their orientational (C-H) bond order parameter profiles. The changes in bond order parameters attendant upon peptide adsorption are in good agreement with magnetic resonance measurements. Also consistent with experiment, our model predicts that peptide adsorption results in membrane thinning. Our calculations reveal pronounced, membrane-mediated, attractive interactions between the adsorbed peptides, suggesting a possible mechanism for lateral aggregation of membrane-bound peptides. As a special case of interest, we have also investigated completely hydrophobic peptides, for which we find a strong energetic preference for the transmembrane (inserted) orientation over the horizontal (adsorbed) orientation. PMID:15189858

  8. Stability of dry coated solid dosage forms.

    PubMed

    Kablitz, Caroline Désirée; Urbanetz, Nora Anne

    2009-01-01

    The dry coating process was evaluated in terms of storage stability investigating drug release and agglomeration tendency of the different coated oral dosage forms; hydroxypropyl methylcellulose acetate succinate (HPMCAS) was used with triethylcitrate (TEC) as plasticizer and acetylated monoglyceride (Myvacet) as wetting agent. Talc or colloidal silicon dioxide (Aerosil) was used as anti-tacking agents. In contrast to coating formulations consisting of HPMCAS and Myvacet all formulations containing TEC showed enteric resistance and no agglomeration tendency after preparation. After storage at 10% RH +/- 5% enteric resistance is increased slightly. This increase is more pronounced at 60% RH +/- 5%. The formulations without anti-tacking agents showed higher drug releases after 12 and 24 months due to the damage of the film's integrity during sample preparation caused by the high tackiness of the film. Tackiness is not affected by storing if samples are stored at low relative humidity. At high relative humidity tackiness increases upon storage especially for formulations without anti-tacking agents. The sieving results of the agglomeration measurements after storage can be confirmed by ring shear measurements performed immediately after preparation and approved to be a tool, which is able to predict the agglomeration during storage.

  9. Foreign matter identification from solid dosage forms.

    PubMed

    Pajander, Jari; Haugshøj, Kenneth Brian; Bjørneboe, Kathrine; Wahlberg, Pia; Rantanen, Jukka

    2013-06-01

    Despite the increased request for robust quality systems, the end product may contain unidentified defects or discoloured regions. The foreign matter has to be monitored, identified and its source defined in order to prevent further contamination. However, the identification task can be complicated, since the origin and nature of foreign matter are various. The aim of this study is to provide an efficient foreign matter identification procedure for various substances possibly originating from pharmaceutical manufacturing environment. The surface or cross-section of the uncoated and coated tablets was analysed by utilization of different analytical techniques, such as light microscopy (LM), scanning electron microscopy in combination with energy dispersive X-ray microanalysis (SEM/EDX), Fourier transform infrared spectroscopy (FT-IR) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The results indicate that the combination of different analytical techniques proved to be a powerful approach in foreign matter identification. Light microscopy and SEM generate information on the morphology of foreign matter particles. EDX provides elemental analysis, which most often serves as final confirmation of the identification. However, FT-IR can be used to obtain information on the compounds chemical structure and conformation, and ToF-SIMS provides sensitivity in cases, where the entire solid dosage form is contaminated with foreign matter.

  10. Medication Dosage in Overweight and Obese Children

    PubMed Central

    Matson, Kelly L.; Horton, Evan R.; Capino, Amanda C.

    2017-01-01

    Approximately 31.8% of U.S. children ages 2 to 19 years are considered overweight or obese. This creates significant challenges to dosing medications that are primarily weight based (mg/kg) and in predicting pharmacokinetics parameters in pediatric patients. Obese individuals generally have a larger volume of distribution for lipophilic medications. Conversely, the Vd of hydrophilic medications may be increased or decreased due to increased lean body mass, blood volume, and decrease percentage of total body water. They may also experience decreased hepatic clearance secondary to fatty infiltrates of the liver. Hence, obesity may affect loading dose, dosage interval, plasma half-life, and time to reach steady-state concentration for various medications. Weight-based dosing is also a cause for potential medication errors. This position statement of the Pediatric Pharmacy Advocacy Group recommends that weight-based dosing should be used in patients ages < 18 years who are < 40 kg; weight-based dosing should be used in patients ≥ 40 kg, unless, unless the recommended adult dose for the specific indication is exceeded; clinicians should use pharmacokinetic analysis for adjusting medications in overweight/obese children; and research efforts continue to evaluate dosing of medications in obese/overweight children.

  11. Sulfur removal from fuel using zeolites/polyimide mixed matrix membrane adsorbents.

    PubMed

    Lin, Ligang; Wang, Andong; Dong, Meimei; Zhang, Yuzhong; He, Benqiao; Li, Hong

    2012-02-15

    A novel membrane adsorption process was proposed for the sulfur removal from fuels. The mixed matrix membranes (MMMs) adsorbents composed of polyimide (PI) and various Y zeolites were prepared. By the detailed characterization of FT-IR, morphology, thermal and mechanical properties of MMMs adsorbents, combining the adsorption and desorption behavior research, the process-structure-function relationship was discussed. Field-emission scanning electron microscope (FESEM) images show that the functional particles are incorporated into the three-dimensional network structure. MMMs adsorbents with 40% of zeolites content possess better physical properties, which was confirmed by mechanical strength and thermo stability analysis. Influence factors including post-treatment, content of incorporated zeolites, adsorption time, temperature, initial sulfur concentration as well as sulfur species on the adsorption performance of MMMs adsorbents have been evaluated. At 4 wt.% zeolites content, adsorption capacity for NaY/PI, AgY/PI and CeY/PI MMMs adsorbents come to 2.0, 7.5 and 7.9 mg S/g, respectively. And the regeneration results suggest that the corresponding spent membranes can recover about 98%, 90% and 70% of the desulfurization capacity, respectively. The distinct adsorption and desorption behavior of MMMs adsorbents with various functional zeolites was markedly related with their various binding force and binding mode with sulfur compounds.

  12. Low-cost magnetic adsorbent for As(III) removal from water: adsorption kinetics and isotherms.

    PubMed

    Kango, Sarita; Kumar, Rajesh

    2016-01-01

    Magnetite nanoparticles as adsorbent for arsenic (As) were coated on sand particles. The coated sand was used for the removal of highly toxic element 'As(III)' from drinking water. Here, batch experiments were performed with the variation of solution pH, adsorbent dose, contact time and initial arsenic concentration. The adsorbent showed significant removal efficiency around 99.6 % for As(III). Analysis of adsorption kinetics revealed that the adsorbent follows pseudo-second-order kinetics model showing R (2) = 0.999, whereas for pseudo-first-order kinetics model, the value of R (2) was 0.978. In the case of adsorption equilibrium, the data is well fitted with Langmuir adsorption isotherm model (R (2) > 0.99), indicating monolayer adsorption of As(III) on the surface of adsorbent. The existence of commonly present ions in water influences the removal efficiency of As(III) minutely in the following order PO4 (3-) > HCO3 (-) > Cl(-) > SO4 (2-). The obtained adsorbent can be used to overcome the problem of water filtration in rural areas. Moreover, as the nano-magnetite is coated on the sand, it avoids the problem of extraction of nanoparticles from treated water and can easily be removed by a simple filtration process.

  13. Adsorbent catalytic nanoparticles and methods of using the same

    DOEpatents

    Slowing, Igor Ivan; Kandel, Kapil

    2017-01-31

    The present invention provides an adsorbent catalytic nanoparticle including a mesoporous silica nanoparticle having at least one adsorbent functional group bound thereto. The adsorbent catalytic nanoparticle also includes at least one catalytic material. In various embodiments, the present invention provides methods of using and making the adsorbent catalytic nanoparticles. In some examples, the adsorbent catalytic nanoparticles can be used to selectively remove fatty acids from feedstocks for biodiesel, and to hydrotreat the separated fatty acids.

  14. Individualizing phenytoin dosage regimens using a programmable calculator.

    PubMed

    Ng, P K

    1980-04-01

    A programmable calculator procedure for the determination of individualized phenytoin dosage regimens is described. The calculator is programmed based on a one-compartment, open model using the Michaelis-Menten equation. A detailed description of the programs and user instructions are presented. The programs allow calculation of oral dosage regimens and steady-state phenytoin levels. The first two programs require a given dose and one corresponding steady-state minimum concentration point to estimate a dosage regimen and steady-state serum level. The second two programs, which provide a more accurate prediction of dosage regimen and steady-state serum levels, require two dose and steady-state minimum concentration poits. The calculator programs provide a rapid and reliable means of estimating a patient's phenytoin dosage regimens and steady-state serum levels.

  15. Guava (Psidium guajava) leaf powder: novel adsorbent for removal of methylene blue from aqueous solutions.

    PubMed

    Ponnusami, V; Vikram, S; Srivastava, S N

    2008-03-21

    Batch sorption experiments were carried out using a novel adsorbent, guava leaf powder (GLP), for the removal of methylene blue (MB) from aqueous solutions. Potential of GLP for adsorption of MB from aqueous solution was found to be excellent. Effects of process parameters pH, adsorbent dosage, concentration, particle size and temperature were studied. Temperature-concentration interaction effect on dye uptake was studied and a quadratic model was proposed to predict dye uptake in terms of concentration, time and temperature. The model conforms closely to the experimental data. The model was used to find optimum temperature and concentration that result in maximum dye uptake. Langmuir model represent the experimental data well. Maximum dye uptake was found to be 295mg/g, indicating that GLP can be used as an excellent low-cost adsorbent. Pseudo-first-order, pseudo-second order and intraparticle diffusion models were tested. From experimental data it was found that adsorption of MB onto GLP follow pseudo second order kinetics. External diffusion and intraparticle diffusion play roles in adsorption process. Free energy of adsorption (DeltaG degrees ), enthalpy change (DeltaH degrees ) and entropy change (DeltaS degrees ) were calculated to predict the nature of adsorption. Adsorption in packed bed was also evaluated.

  16. Aminosilica materials as adsorbents for the selective removal of aldehydes and ketones from simulated bio-oil.

    PubMed

    Drese, Jeffrey H; Talley, Anne D; Jones, Christopher W

    2011-03-21

    The fast pyrolysis of biomass is a potential route to the production of liquid biorenewable fuel sources. However, degradation of the bio-oil mixtures due to reaction of oxygenates, such as aldehydes and ketones, reduces the stability of the liquids and can impact long-term storage and shipping. Herein, solid aminosilica adsorbents are described for the selective adsorptive removal of reactive aldehyde and ketone species. Three aminosilica adsorbents are prepared through the reaction of amine-containing silanes with pore-expanded mesoporous silica. A fourth aminosilica adsorbent is prepared through the ring-opening polymerization of aziridine from pore-expanded mesoporous silica. Adsorption experiments with a representative mixture of bio-oil model compounds are presented using each adsorbent at room temperature and 45 °C. The adsorbent comprising only primary amines adsorbs the largest amount of aldehydes and ketones. The overall reactivity of this adsorbent increases with increasing temperature. Additional aldehyde screening experiments show that the reactivity of aldehydes with aminosilicas varies depending on their chemical functionality. Initial attempts to regenerate an aminosilica adsorbent by acid hydrolysis show that they can be at least partially regenerated for further use.

  17. The transit of dosage forms through the small intestine.

    PubMed

    Yuen, Kah-Hay

    2010-08-16

    The human small intestine, with its enormous absorptive surface area, is invariably the principal site of drug absorption. Hence, the residence time of a dosage form in this part of the gut can have a great influence on the absorption of the contained drug. Various methods have been employed to monitor the gastrointestinal transit of pharmaceutical dosage forms, but the use of gamma-scintigraphy has superceded all the other methods. However, careful consideration of the time interval for image acquisition and proper analysis of the scintigraphic data are important for obtaining reliable results. Most studies reported the mean small intestinal transit time of various dosage forms to be about 3-4h, being closely similar to that of food and water. The value does not appear to be influenced by their physical state nor the presence of food, but the timing of food intake following administration of the dosage forms can influence the small intestinal transit time. While the mean small intestinal transit time is quite consistent among dosage forms and studies, individual values can vary widely. There are differing opinions regarding the effect of density and size of dosage forms on their small intestinal transit properties. Some common excipients employed in pharmaceutical formulations can affect the small intestinal transit and drug absorption. There is currently a lack of studies regarding the effects of excipients, as well as the timing of food intake on the small intestinal transit of dosage forms and drug absorption.

  18. Photostability determination of commercially available nifedipine oral dosage formulations.

    PubMed

    Grundy, J S; Kherani, R; Foster, R T

    1994-12-01

    Nifedipine (NIF), a 1,4-dihydropyridine calcium channel antagonist, undergoes photodegradation to dehydronifedipine (DNIF) upon exposure to ultraviolet (UV) light and to the nitroso analogue of dehydronifedipine (NDNIF) when exposed to sunlight. NIF photodegradation products do not contribute to clinical activity, thus the content of NIF must remain uniform between equipotent formulations. Large differences in light stability between bioequivalent NIF products could potentially result in the therapeutic failure of unstable preparations. Consequently, if large photostability differences do exist between NIF preparations, product substitution may not be warranted. The light stability of 10 intact immediate- or controlled-release oral NIF formulations, obtained from several European and North American manufacturers, was studied using direct continuous artificial sunlight exposure extending over a 12-week period. The content of both NIF and NDNIF for each product was measured to determine the extent of photodecomposition using a specific and sensitive reversed-phase high pressure liquid chromatographic (HPLC) method. In addition, NIF photodegradation was measured using both pure NIF powder and methanolic NIF solution to determine the effectiveness of the artificial sunlight source used in this study. After 12 weeks of artificial sunlight exposure, less than 3% of NDNIF (w/w initial NIF content) was present in each of the 10 tested dosage forms. Photodegradation was greater than 10% (w/w initial NIF content) in approximately 5-10 min (mean t1/2 = 31 min), and in approximately 24 h (mean t1/2 = 7.7 days) of artificial sunlight exposure for methanolic NIF solution and pure NIF powder samples, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Form and function of dosage-compensated chromosomes--a chicken-and-egg relationship.

    PubMed

    Grimaud, Charlotte; Becker, Peter B

    2010-08-01

    Does the three-dimensional (3D) conformation of interphase chromosomes merely reflect their function or does it actively contribute to gene regulation? The analysis of sex chromosomes that are subject to chromosome-wide dosage compensation processes promises new insight into this question. Chromosome conformations are dynamic and largely determined by association of distant chromosomal loci in the nuclear space or by their anchoring to the nuclear envelope, effectively generating chromatin loops. The type and extent of such interactions depend on chromatin-bound transcription regulators and therefore reflects function. Dosage compensation adjusts the overall transcription activity of X chromosomes to assure balanced expression in the two sexes. Initial analyses of mammalian and Drosophila X chromosomes have led to the hypothesis that their conformations may not only reflect their functional state but may in turn contribute to the coordination of chromosome-wide tuning of transcription.

  20. Ochratoxin A removal from red wine by several oenological fining agents: bentonite, egg albumin, allergen-free adsorbents, chitin and chitosan.

    PubMed

    Quintela, S; Villarán, M C; López De Armentia, I; Elejalde, E

    2012-01-01

    The ability of several oenological fining agents to remove ochratoxin A (OTA) from red wine was studied. The adsorbents tested were activated sodium bentonite, egg albumin, allergen-free adsorbents (complex PVPP, plant protein and amorphous silica (complex) and high molecular weight gelatine), and the non-toxic biodegradable polymers (chitin and chitosan). Several dosages within the oenological use range were tested and the wine pH, colour parameters and polyphenol concentration impact associated with each fining agent were studied. Generally, OTA removal achieved in all treatments was higher when the adsorbent dosage increased, but the impact on wine quality also was higher. Chitin at 50 g hl(-1) removed 18% the OTA without affecting significantly the wine-quality parameters. At the highest dosage tested the gelatine and complex treatments achieved greater OTA removal (up to 39-40%) compared with bentonite, egg albumin and chitin. Moreover, the gelatine and the complex had a lower impact on colour parameters and polyphenol concentration compared with chitosan, whilst OTA was reduced to around 40%. Chitosan achieved the greatest OTA removal (67%), but it strongly affected the wine-quality parameters. Otherwise, bentonite showed a relative efficiency to remove OTA, but the CI value decreased considerably. The egg albumin treatment only removed OTA up to 16% and moreover affected strongly the CI value and CIELab parameters. The results of this survey showed that the non-toxic chitin adsorbent and the allergen-free adsorbents tested could be considered as alternative fining agents to reduce OTA in red wine.

  1. Development and testing of molecular adsorber coatings

    NASA Astrophysics Data System (ADS)

    Abraham, Nithin S.; Hasegawa, Mark M.; Straka, Sharon A.

    2012-10-01

    The effect of on-orbit molecular contamination has the potential to degrade the performance of spaceflight hardware and diminish the lifetime of the spacecraft. For example, sensitive surfaces, such as optical surfaces, electronics, detectors, and thermal control surfaces, are vulnerable to the damaging effects of contamination from outgassed materials. The current solution to protect these surfaces is through the use of zeolite coated ceramic adsorber pucks. However, these pucks and its additional complex mounting hardware requirements result in several disadvantages, such as size, weight, and cost related concerns, that impact the spacecraft design and the integration and test schedule. As a result, a new innovative molecular adsorber coating was developed as a sprayable alternative to mitigate the risk of on-orbit molecular contamination. In this study, the formulation for molecular adsorber coatings was optimized using various binders, pigment treatment methods, binder to pigment ratios, thicknesses, and spray application techniques. The formulas that passed coating adhesion and vacuum thermal cycling were further tested for its adsorptive capacity. Accelerated molecular capacitance tests were performed in an innovatively designed multi-unit system containing idealized contaminant sources. This novel system significantly increased the productivity of the testing phase for the various formulations that were developed. Work performed during the development and testing phases has demonstrated successful application of molecular adsorber coatings onto metallic substrates, as well as, very promising results for the adhesion performance and the molecular capacitance of the coating. Continued testing will assist in the qualification of molecular adsorber coatings for use on future contamination sensitive spaceflight missions.

  2. Development and Testing of Molecular Adsorber Coatings

    NASA Technical Reports Server (NTRS)

    Abraham, Nithin; Hasegawa, Mark; Straka, Sharon

    2012-01-01

    The effect of on-orbit molecular contamination has the potential to degrade the performance of spaceflight hardware and diminish the lifetime of the spacecraft. For example, sensitive surfaces, such as optical surfaces, electronics, detectors, and thermal control surfaces, are vulnerable to the damaging effects of contamination from outgassed materials. The current solution to protect these surfaces is through the use of zeolite coated ceramic adsorber pucks. However, these pucks and its additional complex mounting hardware requirements result in several disadvantages, such as size, weight, and cost related concerns, that impact the spacecraft design and the integration and test schedule. As a result, a new innovative molecular adsorber coating was developed as a sprayable alternative to mitigate the risk of on-orbit molecular contamination. In this study, the formulation for molecular adsorber coatings was optimized using various binders, pigment treatment methods, binder to pigment ratios, thicknesses, and spray application techniques. The formulations that passed coating adhesion and vacuum thermal cycling tests were further tested for its adsorptive capacity. Accelerated molecular capacitance tests were performed in an innovatively designed multi-unit system containing idealized contaminant sources. This novel system significantly increased the productivity of the testing phase for the various formulations that were developed. Work performed during the development and testing phases has demonstrated successful application of molecular adsorber coatings onto metallic substrates, as well as, very promising results for the adhesion performance and the molecular capacitance of the coating. Continued testing will assist in the qualification of molecular adsorber coatings for use on future contamination sensitive spaceflight missions.

  3. Development of high efficiency silica coated β-cyclodextrin polymeric adsorbent for the removal of emerging contaminants of concern from water.

    PubMed

    Bhattarai, Bikash; Muruganandham, M; Suri, Rominder P S

    2014-05-30

    This article reports the removal of several emerging contaminants (ECs) from water using novel adsorbent comprising of β-cyclodextrin (β-CD) coated on silica. Fourteen different adsorbents were synthesized under different experimental conditions using two different crosslinking agents (hexamethylene diisocyanate (HMDI) and epichlorohydrin (EPI)) and co-polymers (glycidoxypropyl trimethoxysilane (GPTS) and aminopropyl triethoxysilane (APTES). The adsorption capacities of the synthesized adsorbents were initially evaluated using 17β-estradiol, perfluorooctanoic acid (PFOA), and bisphenol-A (BPA) as adsorbates. The adsorbent prepared by using HMDI as crosslinking agent with DMSO as solvent was observed to perform the best, and removed more than 90% of 17β-estradiol, PFOA, and BPA. Furthermore, the β-CD loading on the ECs removal was studied which showed that the adsorbate removal increases with increase in loading of β-CD on the substrate. The best adsorbent was resynthesized in seven batches and its performance was reproducible for the removal of ten steroid hormones. The adsorbent showed very good regeneration potential for four successive adsorption-regeneration cycles to remove steroid hormones and PFOA. A plausible mechanism of adsorption is proposed. The synthesized best adsorbent is characterized using FTIR, HR-TEM, TGA and nitrogen adsorption analysis. The TGA results showed that the adsorbent has thermal stability of upto 300°C.

  4. Interaction between adsorbed hydrogen and potassium on a carbon nanocone containing material as studied by photoemission

    SciTech Connect

    Yu, Xiaofeng; Raaen, Steinar

    2015-09-14

    Hydrogen adsorption on a potassium doped carbon nanocone containing material was studied by photoelectron spectroscopy and work function measurement. The valence band spectra indicate that there is charge transfer from potassium to carbon. Upon deposition on carbon potassium is in its ionic state for lower doping and shows both ionic and metallic behavior at higher doping. Adsorption of hydrogen facilitates diffusion of potassium on the carbon material as seen by changes in the K{sub 2p} core level spectrum. Variations in the measured sample work function indicate that hydrogen initially adsorb on the K dopants and subsequently adsorb on the carbon cone containing material.

  5. Carboxymethyl cellulose-g-poly(2-(dimethylamino) ethyl methacrylate) hydrogel as adsorbent for dye removal.

    PubMed

    Salama, Ahmed; Shukry, Nadia; El-Sakhawy, Mohamed

    2015-02-01

    A novel adsorbent was prepared via crosslinking graft copolymerization of 2-(dimethylamino) ethyl methacrylate (DMAEMA) onto carboxymethyl cellulose (CMC) backbone. Ethylene glycol dimethacrylate and potassium persulphate were used as crosslinker and initiator, respectively. CMC-g-PDMAEMA hydrogel was used to remove methyl orange (MO) from aqueous solutions. The adsorption kinetics and isotherms were found to follow Pseudo-second-order kinetic model and Langmuir model, respectively. The high maximum adsorption capacity (1825 mg/g) implied that CMC-g-PDMAEMA can be used as promising adsorbent for the synthetic dyes removal from wastewater.

  6. Thiol-functionalized magnetite/graphene oxide hybrid as a reusable adsorbent for Hg2+ removal

    NASA Astrophysics Data System (ADS)

    Bao, Jian; Fu, You; Bao, Zhihao

    2013-11-01

    A thiol-functionalized magnetite/graphene oxide (MGO) hybrid as an adsorbent of Hg2+ was successfully synthesized by a two-step reaction. It exhibited a higher adsorption capacity compared to the bare graphene oxide and MGO due to the combined adsorption of thiol groups and magnetite nanocrystals. Its capacity reached 289.9 mg g-1 in a solution with an initial Hg2+ concentration of 100 mg l-1. After being exchanged with H+, the adsorbent could be reused. The adsorption of Hg2+ by the thiol-functionalized MGO fits well with the Freundlich isotherm model and followed pseudo-second-order kinetics.

  7. Systemic antibody response to nano-size calcium phospate biocompatible adjuvant adsorbed HEV-71 killed vaccine

    PubMed Central

    2015-01-01

    Purpose Since 1980s, human enterovirus-71 virus (HEV-71) is one of the common infectious disease in Asian Pacific region since late 1970s without effective commercial antiviral or protective vaccine is unavailable yet. The work examines the role of vaccine adjuvant particle size and the route of administration on postvaccination antibody response towards HEV-71 vaccine adsorbed to calcium phosphate (CaP) adjuvant. Materials and Methods First, CaP nano-particles were compared to a commercial micro-size and vaccine alone. Secondly, intradermal reduced dosage was compared to the conventional intramuscular immunization. Killed HEV-71 vaccines adsorbed to CaP nano-size (73 nm) and commercial one of micro-size (1.7 µm) were administered through intradermal, intramuscular, rabbits received vaccine alone and unvaccinated animals. Results CaP nano-particles adsorbed HEV-71 vaccine displayed higher antibody than the micro-size or unadsorbed vaccine alone, through both parenteral immunization routes. Moreover, the intradermal route (0.5 µg/mL) of 0.1-mL volume per vaccine dose induced equal IgG antibody level to 1.0-mL intramuscular route (0.5 µg/mL). Conclusion The intradermal vaccine adsorbed CaP nano-adjuvant showed safer and significant antibody response after one-tenth reduced dose quantity (0.5 µg/mL) of only 0.1-mL volume as the most suitable protective, cost effective and affordable formulation not only for HEV-71; but also for developing further effective vaccines toward other human pathogens. PMID:25649429

  8. Automatic identification and normalization of dosage forms in drug monographs

    PubMed Central

    2012-01-01

    Background Each day, millions of health consumers seek drug-related information on the Web. Despite some efforts in linking related resources, drug information is largely scattered in a wide variety of websites of different quality and credibility. Methods As a step toward providing users with integrated access to multiple trustworthy drug resources, we aim to develop a method capable of identifying drug's dosage form information in addition to drug name recognition. We developed rules and patterns for identifying dosage forms from different sections of full-text drug monographs, and subsequently normalized them to standardized RxNorm dosage forms. Results Our method represents a significant improvement compared with a baseline lookup approach, achieving overall macro-averaged Precision of 80%, Recall of 98%, and F-Measure of 85%. Conclusions We successfully developed an automatic approach for drug dosage form identification, which is critical for building links between different drug-related resources. PMID:22336431

  9. Buccal Dosage Forms: General Considerations for Pediatric Patients.

    PubMed

    Montero-Padilla, Soledad; Velaga, Sitaram; Morales, Javier O

    2017-02-01

    The development of an appropriate dosage form for pediatric patients needs to take into account several aspects, since adult drug biodistribution differs from that of pediatrics. In recent years, buccal administration has become an attractive route, having different dosage forms under development including tablets, lozenges, films, and solutions among others. Furthermore, the buccal epithelium can allow quick access to systemic circulation, which could be used for a rapid onset of action. For pediatric patients, dosage forms to be placed in the oral cavity have higher requirements for palatability to increase acceptance and therapy compliance. Therefore, an understanding of the excipients required and their functions and properties needs to be particularly addressed. This review is focused on the differences and requirements relevant to buccal administration for pediatric patients (compared to adults) and how novel dosage forms can be less invasive and more acceptable alternatives.

  10. Stability of oral liquid dosage forms of ethacrynic Acid.

    PubMed

    Ling, J; Gupta, V D

    2001-01-01

    The stability of ethacrynic acid (2.5 mg/mL) in oral liquid dosage forms was investigated. Tablets in 0.05 M phosphate buffer (available commercially) in water were used to prepare the dosage forms. The effects of mannitol and sugar on the stability of ethacrynic acid were negligible. There was no change in the physical appearance of the oral liquid dosage forms or pH values during the study. There was, however, a new peak in the chromatogram from the products(s) of decomposition. An oral liquid dosage form of ethacrynic acid containing 0.05 M phosphate buffer and 10% mannitol was stable for 24 days when stored at 5 deg C and for only 3 days when stored at 25 deg C.

  11. Dynamic analysis of a closed-cycle solar adsorption refrigerator using two adsorbent-adsorbate pairs

    SciTech Connect

    Hajji, A. ); Worek, W. ); Lavan, Z. )

    1991-05-01

    In this paper a dynamic analysis of a closed-cycle, solar adsorption refrigerator is presented. The instantaneous and daily system performance are studied using two adsorbent-adsorbate pairs, Zeolite 13X-Water and Chabazite-Methanol. The effect of design and operating parameters, including inert material thermal capacitance, matrix porosity, and evaporation and condenser temperatures on the solar and cycle coefficients of performance are evaluated.

  12. Influence of Polymers on the Crystal Growth Rate of Felodipine: Correlating Adsorbed Polymer Surface Coverage to Solution Crystal Growth Inhibition.

    PubMed

    Schram, Caitlin J; Taylor, Lynne S; Beaudoin, Stephen P

    2015-10-20

    The bioavailability of orally administered drugs that exhibit poor aqueous solubility can be enhanced with the use of supersaturating dosage forms. Stabilization of these forms by preventing or inhibiting crystallization in solution is an important area of study. Polymers can be used to stabilize supersaturated systems; however, the properties that impact their effectiveness as crystal growth rate inhibitors are not yet fully understood. In this study, the impact of various polymers on the crystal growth rate of felodipine and the conformation of these polymers adsorbed to crystalline felodipine was investigated in order to gain a mechanistic understanding of crystal growth inhibition. It was determined that polymer hydrophobicity impacted polymer adsorption as well as adsorbed polymer conformation. Polymer conformation impacts its surface coverage, which was shown to directly correlate to the polymer's effectiveness as a growth rate inhibitor. By modeling this correlation, it is possible to predict polymer effectiveness given the surface coverage of the polymer.

  13. Promotion of CO oxidation on PdO(101) by adsorbed H2O

    NASA Astrophysics Data System (ADS)

    Choi, Juhee; Pan, Li; Mehar, Vikram; Zhang, Feng; Asthagiri, Aravind; Weaver, Jason F.

    2016-08-01

    We investigated the influence of adsorbed H2O on the oxidation of CO on PdO(101) using temperature programmed reaction spectroscopy (TPRS), reflection absorption infrared spectroscopy (RAIRS) and density functional theory (DFT) calculations. We find that water inhibits CO adsorption on PdO(101) by site blocking, but also provides a more facile pathway for CO oxidation compared with the bare oxide surface. In the presence of adsorbed H2O, the oxidation of CO on PdO(101) produces a CO2 TPRS peak that is centered at a temperature 50 K lower than the main CO2 TPRS peak arising from CO oxidation on clean PdO(101) ( 330 vs. 380 K). RAIRS shows that CO continues to adsorb on atop-Pd sites of PdO(101) when H2O is co-adsorbed, and provides no evidence of other reactive intermediates. DFT calculations predict that the CO oxidation mechanism follows the same steps for CO adsorbed on PdO(101) with and without co-adsorbed H2O, wherein an atop-CO species recombines with an oxygen atom from the oxide surface lattice. According to DFT, hydrogen bonding interactions with adsorbed H2O species stabilize the carboxyl-like transition structure and intermediate that result from the initial recombination of CO and O on the PdO(101) surface. This stabilization lowers the energy barrier for CO oxidation on PdO(101) by 10 kJ/mol, in good agreement with our experimental estimate.

  14. Induced rupture of vesicles adsorbed on glass by pore formation at the surface-bilayer interface.

    PubMed

    Kataoka-Hamai, Chiho; Yamazaki, Tomohiko

    2015-02-03

    Supported lipid bilayers (SLBs) are often formed by spontaneous vesicle rupture and fusion on a solid surface. A well-characterized rupture mechanism for isolated vesicles is pore nucleation and expansion in the solution-exposed nonadsorbed area. In contrast, pore formation in the adsorbed bilayer region has not been investigated to date. In this work, we studied the detailed mechanisms of asymmetric rupture of giant unilamellar vesicles (GUVs) adsorbed on glass using fluorescence microscopy. Asymmetric rupture is the pathway where a rupture pore forms in a GUV near the edge of the glass-bilayer interface with high curvature and then expansion of the pore yields a planar bilayer patch. We show that asymmetric rupture occasionally resulted in SLB patches bearing a defect pore. The defect formation probability depended on lipid composition, salt concentration, and pH. Approximately 40% of negatively charged GUVs under physiological conditions formed pore-containing SLB patches, while negatively charged GUVs at low salt concentration or pH 4.0 and positively charged GUVs exhibited a low probability of defect inclusion. The edge of the defect pore was either in contact with (on-edge) or away from (off-edge) the edge of the planar bilayer. On-edge pores were predominantly formed over off-edge defects. Pores initially formed in the glass-adsorbed region before rupture, most frequently in close contact with the edge of the adsorbed region. When a pore formed near the edge of the adsorbed area or when the edge of a pore reached that of the adsorbed area by pore expansion, asymmetric rupture was induced from the defect site. These induced rupture mechanisms yielded SLB patches with an on-edge pore. In contrast, off-edge pores were produced when defect pore generation and subsequent vesicle rupture were uncoupled. The current results demonstrate that pore formation in the surface-adsorbed region of GUVs is not a negligible event.

  15. Fibrous adsorbent for removal of aqueous aromatic hydrocarbons.

    PubMed

    Jung, Yong-Jun; Kiso, Yoshiaki; Oguchi, Tatsuo; Yamada, Toshiro; Takagi, Hiroo; Nishimura, Kazuyuki

    2007-01-01

    Bundles of a strongly hydrophobic fibrous material (p-phenylene-2,6-benzobisoxazole; PBO; Zylon) were employed as an adsorbent for the removal of aqueous aromatic compounds, because the PBO fibers are too rigid to be woven and did not entrap suspended solids. The removal performance for nine kinds of polyaromatic hydrocarbons (PAHs) and di-(2-ethylhexyl) phthalate (DEHP) was evaluated. PAHs and DEHP at initial concentrations of 50 microg L(-1) were removed at 72.5-99.9% and ca. 95%, respectively, although the removal efficiencies were affected by the phase ratio (fiber weight/solution volume). The logarithm of the partition coefficient (log K) for planar PAHs was linearly correlated with the logarithm of the n-octanol/water partition coefficient (log P), but nonplanar PAHs, such as cis-stilbene, p-terphenyl, and o-terphenyl, showed significantly lower adsorption performance. The adsorbed PAHs were not desorbed effectively with CH3CN, CH2Cl2, and toluene. On the other hand, DEHP was effectively desorbed with methanol.

  16. Mechanisms of Sulfur Poisoning of NOx Adsorber Materials

    SciTech Connect

    Kim, Do Heui; Chin, Ya-Huei; Muntean, George G.; Peden, Charles HF; Stork, Kevin; Broering, L. C.; Stafford, R. J.; Stang, J. H.; Chen, H.-Y.; Cooper, B.; Hess, H.; Lafyatis, D.

    2004-10-01

    This annual report will review progress of the initial 4 months of a three-year effort between Cummins Engine Company and Pacific Northwest National Laboratory to understand and improve the performance and sulfur tolerance of the materials used in the NOx adsorber after-treatment technology in order to meet both performance and reliability standards required for diesel engines. The goal of this project is to enable NOx after-treatment technologies that will meet both EPA 2007 emission standards and customer cost, reliability and durability requirements. The project will consist of three phases. First, the efforts will focus on understanding the current limitation of capture, regeneration and durability of existing NOx adsorber materials, especially with respect to their sulfur tolerance. With this developing understanding, efforts will also be focused on the optimization of the NOx absorber chemical and material properties to increase performance and durability over many regeneration cycles. We anticipate that improved materials will be tested and evaluated, in partnership with Cummins, on diesel vehicle engines over expected operating conditions.

  17. Establishing Genetic Interactions by a Synthetic Dosage Lethality Phenotype

    PubMed Central

    Kroll, E. S.; Hyland, K. M.; Hieter, P.; Li, J. J.

    1996-01-01

    We have devised a genetic screen, termed synthetic dosage lethality, in which a cloned ``reference'' gene is inducibly overexpressed in a set of mutant strains carrying potential ``target'' mutations. To test the specificity of the method, two reference genes, CTF13, encoding a centromere binding protein, and ORC6, encoding a subunit of the origin of replication binding complex, were overexpressed in a large collection of mutants defective in either chromosome segregation or replication. CTF13 overexpression caused synthetic dosage lethality in combination with ctf14-42 (cbf2, ndc10), ctf17-61 (chl4), ctf19-58 and ctf19-26. ORC6 overexpression caused synthetic dosage lethality in combination with cdc2-1, cdc6-1, cdc14-1, cdc16-1 and cdc46-1. These relationships reflect specific interactions, as overexpression of CTF13 caused lethality in kinetochore mutants and overexpression of ORC6 caused lethality in replication mutants. In contrast, only one case of dosage suppression was observed. We suggest that synthetic dosage lethality identifies a broad spectrum of interacting mutations and is of general utility in detecting specific genetic interactions using a cloned wild-type gene as a starting point. Furthermore, synthetic dosage lethality is easily adapted to the study of cloned genes in other organisms. PMID:8722765

  18. Bioavailability of intranasal promethazine dosage forms in dogs

    NASA Technical Reports Server (NTRS)

    Ramanathan, R.; Geary, R. S.; Bourne, D. W.; Putcha, L.

    1998-01-01

    Intramuscular promethazine (PMZ) is used aboard the US Space Shuttle to ameliorate symptoms of space motion sickness. Bioavailability after an oral dose of PMZ during space flight is thought to be impaired because of gastrointestinal disturbances associated with weightlessness and space motion sickness. In an attempt to find an alternative dosage form for use in space, we evaluated two intranasal (i.n.) dosage forms of PMZ in dogs for absorption and bioavailability relative to that of an equivalent intramuscular dose. Promethazine (5 mg kg-1) was administered as two intranasal dosage forms and as an intramuscular (i.m.) dose to three dogs in a randomised cross-over design. Serial blood samples were taken and analysed for PMZ concentrations and the absorption and bioavailability of PMZ were calculated for the three dosage forms. PMZ absorption from the carboxymethyl cellulose microsphere i.n. dosage form was more rapid and complete than from the myverol cubic gel formulation or from an i.m. injection. Bioavailability of the microsphere formulation was also greater than that of the gel formulation (AUC 3009 vs 1727 ng h ml-1). The bioavailability of the two i.n. dosage forms (relative to that of the i.m. injection) were 94% (microsphere) and 54% (gel). The i.n. microsphere formulation of PMZ offers great promise as an effective non-invasive alternative for treating space motion sickness due to its rapid absorption and bioavailability equivalent to the i.m. dose.

  19. EMERGING TECHNOLOGY SUMMARY: DEMONSTRATION OF AMBERSORB 563 ADSORBENT TECHNOLOGY

    EPA Science Inventory

    A field pilot study was conducted to demonstrate the technical feasibility and cost-effectiveness of Ambersorb® 5631 carbonaceous adsorbent for remediating groundwater contaminated with volatile organic compounds (VOCs). The Ambersorb adsorbent technology demonstration consist...

  20. Quantitative analysis of Cu and Co adsorbed on fish bones via laser-induced breakdown spectroscopy

    NASA Astrophysics Data System (ADS)

    Rezk, R. A.; Galmed, A. H.; Abdelkreem, M.; Ghany, N. A. Abdel; Harith, M. A.

    2016-09-01

    In the present work, laser-induced breakdown spectroscopy (LIBS) has been applied for qualitative and quantitative analysis of heavy metals adsorbed by fish bones. Fish bones were used as a natural and low cost heavy metal sorbent (mainly Cu and Co) from synthetic wastewater. The removal efficiency of the adsorbent was studied as a function of initial metal concentration and pH value. Optimal experimental conditions were evaluated for improving the sensitivity of LIBS technique through parametric dependence studies. Furthermore, calibration curves were constructed based on X-ray fluorescence (XRF) analysis technique, whereas, the limits of detection (LOD) for Cu and Co were calculated. The results were validated by comparing LIBS data with those obtained by XRF spectrometry. The results of the two techniques are strongly correlated which verified the feasibility of using LIBS to detect traces of heavy metals adsorbed from wastewater by fish bones. This study reflects the potential of using LIBS in environmental applications.

  1. Utilization of granular activated carbon adsorber for nitrates removal from groundwater of the Cluj region.

    PubMed

    Moşneag, Silvia C; Popescu, Violeta; Dinescu, Adrian; Borodi, George

    2013-01-01

    The level of nitrates from groundwater from Cluj County and other areas from Romania have increased values, exceeding or getting close to the allowed limit values, putting in danger human and animal heath. In this study we used granular activated carbon adsorbent (GAC) for nitrate (NO(-)3) removal for the production of drinking water from groundwater of the Cluj county. The influences of the contact time, nitrate initial concentration, and adsorbent concentration have been studied. We determined the equilibrium adsorption capacity of GAC, used for NO(-)3 removal and we applied the Langmuir and Freundlich isotherm models. Ultraviolet-visible (UV-Vis) and Fourier transform infrared (FTIR) spectroscopy, X ray diffraction (XRD), Scanning Electron Microscopy (SEM) were used for process characterization. We also determined: pH, conductivity, Total Dissolved Solids and Total Hardness. The GAC adsorbents have excellent capacities of removing nitrate from groundwater from Cluj County areas.

  2. Optimization of operating parameters of novel composite adsorbent for organic pollutants removal from POME using response surface methodology.

    PubMed

    Adeleke, A O; Latiff, Ab Aziz Ab; Al-Gheethi, A A; Daud, Zawawi

    2017-05-01

    The present work aimed to develop a novel composite material made up of activated cow bone powder (CBP) as a starting material for reducing chemical oxygen demand (COD) and ammonia-nitrogen (NH3N) from palm oil mill effluent (POME). The optimization of the reduction efficiency was investigated using response surface methodology (RSM). Six independent variables used in the optimization experiments include pH (4-10), speed (0.27-9.66 rcf), contact time (2-24 h), particle size (1-4.35 mm), dilution factor (100-500) and adsorbent dosage (65-125 g/L). The chemical functional groups were determined using Fourier transform irradiation (FTIR). The elemental composition were detected using SEM-EDX, while thermal decomposition was investigated using thermo gravimetric analysis (TGA) in order to determine the effects of carbonization temperature on the adsorbent. The results revealed that the optimal reduction of COD and NH3N from raw POME was observed at pH 10, 50 rpm, within 2 h and 3 mm of particle size as well as at dilution factor of 500 and 125 g L(-1) of adsorbent dosage, the observed and predicted reduction were 89.60 vs. 85.01 and 75.61 vs. 74.04%, respectively for COD and NH3N. The main functional groups in the adsorbent were OH, NH, CO, CC, COC, COH, and CH. The SEM-EDX analysis revealed that the CBP-composite has a smooth surface with high contents of carbon. The activated CBP has very stable temperature profile with no significant weight loss (9.85%). In conclusion, the CBP-composite investigated here has characteristics high potential for the remediation of COD and NH3N from raw POME.

  3. Proper cyclin B3 dosage is important for precision of metaphase-to-anaphase onset timing in Caenorhabditis elegans.

    PubMed

    Tarailo-Graovac, Maja; Chen, Nansheng

    2012-08-01

    Cyclin-dependent kinases (CDK) and their compulsory cofactors, the cyclins, are the two key classes of regulatory molecules that determine the eukaryotic cell's progress through the cell cycle by substrate phosphorylation. Cdk1 forms complexes with B-type cyclins and phosphorylates a number of substrates as cells prepare to enter mitosis. CYB-3 (Cyclin B3) is a B-type cyclin that has been recently shown to be required for the timely metaphase-to-anaphase transition, presumably by alleviating a spindle assembly checkpoint (SAC) block. Previously, we have shown that doubling the CYB-3 dosage suppresses sterility in the absence of the essential SAC component MDF-1/Mad1. Here we demonstrate the importance of the Mos1-mediated single-copy insertion method for understanding the effects of gene dosage by generating strains that have more (two or three) copies of the cyb-3 in wild-type and mdf-1(gk2) backgrounds to investigate dosage effect of CYB-3 on mitotic progression as well as development and fertility in the absence and the presence of the MDF-1 checkpoint component. We show that tripling the dosage of CYB-3 results in a significantly variable metaphase-to-anaphase transition, both in wild-type and mdf-1(gk2) mutant backgrounds. Although a majority of embryos initiate anaphase onset normally, a significant number of embryos initiate anaphase with a delay. We also show that tripling the dosage of CYB-3 has no effect on viability in the wild-type background; however, it does reduce the sterility caused by the absence of MDF-1. Together, these data reveal that proper dosage of CYB-3 is important for precision of timely execution of anaphase onset regardless of the presence of the MDF-1 checkpoint component.

  4. Mammalian X chromosome inactivation evolved as a dosage-compensation mechanism for dosage-sensitive genes on the X chromosome.

    PubMed

    Pessia, Eugénie; Makino, Takashi; Bailly-Bechet, Marc; McLysaght, Aoife; Marais, Gabriel A B

    2012-04-03

    How and why female somatic X-chromosome inactivation (XCI) evolved in mammals remains poorly understood. It has been proposed that XCI is a dosage-compensation mechanism that evolved to equalize expression levels of X-linked genes in females (2X) and males (1X), with a prior twofold increase in expression of X-linked genes in both sexes ("Ohno's hypothesis"). Whereas the parity of X chromosome expression between the sexes has been clearly demonstrated, tests for the doubling of expression levels globally along the X chromosome have returned contradictory results. However, changes in gene dosage during sex-chromosome evolution are not expected to impact on all genes equally, and should have greater consequences for dosage-sensitive genes. We show that, for genes encoding components of large protein complexes (≥ 7 members)--a class of genes that is expected to be dosage-sensitive--expression of X-linked genes is similar to that of autosomal genes within the complex. These data support Ohno's hypothesis that XCI acts as a dosage-compensation mechanism, and allow us to refine Ohno's model of XCI evolution. We also explore the contribution of dosage-sensitive genes to X aneuploidy phenotypes in humans, such as Turner (X0) and Klinefelter (XXY) syndromes. X aneuploidy in humans is common and is known to have mild effects because most of the supernumerary X genes are inactivated and not affected by aneuploidy. Only genes escaping XCI experience dosage changes in X-aneuploidy patients. We combined data on dosage sensitivity and XCI to compute a list of candidate genes for X-aneuploidy syndromes.

  5. Analytical supercritical fluid extraction of adsorbent materials

    SciTech Connect

    Wright, B.W.; Wright, C.W.; Gale, R.W.; Smith, R.D.

    1987-01-01

    The use of supercritical fluids for the analytical extraction of semivolatile and higher molecular weight materials from various adsorbent and particulate matrices was investigated. Instrumentation was designed to allow gram quantities of the matrix to be extracted at pressures up to 400 bar and temperatures to 235 /sup 0/C with collection of the effluent in a sealed liquid-nitrogen-cooled flask. Carbon dioxide, isobutane, and methanol modified (20 mol %) carbon dioxide fluid systems were evaluated and compared to liquid Soxhlet extraction. Supercritical fluid extraction (SFE) provided very rapid (approx. =30 min) extraction with comparable efficiency to the Soxhlet methods, and both more rapid and more efficient extractions appear feasible. The more polar carbon dioxide-methanol fluid system gave higher extraction efficiencies for the more polar adsorbates and the isobutane system was more efficient for the higher molecular weight and less polar compounds.

  6. Efficient adsorbate transport on graphene by electromigration

    NASA Astrophysics Data System (ADS)

    Velizhanin, Kirill; Solenov, Dmitry

    2012-02-01

    Chemical functionalization of the surface of graphene holds promise for various applications ranging from nanoelectronics to surface catalysis and nano-assembling. In many practical situations it would be beneficial to be able to propel adsorbates along the graphene sheet in a controlled manner. We propose to use electromigration as an efficient means to transport adsorbates along the graphene surface. Within the tight-binding approximation for graphene, parametrized by density functional theory calculations, we estimate the contributions of the direct force and the electron wind force to the drift velocity of electromigration and demonstrate that the electromigration can be rather efficient. In particular, we show that the drift velocity of atomic oxygen covalently bound to graphene can reach up to 4 cm/s for realistic graphene samples. Further, we discuss ways to dynamically, i.e., during experiment, control the efficiency of electromigration by charging and/or local heating of graphene.

  7. Sand consolidation methods using adsorbable catalysts

    SciTech Connect

    Friedman, R. H.

    1985-04-23

    Methods are provided for selectively consolidating sand grains within a subterranean formation. First an acidic zirconium salt catalyst, such as ZrOCl/sub 2/, Zr(SO/sub 4/)/sub 2/, or ZrCl/sub 4/, is injected into the subterranean formation, wherein the acidic salt catalyst is adsorbed to the surface of the sand grains. Next a polymerizable resin composition such as furfuryl alcohol oligomer is introduced into the well formation. Polymerization of the resin occurs upon exposure to the elevated well temperatures and contact with the acid salt catalyst adsorbed to the sand grains. The polymerized resin serves to consolidate the surfaces of the sand grains while retaining permeability through the pore spaces. An ester of a weak organic acid is included with the resin compositions to control the extent of a polymerization by consuming the water by-product formed during the polymerization reaction.

  8. Gas storage using fullerene based adsorbents

    NASA Technical Reports Server (NTRS)

    Loutfy, Raouf O. (Inventor); Lu, Xiao-Chun (Inventor); Li, Weijiong (Inventor); Mikhael, Michael G. (Inventor)

    2000-01-01

    This invention is directed to the synthesis of high bulk density high gas absorption capacity adsorbents for gas storage applications. Specifically, this invention is concerned with novel gas absorbents with high gravimetric and volumetric gas adsorption capacities which are made from fullerene-based materials. By pressing fullerene powder into pellet form using a conventional press, then polymerizing it by subjecting the fullerene to high temperature and high inert gas pressure, the resulting fullerene-based materials have high bulk densities and high gas adsorption capacities. By pre-chemical modification or post-polymerization activation processes, the gas adsorption capacities of the fullerene-based adsorbents can be further enhanced. These materials are suitable for low pressure gas storage applications, such as oxygen storage for home oxygen therapy uses or on-board vehicle natural gas storage. They are also suitable for storing gases and vapors such as hydrogen, nitrogen, carbon dioxide, and water vapor.

  9. Analysis of Adsorbed Natural Gas Tank Technology

    NASA Astrophysics Data System (ADS)

    Knight, Ernest; Schultz, Conrad; Rash, Tyler; Dohnke, Elmar; Stalla, David; Gillespie, Andrew; Sweany, Mark; Seydel, Florian; Pfeifer, Peter

    With gasoline being an ever decreasing finite resource and with the desire to reduce humanity's carbon footprint, there has been an increasing focus on innovation of alternative fuel sources. Natural gas burns cleaner, is more abundant, and conforms to modern engines. However, storing compressed natural gas (CNG) requires large, heavy gas cylinders, which limits space and fuel efficiency. Adsorbed natural gas (ANG) technology allows for much greater fuel storage capacity and the ability to store the gas at a much lower pressure. Thus, ANG tanks are much more flexible in terms of their size, shape, and weight. Our ANG tank employs monolithic nanoporous activated carbon as its adsorbent material. Several different configurations of this Flat Panel Tank Assembly (FPTA) along with a Fuel Extraction System (FES) were examined to compare with the mass flow rate demands of an engine.

  10. Dosage Comparison of Snake Anti-Venomon Coagulopathy

    PubMed Central

    Rahmani, Ali Hassan; Jalali, Amir; Alemzadeh –Ansari, Mohammad Hassan; Tafazoli, Mina; Rahim, Fakher

    2014-01-01

    This study was done to determine whether high or low dose ofanti-snake venom (ASV) is better incoagulopathy invictims of envenoming by vipers. This retrospective study was conducted on the 154 patients (Mean age ± SD, Range) of viper snake bites who were referred to the emergency ward of Razi Hospital, Ahvaz, Iran over 2 years period (2004-2006).According to the treatment dosage the patients were divided in two groups include group 1(78 cases), low dose regimen and group 2 (76 cases), high dose one. In group 1, the treatment was performed by administration of 4 to 6 vials of ASV through intravenous infusion.In group 2, the patients were given 5 to 10 vials of ASV as an initial dose. In low dose regimen, the number of received packed red blood cell was higher (14 vs. 3) in comparison with high dose group. The number of ASV vials the patients received was 5.5and 21.06 in group 1 and 2, respectively (5.5±1.7 vs. 21.06±10.89; p < 0.01).The difference in frequency of coagulopathy complications, and need for using packed red blood cell were statistically significant(96.2% and 17.9% in group 1 vs. 34.2% and 3.9% in group 2, p < 0.01).It seems that cautious usage of high dose of ASV (10-20 vials) without very special concerns about the cost, dose, and without hazardous side effects is essential for the routine management of sever snake envenoming. PMID:24734082

  11. A benefit/risk approach towards selecting appropriate pharmaceutical dosage forms - an application for paediatric dosage form selection.

    PubMed

    Sam, Tom; Ernest, Terry B; Walsh, Jennifer; Williams, Julie L

    2012-10-05

    The design and selection of new pharmaceutical dosage forms involves the careful consideration and balancing of a quality target product profile against technical challenges and development feasibility. Paediatric dosage forms present particular complexity due to the diverse patient population, patient compliance challenges and safety considerations of this vulnerable population. This paper presents a structured framework for assessing the comparative benefits and risks of different pharmaceutical design options against pre-determined criteria relating to (1) efficacy, (2) safety and (3) patient access. This benefit/risk framework has then been applied to three hypothetical, but realistic, scenarios for paediatric dosage forms in order to explore its utility in guiding dosage form design and formulation selection. The approach allows a rigorous, systematic and qualitative assessment of the merits and disadvantages of each dosage form option and helps identify mitigating strategies to modify risk. The application of a weighting and scoring system to the criteria depending on the specific case could further refine the analysis and aid decision-making. In this paper, one case study is scored for illustrative purposes. However, it is acknowledged that in real development scenarios, the generation of actual data considering the very specific situation for the patient/product/developer would come into play to drive decisions on the most appropriate dosage form strategy.

  12. Remediation of AMD using industrial waste adsorbents

    NASA Astrophysics Data System (ADS)

    Mohammed, Nuur Hani Bte; Yaacob, Wan Zuhairi Wan

    2016-11-01

    The study investigates the characteristic of industrial waste as adsorbents and its potential as heavy metals absorbents in AMD samples. The AMD sample was collected from active mine pond and the pH was measured in situ. The metal contents were analyzed by ICP-MS. The AMD water was very acidic (pH< 3.5), and the average heavy metals content in AMD were high especially in Fe (822.029 mg/l). Fly ash was found to be the most effective absorbent material containing high percentage of CaO (57.24%) and SiO2 (13.88%), followed by ladle furnace slag containing of high amount of CaO (51.52%) and Al2O3 (21.23%), while biomass ash consists of SiO2 (43.07%) and CaO (12.97%). Tank analysis display a huge changes due to pH value change from acidity to nearly neutral phases. After 50 days, fly ash remediation successfully increase the AMD pH values from pH 2.57-7.09, while slag change from acidity to nearly alkaline phase from pH 2.60-7.3 and biomass has change to pH 2.54-6.8. Fly ash has successfully remove Fe, Mn, Cu, and Ni. Meanwhile, slag sample displays as an effective adsorbent to adsorb more Pb and Cd in acid mine drainage.

  13. The Drosophila over compensating males gene genetically inhibits dosage compensation in males.

    PubMed

    Lim, Chiat Koo; Kelley, Richard L

    2013-01-01

    Male Drosophila are monosomic for the X chromosome, but survive due to dosage compensation. They use the Male Specific Lethal (MSL) complex composed of noncoding roX RNA and histone modifying enzymes to hypertranscribe most genes along the X ∼1.6-1.8 fold relative to each female allele. It is not known how the MSL complex achieves this precise adjustment to a large and diverse set of target genes. We carried out a genetic screen searching for novel factors that regulate dosage compensation in flies. This strategy generated thirty alleles in a previously uncharacterized gene, over compensating males (ocm) that antagonizes some aspect of MSL activity. The mutations were initially recovered because they derepressed an MSL-dependent eye color reporter. Null ocm mutations are lethal to both sexes early in development revealing an essential function. Combinations of hypomorphic ocm alleles display a male specific lethality similar to mutations in the classic msl genes, but ocm males die due to excessive, rather than lack of dosage compensation. Males that die due to very low MSL activity can be partially rescued by ocm mutations. Likewise, males that would die from ocm mutations can be rescued by reducing the dose of various msl and roX genes. ocm encodes a large nuclear protein that shares a novel cysteine rich motif with known transcription factors.

  14. Computer-aided dosage in oral anticoagulation therapy using phenprocoumon. Problems and approaches.

    PubMed

    Cromme, L; Völler, H; Gäbler, F; Salzwedel, A; Taborski, U

    2010-11-01

    Oral anticoagulation using vitamin K antagonists has been established for over 50 years. Although it is highly effective in preventing thromboembolic incidents, its therapeutic control still remains problematic. Therefore, a computer-aided approach is recommended for deriving dosages. Up to now, the dosage is often based on the visual inspection of previous INR measurements, average weekly doses, and the INR target range. Statistical variations of measurement results and time-delayed effects of dosages, however, frequently result in the misinterpretation of data and suggest pseudo-trends. Treating physicians are not only responsible for determining the patient-specific maintenance dose, but must also respond to deviating INR values, overdosage or underdosage, initiate the oral anticoagulation therapy, and control the INR level in case of a new target range (bridging). Instructive examples are provided to illustrate the described difficulties. A computer-aided expert system is currently developed to ensure the therapeutic safety under the specified conditions. We present preliminary results from a study designed to validate mathematical models underlying such expert systems.

  15. Biowaiver monographs for immediate release solid oral dosage forms: ethambutol dihydrochloride.

    PubMed

    Becker, C; Dressman, J B; Amidon, G L; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Barends, D M

    2008-04-01

    Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing ethambutol dihydrochloride as the only active pharmaceutical ingredient (API) are reviewed. Ethambutol dihydrochloride is a Biopharmaceutics Classification System (BCS) Class III drug with permeability properties approaching the border between BCS Class I and III. BE problems of ethambutol formulations containing different excipients and different dosages forms have not been reported and hence the risk of bioinequivalence caused by excipients is low. Ethambutol has a narrow therapeutic index related to ocular toxicity. However, as long as the prescribers' information of the test product stipulates the need for regular monitoring of ocular toxicity, the additional patient risk is deemed acceptable. It is concluded that a biowaiver can be recommended for IR solid oral dosage forms provided that the test product (a) contains only excipients present in ethambutol IR solid oral drug products approved in ICH or associated countries, for instance as presented in this paper, (b) complies with the criteria for "very rapidly dissolving" and (c) has a prescribers' information indicating the need for testing the patient's vision prior to initiating ethambutol therapy and regularly during therapy.

  16. Negatively charged ions on Mg(0001) surfaces: appearance and origin of attractive adsorbate-adsorbate interactions.

    PubMed

    Cheng, Su-Ting; Todorova, Mira; Freysoldt, Christoph; Neugebauer, Jörg

    2014-09-26

    Adsorption of electronegative elements on a metal surface usually leads to an increase in the work function and decrease in the binding energy as the adsorbate coverage rises. Using density-functional theory calculations, we show that Cl adsorbed on a Mg(0001) surface complies with these expectations, but adsorption of {N,O,F} causes a decrease in the work function and an increase in the binding energy. Analyzing the electronic structure, we show that the presence of a highly polarizable electron spill-out in front of Mg(0001) causes this unusual adsorption behavior and is responsible for the appearance of a hitherto unknown net-attractive lateral electrostatic interaction between same charged adsorbates.

  17. Evolution of vertebrate sex chromosomes and dosage compensation.

    PubMed

    Graves, Jennifer A Marshall

    2016-01-01

    Differentiated sex chromosomes in mammals and other vertebrates evolved independently but in strikingly similar ways. Vertebrates with differentiated sex chromosomes share the problems of the unequal expression of the genes borne on sex chromosomes, both between the sexes and with respect to autosomes. Dosage compensation of genes on sex chromosomes is surprisingly variable - and can even be absent - in different vertebrate groups. Systems that compensate for different gene dosages include a wide range of global, regional and gene-by-gene processes that differ in their extent and their molecular mechanisms. However, many elements of these control systems are similar across distant phylogenetic divisions and show parallels to other gene silencing systems. These dosage systems cannot be identical by descent but were probably constructed from elements of ancient silencing mechanisms that are ubiquitous among vertebrates and shared throughout eukaryotes.

  18. The UDCA dosage deficit: a fate shared with CDCA.

    PubMed

    Roda, Enrico; Liva, Stefania; Ferrara, Francesco; Azzaroli, Francesco; Giovanelli, Silvia; Nigro, Giovanni; Festi, Davide; Mazzella, Giuseppe

    2002-03-01

    Ursodeoxycholic acid (UDCA) is used both as the treatment of choice in many cholestatic syndromes and as complementary therapy in many liver diseases. However, few dose-finding studies exist, and none has evaluated the efficacy and long-term safety of UDCA therapy in primary biliary cirrhosis (PBC). There is an open debate about UDCA's impact on the natural history of PBC, and no universal evidence of benefits on the major endpoint exists. This is perhaps due to a UDCA dosage deficit. Most clinical trials on PBC therapy have used conservative dosages of UDCA similar to those of chenodeoxycholic acid (CDCA) used for dissolution of gallstones. It may be necessary to re-evaluate the dosage of UDCA that provides the most effective treatment.

  19. The Uranium from Seawater Program at the Pacific Northwest National Laboratory: Overview of Marine Testing, Adsorbent Characterization, Adsorbent Durability, Adsorbent Toxicity, and Deployment Studies

    SciTech Connect

    Gill, Gary A.; Kuo, Li-Jung; Janke, Chris J.; Park, Jiyeon; Jeters, Robert T.; Bonheyo, George T.; Pan, Horng-Bin; Wai, Chien; Khangaonkar, Tarang; Bianucci, Laura; Wood, Jordana R.; Warner, Marvin G.; Peterson, Sonja; Abrecht, David G.; Mayes, Richard T.; Tsouris, Costas; Oyola, Yatsandra; Strivens, Jonathan E.; Schlafer, Nicholas J.; Addleman, R. Shane; Chouyyok, Wilaiwan; Das, Sadananda; Kim, Jungseung; Buesseler, Ken; Breier, Crystal; D’Alessandro, Evan

    2016-02-07

    The Pacific Northwest National Laboratory’s (PNNL) Marine Science Laboratory (MSL) located along the coast of Washington State is evaluating the performance of uranium adsorption materials being developed for seawater extraction under realistic marine conditions with natural seawater. Two types of exposure systems were employed in this program: flow-through columns for testing of fixed beds of individual fibers and pellets and a recirculating water flume for testing of braided adsorbent material. Testing consists of measurements of the adsorption of uranium and other elements from seawater as a function of time, typically 42 to 56 day exposures, to determine the adsorbent capacity and adsorption rate (kinetics). Analysis of uranium and other trace elements collected by the adsorbents was conducted following strong acid digestion of the adsorbent with 50% aqua regia using either Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) or Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The ORNL 38H adsorbent had a 56 day adsorption capacity of 3.30 ± 0.68 g U/ kg adsorbent (normalized to a salinity of 35 psu), a saturation adsorption capacity of 4.89 ± 0.83 g U/kg of adsorbent material (normalized to a salinity of 35 psu) and a half-saturation time of 28 ± 10 days. The AF1 adsorbent material had a 56 day adsorption capacity of 3.9 ± 0.2 g U/kg adsorbent material (normalized to a salinity of 35 psu), a saturation capacity of 5.4 ± 0.2 g U/kg adsorbent material (normalized to a salinity of 35 psu) and a half saturation time of 23 ± 2 days. The ORNL amidoxime-based adsorbent materials are not specific for uranium, but also adsorb other elements from seawater. The major doubly charged cations in seawater (Ca and Mg) account for a majority of the cations adsorbed (61% by mass and 74% by molar percent). For the ORNL AF1 adsorbent material, U is the 4th most abundant element adsorbed by mass and 7th most abundant by molar percentage

  20. Recovery of Technetium Adsorbed on Charcoal

    SciTech Connect

    Engelmann, Mark D.; Metz, Lori A.; Ballou, Nathan E.

    2006-05-01

    Two methods capable of near complete recovery of technetium adsorbed on charcoal are presented. The first involves liquid extraction of the technetium from the charcoal by hot 4M nitric acid. An average recovery of 98% (n=3) is obtained after three rounds of extraction. The second method involves dry ashing with air in a quartz combustion tube at 400-450 C. This method yields an average recovery of 96% (n=5). Other thermal methods were attempted, but resulted in reduced recovery and incomplete material balance

  1. Biowaiver monographs for immediate release solid oral dosage forms: prednisolone.

    PubMed

    Vogt, M; Derendorf, H; Krämer, J; Junginger, H E; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M

    2007-01-01

    Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing prednisolone are reviewed. Data on its solubility, oral absorption, and permeability are not totally conclusive, but strongly suggest a BCS Class 1 classification. Prednisolone's therapeutic indications and therapeutic index, pharmacokinetics, and the possibility of excipient interactions were also taken into consideration. Available evidence indicates that a biowaiver for IR solid oral dosage forms formulated with the excipients tabulated in this article would be unlikely to expose patients to undue risks.

  2. Storage stability of ketones on carbon adsorbents.

    PubMed

    Prado, C; Alcaraz, M J; Fuentes, A; Garrido, J; Periago, J F

    2006-09-29

    Activated coconut carbon constitutes the more widely used sorbent for preconcentration of volatile organic compounds in sampling workplace air. Water vapour is always present in the air and its adsorption on the activated carbon surface is a serious drawback, mainly when sampling polar organic compounds, such as ketones. In this case, the recovery of the compounds diminishes; moreover, ketones can be decomposed during storage. Synthetic carbons contain less inorganic impurities and have a lower capacity for water adsorption than coconut charcoal. The aim of this work was to evaluate the storage stability of various ketones (acetone, 2-butanone, 4-methyl-2-pentanone and cyclohexanone) on different activated carbons and to study the effect of adsorbed water vapour under different storage conditions. The effect of storage temperature on extraction efficiencies was significant for each ketone in all the studied sorbents. Recovery was higher when samples were stored at 4 degrees C. The results obtained for storage stability of the studied ketones showed that the performance of synthetic carbons was better than for the coconut charcoals. The water adsorption and the ash content of the carbons can be a measure of the reactive sites that may chemisorb ketones or catalize their decomposition. Anasorb 747 showed good ketone stability at least for 7 days, except for cyclohexanone. After 30-days storage, the stability of the studied ketones was excellent on Carboxen 564. This sorbent had a nearly negligible ash content and the adsorbed water was much lower than for the other sorbents tested.

  3. Optimizing heterosurface adsorbent synthesis for liquid chromatography

    NASA Astrophysics Data System (ADS)

    Bogoslovskii, S. Yu.; Serdan, A. A.

    2016-03-01

    The structural and geometric parameters of a silica matrix (SM) for the synthesis of heterosurface adsorbents (HAs) are optimized. Modification is performed by shielding the external surfaces of alkyl-modified silica (AS) using human serum albumin and its subsequent crosslinking. The structural and geometric characteristics of the SM, AS, and HA are measured via low-temperature nitrogen adsorption. It is found that the structural characteristics of AS pores with diameters D < 6 nm do not change during HA synthesis, while the volume of pores with diameters of 6 nm < D < 9 nm shrinks slightly due to the adsorption of albumin in the pore orifices. It is established that the volume of pores with diameters D > 9 nm reduces significantly due to adsorption of albumin. It is concluded that silica gel with a maximum pore size distribution close to 5 nm and a minimal proportion of pores with D > 9 nm is optimal for HA synthesis; this allows us to achieve the greatest similarity between the chromatographic retention parameters for HA and AS. The suitability of the synthesized adsorbents for analyzing drugs in biological fluids through direct sample injection is confirmed by chromatography. It was found that the percentage of the protein fraction detected at the outlet of the chromatographic column is 98%.

  4. Removal of uranium from aqueous solution by a low cost and high-efficient adsorbent

    NASA Astrophysics Data System (ADS)

    Liu, Yun-Hai; Wang, You-Qun; Zhang, Zhi-Bin; Cao, Xiao-Hong; Nie, Wen-Bin; Li, Qin; Hua, Rong

    2013-05-01

    In this study, a low-cost and high-efficient carbonaceous adsorbent (HTC-COOH) with carboxylic groups was developed for U(VI) removal from aqueous solution compared with the pristine hydrothermal carbon (HTC). The structure and chemical properties of resultant adsorbents were characterized by Scanning electron microscope (SEM), N2 adsorption-desorption, Fourier transform-infrared spectra (FT-IR) and acid-base titration. The key factors (solution pH, contact time, initial U(VI) concentrations and temperature) affected the adsorption of U(VI) on adsorbents were investigated using batch experiments. The adsorption of U(VI) on HTC and HTC-COOH was pH-dependent, and increased with temperature and initial ion concentration. The adsorption equilibrium of U(VI) on adsorbents was well defined by the Langmuir isothermal equation, and the monolayer adsorption capacity of HTC-COOH was found to be 205.8 mg/g. The kinetics of adsorption was very in accordance with the pseudo-second-order rate model. The adsorption processes of U(VI) on HTC and HTC-COOH were endothermic and spontaneous in nature according to the thermodynamics of adsorption. Furthermore, HTC-COOH could selectively adsorption of U(VI) in aqueous solution containing co-existing ions (Mg2+, Co2+, Ni2+, Zn2+ and Mn2+). From the results of the experiments, it is found that the HTC-COOH is a potential adsorbent for effective removal of U(VI) from polluted water.

  5. Narrative Language Intervention Intensity and Dosage: Telling the Whole Story

    ERIC Educational Resources Information Center

    Hoffman, LaVae M.

    2009-01-01

    This article expands on the work of S. F. Warren, M. E. Fey, and P. J. Yoder (2007) by applying their suggested intervention-intensity parameters to narrative language intervention with school-aged children. These pharmacologically based dosage concepts are examined from two perspectives: oral narrative skills as the target of language therapy and…

  6. Calculating Dosages: A Programed Learner for Student Nurses.

    ERIC Educational Resources Information Center

    Hare, Mary

    Intended for nursing students, this programed workbook contains learning exercises and study tests on using household, apothecary, and metric systems in calculating medication dosages. The material, organized in six learning units, was designed to help students meet six objectives: correctly interpret and use accepted symbols and abbreviations in…

  7. 77 FR 15961 - Oral Dosage Form New Animal Drugs; Phenylpropanolamine

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-19

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Phenylpropanolamine AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is amending the animal drug regulations to reflect approval of an original new animal...

  8. 77 FR 3927 - Oral Dosage Form New Animal Drugs; Deracoxib

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-26

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Deracoxib AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is amending the animal drug regulations to reflect approval of a supplemental new animal...

  9. Software for Dosage Individualization of Voriconazole for Immunocompromised Patients

    PubMed Central

    VanGuilder, Michael; Donnelly, J. Peter; Blijlevens, Nicole M. A.; Brüggemann, Roger J. M.; Jelliffe, Roger W.; Neely, Michael N.

    2013-01-01

    The efficacy of voriconazole is potentially compromised by considerable pharmacokinetic variability. There are increasing insights into voriconazole concentrations that are safe and effective for treatment of invasive fungal infections. Therapeutic drug monitoring is increasingly advocated. Software to aid in the individualization of dosing would be an extremely useful clinical tool. We developed software to enable the individualization of voriconazole dosing to attain predefined serum concentration targets. The process of individualized voriconazole therapy was based on concepts of Bayesian stochastic adaptive control. Multiple-model dosage design with feedback control was used to calculate dosages that achieved desired concentration targets with maximum precision. The performance of the software program was assessed using the data from 10 recipients of an allogeneic hematopoietic stem cell transplant (HSCT) receiving intravenous (i.v.) voriconazole. The program was able to model the plasma concentrations with a high level of precision, despite the wide range of concentration trajectories and interindividual pharmacokinetic variability. The voriconazole concentrations predicted after the last dosages were largely concordant with those actually measured. Simulations provided an illustration of the way in which the software can be used to adjust dosages of patients falling outside desired concentration targets. This software appears to be an extremely useful tool to further optimize voriconazole therapy and aid in therapeutic drug monitoring. Further prospective studies are now required to define the utility of the controller in daily clinical practice. PMID:23380734

  10. 21 CFR 201.55 - Statement of dosage.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Statement of dosage. 201.55 Section 201.55 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL LABELING Labeling Requirements for Prescription Drugs and/or Insulin § 201.55 Statement of...

  11. Health Instruction Packages: Drug Dosage, Classification, and Mixing.

    ERIC Educational Resources Information Center

    Bracchi, Dorothy P.; And Others

    Text, illustrations, and exercises are utilized in a set of seven learning modules to instruct nursing students in the fundamentals of drug classification, dosage, and mixing. The first module, by Dorothy Bracchi, teaches the student to identify six classifications of medication often administered to orthopedic patients: anti-neurospasmolytic…

  12. Recent progress and open questions in Drosophila dosage compensation

    PubMed Central

    Vensko, Steven P; Stone, Eric A

    2015-01-01

    Sexual dimorphism is observed in many traits across diverse taxa, and often it is quite extreme. Within a species, individuals of opposing sex can appear strikingly different, reflecting differences at the molecular level that may be similarly striking. Among the most extreme cases of such molecular sexual dimorphism is the quantity of sex chromosomes that each sex possesses. Hemizygous sex chromosomes are common to many species, and various mechanisms have evolved to regulate transcriptional activity to ensure appropriate sex chromosome-to-autosome gene expression stoichiometry. Among the most thoroughly investigated of these mechanisms is Drosophila melanogaster's male-specific lethal (MSL) complex-mediated dosage compensation. In Drosophila, the male X chromosome transcription is upregulated approximately two-fold in somatic tissues to counterbalance the effects of sex chromosome hemizygosity on transcript abundance. Despite dramatic advances in our understanding of the Drosophila dosage compensation, many questions remain unanswered, and our understanding of its molecular underpinnings remains incomplete. In this review, we synthesize recent progress in the field as a means to highlight open questions, including how the MSL complex targets the X chromosome, how dosage compensation has shaped evolution of X-linked genes, and the degree to which MSL complex-mediated dosage compensation varies in activity across somatic tissues. PMID:26213294

  13. 76 FR 78149 - Oral Dosage Form New Animal Drugs; Estriol

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-16

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Estriol AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is amending the animal drug regulations to reflect approval of an original new animal...

  14. 77 FR 15960 - Oral Dosage Form New Animal Drugs; Pergolide

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-19

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Pergolide AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is amending the animal drug regulations to reflect approval of an original new animal...

  15. 75 FR 67031 - Oral Dosage Form New Animal Drugs; Domperidone

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-01

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Domperidone AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is amending the animal drug regulations to reflect the original approval of a new...

  16. 76 FR 59023 - Oral Dosage Form New Animal Drugs; Tylosin

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-23

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Tylosin AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is amending the animal drug regulations to reflect approval of an original abbreviated new...

  17. 76 FR 40808 - Oral Dosage Form New Animal Drugs; Amprolium

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-12

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Amprolium AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is amending the animal drug regulations to reflect approval of an original abbreviated new...

  18. Biowaiver monographs for immediate release solid oral dosage forms: levofloxacin.

    PubMed

    Koeppe, Marcelle O; Cristofoletti, Rodrigo; Fernandes, Eduardo F; Storpirtis, Silvia; Junginger, Hans E; Kopp, Sabine; Midha, Kamal K; Shah, Vinod P; Stavchansky, Salomon; Dressman, Jennifer B; Barends, Dirk M

    2011-05-01

    Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing levofloxacin as the only active pharmaceutical ingredient (API) are reviewed. According to the current Biopharmaceutics Classification System, levofloxacin can be assigned to Class I. No problems with BE of IR levofloxacin formulations containing different excipients and produced by different manufacturing methods have been reported and hence the risk of bioinequivalence caused by these factors appears to be low. In addition, levofloxacin has a wide therapeutic index. On the basis of this evidence, a biowaiver is recommended for IR solid oral dosage forms containing levofloxacin as the single API provided that (a) the test product contains only excipients present in IR levofloxacin drug products that have been approved in International Conference on Harmonization (ICH) or associated countries and which have the same dosage form; (b) both the test and comparator dosage form are "very rapidly dissolving" or "rapidly dissolving" with similarity of the dissolution profiles demonstrated at pH 1.2, 4.5, and 6.8; and (c) if the test product contains polysorbates, it should be both qualitatively and quantitatively identical to its comparator in terms of polysorbate content.

  19. 75 FR 54492 - Oral Dosage Form New Animal Drugs; Tiamulin

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-08

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Tiamulin... (FDA) is amending the animal drug regulations to reflect approval of a supplemental new animal drug application (NADA) filed by Novartis Animal Health US, Inc. The supplemental NADA provides for use of...

  20. 76 FR 38554 - Oral Dosage Form New Animal Drugs; Amprolium

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Amprolium... (FDA) is amending the animal drug regulations to reflect approval of an original abbreviated new animal... requirements in 5 U.S.C. 801-808. List of Subjects in 21 CFR Part 520 Animal drugs. Therefore, under...

  1. 76 FR 78815 - Oral Dosage Form New Animal Drugs; Cyclosporine

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-20

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs... Administration (FDA) is amending the animal drug regulations to reflect approval of a new animal drug application (NADA) filed by Novartis Animal Health US, Inc. The NADA provides for the veterinary prescription use...

  2. Radiation-induced graft polymerization for the preparation of a highly efficient UHMWPE fibrous adsorbent for Cr(VI) removal

    NASA Astrophysics Data System (ADS)

    Gao, Qianhong; Hua, Jiangtao; Li, Rong; Xing, Zhe; Pang, Lijuan; Zhang, Mingxing; Xu, Lu; Wu, Guozhong

    2017-01-01

    A novel fibrous adsorbent containing amine and quaternary ammonium groups was prepared by radiation-induced graft of glycidyl methacrylate (GMA) onto ultra-high molecular weight polyethylene (UHMWPE) fiber and further modifying with triethylenetetramine (TETA) and glycidyl trimethylammonium chloride (GTA). The ATR-IR spectra and SEM observation demonstrated that amine and quaternary ammonium groups were immobilized onto the surface of UHMWPE fiber. The principal factors affecting the adsorption of Cr(VI) ions have been investigated including pH of the aqueous solution, contact time, temperature and coexisting anions. This novel fibrous adsorbent could effectively adsorb Cr(VI) in the range of pH 1-9, and the maximum adsorption capacity reached 295 mg/g at pH 3 and 25 °C based on the Langmuir isotherm. It was found that adsorption equilibrium could be achieved within 2 h for initial Cr(VI) of 100 mg/L, following the pseudo-second order model. The effect of coexisting anions (including SO42-, H2PO4-, NO3-and Cl-) on the uptake of Cr(VI) was investigated in detail. Additionally, the adsorption saturated fiber could be regenerated by soaking in 0.5 mol/L NaOH solution, and the adsorption performance of this adsorbent could be maintained at 90% after eight cycles of adsorption-desorption. ATR-IR and XPS analysis revealed that Cr(VI) ions were adsorbed on the fiber adsorbent through ion exchange mechanism.

  3. In Situ Investigation the Photolysis of the PAHs Adsorbed on Mangrove Leaf Surfaces by Synchronous Solid Surface Fluorimetry

    PubMed Central

    Wang, Ping; Wu, Tun-Hua; Zhang, Yong

    2014-01-01

    An established synchronous solid surface fluorimetry (S-SSF) was utilized for in situ study the photolysis processes of anthracene (An) and pyrene (Py) adsorbed on the leaf surfaces of Kandelia obovata seedlings (Ko) and Aegiceras corniculata (L.) Blanco seedlings (Ac). Experimental results demonstrated that the photolysis of An and Py adsorbed on the leaf surfaces of two mangrove species under the laboratory conditions, followed first-order kinetics with their photolysis rates in the order of Ac>Ko. In addition, with the same amount of substances, the photolysis rate of An adsorbed on the same mangrove leaf surfaces was much faster than the adsorbed Py. In order to investigate further, the photolysis processes of An and Py in water were also studied for comparison. And the photolysis of An and Py in water also followed first-order kinetics. Moreover, for the same initial amount, the photolysis rate of the PAH in water was faster than that adsorbed on the leaf surfaces of two mangrove species. Therefore, photochemical behaviors of PAHs were dependent not only on their molecular structures but also the physical-chemical properties of the substrates on which they are adsorbed. PMID:24404158

  4. Modeling Effective Dosages in Hormetic Dose-Response Studies

    PubMed Central

    Belz, Regina G.; Piepho, Hans-Peter

    2012-01-01

    Background Two hormetic modifications of a monotonically decreasing log-logistic dose-response function are most often used to model stimulatory effects of low dosages of a toxicant in plant biology. As just one of these empirical models is yet properly parameterized to allow inference about quantities of interest, this study contributes the parameterized functions for the second hormetic model and compares the estimates of effective dosages between both models based on 23 hormetic data sets. Based on this, the impact on effective dosage estimations was evaluated, especially in case of a substantially inferior fit by one of the two models. Methodology/Principal Findings The data sets evaluated described the hormetic responses of four different test plant species exposed to 15 different chemical stressors in two different experimental dose-response test designs. Out of the 23 data sets, one could not be described by any of the two models, 14 could be better described by one of the two models, and eight could be equally described by both models. In cases of misspecification by any of the two models, the differences between effective dosages estimates (0–1768%) greatly exceeded the differences observed when both models provided a satisfactory fit (0–26%). This suggests that the conclusions drawn depending on the model used may diverge considerably when using an improper hormetic model especially regarding effective dosages quantifying hormesis. Conclusions/Significance The study showed that hormetic dose responses can take on many shapes and that this diversity can not be captured by a single model without risking considerable misinterpretation. However, the two empirical models considered in this paper together provide a powerful means to model, prove, and now also to quantify a wide range of hormetic responses by reparameterization. Despite this, they should not be applied uncritically, but after statistical and graphical assessment of their adequacy. PMID

  5. Fluoride removal from aqueous solution by Al(III)-Zr(IV) binary oxide adsorbent

    NASA Astrophysics Data System (ADS)

    Zhu, Jiuya; Lin, Xiaoyan; Wu, Pengwei; Zhou, Qiusheng; Luo, Xuegang

    2015-12-01

    In this study, a novel binary oxide adsorbent of Al2O3-ZrO2 was prepared via coprecipitation followed by calcination method, and the calcination temperatures were investigated. The adsorbent was characterized by XRD, EDX and XPS. The batch adsorption experiments were carried out at different parameters, such as solution pH, adsorbent dose, contact time, initial fluoride concentration and adsorption temperature, to evaluate the fluoride removal performance. The results showed that the adsorption isotherm was better described by the linear Langmuir model, and a maximum adsorption capacity was 114.54 mg/g. The adsorption kinetics was well fitted by the linear pseudo-second-order, and the correlation coefficient value (R2) was 0.997. The thermodynamic parameters of ΔH0, ΔS0 and ΔG0 were calculated, which showed that the fluoride adsorption process was spontaneous and exothermic. And the possible adsorption mechanism of the adsorbent for fluoride could involve the ligand-exchange and ion-exchange based on the results in the study.

  6. Fate of Adsorbed U(VI) during Sulfidization of Lepidocrocite and Hematite

    PubMed Central

    2017-01-01

    The impact on U(VI) adsorbed to lepidocrocite (γ-FeOOH) and hematite (α-Fe2O3) was assessed when exposed to aqueous sulfide (S(-II)aq) at pH 8.0. With both minerals, competition between S(-II) and U(VI) for surface sites caused instantaneous release of adsorbed U(VI). Compared to lepidocrocite, consumption of S(-II)aq proceeded slower with hematite, but yielded maximum dissolved U concentrations that were more than 10 times higher, representing about one-third of the initially adsorbed U. Prolonged presence of S(-II)aq in experiments with hematite in combination with a larger release of adsorbed U(VI), enhanced the reduction of U(VI): after 24 h of reaction about 60–70% of U was in the form of U(IV), much higher than the 25% detected in the lepidocrocite suspensions. X-ray absorption spectra indicated that U(IV) in both hematite and lepidocrocite suspensions was not in the form of uraninite (UO2). Upon exposure to oxygen only part of U(IV) reoxidized, suggesting that monomeric U(IV) might have become incorporated in newly formed iron precipitates. Hence, sulfidization of Fe oxides can have diverse consequences for U mobility: in short-term, desorption of U(VI) increases U mobility, while reduction to U(IV) and its possible incorporation in Fe transformation products may lead to long-term U immobilization. PMID:28121137

  7. Physical and chemical regeneration of zeolitic adsorbents for dye removal in wastewater treatment.

    PubMed

    Wang, Shaobin; Li, Huiting; Xie, Sujuan; Liu, Shenglin; Xu, Longya

    2006-09-01

    Natural zeolite and synthetic zeolite, MCM-22, were employed as effective adsorbents for a basic dye, methylene blue, removal from wastewater. Two methods, Fenton oxidation and high temperature combustion, have been used for regeneration of used materials. It is found that MCM-22 exhibits equilibrium adsorption at 1.7 x 10(-4) mol g(-1), much higher than the adsorption of natural zeolite (5 x 10(-5) mol g(-1)) at initial dye concentration of 2.7 x 10(-5)M and 30 degrees C. Solution pH will affect the adsorption behaviour of MCM-22. Higher solution pH results in higher adsorption capacity. The regenerated adsorbents show different capacity depending on regeneration technique. Physical regeneration by high temperature combustion will be better than chemical regeneration using Fenton oxidation in producing effective adsorbents. Regeneration of MCM-22 by high temperature treatment can make the adsorbent exhibit comparable or superior adsorption capacity as compared to the fresh sample depending on the temperature and time. The optimal temperature and time will be 540 degrees C and 1h. The Fenton oxidation will recover 60% adsorption capacity. For natural zeolite, regeneration can not fully recover the adsorption capacity with the two techniques and the regenerated natural zeolites by the two techniques are similar, showing 60% adsorption capacity of fresh sample. Kinetic studies indicate that the adsorption follows pseudo-second-order kinetics.

  8. Fate of Adsorbed U(VI) during Sulfidization of Lepidocrocite and Hematite.

    PubMed

    Alexandratos, Vasso G; Behrends, Thilo; Van Cappellen, Philippe

    2017-02-21

    The impact on U(VI) adsorbed to lepidocrocite (γ-FeOOH) and hematite (α-Fe2O3) was assessed when exposed to aqueous sulfide (S(-II)aq) at pH 8.0. With both minerals, competition between S(-II) and U(VI) for surface sites caused instantaneous release of adsorbed U(VI). Compared to lepidocrocite, consumption of S(-II)aq proceeded slower with hematite, but yielded maximum dissolved U concentrations that were more than 10 times higher, representing about one-third of the initially adsorbed U. Prolonged presence of S(-II)aq in experiments with hematite in combination with a larger release of adsorbed U(VI), enhanced the reduction of U(VI): after 24 h of reaction about 60-70% of U was in the form of U(IV), much higher than the 25% detected in the lepidocrocite suspensions. X-ray absorption spectra indicated that U(IV) in both hematite and lepidocrocite suspensions was not in the form of uraninite (UO2). Upon exposure to oxygen only part of U(IV) reoxidized, suggesting that monomeric U(IV) might have become incorporated in newly formed iron precipitates. Hence, sulfidization of Fe oxides can have diverse consequences for U mobility: in short-term, desorption of U(VI) increases U mobility, while reduction to U(IV) and its possible incorporation in Fe transformation products may lead to long-term U immobilization.

  9. Carbonaceous adsorbent regeneration and halocarbon displacement by hydrocarbon gases

    DOEpatents

    Senum, G.I.; Dietz, R.N.

    1994-04-05

    This invention describes a process for regeneration of halocarbon bearing carbonaceous adsorbents through which a carbonaceous adsorbent is contacted with hydrocarbon gases, preferably propane, butane and pentane at near room temperatures and at atmospheric pressure. As the hydrocarbon gases come in contact with the adsorbent, the hydrocarbons displace the halocarbons by physical adsorption. As a result of using this process, the halocarbon concentration and the hydrocarbon eluant is increased thereby allowing for an easier recovery of pure halocarbons. By using the process of this invention, carbonaceous adsorbents can be regenerated by an inexpensive process which also allows for subsequent re-use of the recovered halocarbons. 8 figures.

  10. Carbonaceous adsorbent regeneration and halocarbon displacement by hydrocarbon gases

    DOEpatents

    Senum, Gunnar I.; Dietz, Russell N.

    1994-01-01

    This invention describes a process for regeneration of halocarbon bearing carbonaceous adsorbents through which a carbonaceous adsorbent is contacted with hydrocarbon gases, preferably propane, butane and pentane at near room temperatures and at atmospheric pressure. As the hydrocarbon gases come in contact with the adsorbent, the hydrocarbons displace the halocarbons by physical adsorption. As a result of using this process, the halocarbon concentration and the hydrocarbon eluant is increased thereby allowing for an easier recovery of pure halocarbons. By using the process of this invention, carbonaceous adsorbents can be regenerated by an inexpensive process which also allows for subsequent re-use of the recovered halocarbons.

  11. Testing of chemically treated adsorbent air purifiers

    SciTech Connect

    Kelly, T.J. . Dept. of Atmospheric Science and Applied Technology); Kinkead, D.A. )

    1993-07-01

    New highly sensitive continuous monitors permit testing of air filters at parts-per-billion contaminant concentrations. This article describes testing of air purification filters intended for use in the National Archives 2 building in College Park, Maryland, using a test procedure that simulates the actual conditions of use. This test demonstrates both the effectiveness of the adsorbers at low contaminant levels, and the capability of existing instruments for conducting such tests. ASHRAE TC 2.3 (Gaseous Air Contaminants and Gas Contaminant Removal Equipment) is currently sponsoring research projects (follow-on studies to ASHRAE Project RP-674) aimed at developing a standard that will test and rate the performance of different types of gas phase air purification equipment at low concentrations. The work detailed in this article represents a first of this type of testing and a technical benchmark that may aid in the further development of ASHRAE gas phase performance standards.

  12. The condensation of water on adsorbed viruses.

    PubMed

    Alonso, José María; Tatti, Francesco; Chuvilin, Andrey; Mam, Keriya; Ondarçuhu, Thierry; Bittner, Alexander M

    2013-11-26

    The wetting and dewetting behavior of biological nanostructures and to a greater degree single molecules is not well-known even though their contact with water is the basis for all biology. Here, we show that environmental electron microscopy (EM) can be applied as a means of imaging the condensation of water onto viruses. We captured the formation of submicrometer water droplets and filaments on single viral particles by environmental EM and by environmental transmission EM. The condensate structures are compatible with capillary condensation between adsorbed virus particles and with known droplet shapes on patterned surfaces. Our results confirm that such droplets exist down to <50 nm. The viruses preserved their shape after a condensation/evaporation cycle as expected from their stability in air and water. Moreover we developed procedures that overcome problems of beam damage and of resolving structures with a low atomic number.

  13. Carbon Dioxide Capture Adsorbents: Chemistry and Methods.

    PubMed

    Patel, Hasmukh A; Byun, Jeehye; Yavuz, Cafer T

    2016-12-21

    Excess carbon dioxide (CO2 ) emissions and their inevitable consequences continue to stimulate hard debate and awareness in both academic and public spaces, despite the widespread lack of understanding on what really is needed to capture and store the unwanted CO2 . Of the entire carbon capture and storage (CCS) operation, capture is the most costly process, consisting of nearly 70 % of the price tag. In this tutorial review, CO2 capture science and technology based on adsorbents are described and evaluated in the context of chemistry and methods, after briefly introducing the current status of CO2 emissions. An effective sorbent design is suggested, whereby six checkpoints are expected to be met: cost, capacity, selectivity, stability, recyclability, and fast kinetics.

  14. Trends in adsorbate induced core level shifts

    NASA Astrophysics Data System (ADS)

    Nilsson, Viktor; Van den Bossche, Maxime; Hellman, Anders; Grönbeck, Henrik

    2015-10-01

    Photoelectron core level spectroscopy is commonly used to monitor atomic and molecular adsorption on metal surfaces. As changes in the electron binding energies are convoluted measures with different origins, calculations are often used to facilitate the decoding of experimental signatures. The interpretation could in this sense benefit from knowledge on trends in surface core level shifts for different metals and adsorbates. Here, density functional theory calculations have been used to systematically evaluate core level shifts for (111) and (100) surfaces of 3d, 4d, and 5d transition metals upon CO, H, O and S adsorption. The results reveal trends and several non-intuitive cases. Moreover, the difficulties correlating core level shifts with charging and d-band shifts are underlined.

  15. Development of a new adsorbent from agro-industrial waste and its potential use in endocrine disruptor compound removal.

    PubMed

    Rovani, Suzimara; Censi, Monique T; Pedrotti, Sidnei L; Lima, Eder C; Cataluña, Renato; Fernandes, Andreia N

    2014-04-30

    A new activated carbon (AC) material was prepared by pyrolysis of a mixture of coffee grounds, eucalyptus sawdust, calcium hydroxide and soybean oil at 800°C. This material was used as adsorbent for the removal of the endocrine disruptor compounds 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) from aqueous solutions. The carbon material was characterized by scanning electron microscopy (SEM), infrared spectroscopy (FTIR), N2 adsorption/desorption curves and point of zero charge (pHPZC). Variables including the initial pH of the adsorbate solutions, adsorbent masses and contact time were optimized. The optimum range of initial pH for removal of endocrine disruptor compounds (EDC) was 2.0-11.0. The kinetics of adsorption were investigated using general order, pseudo first-order and pseudo-second order kinetic models. The Sips isotherm model gave the best fits of the equilibrium data (298K). The maximum amounts of E2 and EE2 removed at 298K were 7.584 (E2) and 7.883mgg(-1) (EE2) using the AC as adsorbent. The carbon adsorbent was employed in SPE (solid phase extraction) of E2 and EE2 from aqueous solutions.

  16. HYDROGEN GENERATION FROM PLASMATRON REFORMERS: A PROMISING TECHNOLOGY FOR NOX ADSORBER REGENERATION AND OTHER AUTOMOTIVE APPLICATIONS

    SciTech Connect

    Bromberg, L.; Crane, S; Rabinovich, A.; Kong, Y; Cohn, D; Heywood, J; Alexeev, N.; Samokhin, A.

    2003-08-24

    Plasmatron reformers are being developed at MIT and ArvinMeritor [1]. In these reformers a special low power electrical discharge is used to promote partial oxidation conversion of hydrocarbon fuels into hydrogen and CO. The partial oxidation reaction of this very fuel rich mixture is difficult to initiate. The plasmatron provides continuous enhanced volume initiation. To minimize electrode erosion and electrical power requirements, a low current, high voltage discharge with wide area electrodes is used. The reformers operate at or slightly above atmospheric pressure. Plasmatron reformers provide the advantages of rapid startup and transient response; efficient conversion of the fuel to hydrogen rich gas; compact size; relaxation or elimination of reformer catalyst requirements; and capability to process difficult to reform fuels, such as diesel and bio-oils. These advantages facilitate use of onboard hydrogen-generation technology for diesel exhaust after-treatment. Plasma-enhanced reformer technology can provide substantial conversion even without the use of a catalyst. Recent progress includes a substantial decrease in electrical power consumption (to about 200 W), increased flow rate (above 1 g/s of diesel fuel corresponding to approximately 40 kW of chemical energy), soot suppression and improvements in other operational features.. Plasmatron reformer technology has been evaluated for regeneration of NOx adsorber after-treatment systems. At ArvinMeritor tests were performed on a dual-leg NOx adsorber system using a Cummins 8.3L diesel engine both in a test cell and on a vehicle. A NOx adsorber system was tested using the plasmatron reformer as a regenerator and without the reformer i.e., with straight diesel fuel based regeneration as the baseline case. The plasmatron reformer was shown to improve NOx regeneration significantly compared to the baseline diesel case. The net result of these initial tests was a significant decrease in fuel penalty, roughly 50% at

  17. Magnesium oxide-impregnated tuff soil-derived ceramic: a novel cadmium(II) adsorbing media

    NASA Astrophysics Data System (ADS)

    Salim, Md; Bhakta, Jatindra N.; Maneesh, Namburath; Munekage, Yukihiro; Motomura, Kevin

    2015-07-01

    The contamination of cadmium (Cd) in the aquatic environment is one of the serious environmental and human health's risks. The present study attempted to develop the potential magnesium oxide (MgO)-impregnated tuff soil-derived ceramic (MITDC)-based novel adsorbent media for adsorbing higher rate of cadmium [Cd(II)] from water phase. A potential MITDC adsorbent media was developed using volcanic raw tuff soil and its Cd(II) adsorption capacity from water phase was evaluated comparing with the raw tuff soil. A series of studies were carried out in an agitated batch method at 20 ± 2 °C to characterize the adsorption capacity of MITDC under different conditions of factors, such as contact time (0-360 min), initial pH (3-11) of solution, dose of MITDC (2, 5, 7.5 and 10 g/L), and initial concentration of Cd(II) (5, 10, 20, 30, and 40 mg/L), influencing the adsorption mechanism. MITDC exhibited the equilibrium state of maximum Cd(II) adsorption at the contact time 120 min and pH 4.7 (removed 98.2 % Cd) when initial Cd(II) concentration was 10 mg/L in the present study. The dose of 7.5 g MITDC/L showed maximum removal of Cd(II) from water. Experimental data were described by the Freundlich and the Langmuir isotherms and equilibrium data fitted well with the Langmuir model (R 2 = 0.996). The Cd(II) adsorption capacity of MITDC was 31.25 mg/g. The high Cd(II) adsorption capacity indicated that novel MITDC could be used as a potential ceramic adsorbent media to remove high rate of Cd(II) from aqueous phase.

  18. Nanoclay-Based Solid-Amine Adsorbents for Carbon Dioxide Capture

    NASA Astrophysics Data System (ADS)

    Roth, Elliot A.

    The objective of this research was to develop an efficient, low cost, recyclable solid sorbent for carbon dioxide adsorption from large point sources, such as coal-fired power plants. The current commercial way to adsorb CO 2 is to use a liquid amine or ammonia process. These processes are used in industry in the "sweetening" of natural gas, but liquid based technologies are not economically viable in the adsorption of CO2 from power plants due to the extremely large volume of CO2 and the inherent high regeneration costs of cycling the sorbent. Therefore, one of the main objectives of this research was to develop a novel sorbent that can be cycled and uses very little energy for regeneration. The sorbent developed here is composed of a nanoclay (montmorillonite), commonly used in the production of polymer nanocomposites, grafted with commercially available amines. (3-aminopropyl) trimethoxysilane (APTMS) was chemically grafted to the edge hydroxyl groups of the clay. While another amine, polyethylenimine (PEI), was attached to the surface of the clay by electrostatic interactions. To confirm the attachment of amines to the clay, the samples were characterized using FTIR and the corresponding peaks for amines were observed. The amount of amine loaded onto the support was determined by TGA techniques. The treated clay was initially analyzed for CO2 adsorption in a pure CO 2 stream. The adsorption temperatures that had the highest adsorption capacity were determined to be between 75°C and 100°C for all of the samples tested at atmospheric pressure. The maximum CO2 adsorption capacity observed was with nanoclay treated with both APTMS and PEI at 85°C. In a more realistic flue gas of 10% CO2 and 90% N2, the adsorbents had essentially the same overall CO2 adsorption capacity indicating that the presence of nitrogen did not hinder the adsorption of CO2. Adsorption studies in pure CO2 at room temperature under pressure from 40-300 PSI were also conducted. The average

  19. Batch technique to evaluate the efficiency of different natural adsorbents for defluoridation from groundwater

    NASA Astrophysics Data System (ADS)

    Kumar, Pankaj; Saraswat, Chitresh; Mishra, Binaya Kumar; Avtar, Ram; Patel, Hiral; Patel, Asha; Sharma, Tejal; Patel, Roshni

    2016-09-01

    Fluoride pollution (with concentration >1.0 mg/L) in groundwater has become a global threat in the recent past due to the lesser availability of potable groundwater resource. In between several defluoridation techniques discovered so far, the adsorption process proved to be most economic and efficient. This study is an effort to evaluate defluoridation efficiency of powdered rice husk, fine chopped rice husk and sawdust by the batch adsorption process. Optimum defluoridation capacity is achieved by optimizing various parameters, viz. dose of adsorbent, pH, contact time and initial concentration. It was found that all three materials can be employed for the defluoridation technique, but powdered rice husk is the best adsorbent in the midst of all three. Powdered rice husk showed fluoride removal efficiency ranging between 85 and 90 % in the contact period of 7 h only in conditions of all optimized parameter. Following this parameter optimization, adsorption efficiency was also evaluated at natural pH of groundwater to minimize the cost of defluoridation. No significant difference was found between fluoride adsorption at optimized pH (pH = 4) and natural one (pH = 7), which concludes that powdered rice husk can be efficiently used for the defluoridation technique at field scale. The adsorption isotherm using this adsorbent perfectly followed Langmuir isotherms. The value of calculated separation factor also suggests the favourable adsorption of fluoride onto this adsorbent under the conditions used for the experiments. The field application for defluoridation of groundwater using this adsorbent (based on pH of natural groundwater there and seasonal variation of temperature) showed the high success rate.

  20. 1p36 tumor suppression--a matter of dosage?

    PubMed

    Henrich, Kai-Oliver; Schwab, Manfred; Westermann, Frank

    2012-12-01

    A broad range of human malignancies is associated with nonrandom 1p36 deletions, suggesting the existence of tumor suppressors encoded in this region. Evidence for tumor-specific inactivation of 1p36 genes in the classic "two-hit" manner is scarce; however, many tumor suppressors do not require complete inactivation but contribute to tumorigenesis by partial impairment. We discuss recent data derived from both human tumors and functional cancer models indicating that the 1p36 genes CHD5, CAMTA1, KIF1B, CASZ1, and miR-34a contribute to cancer development when reduced in dosage by genomic copy number loss or other mechanisms. We explore potential interactions among these candidates and propose a model where heterozygous 1p36 deletion impairs oncosuppressive pathways via simultaneous downregulation of several dosage-dependent tumor suppressor genes.

  1. Regulatory perspectives on acceptability testing of dosage forms in children.

    PubMed

    Kozarewicz, Piotr

    2014-08-05

    Current knowledge about the age-appropriateness of different dosage forms is still fragmented or limited. Applicants are asked to demonstrate that the target age group(s) can manage the dosage form or propose an alternative strategy. However, questions remain about how far the applicant must go and what percentage of patients must find the strategy 'acceptable'. The aim of this overview is to provide an update on current thinking and understanding of the problem, and discuss issues relating to the acceptability testing. This overview should be considered as means to start a wider discussion which hopefully will result in a harmonised, globally acceptable approach for confirmation of the acceptability in the future.

  2. Biowaiver monographs for immediate release solid oral dosage forms: prednisone.

    PubMed

    Vogt, M; Derendorf, H; Krämer, J; Junginger, H E; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M

    2007-06-01

    Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing prednisone are reviewed. Due to insufficient data prednisone cannot be definitively classified according to the current Biopharmaceutics Classification System (BCS) criteria as both the solubility and the permeability of prednisone are on the borderline of the present criteria of BCS Class I. Prednisone's therapeutic indications and therapeutic index, pharmacokinetics and the possibility of excipient interactions were also taken into consideration. Available evidence indicates that a biowaiver for IR solid oral dosage forms formulated with the excipients tabulated in this article would be unlikely to expose patients to undue risks.

  3. RFID Tag Helix Antenna Sensors for Wireless Drug Dosage Monitoring.

    PubMed

    Huang, Haiyu; Zhao, Peisen; Chen, Pai-Yen; Ren, Yong; Liu, Xuewu; Ferrari, Mauro; Hu, Ye; Akinwande, Deji

    2014-01-01

    Miniaturized helix antennas are integrated with drug reservoirs to function as RFID wireless tag sensors for real-time drug dosage monitoring. The general design procedure of this type of biomedical antenna sensors is proposed based on electromagnetic theory and finite element simulation. A cost effective fabrication process is utilized to encapsulate the antenna sensor within a biocompatible package layer using PDMS material, and at the same time form a drug storage or drug delivery unit inside the sensor. The in vitro experiment on two prototypes of antenna sensor-drug reservoir assembly have shown the ability to monitor the drug dosage by tracking antenna resonant frequency shift from 2.4-2.5-GHz ISM band with realized sensitivity of 1.27 [Formula: see text] for transdermal drug delivery monitoring and 2.76-[Formula: see text] sensitivity for implanted drug delivery monitoring.

  4. Six3 dosage mediates the pathogenesis of holoprosencephaly.

    PubMed

    Geng, Xin; Acosta, Sandra; Lagutin, Oleg; Gil, Hyea Jin; Oliver, Guillermo

    2016-12-01

    Holoprosencephaly (HPE) is defined as the incomplete separation of the two cerebral hemispheres. The pathology of HPE is variable and, based on the severity of the defect, HPE is divided into alobar, semilobar, and lobar. Using a novel hypomorphic Six3 allele, we demonstrate in mice that variability in Six3 dosage results in different HPE phenotypes. Furthermore, we show that whereas the semilobar phenotype results from severe downregulation of Shh expression in the rostral diencephalon ventral midline, the alobar phenotype is caused by downregulation of Foxg1 expression in the anterior neural ectoderm. Consistent with these results, in vivo activation of the Shh signaling pathway rescued the semilobar phenotype but not the alobar phenotype. Our findings show that variations in Six3 dosage result in different forms of HPE.

  5. Practical issues of hyperspectral imaging analysis of solid dosage forms.

    PubMed

    Amigo, José Manuel

    2010-09-01

    Hyperspectral imaging techniques have widely demonstrated their usefulness in different areas of interest in pharmaceutical research during the last decade. In particular, middle infrared, near infrared, and Raman methods have gained special relevance. This rapid increase has been promoted by the capability of hyperspectral techniques to provide robust and reliable chemical and spatial information on the distribution of components in pharmaceutical solid dosage forms. Furthermore, the valuable combination of hyperspectral imaging devices with adequate data processing techniques offers the perfect landscape for developing new methods for scanning and analyzing surfaces. Nevertheless, the instrumentation and subsequent data analysis are not exempt from issues that must be thoughtfully considered. This paper describes and discusses the main advantages and drawbacks of the measurements and data analysis of hyperspectral imaging techniques in the development of solid dosage forms.

  6. Anomalous fast dynamics of adsorbate overlayers near an incommensurate structural transition.

    PubMed

    Granato, Enzo; Ying, S C; Elder, K R; Ala-Nissila, T

    2013-09-20

    We investigate the dynamics of a compressively strained adsorbed layer on a periodic substrate via a simple two-dimensional model that admits striped and hexagonal incommensurate phases. We show that the mass transport is superfast near the striped-hexagonal phase boundary and in the hexagonal phase. For an initial step profile separating a bare substrate region (or "hole") from the rest of a striped incommensurate phase, the superfast domain wall dynamics leads to a bifurcation of the initial step profile into two interfaces or profiles propagating in opposite directions with a hexagonal phase in between. This yields a theoretical understanding of the recent experiments for the Pb/Si(111) system.

  7. Global analysis of X-chromosome dosage compensation

    PubMed Central

    Gupta, Vaijayanti; Parisi, Michael; Sturgill, David; Nuttall, Rachel; Doctolero, Michael; Dudko, Olga K; Malley, James D; Eastman, P Scott; Oliver, Brian

    2006-01-01

    Background Drosophila melanogaster females have two X chromosomes and two autosome sets (XX;AA), while males have a single X chromosome and two autosome sets (X;AA). Drosophila male somatic cells compensate for a single copy of the X chromosome by deploying male-specific-lethal (MSL) complexes that increase transcription from the X chromosome. Male germ cells lack MSL complexes, indicating that either germline X-chromosome dosage compensation is MSL-independent, or that germ cells do not carry out dosage compensation. Results To investigate whether dosage compensation occurs in germ cells, we directly assayed X-chromosome transcripts using DNA microarrays and show equivalent expression in XX;AA and X;AA germline tissues. In X;AA germ cells, expression from the single X chromosome is about twice that of a single autosome. This mechanism ensures balanced X-chromosome expression between the sexes and, more importantly, it ensures balanced expression between the single X chromosome and the autosome set. Oddly, the inactivation of an X chromosome in mammalian females reduces the effective X-chromosome dose and means that females face the same X-chromosome transcript deficiency as males. Contrary to most current dosage-compensation models, we also show increased X-chromosome expression in X;AA and XX;AA somatic cells of Caenorhabditis elegans and mice. Conclusion Drosophila germ cells compensate for X-chromosome dose. This occurs by equilibrating X-chromosome and autosome expression in X;AA cells. Increased expression of the X chromosome in X;AA individuals appears to be phylogenetically conserved. PMID:16507155

  8. Interaction of sodium polyacrylate adsorbed on TiO2 with cationic and anionic surfactants.

    PubMed

    Li, Haiyan; Tripp, Carl P

    2004-11-23

    Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) was used to identify the structures formed during the adsorption of sodium polyacrylate (NaPA) on charged TiO2 particles and to determine the subsequent interaction of the adsorbed polymer structure with cationic and anionic surfactants. The nature of the polymer structure was deduced from the adsorbed amount in tandem with the information obtained from monitoring the change in the relative intensity of the COO- and COOH infrared bands. In particular, it is found that the relative number of COO- and COOH groups on the polymer backbone for the adsorbed state differs from that of the same polymer in solution. This difference is due to a shift in the population of COO-/COOH groups on the polymer backbone that arises when the COO- groups bind to positively charged sites on the surface. A change in the number COO-/COOH groups on the polymer is thus related to a change in the bound fraction of polymer. It is shown that the initial NaPA approaching the bare surface adopts a flat conformation with high bound fraction. Once the bare sites on the surface are covered, the accommodation of additional polymer on the surface requires the existing adsorbed layer to adopt a conformation with a lower bound fraction. When the adsorbed NaPA is probed with a solution containing the anionic surfactant sodium dodecyl sulfate (SDS), the SDS competes for surface sites and displaces some of the bound NaPA segments from the surface, giving rise to an polymer layer adsorbed with an even lower bound fraction. In contrast, addition of a solution containing the cationic surfactant cetyltrimethylammonium bromide (CTAB) results in the binding of the surfactant directly to the free COO- sites on the adsorbed polymer backbone. Confirmation of a direct interaction of the CTAB headgroup with the free COO- groups of the polymer is provided by intensity changes in the headgroup IR bands of the CTAB.

  9. Dosage Compensation in the African Malaria Mosquito Anopheles gambiae

    PubMed Central

    Rose, Graham; Krzywinska, Elzbieta; Kim, Jan; Revuelta, Loic; Ferretti, Luca; Krzywinski, Jaroslaw

    2016-01-01

    Dosage compensation is the fundamental process by which gene expression from the male monosomic X chromosome and from the diploid set of autosomes is equalized. Various molecular mechanisms have evolved in different organisms to achieve this task. In Drosophila, genes on the male X chromosome are upregulated to the levels of expression from the two X chromosomes in females. To test whether a similar mechanism is operating in immature stages of Anopheles mosquitoes, we analyzed global gene expression in the Anopheles gambiae fourth instar larvae and pupae using high-coverage RNA-seq data. In pupae of both sexes, the median expression ratios of X-linked to autosomal genes (X:A) were close to 1.0, and within the ranges of expression ratios between the autosomal pairs, consistent with complete compensation. Gene-by-gene comparisons of expression in males and females revealed mild female bias, likely attributable to a deficit of male-biased X-linked genes. In larvae, male to female ratios of the X chromosome expression levels were more female biased than in pupae, suggesting that compensation may not be complete. No compensation mechanism appears to operate in male germline of early pupae. Confirmation of the existence of dosage compensation in A. gambiae lays the foundation for research into the components of dosage compensation machinery in this important vector species. PMID:26782933

  10. Status of dosage compensation of X chromosome in bovine genome.

    PubMed

    Ka, Sojeong; Ahn, Hyeonju; Seo, Minseok; Kim, Heebal; Kim, Jin Nam; Lee, Hyun-Jeong

    2016-08-01

    Dosage compensation system with X chromosome upregulation and inactivation have evolved to overcome the genetic imbalance between sex chromosomes in both male and female of mammals. Although recent development of chromosome-wide technologies has allowed us to test X upregulation, discrete data processing and analysis methods draw disparate conclusions. A series of expression studies revealed status of dosage compensation in some species belonging to monotremes, marsupials, rodents and primates. However, X upregulation in the Artiodactyla order including cattle have not been studied yet. In this study, we surveyed the genome-wide transcriptional upregulation in X chromosome in cattle RNA-seq data using different gene filtration methods. Overall examination of RNA-seq data revealed that X chromosome in the pituitary gland expressed more genes than in other peripheral tissues, which was consistent with the previous results observed in human and mouse. When analyzed with globally expressed genes, a median X:A expression ratio was 0.94. The ratio of 1-to-1 ortholog genes between chicken and mammals, however, showed considerable reduction to 0.68. These results indicate that status of dosage compensation for cattle is not deviated from those found in rodents and primate, and this is consistent with the evolutionary history of cattle.

  11. Biowaiver monographs for immediate release solid oral dosage forms: rifampicin.

    PubMed

    Becker, C; Dressman, J B; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Barends, D M

    2009-07-01

    Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of new multisource and reformulated immediate release (IR) solid oral dosage forms containing rifampicin as the only Active Pharmaceutical Ingredient (API) are reviewed. Rifampicin's solubility and permeability, its therapeutic use and index, pharmacokinetics, excipient interactions and reported BE/bioavailability (BA) problems were taken into consideration. Solubility and absolute BA data indicate that rifampicin is a BCS Class II drug. Of special concern for biowaiving is that many reports of failure of IR solid oral dosage forms of rifampicin to meet BE have been published and the reasons for these failures are yet insufficiently understood. Moreover, no reports were identified in which in vitro dissolution was shown to be predictive of nonequivalence among products. Therefore, a biowaiver based approval of rifampicin containing IR solid oral dosage forms cannot be recommended for either new multisource drug products or for major scale-up and postapproval changes (variations) to existing drug products.

  12. Biowaiver monographs for immediate release solid oral dosage forms: pyrazinamide.

    PubMed

    Becker, C; Dressman, J B; Amidon, G L; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Barends, D M

    2008-09-01

    Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing pyrazinamide as the only active pharmaceutical ingredient (API) are reviewed. Pyrazinamide is BCS Class III, with linear absorption over a wide dosing range. The risk of bioinequivalence is estimated to be low. Depending on the definition used, pyrazinamide can be classified as a narrow therapeutic index (NTI) drug, which is usually a caveat to biowaiving but may be deemed acceptable if the Summary of Product Characteristics (SmPCs) of the test product stipulates the need for regular monitoring of liver function. It is concluded that a biowaiver can be recommended for IR solid oral dosage only when the test product (a) contains only excipients present in pyrazinamide IR solid oral drug products approved in ICH or associated countries, (b) these excipients are present in amounts normally used in IR solid oral dosage forms, (c) the test product is very rapidly dissolving, (d) the SmPC of the test product indicates the need for monitoring of the patient's liver function.

  13. Biowaiver Monographs for Immediate Release Solid Oral Dosage Forms: Levetiracetam.

    PubMed

    Petruševska, Marija; Berglez, Sandra; Krisch, Igor; Legen, Igor; Megušar, Klara; Peternel, Luka; Abrahamsson, Bertil; Cristofoletti, Rodrigo; Groot, D W; Kopp, Sabine; Langguth, Peter; Mehta, Mehul; Polli, James E; Shah, Vinod P; Dressman, Jennifer

    2015-09-01

    Literature and experimental data relevant for the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing levetiracetam are reviewed. Data on solubility and permeability suggest that levetiracetam belongs to class I of the biopharmaceutical classification system (BCS). Levetiracetam's therapeutic use, its wide therapeutic index, and its favorable pharmacokinetic properties make levetiracetam a valid candidate for the BCS-based biowaiver approach. Further, no BE studies with levetiracetam IR formulations in which the test formulation failed to show BE with the comparator have been reported in the open literature. On the basis of the overall evidence, it appears unlikely that a BCS-based biowaiver approach for levetiracetam IR solid oral dosage forms formulated with established excipients would expose patients to undue risks. Thus, the BCS-based biowaiver approach procedure is recommended for IR solid oral dosage form containing levetiracetam, provided the excipients in the formulation are also present in products that have been approved in countries belonging to or associated with the International Committee on Harmonization and are used in their usual quantities, and provided the dissolution profiles of the test and reference product comply with the current requirements for BCS-based biowaivers.

  14. Gastric emptying of multi-particulate dosage forms.

    PubMed

    Newton, J Michael

    2010-08-16

    The evidence in the literature for the concept that multi-particulate dosage forms below a specific size empty from the stomach as if they were liquids and hence have the potential to provide the best solution to the formulation of controlled release oral dosage forms, has been considered. There is some evidence that particles less than 1.0mm provide a more rapid response than larger size particles but there is also evidence that this is not always the case and that rapid and reproducible gastric emptying of small particles does not always occur when they are administered. There is strong evidence that food can delay the gastric emptying of multi-particulate systems. Some of the misconception for gastric emptying performance of multi-particulate system is shown to be related to the limitation of the study design and limitation of the way the data is processed. Nevertheless, there is clear evidence that multi-particulate systems can provide effective oral controlled release dosage forms. There is still some way to go with experimental techniques which would allow a definitive answer to the issue of how the variability of the gastric emptying of multi-particulate systems of less than 2.0mm arises.

  15. Spectrophotometric Assay of Mebendazole in Dosage Forms Using Sodium Hypochlorite

    NASA Astrophysics Data System (ADS)

    Swamy, N.; Prashanth, K. N.; Basavaiah, K.

    2014-07-01

    A simple, selective and sensitive spectrophotometric method is described for the determination of mebendazole (MBD) in bulk drug and dosage forms. The method is based on the reaction of MBD with hypochlorite in the presence of sodium bicarbonate to form the chloro derivative of MBD, followed by the destruction of the excess hypochlorite by nitrite ion. The color was formed by the oxidation of iodide with the chloro derivative of MBD to iodine in the presence of starch and forming the blue colored product, which was measured at 570 nm. The optimum conditions that affect the reaction were ascertained and, under these conditions, a linear relationship was obtained in the concentration range of 1.25-25.0·g/ml MBD. The calculated molar absorptivity and Sandell sensitivity values are 9.56·103 l·mol-1·cm-1 and 0.031 μg/cm2, respectively. The limits of detection and quantification are 0.11 and 0.33 μg/ml, respectively. The proposed method was applied successfully to the determination of MBD in bulk drug and dosage forms, and no interference was observed from excipients present in the dosage forms. The reliability of the proposed method was further checked by parallel determination by the reference method and also by recovery studies.

  16. Metal adsorbent for alkaline etching aqua solutions of Si wafer

    NASA Astrophysics Data System (ADS)

    Tamada, Masao; Ueki, Yuji; Seko, Noriaki; Takeda, Toshihide; Kawano, Shin-ichi

    2012-08-01

    High performance adsorbent is expected to be synthesized for the removal of Ni and Cu ions from strong alkaline solution used in the surface etching process of Si wafer. Fibrous adsorbent was synthesized by radiation-induce emulsion graft polymerization onto polyethylene nonwoven fabric and subsequent amination. The reaction condition was optimized using 30 L reaction vessel and nonwoven fabric, 0.3 m width and 18 m long. The resulting fibrous adsorbent was evaluated by 48 wt% NaOH and KOH contaminated with Ni and Cu ions, respectively. The concentration levels of Ni and Cu ions was reduced to less than 1 μg/kg (ppb) at the flow rate of 10 h-1 in space velocity. The life of adsorbent was 30 times higher than that of the commercialized resin. This novel adsorbent was commercialized as METOLATE® since the ability of adsorption is remarkably higher than that of commercial resin used practically in Si wafer processing.

  17. Single and binary adsorption of proteins on ion-exchange adsorbent: The effectiveness of isothermal models.

    PubMed

    Liang, Juan; Fieg, Georg; Shi, Qing-Hong; Sun, Yan

    2012-09-01

    Simultaneous and sequential adsorption equilibria of single and binary adsorption of bovine serum albumin and bovine hemoglobin on Q Sepharose FF were investigated in different buffer constituents and initial conditions. The results in simultaneous adsorption showed that both proteins underwent competitive adsorption onto the adsorbent following greatly by protein-surface interaction. Preferentially adsorbed albumin complied with the universal rule of ion-exchange adsorption whereas buffer had no marked influence on hemoglobin adsorption. Moreover, an increase in initial ratios of proteins was benefit to a growth of adsorption density. In sequential adsorption, hemoglobin had the same adsorption densities as single-component adsorption. It was attributed to the displacement of preadsorbed albumin and multiple layer adsorption of hemoglobin. Three isothermal models (i.e. extended Langmuir, steric mass-action, and statistical thermodynamic (ST) models) were introduced to describe the ion-exchange adsorption of albumin and hemoglobin mixtures. The results suggested that extended Langmuir model gave the lowest deviation in describing preferential adsorption of albumin at a given salt concentration while steric mass-action model could very well describe the salt effect in albumin adsorption. For weaker adsorbed hemoglobin, ST model was the preferred choice. In concert with breakthrough data, the research further revealed the complexity in ion-exchange adsorption of proteins.

  18. Food-processes wastewaters treatment using food solid-waste materials as adsorbents or absorbents

    NASA Astrophysics Data System (ADS)

    Rapti, Ilaira; Georgopoulos, Stavros; Antonopoulou, Maria; Konstantinou, Ioannis; Papadaki, Maria

    2016-04-01

    The wastewaters generated by olive-mills during the production of olive oil, wastewaters from a dairy and a cow-farm unit and wastewaters from a small food factory have been treated by means of selected materials, either by-products of the same units, or other solid waste, as absorbents or adsorbents in order to identify the capacity of those materials to remove organic load and toxicity from the aforementioned wastewaters. The potential of both the materials used as absorbents as well as the treated wastewaters to be further used either as fertilizers or for agricultural irrigation purposes are examined. Dry olive leaves, sheep wool, rice husks, etc. were used either in a fixed-bed or in a stirred batch arrangemen,t employing different initial concentrations of the aforementioned wastewaters. The efficiency of removal was assessed using scpectrophotometric methods and allium test phytotoxicity measurements. In this presentation the response of each material employed is shown as a function of absorbent/adsorbent quantity and kind, treatment time and wastewater kind and initial organic load. Preliminary results on the potential uses of the adsorbents/absorbents and the treated wastewaters are also shown. Keywords: Olive-mill wastewaters, dairy farm wastewaters, olive leaves, zeolite, sheep wool

  19. Biopharmaceutical considerations and characterizations in development of colon targeted dosage forms for inflammatory bowel disease.

    PubMed

    Malayandi, Rajkumar; Kondamudi, Phani Krishna; Ruby, P K; Aggarwal, Deepika

    2014-04-01

    Colon targeted dosage forms have been extensively studied for the localized treatment of inflammatory bowel disease. These dosage forms not only improve the therapeutic efficacy but also reduce the incidence of adverse drug reactions and hence improve the patient compliance. However, complex and highly variable gastro intestinal physiology limits the clinical success of these dosage forms. Biopharmaceutical characteristics of these dosage forms play a key role in rapid formulation development and ensure the clinical success. The complexity in product development and clinical success of colon targeted dosage forms are based on the biopharmaceutical characteristics such as physicochemical properties of drug substances, pharmaceutical characteristics of dosage form, physiological conditions and pharmacokinetic properties of drug substances as well as drug products. Various in vitro and in vivo techniques have been employed in past to characterize the biopharmaceutical properties of colon targeted dosage forms. This review focuses on the factors influencing the biopharmaceutical performances of the dosage forms, in vitro characterization techniques and in vivo studies.

  20. Preformulation considerations for controlled release dosage forms. Part I. Selecting candidates.

    PubMed

    Chrzanowski, Frank

    2008-01-01

    The physical-chemical properties of interest for controlled release (CR) dosage form development presented are based on the author's experience. Part I addresses selection of the final form based on a logical progression of physical-chemical properties evaluation of candidate forms and elimination of forms with undesirable properties from further evaluation in order to simplify final form selection. Several candidate forms which could include salt, free base or acid, polymorphic and amorphic forms of a new chemical entity (NCE) or existing drug substance (DS) are prepared and evaluated for critical properties in a scheme relevant to manufacturing processes, predictive of problems, requiring small amounts of test materials and simple analytical tools. A stability indicating assay is not needed to initiate the evaluation. This process is applicable to CR and immediate release (IR) dosage form development. The critical properties evaluated are melting, crystallinity, solubilities in water, 0.1 N HCl, and SIF, hygrodymamics, i.e., moisture sorption and loss at extremes of RH, and LOD at typical wet granulation drying conditions, and processability, i.e., corrosivity, and filming and/or sticking upon compression.

  1. New sensitive kinetic spectrophotometric methods for determination of omeprazole in dosage forms.

    PubMed

    Mahmoud, Ashraf M

    2009-01-01

    New rapid, sensitive, and accurate kinetic spectrophotometric methods were developed, for the first time, to determine omeprazole (OMZ) in its dosage forms. The methods were based on the formation of charge-transfer complexes with both iodine and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). The variables that affected the reactions were carefully studied and optimized. The formed complexes and the site of interaction were examined by UV/VIS, IR, and (1)H-NMR techniques, and computational molecular modeling. Under optimum conditions, the stoichiometry of the reactions between OMZ and the acceptors was found to be 1 : 1. The order of the reactions and the specific rate constants were determined. The thermodynamics of the complexes were computed and the mechanism of the reactions was postulated. The initial rate and fixed time methods were utilized for the determination of OMZ concentrations. The linear ranges for the proposed methods were 0.10-3.00 and 0.50-25.00 mug mL(-1) with the lowest LOD of 0.03 and 0.14 mug mL(-1) for iodine and DDQ, respectively. Analytical performance of the methods was statistically validated; RSD was <1.25% for the precision and <1.95% for the accuracy. The proposed methods were successfully applied to the analysis of OMZ in its dosage forms; the recovery was 98.91-100.32% +/- 0.94-1.84, and was found to be comparable with that of reference method.

  2. A progressive review of Sandhana kalpana (Biomedical fermentation): An advanced innovative dosage form of Ayurveda

    PubMed Central

    Chaudhary, Anand; Singh, Neetu; Dalvi, Madhuri; Wele, Asmita

    2011-01-01

    Sandhana kalpana (biomedical fermented formulations) are one of the best dosage forms of Ayurveda in practice since thousands of years. In order to prepare these medicaments, certain sets of conditions are prearranged, which lead to fermentation. Thus, products bequeath with self-generated ethyl alcohol, which potentiate these preparations (Asava–Arishta), pharmaceutically and therapeutically. Commonly, medicinal and commercial components of these formulations are prompting many researchers to contribute in manufacturing, quality control, safety, and efficacy of these formulations. To cope up with this, literature related to Asava–Arishta has been surveyed from the Vedic period to recent publications of Government of India, ie, Ayurvedic Formulary of India, and presented briefly here. In this review paper, we have discussed pioneering facts such as nature and amount of carbohydrate, type of containers, optimum temperature, variety and relevance of initiator of fermentation, manufacturing, regulatory rules, and business aspects of Asava-Arishta. After going through this basic information, any academician or researcher may show a way to further strengthen this dosage form. PMID:22529661

  3. The X factor: X chromosome dosage compensation in the evolutionarily divergent monotremes and marsupials.

    PubMed

    Whitworth, Deanne J; Pask, Andrew J

    2016-08-01

    Marsupials and monotremes represent evolutionarily divergent lineages from the majority of extant mammals which are eutherian, or placental, mammals. Monotremes possess multiple X and Y chromosomes that appear to have arisen independently of eutherian and marsupial sex chromosomes. Dosage compensation of X-linked genes occurs in monotremes on a gene-by-gene basis, rather than through chromosome-wide silencing, as is the case in eutherians and marsupials. Specifically, studies in the platypus have shown that for any given X-linked gene, a specific proportion of nuclei within a cell population will silence one locus, with the percentage of cells undergoing inactivation at that locus being highly gene-specific. Hence, it is perhaps not surprising that the expression level of X-linked genes in female platypus is almost double that in males. This is in contrast to the situation in marsupials where one of the two X chromosomes is inactivated in females by the long non-coding RNA RSX, a functional analogue of the eutherian XIST. However, marsupial X chromosome inactivation differs from that seen in eutherians in that it is exclusively the paternal X chromosome that is silenced. In addition, marsupials appear to have globally upregulated X-linked gene expression in both sexes, thus balancing their expression levels with those of the autosomes, a process initially proposed by Ohno in 1967 as being a fundamental component of the X chromosome dosage compensation mechanism but which may not have evolved in eutherians.

  4. Antioxidant activity evaluation of new dosage forms as vehicles for dehydrated vegetables.

    PubMed

    Romero-de Soto, María Dolores; García-Salas, Patricia; Fernández-Arroyo, Salvador; Segura-Carretero, Antonio; Fernández-Campos, Francisco; Clares-Naveros, Beatriz

    2013-06-01

    A dehydrated vegetables mixture loaded in four pharmaceutical dosage forms as powder, effervescent granulate, sugar granulate and gumdrops were investigated for their antioxidant capacity using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging capacity assay, oxygen radical absorbance capacity assay and ferric reducing antioxidant potential assay. Total phenolic content of dehydrated vegetables powder mixture was also measured by the Folin-Ciocalteu method, so as to evaluate its contribution to their total antioxidant function. The effect of different temperatures on stability of these systems after 90 days storage was also evaluated. These formulations presented strong antioxidant properties and high phenolic content (279 mg gallic acid equivalent/g of sample) and thus could be potential rich sources of natural antioxidants. Antioxidant properties differed significantly among selected formulations (p < 0.05). Generally, the losses were lower in samples stored under refrigeration. To interpret the antioxidant properties a kinetic approach was performed. Degradation kinetics for the phenolic content and antioxidant capacity followed a zero-order function. Effervescent granulate was the formulation which underwent faster degradation. Contrary, sugar granulate and gumdrops were much more slowly. Time required to halve the initial amount of phenolic compounds was 589 ± 45 days for samples stored at 4 º C, and 312 ± 16 days for samples stored at room temperature. These developed dosage forms are new and innovative approach for vegetable intakes in population with special requirements providing an improvement in the administration of vegetables and fruits.

  5. Milestone Report - Complete New Adsorbent Materials for Marine Testing to Demonstrate 4.5 g-U/kg Adsorbent

    SciTech Connect

    Janke, Christopher James; Das, Sadananda; Oyola, Yatsandra; Mayes, Richard T.; Saito, Tomonori; Brown, Suree; Gill, Gary; Kuo, Li-Jung; Wood, Jordana

    2014-08-01

    This report describes work on the successful completion of Milestone M2FT-14OR03100115 (8/20/2014) entitled, “Complete new adsorbent materials for marine testing to demonstrate 4.5 g-U/kg adsorbent”. This effort is part of the Seawater Uranium Recovery Program, sponsored by the U.S. Department of Energy, Office of Nuclear Energy, and involved the development of new adsorbent materials at the Oak Ridge National Laboratory (ORNL) and marine testing at the Pacific Northwest National Laboratory (PNNL). ORNL has recently developed two new families of fiber adsorbents that have demonstrated uranium adsorption capacities greater than 4.5 g-U/kg adsorbent after marine testing at PNNL. One adsorbent was synthesized by radiation-induced graft polymerization of itaconic acid and acrylonitrile onto high surface area polyethylene fibers followed by amidoximation and base conditioning. This fiber showed a capacity of 4.6 g-U/kg adsorbent in marine testing at PNNL. The second adsorbent was prepared by atom-transfer radical polymerization of t-butyl acrylate and acrylonitrile onto halide-functionalized round fibers followed by amidoximation and base hydrolysis. This fiber demonstrated uranium adsorption capacity of 5.4 g-U/kg adsorbent in marine testing at PNNL.

  6. Sweet potato starch residue as starting material to prepare polyacrylonitrile adsorbent via SI-SET-LRP.

    PubMed

    Hao, Zhihai; Wang, Dongju; Chen, Hou; Sun, Jinming; Xu, Yuanyuan

    2014-02-26

    Sweet potato starch residue (SPSR) was used as starting material to prepare an eco-friendly adsorbent. SPSR was modified by bromoacetyl bromide to obtain a macroinitiator for surface-initiated single electron transfer-living radical polymerization (SI-SET-LRP) of acrylonitrile (AN) catalyzed by La(0)/hexamethylenetetramine (HMTA) in N,N-dimethylformamide (DMF) in the presence of ascorbic acid (VC). The amidoxime (AO) adsorbent was prepared by the reaction of the graft copolymer bromoactylated sweet potato starch (BSPS)/polyacrylonitrile (BSPS-g-PAN) with hydroxylamine. The maximum adsorption capacity for Hg(II) was 4.03 mmol·g(-1). This simple method provided a novel approach to recycle and reuse agricultural residues for controlling heavy metal pollution.

  7. Study of the behaviour of thorium adsorption on PAN/zeolite composite adsorbent.

    PubMed

    Kaygun, A Kilincarslan; Akyil, S

    2007-08-17

    The adsorption behaviour of thorium from aqueous solutions by a composite adsorbent has been investigated by a batch technique. The thorium adsorption on composite adsorbent was studied as a function of initial concentration, pH, shaking time and temperature. The sorption of thorium at the determined optimum conditions follows Langmuir, Freundlich and D-R type isotherms. Langmuir constants Q=0.04 mmol g(-1) and b=64.94 L mol(-1) and of D-R parameter Xm = 0.04, beta=0.79 and of sorption energy E=0.80 and Freundlich constants 1/n=3.12 and cm = 0.012 mmol g(-1) were evaluated. Thermodynamic parameters such as DeltaH and DeltaS were found to be 37.32 kJ mol(-1) and 206.17 J mol(-1)K(-1), respectively.

  8. Influence of adsorbed fluids on the rolling contact deformation of MgO single crystals

    NASA Technical Reports Server (NTRS)

    Dufrane, K. F.

    1977-01-01

    Basic phenomena associated with rolling contact deformation were studied using MgO as a model bearing material. A hardened steel ball was rolled on MgO single crystals in slow-speed reciprocating motion and in high-speed circular motion. The resulting deformation was studied by dislocation etch-pit techniques. The presence of adsorbed fluids, such as silicone oil, white mineral oil, and toluene, with slow-speed sliding caused a dramatic change in slip mode and premature surface spalling compared with similar experiments in air or under water. In contrast, dimethyl formamide inhibited these slip processes. The results are consistent with the dependence of dislocation mobility on adsorbed species. High-speed hydrodynamic rolling with mineral oil lubrication produced a different slip phenomena entirely from the slow-speed rolling. The slip bands resembled those produced in tensile tests, and all slip apparently initiated at subsurface sites.

  9. Currently used dosage regimens of vancomycin fail to achieve therapeutic levels in approximately 40% of intensive care unit patients

    PubMed Central

    Obara, Vitor Yuzo; Zacas, Carolina Petrus; Carrilho, Claudia Maria Dantas de Maio; Delfino, Vinicius Daher Alvares

    2016-01-01

    Objective This study aimed to assess whether currently used dosages of vancomycin for treatment of serious gram-positive bacterial infections in intensive care unit patients provided initial therapeutic vancomycin trough levels and to examine possible factors associated with the presence of adequate initial vancomycin trough levels in these patients. Methods A prospective descriptive study with convenience sampling was performed. Nursing note and medical record data were collected from September 2013 to July 2014 for patients who met inclusion criteria. Eighty-three patients were included. Initial vancomycin trough levels were obtained immediately before vancomycin fourth dose. Acute kidney injury was defined as an increase of at least 0.3mg/dL in serum creatinine within 48 hours. Results Considering vancomycin trough levels recommended for serious gram-positive infection treatment (15 - 20µg/mL), patients were categorized as presenting with low, adequate, and high vancomycin trough levels (35 [42.2%], 18 [21.7%], and 30 [36.1%] patients, respectively). Acute kidney injury patients had significantly greater vancomycin trough levels (p = 0.0055, with significance for a trend, p = 0.0023). Conclusion Surprisingly, more than 40% of the patients did not reach an effective initial vancomycin trough level. Studies on pharmacokinetic and dosage regimens of vancomycin in intensive care unit patients are necessary to circumvent this high proportion of failures to obtain adequate initial vancomycin trough levels. Vancomycin use without trough serum level monitoring in critically ill patients should be discouraged. PMID:28099635

  10. Feasibility of fullerene waste as carbonaceous adsorbent

    SciTech Connect

    Cleveland, T.G.; Garg, S.; Rixey, W.G.

    1996-03-01

    This note investigates using the waste soot generated in fullerene manufacture as an adsorbent. Both oven-dried and air-activated samples of waste soot are compared with three commercially available powdered activated carbons (PACs): Nuchar-SA, HDH, and Calgon-RC. Three model compounds were chosen for adsorption tests--TCE, Benzene, and Phenol--representing a small branched molecule, a small nonpolar ring molecule, and relatively polar ring molecule. Additionally, the effectiveness of total organic carbon (TOC) removal from wastewater was evaluated. Oven-dried soot performed poorly as compared to the commercial carbons, but activation of the waste soot for 60 min at 450 C in air resulted in an activated carbon (aFWS) with properties similar to those of commercially available PACs. The aFWS performed better than one would predict from the typical characterization measures of iodine number, molasses number, and methylene blue number. The data for phenol suggest some functional groups are created during the activation of the waste soot. These results show that large-scale fullerene manufacturing can be a zero-waste industry, because its primary waste product can be converted into a useful material.

  11. Photoreduction of methylviologen adsorbed on silver

    SciTech Connect

    Feilchenfeld, H.; Chumanov, G.; Cotton, T.M. |

    1996-03-21

    Methylviologen adsorbed on a roughened silver electrode is reduced to its cation radical upon irradiation with laser light at liquid nitrogen temperature. Surface-enhanced Raman scattering (SERS) spectra were obtained with different excitation wavelengths between 406 and 752 nm and compared to those obtained at room temperature in an electrochemical cell under potential control. From two-color experiments, in which one laser frequency was used to generate the radical and a second to excite the SERS spectra, it was determined that radical formation occurs mainly with excitation in the blue spectral region. A comparison of the SERS spectra of the dication and cation radical forms of methylviologen with their solution spectra suggests that the former interacts more strongly with the surface than the latter. The cation radical appears to be stable for several hours in liquid nitrogen but has a short lifetime at room temperature. Two mechanisms for the photoreduction are discussed: plasmon-assisted electron transfer from the metal to the methylviologen dication and formation of a resonance charge transfer complex. The current experimental data are insufficient to determine the particular role of these mechanisms. 23 refs., 9 figs.

  12. NASA Applications of Molecular Adsorber Coatings

    NASA Technical Reports Server (NTRS)

    Abraham, Nithin S.

    2015-01-01

    The Molecular Adsorber Coating (MAC) is a new, innovative technology that was developed to reduce the risk of molecular contamination on spaceflight applications. Outgassing from materials, such as plastics, adhesives, lubricants, silicones, epoxies, and potting compounds, pose a significant threat to the spacecraft and the lifetime of missions. As a coating made of highly porous inorganic materials, MAC offers impressive adsorptive capabilities that help capture and trap contaminants. Past research efforts have demonstrated the coating's promising adhesion performance, optical properties, acoustic durability, and thermal stability. These results advocate its use near or on surfaces that are targeted by outgassed materials, such as internal optics, electronics, detectors, baffles, sensitive instruments, thermal control coatings, and vacuum chamber test environments. The MAC technology has significantly progressed in development over the recent years. This presentation summarizes the many NASA spaceflight applications of MAC and how the coatings technology has been integrated as a mitigation tool for outgassed contaminants. For example, this sprayable paint technology has been beneficial for use in various vacuum chambers for contamination control and hardware bake-outs. The coating has also been used in small instrument cavities within spaceflight instrument for NASA missions.

  13. DBPs removal in GAC filter-adsorber.

    PubMed

    Kim, Jinkeun; Kang, Byeongsoo

    2008-01-01

    A rapid sand filter and granular activated carbon filter-adsorber (GAC FA) were compared in terms of dissolved organic carbon (DOC) and disinfection by-products (DBPs) removal. A water treatment plant (WTP) that had a high ammonia concentration and DOC in raw water, which, in turn, led to a high concentration of DBPs because of a high dose of pre-chlorination, was investigated. To remove DBPs and DOC simultaneously, a conventional rapid sand filter had been retrofitted to a GAC FA at the Buyeo WTP in Korea. The overall removal efficiency of DBPs and DOC was higher in the GAC FA than in the sand filter, as expected. Breakthrough of trihalomethanes (THMs) was noticed after 3 months of GAC FA operation, and then removal of THMs was minimal (<10%). On the other hand, the removal efficiency of five haloacetic acids (HAA(5)) in the GAC FA was better than that of THMs, though adsorption of HAA(5) decreased rapidly after 3.5 months of GAC FA operation. And then, gradual improvement (>90%) in HAA(5) removal efficiency was again observed, which could be attributed to biodegradation. At the early stage of GAC FA operation, HAA(5) removal was largely due to physical adsorption, but later on biodegradation appeared to prevail. Biodegradation of HAA(5) was significantly influenced by water temperature. Similar turbidity removal was noticed in both filters, while better manganese removal was confirmed in the sand filter rather than in the GAC FA.

  14. Imaging the wave functions of adsorbed molecules.

    PubMed

    Lüftner, Daniel; Ules, Thomas; Reinisch, Eva Maria; Koller, Georg; Soubatch, Serguei; Tautz, F Stefan; Ramsey, Michael G; Puschnig, Peter

    2014-01-14

    The basis for a quantum-mechanical description of matter is electron wave functions. For atoms and molecules, their spatial distributions and phases are known as orbitals. Although orbitals are very powerful concepts, experimentally only the electron densities and -energy levels are directly observable. Regardless whether orbitals are observed in real space with scanning probe experiments, or in reciprocal space by photoemission, the phase information of the orbital is lost. Here, we show that the experimental momentum maps of angle-resolved photoemission from molecular orbitals can be transformed to real-space orbitals via an iterative procedure which also retrieves the lost phase information. This is demonstrated with images obtained of a number of orbitals of the molecules pentacene (C22H14) and perylene-3,4,9,10-tetracarboxylic dianhydride (C24H8O6), adsorbed on silver, which are in excellent agreement with ab initio calculations. The procedure requires no a priori knowledge of the orbitals and is shown to be simple and robust.

  15. 21 CFR 520.1263 - Lincomycin hydrochloride monohydrate oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Lincomycin hydrochloride monohydrate oral dosage... HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1263 Lincomycin hydrochloride monohydrate oral dosage forms....

  16. 21 CFR 520.1326 - Mebendazole and trichlorfon oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Mebendazole and trichlorfon oral dosage forms. 520... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1326 Mebendazole and trichlorfon oral dosage forms....

  17. 21 CFR 524.390 - Chloramphenicol ophthalmic and topical dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Chloramphenicol ophthalmic and topical dosage... HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS § 524.390 Chloramphenicol ophthalmic and topical dosage forms....

  18. 21 CFR 520.2158 - Streptomycin/dihydrostreptomycin oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Streptomycin/dihydrostreptomycin oral dosage forms... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2158 Streptomycin/dihydrostreptomycin oral dosage forms....

  19. 21 CFR 522.1696 - Penicillin G procaine implantation and injectable dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Penicillin G procaine implantation and injectable dosage forms. 522.1696 Section 522.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... DOSAGE FORM NEW ANIMAL DRUGS § 522.1696 Penicillin G procaine implantation and injectable dosage forms....

  20. 21 CFR 522.1696 - Penicillin G procaine implantation and injectable dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin G procaine implantation and injectable dosage forms. 522.1696 Section 522.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... DOSAGE FORM NEW ANIMAL DRUGS § 522.1696 Penicillin G procaine implantation and injectable dosage forms....

  1. 21 CFR 522.1696 - Penicillin G procaine implantation and injectable dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Penicillin G procaine implantation and injectable dosage forms. 522.1696 Section 522.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... DOSAGE FORM NEW ANIMAL DRUGS § 522.1696 Penicillin G procaine implantation and injectable dosage forms....

  2. 21 CFR 522.1696 - Penicillin G procaine implantation and injectable dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Penicillin G procaine implantation and injectable dosage forms. 522.1696 Section 522.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... DOSAGE FORM NEW ANIMAL DRUGS § 522.1696 Penicillin G procaine implantation and injectable dosage forms....

  3. 21 CFR 330.3 - Imprinting of solid oral dosage form drug products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Imprinting of solid oral dosage form drug products... AS SAFE AND EFFECTIVE AND NOT MISBRANDED General Provisions § 330.3 Imprinting of solid oral dosage form drug products. A requirement to imprint an identification code on solid oral dosage form...

  4. 21 CFR 330.3 - Imprinting of solid oral dosage form drug products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Imprinting of solid oral dosage form drug products... AS SAFE AND EFFECTIVE AND NOT MISBRANDED General Provisions § 330.3 Imprinting of solid oral dosage form drug products. A requirement to imprint an identification code on solid oral dosage form...

  5. The Development of Teaching Efficacy for Drug-Dosage Calculation Instruction: A Nursing Faculty Perspective

    ERIC Educational Resources Information Center

    Vitale, Gail A.

    2011-01-01

    The purpose of this study was to examine how nursing efficacy for drug-dosage calculation instruction is determined. Medication administration is a critical function of nurses in healthcare settings. An essential component of safe medication administration is accurate drug-dosage calculation, but instruction in drug-dosage calculation methods…

  6. 21 CFR 522.960 - Flumethasone implantation or injectable dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Flumethasone implantation or injectable dosage... HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.960 Flumethasone implantation or injectable dosage forms....

  7. 21 CFR 522.960 - Flumethasone implantation or injectable dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Flumethasone implantation or injectable dosage... HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.960 Flumethasone implantation or injectable dosage forms....

  8. 21 CFR 522.960 - Flumethasone implantation or injectable dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Flumethasone implantation or injectable dosage... HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.960 Flumethasone implantation or injectable dosage forms....

  9. 21 CFR 522.960 - Flumethasone implantation or injectable dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Flumethasone implantation or injectable dosage... HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.960 Flumethasone implantation or injectable dosage forms....

  10. Surfactant-modified montmorillonite as a nanosized adsorbent for removal of an insecticide: kinetic and isotherm studies.

    PubMed

    Hassani, Aydin; Khataee, Alireza; Karaca, Semra; Shirzad-Siboni, Mehdi

    2015-01-01

    Surfactant-modified montmorillonites (MMT) were prepared using trimethyloctylammonium bromide (TMOAB) and employed as a nanosized adsorbent to remove diazinon from aqueous solutions. The prepared adsorbent was characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX). The dependence of removal efficiency on initial diazinon concentration, amount of adsorbent, pH of the solution and ionic strength was investigated. The affinity sequence for ion adsorption on TMOAB/MMT was in the order: without anion> sodium carbonate> sodium bicarbonate> sodium sulphate> sodium chloride. The adsorption kinetic and isotherm were best fit by a pseudo-second-order kinetic and Langmuir isotherm models, respectively.

  11. Process development for the removal and recovery of hazardous dye erythrosine from wastewater by waste materials-Bottom Ash and De-Oiled Soya as adsorbents.

    PubMed

    Mittal, Alok; Mittal, Jyoti; Kurup, Lisha; Singh, A K

    2006-11-02

    Erythrosine is a water-soluble xanthene class of dye. It is widely used as colorant in foods, textiles, drugs and cosmetics. It is highly toxic, causes various types of allergies, thyroid activities, carcinogenicity, DNA damage behaviour, neurotoxicity and xenoestrogen nature in the humans and animals. The photochemical and biochemical degradation of the erythrosine is not recommended due to formation of toxic by-products. The present paper is an attempt to remove erythrosine from wastewater using adsorption over Bottom Ash-a power plant waste and De-Oiled Soya-an agricultural waste. Under the batch studies, effect of concentration of dye, temperature, pH of the solution, dosage of adsorbents, sieve size of adsorbents, etc., have been studied for the uptake of the dye over both adsorbents. The adsorption process verifies Langmuir and Freundlich adsorption isotherms in both the cases and based on the data different thermodynamic parameters have been evaluated. Batch studies also include kinetic measurements, rate constant study, mass transfer behaviour and establishment of mechanistic pathway for both the cases. For the bulk removal of the dye column operations have been carried out and breakthrough capacities of the Bottom Ash and De-Oiled Soya columns have been calculated. Attempts have also been made for the recovery of the adsorbed dye from exhausted columns by eluting dilute NaOH and more than 90% of the dye was recovered.

  12. Application of carbon adsorbents prepared from Brazilian-pine fruit shell for the removal of reactive orange 16 from aqueous solution: Kinetic, equilibrium, and thermodynamic studies.

    PubMed

    Calvete, Tatiana; Lima, Eder C; Cardoso, Natali F; Vaghetti, Júlio C P; Dias, Silvio L P; Pavan, Flavio A

    2010-08-01

    Activated (AC-PW) and non-activated (C-PW) carbonaceous materials were prepared from the Brazilian-pine fruit shell (Araucaria angustifolia) and tested as adsorbents for the removal of reactive orange 16 dye (RO-16) from aqueous effluents. The effects of shaking time, adsorbent dosage and pH on the adsorption capacity were studied. RO-16 uptake was favorable at pH values ranging from 2.0 to 3.0 and from 2.0 to 7.0 for C-PW and AC-PW, respectively. The contact time required to obtain the equilibrium using C-PW and AC-PW as adsorbents was 5 and 4h at 298 K, respectively. The fractionary-order kinetic model provided the best fit to experimental data compared with other models. Equilibrium data were better fit to the Sips isotherm model using C-PW and AC-PW as adsorbents. The enthalpy and entropy of adsorption of RO-16 were obtained from adsorption experiments ranging from 298 to 323 K.

  13. Use of waste materials--Bottom Ash and De-Oiled Soya, as potential adsorbents for the removal of Amaranth from aqueous solutions.

    PubMed

    Mittal, Alok; Kurup Krishnan, Lisha; Gupta, Vinod K

    2005-01-31

    Bottom Ash, a power plan t waste material and De-Oiled Soya, an agriculture waste product were successfully utilized in removing trisodium 2-hydroxy-1-(4-sulphonato-1-naphthylazo)naphthalene-3,6-disulphonate--a water-soluble hazardous azo dye (Amaranth). The paper incorporates thermodynamic and kinetic studies for the adsorption of the dye on these two waste materials as adsorbents. Characterization of each adsorbent was carried out by I.R. and D.T.A. curves. Batch adsorption studies were made by measuring effects of pH, adsorbate concentration, sieve size, adsorbent dosage, contact time, temperature etc. Specific rate constants for the processes were calculated by kinetic measurements and a first order adsorption kinetics was observed in each case. Langmuir and Freundlich adsorption isotherms were applied to calculate thermodynamic parameters. The adsorption on Bottom Ash takes place via film diffusion process at lower concentrations and via particle diffusion process at higher concentrations, while in the case of De-Oiled Soya process only particle diffusion takes place in the entire concentration range.

  14. Development of carbon dioxide adsorbent from rice husk char

    NASA Astrophysics Data System (ADS)

    Abang, S.; Janaun, J.; Anisuzzaman, S. M.; Ikhwan, F. S.

    2016-06-01

    This study was mainly concerned about the development of carbon dioxide (CO2) adsorbent from rice husk (RH). Several chemical treatments were used to produce activated rice husk char (RHAC) from RH. Initially the RH was refluxed with 3M of sodium hydroxide (NaOH) solution, activation followed by using 0.5M of zinc chloride (ZnCl2) solution and finally acidic treatment by using 0.1M of hydrochloric acid (HCl). Then, the RHAC was functionalized by using 3-chloropropylamine hydrochloride (3-CPA) and noted as RHN. RHN samples were characterized with scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP), fourier transform infrared spectroscopy (FTIR). Based on the SEM, the RHN sample had a large pore diameter compared to RH sample after being treated. Based on MIP data, the average pore diameter between RH and RHAC samples were increased significantly from 0.928 microns to 1.017 microns. The RHN sample also had higher total porosity (%) compared to RHAC and RH (58.45%, 47.82% and 45.57% respectively). The total specific surface area of the sample was much increasing from RHO to RHAC (29.17 m2/g and 62.94 m2/g respectively) and slightly being decreasing from RHAC to RHN (58.88 m2/g). FTIR result showed the present of weak band at 1587 cm-1 which demonstrating of the amine group present on the sample. The CO2 capture result showed that the decreasing of operating temperature can increase the breakthrough time of CO2 capture. On the contrary decreasing of CO2 gas flow rate can increase the breakthrough time of CO2 capture. The highest total amount of CO2 adsorbed was 25338.57 mg of CO2/g of RHN sample by using 100 mL/min of gas flow rate at 30oC. Based on adsorption isotherm analysis, the Freundlich isotherm was the best isotherm to describe the CO2 adsorption on the sample.

  15. 76 FR 63304 - Guidance for Industry on Incorporation of Physical-Chemical Identifiers Into Solid Oral Dosage...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-12

    ... Solid Oral Dosage Form Drug Products for Anticounterfeiting; Availability AGENCY: Food and Drug... Oral Dosage Form Drug Products for Anticounterfeiting.'' This guidance provides recommendations on... Identifiers Into Solid Oral Dosage Form Drug Products for Anticounterfeiting.'' For the purpose of...

  16. Carbon dioxide pressure swing adsorption process using modified alumina adsorbents

    DOEpatents

    Gaffney, T.R.; Golden, T.C.; Mayorga, S.G.; Brzozowski, J.R.; Taylor, F.W.

    1999-06-29

    A pressure swing adsorption process for absorbing CO[sub 2] from a gaseous mixture containing CO[sub 2] comprises introducing the gaseous mixture at a first pressure into a reactor containing a modified alumina adsorbent maintained at a temperature ranging from 100 C and 500 C to adsorb CO[sub 2] to provide a CO[sub 2] laden alumina adsorbent and a CO[sub 2] depleted gaseous mixture and contacting the CO[sub 2] laden adsorbent with a weakly adsorbing purge fluid at a second pressure which is lower than the first pressure to desorb CO[sub 2] from the CO[sub 2] laden alumina adsorbent. The modified alumina adsorbent which is formed by depositing a solution having a pH of 3.0 or more onto alumina and heating the alumina to a temperature ranging from 100 C and 600 C, is not degraded by high concentrations of water under process operating conditions. 1 fig.

  17. Carbon dioxide pressure swing adsorption process using modified alumina adsorbents

    DOEpatents

    Gaffney, Thomas Richard; Golden, Timothy Christopher; Mayorga, Steven Gerard; Brzozowski, Jeffrey Richard; Taylor, Fred William

    1999-01-01

    A pressure swing adsorption process for absorbing CO.sub.2 from a gaseous mixture containing CO.sub.2 comprising introducing the gaseous mixture at a first pressure into a reactor containing a modified alumina adsorbent maintained at a temperature ranging from 100.degree. C. and 500.degree. C. to adsorb CO.sub.2 to provide a CO.sub.2 laden alumina adsorbent and a CO.sub.2 depleted gaseous mixture and contacting the CO.sub.2 laden adsorbent with a weakly adsorbing purge fluid at a second pressure which is lower than the first pressure to desorb CO.sub.2 from the CO.sub.2 laden alumina adsorbent. The modified alumina adsorbent which is formed by depositing a solution having a pH of 3.0 or more onto alumina and heating the alumina to a temperature ranging from 100.degree. C. and 600.degree. C., is not degraded by high concentrations of water under process operating conditions.

  18. Methane Recovery from Gaseous Mixtures Using Carbonaceous Adsorbents

    NASA Astrophysics Data System (ADS)

    Buczek, Bronisław

    2016-06-01

    Methane recovery from gaseous mixtures has both economical and ecological aspect. Methane from different waste gases like mine gases, nitrogenated natural gases and biogases can be treated as local source for production electric and heat energy. Also occurs the problem of atmosphere pollution with methane that shows over 20 times more harmful environmental effect in comparison to carbon dioxide. One of the ways utilisation such gases is enrichment of methane in the PSA technique, which requires appropriate adsorbents. Active carbons and carbon molecular sieve produced by industry and obtained in laboratory scale were examined as adsorbent for methane recuperation. Porous structure of adsorbents was investigated using densimetry measurements and adsorption of argon at 77.5K. On the basis of adsorption data, the Dubinin-Radushkevich equation parameters, micropore volume (Wo) and characteristics of energy adsorption (Eo) as well as area micropores (Smi) and BET area (SBET) were determined. The usability of adsorbents in enrichment of the methane was evaluated in the test, which simulate the basic stages of PSA process: a) adsorbent degassing, b) pressure raise in column by feed gas, c) cocurrent desorption with analysis of out flowing gas. The composition of gas phase was accepted as the criterion of the suitability of adsorbent for methane separation from gaseous mixtures. The relationship between methane recovery from gas mixture and texture parameters of adsorbents was found.

  19. Mercury adsorption properties of sulfur-impregnated adsorbents

    USGS Publications Warehouse

    Hsi, N.-C.; Rood, M.J.; Rostam-Abadi, M.; Chen, S.; Chang, R.

    2002-01-01

    Carbonaceous and noncarbonaceous adsorbents were impregnated with elemental sulfur to evaluate the chemical and physical properties of the adsorbents and their equilibrium mercury adsorption capacities. Simulated coal combustion flue gas conditions were used to determine the equilibrium adsorption capacities for Hg0 and HgCl2 gases to better understand how to remove mercury from gas streams generated by coal-fired utility power plants. Sulfur was deposited onto the adsorbents by monolayer surface deposition or volume pore filling. Sulfur impregnation increased the total sulfur content and decreased the total and micropore surface areas and pore volumes for all of the adsorbents tested. Adsorbents with sufficient amounts of active adsorption sites and sufficient microporous structure had mercury adsorption capacities up to 4,509 ??g Hg/g adsorbent. Elemental sulfur, organic sulfur, and sulfate were formed on the adsorbents during sulfur impregnation. Correlations were established with R2>0.92 between the equilibrium Hg0/HgCl2 adsorption capacities and the mass concentrations of elemental and organic sulfur. This result indicates that elemental and organic sulfur are important active adsorption sites for Hg0 and HgCl2.

  20. Removal of arsenic(III) and arsenic(V) on chemically modified low-cost adsorbent: batch and column operations

    NASA Astrophysics Data System (ADS)

    Roy, Palas; Mondal, Naba Kumar; Bhattacharya, Shreya; Das, Biswajit; Das, Kousik

    2013-03-01

    Batch and column operations were performed utilizing thioglycolated sugarcane carbon (TSCC), a low-cost adsorbent, to remove As(III) and As(V) from aqueous systems. Under optimized batch conditions, the TSCC could remove up to 92.7 and 91.4 % for As(III) and As(V), respectively. An artificial neural network model showed the validity of TSCC as a preferable adsorbent for arsenic [As(III) and As(V)] removal in batch studies. In column operations, removal efficiency increases with increase in influent arsenic concentration and adsorbent dose and decreases with increase in flow rate. At an adsorbent dose of 6.0 g, flow rate 3.0 mL min-1, and initial arsenic concentration 1,500 μg L-1, the arsenic uptake capacity of TSCC for As(III) and As(V) was found to be 85.01 and 83.82 μg g-1, respectively. The Thomas model was used to analyze the column experimental data. Results from the column operations indicated that the adsorption behavior of arsenic [As(III) and As(V)] fits exceptionally well with the Thomas model with high correlation coefficient and very low standard error. Examinations of scanning electron microscopy and FTIR spectroscopy reveal that high arsenic adsorption favors surface complexation on the adsorbent surface.

  1. Rapid enrichment of rare-earth metals by carboxymethyl cellulose-based open-cellular hydrogel adsorbent from HIPEs template.

    PubMed

    Zhu, Yongfeng; Wang, Wenbo; Zheng, Yian; Wang, Feng; Wang, Aiqin

    2016-04-20

    A series of monolithic open-cellular hydrogel adsorbents based on carboxymethylcellulose (CMC) were prepared through high internal phase emulsions (HIPEs) and used to enrich the rare-earth metals La(3+) and Ce(3+). The changes of pore structure, and the effects of pH, contact time, initial concentration on the adsorption performance were systematically studied. The results show that the as-prepared monolithic hydrogel adsorbents possess good open-cellular framework structure and have fast adsorption kinetics and high adsorption capacity for La(3+) and Ce(3+). The involved adsorption system can reach equilibrium within 30min and the maximal adsorption capacity is determined to be 384.62mg/g for La(3+) and 333.33mg/g for Ce(3+). Moreover, these porous hydrogel adsorbents show an excellent adsorptive reusability for La(3+) and Ce(3+) through five adsorption-desorption cycles. Such a pore hierarchy structure makes this monolithic open-cellular hydrogel adsorbent be an effective adsorbent for effective enrichment of La(3+) and Ce(3+) from aqueous solution.

  2. Novel adhesive properties of poly(ethylene-oxide) adsorbed nanolayers

    NASA Astrophysics Data System (ADS)

    Zeng, Wenduo

    Solid-polymer interfaces play crucial roles in the multidisciplinary field of nanotechnology and are the confluence of physics, chemistry, biology, and engineering. There is now growing evidence that polymer chains irreversibly adsorb even onto weakly attractive solid surfaces, forming a nanometer-thick adsorbed polymer layer ("adsorbed polymer nanolayers"). It has also been reported that the adsorbed layers greatly impact on local structures and properties of supported polymer thin films. In this thesis, I aim to clarify adhesive and tribological properties of adsorbed poly(ethylene-oxide) (PEO) nanolayers onto silicon (Si) substrates, which remain unsolved so far. The adsorbed nanolayers were prepared by the established protocol: one has to equilibrate the melt or dense solution against a solid surface; the unadsorbed chains can be then removed by a good solvent, while the adsorbed chains are assumed to maintain the same conformation due to the irreversible freezing through many physical solid-segment contacts. I firstly characterized the formation process and the surface/film structures of the adsorbed nanolayers by using X-ray reflectivity, grazing incidence X-ray diffraction, and atomic force microscopy. Secondly, to compare the surface energy of the adsorbed layers with the bulk, static contact angle measurements with two liquids (water and glycerol) were carried out using a optical contact angle meter equipped with a video camera. Thirdly, I designed and constructed a custom-built adhesion-testing device to quantify the adhesive property. The experimental results provide new insight into the microscopic structure - macroscopic property relationship at the solid-polymer interface.

  3. The Drosophila GAGA factor is required for dosage compensation in males and for the formation of the male-specific-lethal complex chromatin entry site at 12DE.

    PubMed Central

    Greenberg, Anthony J; Yanowitz, Judith L; Schedl, Paul

    2004-01-01

    Drosophila melanogaster males have one X chromosome, while females have two. To compensate for the resulting disparity in X-linked gene expression between the two sexes, most genes from the male X chromosome are hyperactivated by a special dosage compensation system. Dosage compensation is achieved by a complex of at least six proteins and two noncoding RNAs that specifically associate with the male X. A central question is how the X chromosome is recognized. According to a current model, complexes initially assemble at approximately 35 chromatin entry sites on the X and then spread bidirectionally along the chromosome where they occupy hundreds of sites. Here, we report that mutations in Trithorax-like (Trl) lead to the loss of a single chromatin entry site on the X, male lethality, and mislocalization of dosage compensation complexes. PMID:15020425

  4. UV Dosage Levels in Summer: Increased Risk of Ozone Loss from Convectively Injected Water Vapor

    NASA Astrophysics Data System (ADS)

    Wilmouth, D. M.; Smith, J. B.; Sayres, D. S.; Anderson, J.

    2012-12-01

    Elevated water vapor concentrations from convective injection have now been observed repeatedly in the lower stratosphere over the United States during the summer. Because both temperature and water vapor concentration set the threshold conditions for initiating the heterogeneous reactions that activate inorganic chlorine, the observed presence of high water vapor can fundamentally change the chemistry of the lower stratosphere by shifting inorganic chlorine into the catalytically active free-radical form, ClO. As a result, significant ozone losses may follow convective injection of water vapor into the stratosphere. The chemical system is highly sensitive to temperature, pressure, aerosol surface area, available inorganic chlorine, and concentration and duration of elevated water vapor. Were the intensity and frequency of convective injection of water vapor to increase as a result of climate forcing by the continued addition of carbon dioxide and methane to the atmosphere, increased risk of ozone loss and associated increases in ultraviolet dosage would follow.

  5. Neutron and Proton Dosages in the Upper Atmosphere from Solar Flare Radiation.

    PubMed

    Flamm, E J; Lingenfelter, R E

    1964-06-26

    The radiation dosage from secondary neutrons as well as from primary and secondary protons in the earth's atmosphere during solar particle events is calculated as a function of the solar proton flux, atmospheric depth, and geomagnetic-cutoff rigidity. The dosage in rems from secondary neutrons exceeds the dosage from protons below 30 g/cm(2) of residual atmosphere. Neutron dosages in rads are less than the dosage from primary protons at all depths above 100 g/cm(2). The maximum neutron dose to travelers in supersonic aircraft during solar particle events of the magnitude observed during the last solar cycle would be of the order of I rem.

  6. Mysterious Lattice Rotations in Adsorbed Monolayers

    NASA Astrophysics Data System (ADS)

    Diehl, Renee D.

    1997-03-01

    Lattice rotations due to a mismatch in structure have been observed in film growth for many years, probably beginning in the 1930's with the Nishiyama-Wasserman and Kurdjumov-Sachs orientations observed when fcc(111) films grow on bcc(110) surfaces, or vice versa. Early analysis of this problem was carried out with the aid of Moiré patterns and the observation that the preferred lattice orientations are those which maximize the Moiré fringe spacing. Later energy calculations indicated that the structures which were predicted by the the Moiré technique actually do correspond to energy minima. Epitaxial rotation in adsorbed monolayers is a conceptually simpler problem since in principle it involves only two planes of atoms, and it was first observed in 1977 for Ar on a graphite surface(C. G. Shaw, M. D. Chinn, S. C. Fain, Jr. Phys. Rev. Lett. 41 (1978) 955.). This observation came only a few months after a new theory, based on the expected elastic behavior of an overlayer, was developed by A. D. Novaco and J. P. McTague(A. D. Novaco and J. P. McTague, Phys. Rev. Lett. 38 (1977) 1286.), and the agreement with the experimental results was remarkable. It was later shown that a few symmetry principles similar to those used for the film growth studies sometimes can also predict the observed structures. However, the situation for incommensurate layers physisorbed on metal surfaces currently looks bleak. None of the existing theories or models appears to describe the experimental results. New data for physisorbed gases on metal surfaces will be presented, along with some half-baked (and probably wrong) ideas for what might be happening. This work was supported by NSF.

  7. Drug dosage recommendations in patients with chronic liver disease.

    PubMed

    Periáñez-Párraga, Leonor; Martínez-López, Iciar; Ventayol-Bosch, Pere; Puigventós-Latorre, Francesc; Delgado-Sánchez, Olga

    2012-04-01

    Chronic liver diseases (CLD) alter the kinetics of drugs. Despite dosage adjustment is based on Child-Pugh scores, there are no available recommendations and/or algorithms of reference to facilitate dosage regimens. A literature review about dose adjustment of the drugs from the hospital guide -which are included in the list of the WHO recommended drugs to be avoided or used with caution in patients with liver disease- was carried out. The therapeutic novelties from the last few years were also included. In order to do so, the summary of product characteristics (SPC), the database DrugDex-Micromedex, the WHO recommendations and the review articles from the last 10 years in Medline were reviewed. Moreover, the kinetic parameters of each drug were calculated with the aim of establishing a theoretical recommendation based on the proposal of Delcò and Huet. Recommendations for 186 drugs are presented according to the SPC (49.5%), DrugDex-Micromedex (26.3%) and WHO (18.8%) indications; six recommendations were based on specific publications; the theoretical recommendation based on pharmacokinetic parameters was proposed in four drugs. The final recommendations for clinical management were: dosage modification (26.9%), hepatic/analytical monitoring of the patient (8.6%), contraindication (18.8%), use with caution (19.3%) and no adjustment required (26.3%). In this review, specific recommendations for the practical management of patients with chronic liver disease are presented. It has been elaborated through a synthesis of the published bibliography and completed by following a theoretical methodology.

  8. Gene Expression Dosage Regulation in an Allopolyploid Fish

    PubMed Central

    Matos, I; Machado, M. P.; Schartl, M.; Coelho, M. M.

    2015-01-01

    How allopolyploids are able not only to cope but profit from their condition is a question that remains elusive, but is of great importance within the context of successful allopolyploid evolution. One outstanding example of successful allopolyploidy is the endemic Iberian cyprinid Squalius alburnoides. Previously, based on the evaluation of a few genes, it was reported that the transcription levels between diploid and triploid S. alburnoides were similar. If this phenomenon occurs on a full genomic scale, a wide functional ‘‘diploidization’’ could be related to the success of these polyploids. We generated RNA-seq data from whole juvenile fish and from adult livers, to perform the first comparative quantitative transcriptomic analysis between diploid and triploid individuals of a vertebrate allopolyploid. Together with an assay to estimate relative expression per cell, it was possible to infer the relative sizes of transcriptomes. This showed that diploid and triploid S. alburnoides hybrids have similar liver transcriptome sizes. This in turn made it valid to directly compare the S. alburnoides RNA-seq transcript data sets and obtain a profile of dosage responses across the S. alburnoides transcriptome. We found that 64% of transcripts in juveniles’ samples and 44% in liver samples differed less than twofold between diploid and triploid hybrids (similar expression). Yet, respectively 29% and 15% of transcripts presented accurate dosage compensation (PAA/PA expression ratio of 1 instead of 1.5). Therefore, an exact functional diploidization of the triploid genome does not occur, but a significant down regulation of gene expression in triploids was observed. However, for those genes with similar expression levels between diploids and triploids, expression is not globally strictly proportional to gene dosage nor is it set to a perfect diploid level. This quantitative expression flexibility may be a strong contributor to overcome the genomic shock, and be an

  9. On p53 revival using system oriented drug dosage design.

    PubMed

    Haseeb, Muhammad; Azam, Shumaila; Bhatti, A I; Azam, Rizwan; Ullah, Mukhtar; Fazal, Sahar

    2017-02-21

    We propose a new paradigm in the drug design for the revival of the p53 pathway in cancer cells. It is shown that the current strategy of using small molecule based Mdm2 inhibitors is not enough to adequately revive p53 in cancerous cells, especially when it comes to the extracting pulsating behavior of p53. This fact has come to notice when a novel method for the drug dosage design is introduced using system oriented concepts. As a test case, small molecule drug Mdm2 repressor Nutlin 3a is considered. The proposed method determines the dose of Nutlin to revive p53 pathway functionality. For this purpose, PBK dynamics of Nutlin have also been integrated with p53 pathway model. The p53 pathway is the focus of researchers for the last thirty years for its pivotal role as a frontline cancer suppressant protein due to its effect on cell cycle checkpoints and cell apoptosis in response to a DNA strand break. That is the reason for finding p53 being absent in more than 50% of tumor cancers. Various drugs have been proposed to revive p53 in cancer cells. Small molecule based drugs are at the foremost and are the subject of advanced clinical trials. The dosage design of these drugs is an important issue. We use control systems concepts to develop the drug dosage so that the cancer cells can be treated in appropriate time. We investigate by using a computational model how p53 protein responds to drug Nutlin 3a, an agent that interferes with the MDM2-mediated p53 regulation. The proposed integrated model describes in some detail the regulation network of p53 including the negative feedback loop mediated by MDM2 and the positive feedback loop mediated by Mdm2 mRNA as well as the reversible represses of MDM2 caused by Nutlin. The reported PBK dynamics of Nutlin 3a are also incorporated to see the full effect. It has been reported that p53 response to stresses in two ways. Either it has a sustained (constant) p53 response, or there are oscillations in p53 concentration. The

  10. Relative bioavailability of scopolamine dosage forms and interaction with dextroamphetamine.

    PubMed

    Boyd, Jason L; Du, Brian; Vaksman, Zalman; Locke, James P; Putcha, Lakshmi

    2007-07-01

    The NASA Reduced Gravity Office (RGO) uses scopolamine (SCOP) alone and in combination with dextoamphetamine (DEX) to treat motion sickness symptoms during DC-9 parabolic flights. The medications are sometimes dispensed as custom dosage forms in gelatin capsules for convenience. Reports of treatment failure during flights by the flight surgeons suggest that these formulations may be less efficacious for the treatment of motion sickness due to unreliable and inadequate bioavailability. We estimated bioavailability of four different oral formulations used by the NASA RGO physicians for the treatment of motion sickness.

  11. Comprehensive review on additives of topical dosage forms for drug delivery.

    PubMed

    Garg, Tarun; Rath, Goutam; Goyal, Amit K

    2015-12-01

    Skin is the largest organ of the human body and plays the most important role in protecting against pathogen and foreign matter. Three important modes such as topical, regional and transdermal are widely used for delivery of various dosage forms. Among these modes, the topical dosage forms are preferred because it provides local therapeutic activity when applied to the skin or mucous membranes. Additives or pharmaceutical excipients (non-drug component of dosage form) are used as inactive ingredients in dosage form or tools for structuring dosage forms. The main use of topical dosage form additives are controling the extent of absorption, maintaining the viscosity, improving the stability as well as organoleptic property and increasing the bulk of the formulation. The overall goal of this article is to provide the clinician with information related to the topical dosage form additives and their current major applications against various diseases.

  12. Method of coating aluminum substrates with solid adsorbent

    SciTech Connect

    Dunn, S.R.; McKeon, M.J.; Cohen, A.P.; Behan, A.S.

    1992-06-09

    This patent describes a method of coating a surface of an aluminum substrate with a layer of solid adsorbent selected from the group consisting of crystalline molecular sieves, activated alumina, and mixtures thereof. It comprises heating the surface in an oxygen containing atmosphere to a temperature of at least about 200{degrees} C and sufficient to enable bonding of the solid adsorbent to the surface, contacting the heated surface with a slurry comprising the adsorbent and a binder selected from the group consisting of volclay, kaolin, sepiolite, attapulgite, silicates, aluminates, activated alumina, and mixtures thereof in a suspending liquid to form a slurry-coated surface, and removing sufficient liquid to form an adsorbent coating thereon.

  13. Removal of adsorbed gases with CO2 snow

    NASA Astrophysics Data System (ADS)

    Zito, Richard R.

    1991-09-01

    During the outgassing of orbiting astronomical observatories, the condensation of molecular species on optical surfaces can create difficulties for astronomers. The problem is particularly severe in ultraviolet astronomy where the adsorption of only a few atomic layers of some substances can be very damaging. In this paper the removal of adsorbed atomic layers using carbon dioxide snow is discussed. The rate of removal of adsorbed layers of isopropyl alcohol, Freon TF, and deionized distilled water on Teflon substrates was experimentally determined. The removal of fingerprints (containing fatty acids such as stearic acid) from optical surfaces is also demonstrated. The presence and rate of removal of the multilayers was monitored by detecting the molecular dipole field of adsorbed molecular species. For isopropyl alcohol, Freon TF (trichlorotrifluoroethane), and water adsorbed multilayers were removed in under 1.5 seconds. Fingerprint removal was much more difficult and required 20 seconds of spraying with a mixture of carbon dioxide snow flakes and atomized microdroplets of isopropyl alcohol.

  14. Radiation grafted adsorbents for newly emerging environmental applications

    NASA Astrophysics Data System (ADS)

    Mahmoud Nasef, Mohamed; Ting, T. M.; Abbasi, Ali; Layeghi-moghaddam, Alireza; Sara Alinezhad, S.; Hashim, Kamaruddin

    2016-01-01

    Radiation induced grafting (RIG) is acquired to prepare a number of adsorbents for newly emerging environmental applications using a single route involving RIG of glycidymethacrylate (GMA) onto polyethylene-polypropylene (PE-PP) non-woven fabric. The grafted fabric was subjected to one of three functionalization reactions to impart desired ionic characters. This included treatment with (1) N-dimethyl-D-glucamine, (2) triethylamine and (3) triethylamine and alkalisation with KOH. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) were used to study the changes in chemical and physical structures of the obtained fibrous adsorbents. The potential applications of the three adsorbents for removal of boron from solutions, capturing CO2 from CO2/N2 mixtures and catalysing transesterification of triacetin/methanol to methyl acetate (biodiesel) were explored. The obtained fibrous adsorbents provide potential alternatives to granular resins for the investigated applications and require further development.

  15. Trace contaminant studies of HSC adsorbent. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Yieh, D. T. N.

    1978-01-01

    The adsorption and desorption of fifteen trace contaminants on HSC (polyethylenimine coated acrylic ester) adsorbent were experimentally investigated with the following two objectives: to test the removal potential and the adsorption reversibility of the selected trace contaminants, and to test the effect a preadsorbed trace contaminant has on the CO2 adsorption capacity. The experimental method for acquiring the adsorption equilibrium data used is based on the volumetric (or displacement) concept of vacuum adsorption. From the experimental results, it was found that the HSC adsorbent has good adsorption potential for contaminants of alcohol compounds, esters, and benzene compounds; whereas, adsorption of ketone compounds, oxidizing and reducing agents are detrimental to the adsorbent. In addition, all liquid contaminants reduce the CO2 capacity of HSC adsorbent.

  16. Electronic structure of benzene adsorbed on Ni and Cu surfaces

    SciTech Connect

    Weinelt, M.; Nilsson, A.; Wassdahl, N.

    1997-04-01

    Benzene has for a long time served as a prototype adsorption system of large molecules. It adsorbs with the molecular plane parallel to the surface. The bonding of benzene to a transition metal is typically viewed to involve the {pi} system. Benzene adsorbs weakly on Cu and strongly on Ni. It is interesting to study how the adsorption strength is reflected in the electronic structure of the adsorbate-substrate complex. The authors have used X-ray Emission (XE) and X-ray Absorption (XA) spectroscopies to selectively study the electronic states localized on the adsorbed benzene molecule. Using XES the occupied states can be studies and with XAS the unoccupied states. The authors have used beamline 8.0 and the Swedish endstation equipped with a grazing incidence x-ray spectrometer and a partial yield absorption detector. The resolution in the XES and XAS were 0.5 eV and 0.05 eV, respectively.

  17. Oil palm biomass as an adsorbent for heavy metals.

    PubMed

    Vakili, Mohammadtaghi; Rafatullah, Mohd; Ibrahim, Mahamad Hakimi; Abdullah, Ahmad Zuhairi; Salamatinia, Babak; Gholami, Zahra

    2014-01-01

    Many industries discharge untreated wastewater into the environment. Heavy metals from many industrial processes end up as hazardous pollutants of wastewaters.Heavy metal pollution has increased in recent decades and there is a growing concern for the public health risk they may pose. To remove heavy metal ions from polluted waste streams, adsorption processes are among the most common and effective treatment methods. The adsorbents that are used to remove heavy metal ions from aqueous media have both advantages and disadvantages. Cost and effectiveness are two of the most prominent criteria for choosing adsorbents. Because cost is so important, great effort has been extended to study and find effective lower cost adsorbents.One class of adsorbents that is gaining considerable attention is agricultural wastes. Among many alternatives, palm oil biomasses have shown promise as effective adsorbents for removing heavy metals from wastewater. The palm oil industry has rapidly expanded in recent years, and a large amount of palm oil biomass is available. This biomass is a low-cost agricultural waste that exhibits, either in its raw form or after being processed, the potential for eliminating heavy metal ions from wastewater. In this article, we provide background information on oil palm biomass and describe studies that indicate its potential as an alternative adsorbent for removing heavy metal ions from wastewater. From having reviewed the cogent literature on this topic we are encouraged that low-cost oil-palm-related adsorbents have already demonstrated outstanding removal capabilities for various pollutants.Because cost is so important to those who choose to clean waste streams by using adsorbents, the use of cheap sources of unconventional adsorbents is increasingly being investigated. An adsorbent is considered to be inexpensive when it is readily available, is environmentally friendly, is cost-effective and be effectively used in economical processes. The

  18. Removal of aqueous nickel (II) using laterite as a low-cost adsorbent.

    PubMed

    Mukherjee, Somnath; Kumar, Sunil; Misra, A K; Acharya, P C

    2006-10-01

    The present paper describes the laboratory study of laterite as a low-cost adsorbent for removal of aqueous nickel (II). At pH 7 and a temperature of 30 degrees C, a sorbent dose of 15 mg/L resulted in approximately 90% removal of nickel (II) from its initial concentration of 10 mg/L. A maximum removal of 98% of the adsorbate was observed with an adsorbent particle size of 210 micro with the above conditions. Batch kinetics results were described by fitting in a Langmuir isotherm. Helffrich's half-time equation (Helffrich, 1962) has been applied to evaluate the adsorption process. It appears that film diffusion would be the rate-limiting step. The effect of pH on the sorption process was carried out to a value of 8.0. The removal rate of nickel was found to be the function of pH of the reaction mixture. The rate of nickel uptake by laterite with the decrease in pH value has been explained on the basis of aqueous-complex formation and the subsequent acid-base dissociation at the solid-solution interface.

  19. Magnetically modified sheaths of Leptothrix sp. as an adsorbent for Amido black 10B removal

    NASA Astrophysics Data System (ADS)

    Angelova, Ralitsa; Baldikova, Eva; Pospiskova, Kristyna; Safarikova, Mirka; Safarik, Ivo

    2017-04-01

    The goal of this study was to assess the biosorption of Amido black 10B dye from aqueous solutions on magnetically modified sheaths of Leptothrix sp. in a batch system. The magnetic modification of the sheaths was performed using both microwave synthesized iron oxide nano- and microparticles and perchloric acid stabilized ferrofluid. The native and both magnetically modified sheaths were characterized by SEM. Various parameters significantly affecting the adsorption process, such as pH, contact time, temperature and initial concentration, were studied in detail using the adsorbent magnetized by both methods. The highest adsorption efficiency was achieved at pH 2. The maximum adsorption capacities of both types of magnetized material at room temperature were found to be 339.2 and 286.1 mg of dye per 1 g of ferrofluid modified and microwave synthesized particles modified adsorbent, respectively. Thermodynamic study of dye adsorption revealed a spontaneous and endothermic process in the temperature range between 279.15 and 313.15 K. The data were fitted to various equilibrium and kinetic models. Experimental data matched well with the pseudo-second-order kinetics and Freundlich isotherm model. The Leptothrix sheaths have excellent efficacy for dye adsorption. This material can be used as an effective, low-cost adsorbent.

  20. Development of drug adsorbates onto soluble inorganic silicate glass surface: example with acetaminophen.

    PubMed

    Hristova, Yoanna; Djambaski, Peter; Samuneva, Biserka; Rangelova, Nadya; Bogdanova, Svetla

    2008-02-01

    A ternary melt-derived inorganic glass system (Igl) of composition corresponding to 62SiO(2), 35Na(2)O, 3Al(2)O(3 )(wt.%) has been formulated and studied as a drug carrier. The [Al(2)O(3)/Na(2)O] ratio is less than one and the aluminium ion is a network former that retards the glass dissolution. The processing conditions lead to a brittle, easily grinding, amorphous product. The Igl structure was proven by IR-spectroscopy, energy-dispersive spectrometry, X-ray diffraction, scanning electron microscopy. A very important fact established is that the Igl corrosion (dissolution) is pH-dependent. Inorganic glass system was transformed into model acetaminophen (APH) adsorbate (APH/Igla 1:1(w/w)) with mild experimental conditions and evaluated as a drug carrier. No interactions between Igl and APH during the processing were proven. Besides, APH settles onto the glass surface as crystalline phase. A lower extent of corrosion, apparent solubility and delayed in vitro APH release from the adsorbate in water and artificial gastric juice in comparison to the samples untreated drug and APH/Iglm physical mixture were established. It is hypothesized that the glass decomposition products, formed into contact with a solvent, initiate interactions with APH at the glass/solution interface. Similar behaviour of the Igl and its drug adsorbates could be expected in gastro-intestinal tract.

  1. Coherent anti-Stokes Raman scattering enhancement of thymine adsorbed on graphene oxide

    PubMed Central

    2014-01-01

    Coherent anti-Stokes Raman scattering (CARS) of carbon nanostructures, namely, highly oriented pyrolytic graphite, graphene nanoplatelets, graphene oxide, and multiwall carbon nanotubes as well CARS spectra of thymine (Thy) molecules adsorbed on graphene oxide were studied. The spectra of the samples were compared with spontaneous Raman scattering (RS) spectra. The CARS spectra of Thy adsorbed on graphene oxide are characterized by shifts of the main bands in comparison with RS. The CARS spectra of the initial nanocarbons are definitely different: for all investigated materials, there is a redistribution of D- and G-mode intensities, significant shift of their frequencies (more than 20 cm-1), and appearance of new modes about 1,400 and 1,500 cm-1. The D band in CARS spectra is less changed than the G band; there is an absence of 2D-mode at 2,600 cm-1 for graphene and appearance of intensive modes of the second order between 2,400 and 3,000 cm-1. Multiphonon processes in graphene under many photon excitations seem to be responsible for the features of the CARS spectra. We found an enhancement of the CARS signal from thymine adsorbed on graphene oxide with maximum enhancement factor about 105. The probable mechanism of CARS enhancement is discussed. PMID:24948887

  2. Treatment of malachite green-containing wastewater using poultry feathers as adsorbent.

    PubMed

    Beak, Mi H; Ijagbemi, Christianah O; Kim, Dong S

    2009-04-01

    The feasibility of using feathers, a waste from poultry as an absorbent for malachite green in dye wastewater was studied. The batch adsorption tests were shown to be influenced by the concentration of the dye, reaction temperature, solution pH, and pre-treatment with ethanol. In order to establish the equilibrium state of the process, a kinetic study was conducted for an optimal practice of adsorption treatment process. The adsorption reached equilibrium within 120 min in the range of dye concentration studied. It was found that the adsorption rate increases especially at low concentrations of dye and the adsorption data fitted well to the first-order reaction kinetics over all dye concentration range. Absolute amount of adsorbed malachite green at equilibrium condition decreased as concentration decreases. Adsorption of malachite green on poultry feathers fitted well to the Langmuir isotherm model. As temperature increases, the adsorbed amount of malachite green at equilibrium also increased, indicating an endothermic adsorption reaction. In addition, the color removal of malachite green rapidly increased with increase in dye's water pH. The pre-treatment of adsorbent with ethanol produced initial slow rate of malachite green removal but after about 100 min of reaction time, same removal rate was observed compare with the untreated feathers.

  3. A regenerable oxide-based H2S adsorbent with nanofibrous morphology

    NASA Astrophysics Data System (ADS)

    Behl, Mayank; Yeom, Junghoon; Lineberry, Quentin; Jain, Prashant K.; Shannon, Mark A.

    2012-12-01

    Hydrogen sulphide is found in raw fuels such as natural gas and coal/biomass-derived syngas. It is poisonous to catalysts and corrosive to metals and therefore needs to be removed. This is often achieved using metal oxides as reactive adsorbents, but metal oxides perform poorly when subjected to repeated cycles of sulphidation and re-oxidation as a result of complex structural and chemical changes. Here, we show that Zn-Ti-O-based adsorbents with nanofibrous morphology can sustain their initial reactivity and sulphur removal capacity over multiple regeneration cycles. These nanostructured sorbents offer rapid reaction rates that overcome the gas-transport limitations of conventional pellet-based sorbents and allow all of the material to be used efficiently. Regeneration can be carried out at the same temperature as the sulphidation step because of the higher reactivity, which prevents sorbent deterioration and reduces energy use. The efficient regeneration of the adsorbent is also aided by structural features such as the growth of hierarchical nanostructures and preferential stabilization of a wurtzite phase in the sulphidation product.

  4. ZrO2-functionalized magnetic mesoporous SiO2 as effective phosphate adsorbent.

    PubMed

    Wang, Wenjuan; Zhou, Juan; Wei, Dan; Wan, Haiqin; Zheng, Shourong; Xu, Zhaoyi; Zhu, Dongqiang

    2013-10-01

    Phosphate pollution may cause eutrophication of the aquatic environment. In the present study, magnetic mesoporous SiO2 (denoted as MMS) and ZrO2-functionalized magnetic mesoporous SiO2 (denoted as ZrO2-MMS) were prepared and phosphate adsorption over the materials was investigated. The adsorbents were characterized by X-ray diffraction, transition electron microscopy, vibration sample magnetometer, N2 adsorption/desorption, zeta-potential measurement, and X-ray photoelectron spectroscopy. The results showed that MMS consisted of magnetite with particle sizes of 10-20 nm and ordered mesoporous SiO2 with the most probable pore diameter of 2.0 nm. The adsorbents could be readily separated and recovered under external magnetic field. The surface grafting of ZrO2 onto MMS led to an increase in surface zeta potential due to the formation of covalently linked ZrO2 functionality on the surface of MMS. Moreover, ZrO2 functionalization resulted in enhanced phosphate adsorption. Phosphate adsorption isotherms over the adsorbents could be well described by the Freundlich model. Phosphate adsorption kinetics followed the pseudo-second-order kinetics and the adsorption rate decreased with initial phosphate concentration. Additionally, increasing pH led to suppressed phosphate adsorption, and phosphate adsorption slightly increased with ionic strength.

  5. Preventive obesity agent montmorillonite adsorbs dietary lipids and enhances lipid excretion from the digestive tract

    PubMed Central

    Xu, Pengfei; Dai, Shu; Wang, Jing; Zhang, Jun; Liu, Jin; Wang, Fang; Zhai, Yonggong

    2016-01-01

    Western diets are typically high in fat and are associated with long-term complications such as obesity and hepatic steatosis. Because of the enjoyable taste of high-fat diets (HFDs), we are interested in determining how to decrease lipid absorption and enhance lipid excretion from the digestive tract after the consumption of eating fatty foods. Montmorillonite was initially characterized as a gastrointestinal mucosal barrier protective agent for the treatment of diarrhoea. Dietary lipid adsorbent- montmorillonite (DLA-M) was isolated and purified from Xinjiang montmorillonite clay via the water extraction method. Here, we show that DLA-M has an unexpected role in preventing obesity, hyperlipidaemia and hepatic steatosis in HFD-fed rats. Interestingly, combined application of polarized light microscopy and lipid staining analyses, showed that DLA-M crystals have dietary lipid-adsorbing ability in vitro and in vivo, which enhances lipid excretion via bowel movements. In summary, our results indicate that DLA-M prevent HFD-induced obesity. This novel dietary lipid-adsorbing agent can help prevent obesity and its comorbidities. PMID:26891902

  6. Increased Maternal Genome Dosage Bypasses the Requirement of the FIS Polycomb Repressive Complex 2 in Arabidopsis Seed Development

    PubMed Central

    Kradolfer, David; Hennig, Lars; Köhler, Claudia

    2013-01-01

    Seed development in flowering plants is initiated after a double fertilization event with two sperm cells fertilizing two female gametes, the egg cell and the central cell, leading to the formation of embryo and endosperm, respectively. In most species the endosperm is a polyploid tissue inheriting two maternal genomes and one paternal genome. As a consequence of this particular genomic configuration the endosperm is a dosage sensitive tissue, and changes in the ratio of maternal to paternal contributions strongly impact on endosperm development. The FERTILIZATION INDEPENDENT SEED (FIS) Polycomb Repressive Complex 2 (PRC2) is essential for endosperm development; however, the underlying forces that led to the evolution of the FIS-PRC2 remained unknown. Here, we show that the functional requirement of the FIS-PRC2 can be bypassed by increasing the ratio of maternal to paternal genomes in the endosperm, suggesting that the main functional requirement of the FIS-PRC2 is to balance parental genome contributions and to reduce genetic conflict. We furthermore reveal that the AGAMOUS LIKE (AGL) gene AGL62 acts as a dosage-sensitive seed size regulator and that reduced expression of AGL62 might be responsible for reduced size of seeds with increased maternal genome dosage. PMID:23326241

  7. A comparative study of sertraline dosages, plasma concentrations, efficacy and adverse reactions in Chinese versus Caucasian patients.

    PubMed

    Hong Ng, Chee; Norman, Trevor R; Naing, Khin Ohnmar; Schweitzer, Isaac; Kong Wai Ho, Brian; Fan, Agnes; Klimidis, Steven

    2006-03-01

    This prospective 6-week study examined the differences in dosage and steady state plasma concentrations of sertraline in Chinese versus Caucasian depressed patients. Two groups of Chinese patients from different geographical sites and a group of Caucasian patients were evaluated with clinical measures during an initial dose of 50 mg/day, with subsequent doses adjusted clinically. The results of 17 Australian Chinese (ACHI), 13 Malaysian Chinese (MCHI) and 15 Australian Caucasians (AC) were analysed. Despite controlling for weight, the AC subjects received a significantly higher dose than both the ACHI (P = 0.002) and the MCHI groups (P = 0.012). However, the mean sertraline concentration to dose ratios at weeks 1 and 6 were not significantly different between the three groups. Sertraline was effective and well tolerated in both ethnic groups with few adverse events. Although there was a lack of difference between groups in the pharmacokinetic results, Chinese depressed patients appeared to require lower dosages with consequently lower plasma concentrations of sertraline compared to Caucasian patients to achieve clinical efficacy. Further studies of the dosages, kinetics and adverse effects of selective serotonin reuptake inhibitors linked with genotyping are necessary.

  8. Residence time determination for adsorbent beds of different configurations

    SciTech Connect

    Otermat, J.E.; Wikoff, W.O.; Kovach, J.L.

    1995-02-01

    The residence time calculations of ASME AG-1 Code, Section FC, currently specify a screen surface area method, that is technically incorrect. Test data has been obtained on Type II adsorber trays of different configurations to establish residence time in the adsorber trays. These data indicate that the air volume/carbon volume ratio or the average screen area are more appropriate for the calculation of the residence time calculation than the currently used, smallest screen area basis.

  9. Structure of water adsorbed on a single graphene sheet

    NASA Astrophysics Data System (ADS)

    Gordillo, M. C.; Martí, J.

    2008-08-01

    We present the result of molecular-dynamics simulations of water adsorbed on top of a single graphene layer at temperatures between 25 and 50°C . The analysis of the energy per particle and the density profiles indicate that the behavior of the adsorbed liquid is similar to the case of multiple graphene layers (graphite) with the only difference being the values of configurational energy. Other structural properties, such as stability ranges, hydrogen bond distributions, and molecular orientations are also presented.

  10. Indications, usage, and dosage of the transfer factor.

    PubMed

    Berrón-Pérez, Renato; Chávez-Sánchez, Raúl; Estrada-García, Iris; Espinosa-Padilla, Sara; Cortez-Gómez, Rudyard; Serrano-Miranda, Ernestina; Ondarza-Aguilera, Rodolfo; Pérez-Tapia, Mayra; Pineda Olvera, Benjamín; Jiménez-Martínez, María del Carmen; Portugués, Abraham; Rodríguez, Azucena; Cano, Laura; Pacheco, Pedro Urcino; Barrientos, Javier; Chacón, Rommel; Serafín, Jeannet; Mendez, Patricia; Monges, Abelardo; Cervantes, Edgar; Estrada-Parra, Sergio

    2007-01-01

    The transfer factor (TF) was described in 1955 by S. Lawrence. In 1992 Kirkpatrick characterized the specific TF at molecular level. The TF is constituted by a group of numerous molecules, of low molecular weight, from 1.0 to 6.0 kDa. The 5 kDa fraction corresponds to the TF specific to antigens. There are a number of publications about the clinical indications of the TF for diverse diseases, in particular those where the cellular immune response is compromised or in those where there is a deficient regulation of the immune response. In this article we present our clinical and basic experiences, especially regarding the indications, usage and dosage of the TF. Our group demonstrated that the TF increases the expression of IFN-gamma and RANTES, while decreases the expression of osteopontine. Using animal models we have worked with M. tuberculosis, and with a model of glioma with good therapeutic results. In the clinical setting we have worked with herpes zoster, herpes simplex type I, herpetic keratitis, atopic dermatitis, osteosarcoma, tuberculosis, asthma, post-herpetic neuritis, anergic coccidioidomycosis, leishmaniasis, toxoplasmosis, mucocutaneous candidiasis, pediatric infections produced by diverse pathogen germs, sinusitis, pharyngitis, and otits media. All of these diseases were studied through protocols which main goals were to study the therapeutic effects of the TF, and to establish in a systematic way diverse dosage schema and time for treatment to guide the prescription of the TF.

  11. Comparative multiplex dosage analysis in spinocerebellar ataxia type 2 patients.

    PubMed

    Calì, F; Chiavetta, V; Ragalmuto, A; Vinci, M; Ruggeri, G; Schinocca, P; Romano, V

    2013-04-12

    We developed a new application of comparative multiplex dosage analysis (CMDA) for evaluation of the ataxin 2 gene. Expansions of the triplet CAG can cause spinocerebellar ataxia type 2 (SCA2), a neurodegenerative disease with an autosomal-dominant mode of inheritance. Molecular diagnosis of SCA2 is routinely based on the use of conventional PCR to detect the CAG expansion. However, PCR does not amplify an allele with an expansion of many triplets (>80), which is typically found in infantile and juvenile forms of SCA2, thus leading to false negatives. We propose the analysis of the ATXN2 gene by CMDA to complement existing methods currently used for the detection of large expansions of the CAG repeat. Using CMDA, the presence of any longer mutated allele in a heterozygous patient or fetus would be inferred due to dosage variation of the very frequent normal allele #22. CMDA can be completed in 1 day, at very low cost, and would be a useful tool for prenatal diagnosis and for diagnosis of presymptomatic forms of early-onset SCA2.

  12. X-Chromosome Dosage and the Response to Cerebral Ischemia

    PubMed Central

    Turtzo, L. Christine; Siegel, Chad; McCullough, Louise D.

    2011-01-01

    Gonadal hormones contribute to ischemic neuroprotection, but cannot fully explain the observed sexual dimorphism in stroke outcomes seen during life stages with low sex steroid hormones. Sex chromosomal complement (XX in females; XY in males) may also contribute to ischemic sexual dimorphism. A transient middle cerebral artery occlusion model was used to investigate the role of X chromosome dosage in female XX and XO littermates of two mouse strains (Paf and EdaTa). Cohorts of XX and XO gonadally intact, ovariectomized, and ovariectomized females supplemented with estrogen were examined. Infarct sizes were equivalent between ovariectomized XX and XO mice, between intact XX and XO mice, and between estrogen-supplemented ovariectomized XX and XO mice. This is the first study to investigate the role of sex chromosome dosage in the response to cerebral ischemia. Neither the number of X chromosomes, nor the parent of origin of the remaining X chromosome, had a significant effect on the degree of cerebral infarction after experimental stroke in adult female mice. Estrogen was protective against cerebral ischemia in both XX and XO mice. PMID:21917808

  13. RFID Tag Helix Antenna Sensors for Wireless Drug Dosage Monitoring

    PubMed Central

    Huang, Haiyu; Zhao, Peisen; Chen, Pai-Yen; Ren, Yong; Liu, Xuewu; Ferrari, Mauro; Hu, Ye; Akinwande, Deji

    2014-01-01

    Miniaturized helix antennas are integrated with drug reservoirs to function as RFID wireless tag sensors for real-time drug dosage monitoring. The general design procedure of this type of biomedical antenna sensors is proposed based on electromagnetic theory and finite element simulation. A cost effective fabrication process is utilized to encapsulate the antenna sensor within a biocompatible package layer using PDMS material, and at the same time form a drug storage or drug delivery unit inside the sensor. The in vitro experiment on two prototypes of antenna sensor-drug reservoir assembly have shown the ability to monitor the drug dosage by tracking antenna resonant frequency shift from 2.4–2.5-GHz ISM band with realized sensitivity of 1.27 \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$\\mu~{\\rm l}/{\\rm MHz}$\\end{document} for transdermal drug delivery monitoring and 2.76-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$\\mu~{\\rm l}/{\\rm MHz}$\\end{document} sensitivity for implanted drug delivery monitoring. PMID:27170865

  14. A genome wide dosage suppressor network reveals genomic robustness

    PubMed Central

    Patra, Biranchi; Kon, Yoshiko; Yadav, Gitanjali; Sevold, Anthony W.; Frumkin, Jesse P.; Vallabhajosyula, Ravishankar R.; Hintze, Arend; Østman, Bjørn; Schossau, Jory; Bhan, Ashish; Marzolf, Bruz; Tamashiro, Jenna K.; Kaur, Amardeep; Baliga, Nitin S.; Grayhack, Elizabeth J.; Adami, Christoph; Galas, David J.; Raval, Alpan; Phizicky, Eric M.; Ray, Animesh

    2017-01-01

    Genomic robustness is the extent to which an organism has evolved to withstand the effects of deleterious mutations. We explored the extent of genomic robustness in budding yeast by genome wide dosage suppressor analysis of 53 conditional lethal mutations in cell division cycle and RNA synthesis related genes, revealing 660 suppressor interactions of which 642 are novel. This collection has several distinctive features, including high co-occurrence of mutant-suppressor pairs within protein modules, highly correlated functions between the pairs and higher diversity of functions among the co-suppressors than previously observed. Dosage suppression of essential genes encoding RNA polymerase subunits and chromosome cohesion complex suggests a surprising degree of functional plasticity of macromolecular complexes, and the existence of numerous degenerate pathways for circumventing the effects of potentially lethal mutations. These results imply that organisms and cancer are likely able to exploit the genomic robustness properties, due the persistence of cryptic gene and pathway functions, to generate variation and adapt to selective pressures. PMID:27899637

  15. Ultraconserved Elements: Analyses of Dosage Sensitivity, Motifs and Boundaries

    PubMed Central

    Chiang, Charleston W. K.; Derti, Adnan; Schwartz, Daniel; Chou, Michael F.; Hirschhorn, Joel N.; Wu, C.-ting

    2008-01-01

    Ultraconserved elements (UCEs) are sequences that are identical between reference genomes of distantly related species. As they are under negative selection and enriched near or in specific classes of genes, one explanation for their ultraconservation may be their involvement in important functions. Indeed, many UCEs can drive tissue-specific gene expression. We have demonstrated that nonexonic UCEs are depleted among segmental duplications (SDs) and copy number variants (CNVs) and proposed that their ultraconservation may reflect a mechanism of copy counting via comparison. Here, we report that nonexonic UCEs are also depleted among 10 of 11 recent genomewide data sets of human CNVs, including 3 obtained with strategies permitting greater precision in determining the extents of CNVs. We further present observations suggesting that nonexonic UCEs per se may contribute to this depletion and that their apparent dosage sensitivity was in effect when they became fixed in the last common ancestor of mammals, birds, and reptiles, consistent with dosage sensitivity contributing to ultraconservation. Finally, in searching for the mechanism(s) underlying the function of nonexonic UCEs, we have found that they are enriched in TAATTA, which is also the recognition sequence for the homeodomain DNA-binding module, and bounded by a change in A + T frequency. PMID:18957701

  16. Genomic dosage effects on heterosis in triploid maize.

    PubMed

    Yao, Hong; Dogra Gray, Anjali; Auger, Donald L; Birchler, James A

    2013-02-12

    The genetic basis of hybrid vigor or heterosis has been debated for more than a century. A popular hypothesis to explain this phenomenon is that there are different slightly deleterious recessive homozygous alleles in the two parents and that these alleles are complemented in the hybrid so that the biomass and fertility exceed both parents. To address the complementation hypothesis in a direct manner, heterosis was examined in diploid inbreds and reciprocal hybrids and compared with matched triploid inbred derivatives and two types of triploid hybrids that differ in the number of genomes from the different parents. Complementation of recessive mutations would occur equally in the two types of triploid hybrids predicting that, if this complementation were the sole basis of the heterotic response, the two types of triploid hybrids would be equivalent for hybrid vigor. However, the reciprocal diploid hybrids were similar for six of nine measured traits, but the two types of triploid hybrids differed significantly for eight of the same traits. Importantly, the triploid hybrids differed in the level of high-parent heterosis relative to the derived triploid inbreds. Also, the differences observed between the reciprocal triploid hybrids correlated strongly with differences observed between the inbreds, either at the diploid or triploid level, in a manner explicable by genome dosage rather than parent of origin effects. The findings of this study suggest that a major component of heterosis is a mechanism that is modulated by dosage-sensitive factors that involves allelic diversity across the genome.

  17. Stability of pharmaceutical salts in solid oral dosage forms.

    PubMed

    Nie, Haichen; Byrn, Stephen R; Zhou, Qi Tony

    2017-03-09

    Using pharmaceutical salts in solid dosage forms can raise stability concerns, especially salt dissociation which can adversely affect the product performance. Therefore, a thorough understanding of the salt instability encountered in solid state formulations is imperative to ensure the product quality. The present article uses the fundamental theory of acid base, ionic equilibrium, relationship of pH and solubility as a starting point to illustrate and interpret the salt formation and salt disproportionation in pharmaceutical systems. The criteria of selecting the optimal salt form and the underlying theory of salt formation and disproportionation are reviewed in detail. Factors influencing salt stability in solid dosage forms are scrutinized and discussed with the case studies. In addition, both commonly used and innovative strategies for preventing salt dissociations in formulation, on storage, and during manufacturing will be suggested herein. This article will provide formulation scientists and manufacturing engineers an insight into the mechanisms of salt disproportionation and salt formation, which can help them avoid and solve the instability issues of pharmaceutical salts in the product design.

  18. Biowaiver monographs for immediate release solid oral dosage forms: metronidazole.

    PubMed

    Rediguieri, Camila F; Porta, Valentina; G Nunes, Diana S; Nunes, Taina M; Junginger, Hans E; Kopp, Sabine; Midha, Kamal K; Shah, Vinod P; Stavchansky, Salomon; Dressman, Jennifer B; Barends, Dirk M

    2011-05-01

    Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing metronidazole are reviewed. Metronidazole can be assigned to Biopharmaceutics Classification System Class I. Most BE studies that were identified reported the investigated formulations to be bioequivalent, indicating the risk of bioinequivalence to be low. Formulations showing differences in bioavailability showed dissimilarities in in vitro dissolution profiles. Furthermore, metronidazole has a wide therapeutic index. It is concluded that a biowaiver for solid IR formulations is justified, provided: (a) the test product and its comparator are both rapidly dissolving; (b) meet similarity of the dissolution profiles at pH 1.2, 4.5, and 6.8; (c) the test product contains only excipients present in IR drug products approved in International Conference on Harmonisation (ICH) or associated countries in the same dosage form; and (d) if the test product contains sorbitol, sodium laurilsulfate, or propylene glycol, the test product needs to be qualitatively and quantitatively identical to its comparator with respect to these excipients [corrected]..

  19. Biowaiver monographs for immediate release solid oral dosage forms: efavirenz.

    PubMed

    Cristofoletti, Rodrigo; Nair, Anita; Abrahamsson, Bertil; Groot, D W; Kopp, Sabine; Langguth, Peter; Polli, James E; Shah, Vinod P; Dressman, Jennifer B

    2013-02-01

    Literature data pertaining to the decision to allow a waiver of in vivo bioequivalence testing for the approval of immediate-release (IR) solid oral dosage forms containing efavirenz as the only active pharmaceutical ingredient (API) are reviewed. Because of lack of conclusive data about efavirenz's permeability and its failure to comply with the "high solubility" criteria according to the Biopharmaceutics Classification System (BCS), the API can be classified as BCS Class II/IV. In line with the solubility characteristics, the innovator product does not meet the dissolution criteria for a "rapidly dissolving product." Furthermore, product variations containing commonly used excipients or in the manufacturing process have been reported to impact the rate and extent of efavirenz absorption. Despite its wide therapeutic index, subtherapeutic levels of efavirenz can lead to treatment failure and also facilitate the emergence of efavirenz-resistant mutants. For all these reasons, a biowaiver for IR solid oral dosage forms containing efavirenz as the sole API is not scientifically justified for reformulated or multisource drug products.

  20. Efforts to Consolidate Chalcogels with Adsorbed Iodine

    SciTech Connect

    Riley, Brian J.; Pierce, David A.; Chun, Jaehun

    2013-08-28

    This document discusses ongoing work with non-oxide aerogels, called chalcogels, that are under development at the Pacific Northwest National Laboratory as sorbents for gaseous iodine. Work was conducted in fiscal year 2012 to demonstrate the feasibility of converting Sn2S3 chalcogel without iodine into a glass. This current document summarizes the work conducted in fiscal year 2013 to assess the consolidation potential of non-oxide aerogels with adsorbed iodine. The Sn2S3 and Sb13.5Sn5S20 chalcogels were selected for study. The first step in the process for these experiments was to load them with iodine (I2). The I2 uptake was ~68 mass% for Sn2S3 and ~50 mass% for Sb13.5Sn5S20 chalcogels. X-ray diffraction (XRD) of both sets of sorbents showed that metal-iodide complexes were formed during adsorption, i.e., SnI4 for Sn2S3 and SbI3 for Sb13.5Sn5S20. Additionally, metal-sulfide-iodide complexes were formed, i.e., SnSI for Sn2S3 and SbSI for Sb13.5Sn5S20. No XRD evidence for unreacted iodine was found in any of these samples. Once the chalcogels had reached maximum adsorption, the consolidation potential was assessed. Here, the sorbents were heated for consolidation in vacuum-sealed quartz vessels. The Sb13.5Sn5S20 chalcogel was heated both (1) in a glassy carbon crucible within a fused quartz tube and (2) in a single-containment fused quartz tube. The Sn2S3 chalcogel was only heated in a single-containment fused quartz tube. In both cases with the single-containment fused quartz experiments, the material consolidated nicely. However, in both cases, there were small fractions of metal iodides not incorporated into the final product as well as fused quartz particles within the melt due to the sample attacking the quartz wall during the heat treatment. The Sb13.5Sn5S20 did not appear to attack the glassy carbon crucible so, for future experiments, it would be ideal to apply a coating, such as pyrolytic graphite, to the inner walls of the fused quartz vessel to prevent

  1. Cryogenic adsorber design in a helium refrigeration system

    NASA Astrophysics Data System (ADS)

    Hu, Zhongjun; Zhang, Ning; Li, Zhengyu; Li, Q.

    2012-06-01

    The cryogenic adsorber is specially designed to eliminate impurities in gaseous helium such as O2, and N2 which is normally difficult to remove, based on the reversible cryotrapping of impurities on an activated carbon bed. The coconut shell activated carbon is adopted because of its developed micropore structure and specific surface area. This activated carbon adsorption is mostly determined by the micropore structure, and the adsorption rate of impurities is inversely proportional to the square of the particle sizes. The active carbon absorber's maximum permissible flow velocity is 0.25 m/s. When the gas flow velocity increases, the adsorption diffusion rate of the adsorbent is reduced, because an increase in the magnitude of the velocity resulted in a reduced amount of heat transfer to a unit volume of impure gas. According to the numerical simulation of N2 adsorption dynamics, the appropriate void tower link speed and the saturated adsorption capacity are determined. Then the diameter and height of the adsorber are designed. The mass transfer length should be taken into account in the adsorber height design. The pressure decrease is also calculated. The important factors that influence the adsorber pressure decrease are the void tower speed, the adsorbed layer height, and the active carbon particle shape and size.

  2. Evaluation of a cesium adsorbent grafted with ammonium 12-molybdophosphate

    NASA Astrophysics Data System (ADS)

    Shibata, Takuya; Seko, Noriaki; Amada, Haruyo; Kasai, Noboru; Saiki, Seiichi; Hoshina, Hiroyuki; Ueki, Yuji

    2016-02-01

    A fibrous cesium (Cs) adsorbent was developed using radiation-induced graft polymerization with a cross-linked structure containing a highly stable adsorption ligand. The ligand, ammonium 12-molybdophosphate (AMP), was successfully introduced onto the fibrous polyethylene trunk material. The resulting Cs adsorbent contained 36% nonwoven fabric polyethylene (NFPE), 1% AMP, 2% triallyl isocyanurate (TAIC) and 61% glycidyl methacrylate (GMA). The adsorbent's Cs adsorption capacity was evaluated using batch and column tests. It was determined that the adsorbent could be used in a wide pH range. The amount of desorbed molybdenum, which can be used as an estimate for AMP stability on the Cs adsorbent, was minimized at the standard drinking water pH range of 5.8-8.6. Based from the inspection on the adherence of these results to the requirements set forth by the Food Sanitation Act by a third party organization, it can be concluded that the developed Cs adsorbent can be safely utilized for drinking water.

  3. Equilibrium, kinetic and sorber design studies on the adsorption of Aniline blue dye by sodium tetraborate-modified Kaolinite clay adsorbent.

    PubMed

    Unuabonah, Emmanuel I; Adebowale, Kayode O; Dawodu, Folasegun A

    2008-09-15

    Raw Kaolinite clay obtained Ubulu-Ukwu, Delta State of Nigeria and its sodium tetraborate (NTB)-modified analogue was used to adsorb Aniline blue dye. Fourier transformed infrared spectra of NTB-modified Kaolinite suggests that modification was effective on the surface of the Kaolinite clay with the strong presence of inner -OH functional group. The modification of Kaolinite clay raised its adsorption capacity from 1666 to 2000 mg/kg. Modeling adsorption data obtained from both unmodified and NTB-modified Kaolinite clay reveals that the adsorption of Aniline blue dye on unmodified Kaolinite clay is on heterogeneous adsorption sites because it followed strongly the Freundlich isotherm equation model while adsorption data from NTB-modified Kaolinite clay followed strongly the Langmuir isotherm equation model which suggest that Aniline blue dye was adsorb homogeneous adsorption sites on the NTB-modified adsorbent surface. There was an observed increase in the amount of Aniline blue adsorbed as initial dye concentration was increased from 10 to 30 mg/L. It was observed that kinetic data obtained generally gave better robust fit to the second-order kinetic model (SOM). The initial sorption rate was found to increased with increasing initial dye concentration (from 10 to 20 mg/L) for data obtained from 909 to 1111 mg kg(-1)min(-1) for unmodified and 3325-5000 mg kg(-1) min(-1) for NTB-modified adsorbents. Thereafter there was a decrease in initial sorption rate with further increase in dye concentration. The linearity of the plots of the pseudo-second-order model with very high-correlation coefficients indicates that chemisorption is involved in the adsorption process. From the design of a single-batch adsorber it is predicted that the NTB-modified Kaolinite clay adsorbent will require 50% less of the adsorbent to treat certain volumes of wastewater containing 30 mg/L of Aniline blue dye when it is compared with the unmodified adsorbent. This will be cost effective in

  4. Physical and chemical properties of selected agricultural byproduct-based activated carbons and their ability to adsorb geosmin.

    PubMed

    Ng, Chilton; Losso, Jack N; Marshall, Wayne E; Rao, Ramu M

    2002-09-01

    The objectives of this study were to evaluate selected physical and chemical properties of agricultural byproduct-based activated carbons made from pecan shells and sugarcane bagasse, and compare those properties to a commercial coal-based activated carbon as well as to compare the adsorption efficiency of these carbons for geosmin. Comparison of the physical and chemical properties of pecan shell- and bagasse-based carbons to the commercial carbon, Calgon Filtrasorb 400, showed that pecan shell carbon, but not the bagasse carbon, compared favorably to Filtrasorb 400, especially in terms of surface area, bulk density, ash and attrition. A carbon dosage study done in a model system showed the amount of geosmin adsorbed to be greater for Filtrasorb 400 and the bagasse-based carbon at low carbon concentrations than for the pecan shell carbons, but geosmin adsorption was similar in all carbons at higher carbon dosages. Application of the Freundlich isotherm model to the adsorption data showed that carbons made by steam activation of pecan shells or sugarcane bagasse had geosmin adsorption characteristics most like those of the commercial carbon. In terms of physical, chemical and adsorptive properties, steam-activated pecan shell carbon most resembled the commercial carbon and has the potential to replace Filtrasorb 400 in applications involving removal of geosmin from aqueous environments.

  5. Non-Canonical and Sexually Dimorphic X Dosage Compensation States in the Mouse and Human Germline.

    PubMed

    Sangrithi, Mahesh N; Royo, Helene; Mahadevaiah, Shantha K; Ojarikre, Obah; Bhaw, Leena; Sesay, Abdul; Peters, Antoine H F M; Stadler, Michael; Turner, James M A

    2017-02-06

    Somatic X dosage compensation requires two mechanisms: X inactivation balances X gene output between males (XY) and females (XX), while X upregulation, hypothesized by Ohno and documented in vivo, balances X gene with autosomal gene output. Whether X dosage compensation occurs in germ cells is unclear. We show that mouse and human germ cells exhibit non-canonical X dosage states that differ from the soma and between the sexes. Prior to genome-wide reprogramming, X upregulation is present, consistent with Ohno's hypothesis. Subsequently, however, it is erased. In females, erasure follows loss of X inactivation, causing X dosage excess. Conversely, in males, erasure leads to permanent X dosage decompensation. Sex chromosomally abnormal models exhibit a "sex-reversed" X dosage state: XX males, like XX females, develop X dosage excess, while XO females, like XY males, develop X dosage decompensation. Thus, germline X dosage compensation states are determined by X chromosome number, not phenotypic sex. These unexpected differences in X dosage compensation states between germline and soma offer unique perspectives on sex chromosome infertility.

  6. Utility of adsorbents in the purification of drinking water: a review of characterization, efficiency and safety evaluation of various adsorbents.

    PubMed

    Dubey, Shashi Prabha; Gopal, Krishna; Bersillon, J L

    2009-05-01

    Clean drinking water is one of the implicit requisites fora healthy human population. However the growing industrialization and extensive use of chemicals for various concerns, has increased the burden of unwanted pollutants in the drinking water of developing countries like India. The entry of potentially hazardous substances into the biota has been magnifying day by day. In the absence of a possible stoppage of these, otherwise, useful chemicals, the only way to maintain safer water bodies is to develop efficient purifying technologies. One such immensely beneficial procedure that has been in use is that of purification of water using 'adsorbents'. Indigenous minerals and natural plants products have potential for removing many pollutants viz. fluoride, arsenic, nitrate, heavy metals, pesticides as well as trihalomethanes. Adsorbents which are derived from carbon, alumina, zeolite, clay minerals, iron ores, industrial by products, and natural products viz. parts of the plants, herbs and algal biomass offer promising potential of removal. In the recent years attention has been paid to develop process involving screening/pretreatment/activation/impregnation using alkalies, acids, alum, lime, manganese dioxide, ferric chloride and other chemicals which are found to enhance their adsorbing efficiency. Chemical characterization of these adsorbents recapitulates the mechanism of the process. It is imperative to observe that capacities of the adsorbents may vary depending on the characteristics, chemical modifications and concentration of the individual adsorbent. Removal kinetics is found to be based on the experimental conditions viz. pH, concentration of the adsorbate, quantity of the adsorbent and temperature. It is suggested that isotherm model is suitable tool to assess the adsorption capacities in batch and column modes. Safety evaluation and risk assessment of the process/products may be useful to provide guidelines for its sustainable disposal.

  7. Fabricating electrospun cellulose nanofibre adsorbents for ion-exchange chromatography.

    PubMed

    Dods, Stewart R; Hardick, Oliver; Stevens, Bob; Bracewell, Daniel G

    2015-01-09

    Protein separation is an integral step in biopharmaceutical manufacture with diffusion-limited packed bed chromatography remaining the default choice for industry. Rapid bind-elute separation using convective mass transfer media offers advantages in productivity by operating at high flowrates. Electrospun nanofibre adsorbents are a non-woven fibre matrix of high surface area and porosity previously investigated as a bioseparation medium. The effects of compression and bed layers, and subsequent heat treatment after electrospinning cellulose acetate nanofibres were investigated using diethylaminoethyl (DEAE) or carboxylate (COO) functionalisations. Transbed pressures were measured and compared by compression load, COO adsorbents were 30%, 70% and 90% higher than DEAE for compressions 1, 5 and 10MPa, respectively, which was attributed to the swelling effect of hydrophilic COO groups. Dynamic binding capacities (DBCs) at 10% breakthrough were measured between 2000 and 12,000CV/h (2s and 0.3s residence times) under normal binding conditions, and DBCs increased with reactant concentration from 4 to 12mgBSA/mL for DEAE and from 10 to 21mglysozyme/mL for COO adsorbents. Comparing capacities of compression loads applied after electrospinning showed that the lowest load tested, 1MPa, yielded the highest DBCs for DEAE and COO adsorbents at 20mgBSA/mL and 27mglysozyme/mL, respectively. At 1MPa, DBCs were the highest for the lowest flowrate tested but stabilised for flowrates above 2000CV/h. For compression loads of 5MPa and 10MPa, adsorbents recorded lower DBCs than 1MPa as a result of nanofibre packing and reduced surface area. Increasing the number of bed layers from 4 to 12 showed decreasing DBCs for both adsorbents. Tensile strengths were recorded to indicate the mechanical robustness of the adsorbent and be related to packing the nanofibre adsorbents in large scale configurations such as pleated cartridges. Compared with an uncompressed adsorbent, compressions of 1, 5

  8. Fabricating electrospun cellulose nanofibre adsorbents for ion-exchange chromatography

    PubMed Central

    Dods, Stewart R.; Hardick, Oliver; Stevens, Bob; Bracewell, Daniel G.

    2015-01-01

    Protein separation is an integral step in biopharmaceutical manufacture with diffusion-limited packed bed chromatography remaining the default choice for industry. Rapid bind-elute separation using convective mass transfer media offers advantages in productivity by operating at high flowrates. Electrospun nanofibre adsorbents are a non-woven fibre matrix of high surface area and porosity previously investigated as a bioseparation medium. The effects of compression and bed layers, and subsequent heat treatment after electrospinning cellulose acetate nanofibres were investigated using diethylaminoethyl (DEAE) or carboxylate (COO) functionalisations. Transbed pressures were measured and compared by compression load, COO adsorbents were 30%, 70% and 90% higher than DEAE for compressions 1, 5 and 10 MPa, respectively, which was attributed to the swelling effect of hydrophilic COO groups. Dynamic binding capacities (DBCs) at 10% breakthrough were measured between 2000 and 12,000 CV/h (2 s and 0.3 s residence times) under normal binding conditions, and DBCs increased with reactant concentration from 4 to 12 mg BSA/mL for DEAE and from 10 to 21 mg lysozyme/mL for COO adsorbents. Comparing capacities of compression loads applied after electrospinning showed that the lowest load tested, 1 MPa, yielded the highest DBCs for DEAE and COO adsorbents at 20 mg BSA/mL and 27 mg lysozyme/mL, respectively. At 1 MPa, DBCs were the highest for the lowest flowrate tested but stabilised for flowrates above 2000 CV/h. For compression loads of 5 MPa and 10 MPa, adsorbents recorded lower DBCs than 1 MPa as a result of nanofibre packing and reduced surface area. Increasing the number of bed layers from 4 to 12 showed decreasing DBCs for both adsorbents. Tensile strengths were recorded to indicate the mechanical robustness of the adsorbent and be related to packing the nanofibre adsorbents in large scale configurations such as pleated cartridges. Compared with an

  9. Elution by Le Chatelier's principle for maximum recyclability of adsorbents: applied to polyacrylamidoxime adsorbents for extraction of uranium from seawater.

    PubMed

    Oyola, Yatsandra; Vukovic, Sinisa; Dai, Sheng

    2016-05-28

    Amidoxime-based polymer adsorbents have attracted interest within the last decade due to their high adsorption capacities for uranium and other rare earth metals from seawater. The ocean contains an approximated 4-5 billion tons of uranium and even though amidoxime-based adsorbents have demonstrated the highest uranium adsorption capacities to date, they are still economically impractical because of their limited recyclability. Typically, the adsorbed metals are eluted with a dilute acid solution that not only damages the amidoxime groups (metal adsorption sites), but is also not strong enough to remove the strongly bound vanadium, which decreases the adsorption capacity with each cycle. We resolved this challenge by incorporating Le Chatelier's principle to recycle adsorbents indefinitely. We used a solution with a high concentration of amidoxime-like chelating agents, such as hydroxylamine, to desorb nearly a 100% of adsorbed metals, including vanadium, without damaging the metal adsorption sites and preserving the high adsorption capacity. The method takes advantage of knowing the binding mode between the amidoxime ligand and the metal and mimics it with chelating agents that then in a Le Chatelier's manner removes metals by shifting to a new chemical equilibrium. For this reason the method is applicable to any ligand-metal adsorbent and it will make an impact on other extraction technologies.

  10. Adjustment of Eculizumab Dosage Pattern in Patients with Atypical Hemolytic Uremic Syndrome with Suboptimal Response to Standard Treatment Pattern

    PubMed Central

    Peralta Roselló, Carmen; Baltar Martín, José María; Castillo Eraso, Lorena; de Álvaro Moreno, Fernando; Martínez Vea, Alberto; Visus-Fernández de Manzanos, María Teresa

    2016-01-01

    In patients with atypical hemolytic uremic syndrome (aHUS), complement blocking by eculizumab rapidly halts the process of thrombotic microangiopathy and it is associated with clear long-term hematologic and renal improvements. Eculizumab treatment consists of a 4-week initial phase with weekly IV administration of 900 mg doses, followed by a maintenance phase with a 1,200 mg dose in the fifth week and every 14 ± 2 days thereafter. We present three patients with aHUS and suboptimal response to eculizumab treatment at the usual administration dosage who showed hematologic and renal improvements after an adjustment in the eculizumab treatment protocol. PMID:28025630

  11. Kinetics and isotherm analysis of Tropaeoline 000 adsorption onto unsaturated polyester resin (UPR): a non-carbon adsorbent.

    PubMed

    Jain, Rajeev; Sharma, Pooja; Sikarwar, Shalini

    2013-03-01

    The presence of dyes in water is undesirable due to the toxicological impact of their entrance into the food chain. Owing to the recalcitrant nature of dyes to biological oxidation, a tertiary treatment like adsorption is required. In the present study, unsaturated polyester resin (UPR) has been used as a sorbent in the treatment of dye-contaminated water. Different concentrations of Tropaeoline 000 containing water were treated with UPR. The preliminary investigations were carried out by batch adsorption to examine the effects of pH, adsorbate concentration, adsorbent dosage, contact time, and temperature. A plausible mechanism for the ongoing adsorption process and thermodynamic parameters have also been obtained from Langmuir and Freundlich adsorption isotherm models. Thermodynamic parameter showed that the sorption process of Tropaeoline 000 onto activated carbon (AC) and UPR were feasible, spontaneous, and endothermic under studied conditions. The estimated values for (ΔG) are -10.48 × 10(3) and -6.098 × 10(3) kJ mol(-1) over AC and UPR at 303 K (30 °C), indicating towards a spontaneous process. The adsorption process followed pseudo-first-order model. The mass transfer property of the sorption process was studied using Lagergren pseudo-first-order kinetic models. The values of % removal and k (ad) for dye systems were calculated at different temperatures (303-323 K). The mechanism of the adsorption process was determined from the intraparticle diffusion model.

  12. Treatment of a simulated textile wastewater in a sequencing batch reactor (SBR) with addition of a low-cost adsorbent.

    PubMed

    Santos, Sílvia C R; Boaventura, Rui A R

    2015-06-30

    Color removal from textile wastewaters, at a low-cost and consistent technology, is even today a challenge. Simultaneous biological treatment and adsorption is a known alternative to the treatment of wastewaters containing biodegradable and non-biodegradable contaminants. The present work aims at evaluating the treatability of a simulated textile wastewater by simultaneously combining biological treatment and adsorption in a SBR (sequencing batch reactor), but using a low-cost adsorbent, instead of a commercial one. The selected adsorbent was a metal hydroxide sludge (WS) from an electroplating industry. Direct Blue 85 dye (DB) was used in the preparation of the synthetic wastewater. Firstly, adsorption kinetics and equilibrium were studied, in respect to many factors (temperature, pH, WS dosage and presence of salts and dyeing auxiliary chemicals in the aqueous media). At 25 °C and pH 4, 7 and 10, maximum DB adsorption capacities in aqueous solution were 600, 339 and 98.7 mg/g, respectively. These values are quite considerable, compared to other reported in literature, but proved to be significantly reduced by the presence of dyeing auxiliary chemicals in the wastewater. The simulated textile wastewater treatment in SBR led to BOD5 removals of 53-79%, but color removal was rather limited (10-18%). The performance was significantly enhanced by the addition of WS, with BOD5 removals above 91% and average color removals of 60-69%.

  13. Extracting Uranium from Seawater: Promising AF Series Adsorbents

    SciTech Connect

    Das, S.; Oyola, Y.; Mayes, Richard T.; Janke, Chris J.; Kuo, L. -J.; Gill, G.; Wood, J. R.; Dai, S.

    2016-04-20

    A new family of high-surface-area polyethylene fiber adsorbents named the AF series was recently developed at the Oak Ridge National Laboratory (ORNL). The AF series adsorbents were synthesized by radiation-induced graft polymerization of acrylonitrile and itaconic acid (at different monomer/comonomer mol ratios) onto high surface area polyethylene fibers. The degree of grafting (%DOG) of AF series adsorbents was found to be 154-354%. The grafted nitrile groups were converted to amidoxime groups by treating with hydroxylamine. The amidoximated adsorbents were then conditioned with 0.44 M KOH at 80 °C followed by screening at ORNL with sodium-based synthetic aqueous solution, spiked with 8 ppm uranium. The uranium adsorption capacity in simulated seawater screening ranged from 170 to 200 g-U/kg-ads irrespective of %DOG. A monomer/comonomer molar ratio in the range of 7.57-10.14 seemed to be optimum for highest uranium loading capacity. Subsequently, the adsorbents were also tested with natural seawater at Pacific Northwest National Laboratory (PNNL) using flow-through column experiments to determine uranium loading capacity with varying KOH conditioning times at 80 °C. The highest adsorption capacity of AF1 measured after 56 days of marine testing was demonstrated as 3.9 g-U/kg-adsorbent and 3.2 g-U/kg-adsorbent for 1 and 3 h of KOH conditioning at 80 °C, respectively. Based on capacity values of several AF1 samples, it was observed that changing KOH conditioning from 1 to 3 h at 80 °C resulted in a 22-27% decrease in uranium adsorption capacity in seawater.

  14. Removal of arsenic from groundwater by granular titanium dioxide adsorbent.

    PubMed

    Bang, Sunbaek; Patel, Manish; Lippincott, Lee; Meng, Xiaoguang

    2005-07-01

    A novel granular titanium dioxide (TiO2) was evaluated for the removal of arsenic from groundwater. Laboratory experiments were carried out to investigate the adsorption capacity of the adsorbent and the effect of anions on arsenic removal. Batch experimental results showed that more arsenate [As(V)] was adsorbed on TiO2 than arsenite [As(III)] in US groundwater at pH 7.0. The adsorption capacities for As(V) and As(III) were 41.4 and 32.4 mgg(-1) TiO2, respectively. However, the adsorbent had a similar adsorption capacity for As(V) and As(III) (approximately 40 mgg(-1)) when simulated Bangladesh groundwater was used. Silica (20 mgl(-1)) and phosphate (5.8 mgl(-1)) had no obvious effect on the removal of As(V) and As(III) by TiO2 at neutral pH. Point-of-entry (POE) filters containing 3 l of the granular adsorbent were tested for the removal of arsenic from groundwater in central New Jersey, USA. Groundwater was continuously passed through the filters at an empty bed contact time (EBCT) of 3 min. Approximately 45,000 bed volumes of groundwater containing an average of 39 microgl(-1) of As(V) was treated by the POE filter before the effluent arsenic concentration increased to 10 microgl(-1). The total treated water volumes per weight of adsorbent were about 60,000 l per 1 kg of adsorbent. The field filtration results demonstrated that the granular TiO2 adsorbent was very effective for the removal of arsenic in groundwater.

  15. Enhancement of therapeutic efficacy of aclarubicin against lymph node metastases using a new dosage form: aclarubicin adsorbed on activated carbon particles.

    PubMed

    Sakakura, C; Takahashi, T; Sawai, K; Hagiwara, A; Ito, M; Shobayashi, S; Sasaki, S; Ozaki, K; Shirasu, M

    1992-06-01

    Seven days after a subcutaneous inoculation of 5 x 10(5) P388 leukemia cells into the foot pad of the left hind paw of donor mouse, aclarubicin (0.2 mg/kg body weight) was injected subcutaneously into the hind paw of the opposite foot pad in the form of ACR-CH or aclarubicin aqueous solution. On day 10, the left popliteal and the lower para-aortic lymph nodes taken from each donor were transferred intraperitoneally to a normal recipient mouse. The combined survival time of recipients and the viable P388 leukemia cell number in popliteal and para-aortic lymph nodes were estimated with a calibration formula. Our results showed that the survival curve of recipients given ACR-CH was statistically improved compared with that of other treatment groups.

  16. Performance of magnetic activated carbon composite as peroxymonosulfate activator and regenerable adsorbent via sulfate radical-mediated oxidation processes.

    PubMed

    Oh, Wen-Da; Lua, Shun-Kuang; Dong, Zhili; Lim, Teik-Thye

    2015-03-02

    Magnetic activated carbon composite (CuFe2O4/AC, MACC) was prepared by a co-precipitation-calcination method. The MACC consisted of porous micro-particle morphology with homogeneously distributed CuFe2O4 and possessed high magnetic saturation moment (8.1 emu g(-1)). The performance of MACC was evaluated as catalyst and regenerable adsorbent via peroxymonosulfate (PMS, Oxone(®)) activation for methylene blue (MB) removal. Optimum CuFe2O4/AC w/w ratio was 1:1.5 giving excellent performance and can be reused for at least 3 cycles. The presence of common inorganic ions, namely Cl(-) and NO3(-) did not exert significant influence on MB degradation but humic acid decreased the MB degradation rate. As a regenerable adsorbent, negligible difference in regeneration efficiency was observed when a higher Oxone(®) dosage was employed but a better efficiency was obtained at a lower MACC loading. The factors hindering complete MACC regeneration are MB adsorption irreversibility and AC surface modification by PMS making it less favorable for subsequent MB adsorption. With an additional mild heat treatment (150 °C) after regeneration, 82% of the active sites were successfully regenerated. A kinetic model incorporating simultaneous first-order desorption, second-order adsorption and pseudo-first order degradation processes was numerically-solved to describe the rate of regeneration. The regeneration rate increased linearly with increasing Oxone(®):MACC ratio. The MACC could potentially serve as a catalyst for PMS activation and regenerable adsorbent.

  17. [Adjusting the dosage of netilmicin from two measurements. Program validation].

    PubMed

    Guedes, Y; Abgrall, J F; Lebot, M A; Voirin, T; L'Azou, D; Dheilly, M; Tanguy, R L; Le Garrec, J

    1989-01-01

    The aim of this study is to give to clinicians a well validated usefull tool allowing an increase of safety in the monitoring of netilmicin. During the first administration of the drug, two plasmatic concentrations are measured, and input in a preprogrammed hand-held calculator. A posology and a rythm of administration are returned by the calculator. After six days of this dosage regiment, the peak and the valley concentrations are compared with those previously given by the computer as values at equilibrium. No significant difference can be observed. There is no change in plasmatic creatinine level from the first to the sixth day of treatment. So, a preprogrammed hand-held computer can be convenient and safe to monitor netilmicin.

  18. A general lack of compensation for gene dosage in yeast

    PubMed Central

    Springer, Michael; Weissman, Jonathan S; Kirschner, Marc W

    2010-01-01

    Gene copy number variation has been discovered in humans, between related species, and in different cancer tissues, but it is unclear how much of this genomic-level variation leads to changes in the level of protein abundance. To address this, we eliminated one of the two genomic copies of 730 different genes in Saccharomyces cerevisiae and asked how often a 50% reduction in gene dosage leads to a 50% reduction in protein level. For at least 80% of genes tested, and under several environmental conditions, it does: protein levels in the heterozygous strain are close to 50% of wild type. For <5% of the genes tested, the protein levels in the heterozygote are maintained at nearly wild-type levels. These experiments show that protein levels are not, in general, directly monitored and adjusted to a desired level. Combined with fitness data, this implies that proteins are expressed at levels higher than necessary for survival. PMID:20461075

  19. Dosage-Dependent Modifiers of Homoeotic Mutations in Drosophila melanogaster

    PubMed Central

    Kennison, James A.; Russell, Michael A.

    1987-01-01

    The determination of segment identity in Drosophila melanogaster appears to be controlled by a small number of genes. In order to identity new components in the process, we have systematically screened the autosomal complement for loci that show a dosage-dependent interaction with mutations in previously characterized genes thought to be important in the determination of segment identity. The dominant homoeotic phenotype of mutations at four loci involved in thoracic leg determination (Pc, Pcl, Antp and Scr) were quantitated in flies bearing a series of synthetic duplications covering more than 99% of the autosomal complement. Twelve regions were identified that when present in three wild-type copies strongly enhanced or suppressed the phenotype of mutations at one or more of the four homoeotic loci examined. The effects of five of these regions appear to correspond to previously described homoeotic loci; the effects of the remaining seven appear to identify new loci involved in the determination of segment identity. PMID:17246380

  20. Dosage of intrathecal baclofen maintenance therapy in the spastic syndromes.

    PubMed

    Fares, Youssef; Khazim, Rabi M; del Barrio, E R; Burzaco, J A

    2004-01-01

    Twenty-three patients affected with severe spasticity as a result of several clinical pathologies were treated with intrathecal Baclofen and administered at a lumbar level by means of an implantable infusion system. The system allows programming of any drug dosage in a continuous infusion fashion in the subarachnoid space. The appropriate patients were selected using specific criteria and the patients were regularly reviewed regarding the level of the spasticity and functional capacity. The required daily doses were determined using a specific detailed system. The doses needed varied according to the pathologic or clinical diagnosis. The doses administered by the global method at the beginning of the treatment were 91.96 microg/day and 137.81 microg/day in the final phase. These doses were higher in patients with medullary traumatic lesion, diffuse cerebral lesion and spastic idiopathic paraparesis. Relatively mild side effects were produced by the therapeutic doses used.

  1. Biowaiver monographs for immediate release solid oral dosage forms: ibuprofen.

    PubMed

    Potthast, H; Dressman, J B; Junginger, H E; Midha, K K; Oeser, H; Shah, V P; Vogelpoel, H; Barends, D M

    2005-10-01

    Literature data are reviewed on the properties of ibuprofen related to the biopharmaceutics classification system (BCS). Ibuprofen was assessed to be a BCS class II drug. Differences in composition and/or manufacturing procedures were reported to have an effect on the rate, but not the extent of absorption; such differences are likely to be detectable by comparative in vitro dissolution tests. Also in view of its therapeutic use, its wide therapeutic index and uncomplicated pharmacokinetic properties, a biowaiver for immediate release (IR) ibuprofen solid oral drug products is scientifically justified, provided that the test product contains only those excipients reported in this paper in their usual amounts, the dosage form is rapidly dissolving (85% in 30 min or less) in buffer pH 6.8 and the test product also exhibits similar dissolution profiles to the reference product in buffer pH 1.2, 4.5, and 6.8.

  2. Biowaiver monographs for immediate release solid oral dosage forms: acetazolamide.

    PubMed

    Granero, G E; Longhi, M R; Becker, C; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M

    2008-09-01

    Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing acetazolamide are reviewed. Acetazolamide's solubility and permeability characteristics according to the Biopharmaceutics Classification System (BCS), as well as its therapeutic use and therapeutic index, its pharmacokinetic properties, data related to the possibility of excipient interactions and reported BE/bioavailability (BA) problems are taken into consideration. The available data on solubility, on oral absorption and permeability are not sufficiently conclusive to classify acetazolamide with certainty. Taking a conservative approach, no biowaiver is considered justified for the registration of new multisource drug products. However, SUPAC level 1 and level 2 postapproval changes and most EU Type I variations can be approved waiving in vivo BE studies.

  3. Biowaiver monographs for immediate release solid oral dosage forms: furosemide.

    PubMed

    Granero, G E; Longhi, M R; Mora, M J; Junginger, H E; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M

    2010-06-01

    Literature and new experimental data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing furosemide are reviewed. The available data on solubility, oral absorption, and permeability are sufficiently conclusive to classify furosemide into Class IV of the Biopharmaceutics Classification System (BCS). Furosemide's therapeutic use and therapeutic index, its pharmacokinetic properties, data related to the possibility of excipient interactions and reported BE/bioavailability (BA) problems are also taken into consideration. In view of the data available, it is concluded that the biowaiver procedure cannot be justified for either the registration of new multisource drug products or major postapproval changes (variations) to existing drug products.

  4. Biowaiver monographs for immediate release solid oral dosage forms: cimetidine.

    PubMed

    Jantratid, E; Prakongpan, S; Dressman, J B; Amidon, G L; Junginger, H E; Midha, K K; Barends, D M

    2006-05-01

    Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing cimetidine are reviewed. According to the current Biopharmaceutics Classification System (BCS), cimetidine would be assigned to Class III. Cimetidine's therapeutic use and therapeutic index, its pharmacokinetic properties, data related to the possibility of excipient interactions, and reported BE/bioavailability (BA) problems were also taken into consideration. On the basis of the overall evidence, a biowaiver can be recommended for cimetidine IR products, provided that the test product contains only those excipients reported in this paper in their usual amounts, and that the test and the comparator drug products both are "rapidly dissolving" as per BCS.

  5. Long-acting injectable hormonal dosage forms for contraception.

    PubMed

    Wu, Linfeng; Janagam, Dileep R; Mandrell, Timothy D; Johnson, James R; Lowe, Tao L

    2015-07-01

    Although great efforts have been made to develop long-acting injectable hormonal contraceptives for more than four decades, few long-acting injectable contraceptives have reached the pharmaceutical market or even entered clinical trials. On the other hand, in clinical practice there is an urgent need for injectable long-acting reversible contraceptives which can provide contraceptive protection for more than 3 months after one single injection. Availability of such products will offer great flexibility to women and resolve certain continuation issues currently occurring in clinics. Herein, we reviewed the strategies exploited in the past to develop injectable hormonal contraceptive dosages including drug microcrystal suspensions, drug-loaded microsphere suspensions and in situ forming depot systems for long-term contraception and discussed the potential solutions for remaining issues met in the previous development.

  6. Normal spastin gene dosage is specifically required for axon regeneration

    PubMed Central

    Stone, Michelle C.; Rao, Kavitha; Gheres, Kyle W.; Kim, Seahee; Tao, Juan; Rochelle, Caroline La; Folker, Christin T.; Sherwood, Nina T.; Rolls, Melissa M.

    2012-01-01

    Summary Axon regeneration allows neurons to repair circuits after trauma, but most of the molecular players remain to be identified. As microtubule rearrangements have been observed in injured neurons, we tested whether microtubule severing proteins might play a role in axon regeneration. We found that axon regeneration is extremely sensitive to levels of the microtubule severing protein spastin. While microtubule behavior in uninjured neurons was not perturbed in animals heterozygous for a spastin null allele, axon regeneration was severely disrupted in this background. Two types of axon regeneration, regeneration of an axon from a dendrite after proximal axotomy and regeneration of an axon from the stump after distal axotomy, were defective in Drosophila with one mutant copy of the spastin gene. Other types of axon and dendrite outgrowth, including regrowth of dendrites after pruning, were normal in heterozygotes. We conclude that regenerative axon growth is uniquely sensitive to spastin gene dosage. PMID:23122959

  7. Adsorption isotherms, kinetics and column operations for the removal of hazardous dye, Tartrazine from aqueous solutions using waste materials--Bottom Ash and De-Oiled Soya, as adsorbents.

    PubMed

    Mittal, Alok; Mittal, Jyoti; Kurup, Lisha

    2006-08-25

    Adsorbents, Bottom Ash (a power plant waste) and De-Oiled Soya (an agricultural waste) exhibit good efficacy to adsorb a highly toxic dye, Tartrazine. Through the batch technique equilibrium uptake of the dye is observed at different concentrations, pH of the solution, dosage of adsorbents and sieve size of adsorbents. Langmuir and Freundlich adsorption isotherms are successfully employed on both the adsorbents and on the basis of these models the thermodynamic parameters are evaluated. Kinetic investigations reveal that more than 50% adsorption of dye is achieved in about 1h in both the cases, whereas, equilibrium establishment takes about 3-4h. The linear plots obtained in rate constant and mass transfer studies further confirm the applicability of first order rate expression and mass transfer model, respectively. The kinetic data treated to identify rate controlling step of the ongoing adsorption processes indicate that for both the systems, particle diffusion process is predominant at higher concentrations, while film diffusion takes place at lower concentrations. The column studies reveal that about 96% saturation of both the columns is attained during their exhaustion, while about 88 and 84% of the dye material is recovered by eluting dilute NaOH solution through exhausted Bottom Ash and De-Oiled Soya columns, respectively.

  8. Struvite precipitation from urine with electrochemical magnesium dosage.

    PubMed

    Hug, Alexandra; Udert, Kai M

    2013-01-01

    When magnesium is added to source-separated urine, struvite (MgNH(4)PO(4)·6H(2)O) precipitates and phosphorus can be recovered. Up to now, magnesium salts have been used as the main source of magnesium. Struvite precipitation with these salts works well but is challenging in decentralized reactors, where high automation of the dosage and small reactor sizes are required. In this study, we investigated a novel approach for magnesium dosage: magnesium was electrochemically dissolved from a sacrificial magnesium electrode. We demonstrated that this process is technically simple and economically feasible and thus interesting for decentralized reactors. Linear voltammetry and batch experiments at different anode potentials revealed that the anode potential must be higher than -0.9 V vs. NHE (normal hydrogen electrode) to overcome the strong passivation of the anode. An anode potential of -0.6 V vs. NHE seemed to be suitable for active magnesium dissolution. For 13 subsequent cycles at this potential, we achieved an average phosphate removal rate of 3.7 mg P cm(-2) h(-1), a current density of 5.5 mA cm(-2) and a current efficiency of 118%. Some magnesium carbonate (nesquehonite) accumulated on the anode surface; as a consequence, the current density decreased slightly, but the current efficiency was not affected. The energy consumption for these experiments was 1.7 W h g P(-1). A cost comparison showed that sacrificial magnesium electrodes are competitive with easily soluble magnesium salts such as MgCl(2) and MgSO(4), but are more expensive than dosing with MgO. Energy costs for the electrochemical process were insignificant. Dosing magnesium electrochemically could thus be a worthwhile alternative to dosing magnesium salts. Due to the simple reactor and handling of magnesium, this may well be a particularly interesting approach for decentralized urine treatment.

  9. Biowaiver monographs for immediate release solid oral dosage forms: piroxicam.

    PubMed

    Shohin, Igor E; Kulinich, Julia I; Ramenskaya, Galina V; Abrahamsson, Bertil; Kopp, Sabine; Langguth, Peter; Polli, James E; Shah, Vinod P; Groot, D W; Barends, Dirk M; Dressman, Jennifer B

    2014-02-01

    Literature and experimental data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing piroxicam in the free acid form are reviewed. Piroxicam solubility and permeability, its therapeutic use and therapeutic index, pharmacokinetic properties, data related to the possibility of excipient interactions and reported BE/bioavailability (BA), and corresponding dissolution data are taken into consideration. The available data suggest that according to the current biopharmaceutics classification system (BCS) and all current guidances, piroxicam would be assigned to BCS Class II. The extent of piroxicam absorption seems not to depend on manufacturing conditions or excipients, so the risk of bioinequivalence in terms of area under the curve (AUC) is very low, but the rate of absorption (i.e., BE in terms of Cmax ) can be affected by the formulation. Current in vitro dissolution methods may not always reflect differences in terms of Cmax for BCS Class II weak acids; however, minor differences in absorption rate of piroxicam would not subject the patient to unacceptable risks: as piroxicam products may be taken before or after meals, the rate of absorption cannot be considered crucial to drug action. Therefore, a biowaiver for IR piroxicam solid oral dosage form is considered feasible, provided that (a) the test product contains only excipients, which are also present in IR solid oral drug products containing piroxicam, which have been approved in ICH or associated countries, for instance, those presented in Table 3 of this paper; (b) both the test and comparator drug products dissolve 85% in 30 min or less at pH 1.2, 4.5, and 6.8; and (c) the test product and comparator show dissolution profile similarity in pH 1.2, 4.5, and 6.8. When not all of these conditions can be fulfilled, BE of the products should be established in vivo.

  10. Over-the-counter pharmaceuticals: exploratory research of consumer preference toward solid oral dosage forms.

    PubMed

    Reisenwitz, T H; Wimbish, G J

    1996-01-01

    The capsule dosage form in nonprescription pharmaceuticals persists as being one of the most vulnerable to product tampering. This study examines consumer preference toward three solid oral dosage forms (capsules, caplets, and tablets) in nonprescription products. Thirteen independent variables representing dosage form attributes are measured on semantic differential scales. The data are analyzed using analysis of variance (ANOVA) and factor analysis. Implications for the pharmaceutical marketer are noted. Future directions for research are also outlined.

  11. Biliary excretion of diazepam in rats: influence of the route of administration and dosage.

    PubMed

    Phillips, R; Plaa, G L

    1981-01-01

    The biliary excretion of diazepam metabolites was found in rats. Equivalent dosages of diazepam were administered orally and intraperitoneally. The biliary excretion was dose-dependent and was greater following intraperitoneal administration. After intravenous administration, a greater percentage of the diazepam dosage administered was excreted into the bile. Repetitive intravenous administrations yielded results which approached those observed after intraperitoneally administered dosages given as a bolus.

  12. Ports Initiative

    EPA Pesticide Factsheets

    The purpose of the ports initiative is to assist EPA and other participants to formulate strategies for moving forward on actions addressing the transportation, air quality and climate issues raised in the National Conversations.

  13. Vibrational Studies of Adsorbate-Induced Reconstruction on Molybdenum Surfaces.

    NASA Astrophysics Data System (ADS)

    Lopinski, Gregory Peter

    Adsorbate-induced rearrangement of the substrate structure strongly modifies the adsorbate-substrate and adsorbate-adsorbate interactions, leading to the complex behavior observed in many chemisorption systems. In this thesis the H/Mo(211), O/Mo(211) and Na/Mo(100) systems have been studied using high resolution electron energy loss spectroscopy (HREELS) to observe vibrations of the adsorbed atoms. The vibrational data is correlated with observations of the long-range order probed by LEED as well as the work function changes induced by adsorption. Adsorbate -induced substrate reconstruction plays an important role in all three of these systems. Studies of the coadsorption systems O+H/Mo(211) and Na+O/Mo(100) indicate how these effects can influence interactions between adsorbates. For H/Mo(211), above 1ML a (1 x 1) to (1 x 2) transition is observed and attributed to modification of the substrate periodicity. Below 1ML, H atoms are bridge bonded and induce local distortions of the substrate. The transition to the (1 x 2) phase involves the ordering of these displacements and occupation of three-fold sites partially populated by conversion of the bridge bonded species. This conversion accounts for the sawtooth-like coverage dependence of the work function. The structural model proposed for this system is also supported by the desorption parameters and partial molar entropy extracted from adsorption isobars. Oxygen adsorption on Mo(211) involves the occupation of multiple binding sites, with both the long-range order and the local geometry of the adsorbate phases strongly temperature dependent. Coadsorption of low coverages of oxygen and hydrogen leads to segregation of the two adsorbates which can be understood in terms of a substrate-mediated repulsive interaction between O and H. For Na/Mo(100), the frequency of the Na-Mo symmetric stretch mode does not shift with coverage although the mode intensity is strongly coverage dependent. The absence of a frequency shift

  14. Lipid monolayers and adsorbed polyelectrolytes with different degrees of polymerization.

    PubMed

    Ortmann, Thomas; Ahrens, Heiko; Lawrenz, Frank; Gröning, Andreas; Nestler, Peter; Günther, Jens-Uwe; Helm, Christiane A

    2014-06-17

    Polystyrene sulfonate (PSS) of different molecular weight M(w) is adsorbed to oppositely charged DODAB monolayers from dilute solutions (0.01 mmol/L). PSS adsorbs flatly in a lamellar manner, as is shown by X-ray reflectivity and grazing incidence diffraction (exception: PSS with M(w) below 7 kDa adsorbs flatly disordered to the liquid expanded phase). The surface coverage and the separation of the PSS chains are independent of PSS M(w). On monolayer compression, the surface charge density increases by a factor of 2, and the separation of the PSS chains decreases by the same factor. Isotherms show that on increase of PSS M(w) the transition pressure of the LE/LC (liquid expanded/liquid condensed) phase transition decreases. When the contour length exceeds the persistence length (21 nm), the transition pressure is low and constant. For low-M(w) PSS (<7 kDa) the LE/LC transition of the lipids and the disordered/ordered transition of adsorbed PSS occur simultaneously, leading to a maximum in the contour length dependence of the transition enthalpy. These findings show that lipid monolayers at the air/water interface are a suitable model substrate with adjustable surface charge density to study the equilibrium conformation of adsorbed polyelectrolytes as well as their interactions with a model membrane.

  15. Synthesis of arsenic graft adsorbents in pilot scale

    NASA Astrophysics Data System (ADS)

    Hoshina, Hiroyuki; Kasai, Noboru; Shibata, Takuya; Aketagawa, Yasushi; Takahashi, Makikatsu; Yoshii, Akihiro; Tsunoda, Yasuhiko; Seko, Noriaki

    2012-08-01

    Synthesis of arsenic (As) adsorbents in pilot scale was carried out with a synthesizing apparatus by radiation-induced graft polymerization of 2-hydroxyethyl methacrylate phosphoric acid monomer (PA), which consists of phosphoric acid mono- (50%) and di- (50%) ethyl methacrylate esters onto a nonwoven cotton fabric (NCF), and following chemical modification by contact with a zirconium (Zr) solution. The apparatus which was equipped with reaction tanks, a washing tank and a pump can produce up to 0.3 m×14 m size of the As(V) adsorbent in one reaction. A degree of grafting of 150% was obtained at an irradiation dose of 20 kGy with 5% of PA solution mixed with deionized water for 1 h at 40 °C. Finally, after Zr(IV) was loaded onto a NCF with 5 mmol/L of Zr(IV) solution, the graft adsorbent for the removal of As(V) was achieved in pilot-scale. The adsorbent which was synthesized in pilot scale was evaluated in batch mode adsorption with 1 ppm (mg/l) of As(V) solution for 2 h at room temperature. As a result, the adsorption capacity for As(V) was 0.02 mmol/g-adsorbent.

  16. Natural material adsorbed onto a polymer to enhance immune function

    PubMed Central

    Reinaque, Ana Paula Barcelos; França, Eduardo Luzía; Scherer, Edson Fredulin; Côrtes, Mayra Aparecida; Souto, Francisco José Dutra; Honorio-França, Adenilda Cristina

    2012-01-01

    Background In this study, we produced poly(ethylene glycol) (PEG) microspheres of different sizes and adsorbing a medicinal plant mixture, and verified their effect in vitro on the viability, superoxide production, and bactericidal activity of phagocytes in the blood. Methods The medicinal plant mixture was adsorbed onto PEG microspheres and its effects were evaluated by flow cytometry and fluorescence microscopy. Results Adsorption of the herbal mixture onto the PEG microspheres was achieved and the particles were internalized by phagocytes. PEG microspheres bearing the adsorbed herbal mixture stimulated superoxide release, and activated scavenging and microbicidal activity in phagocytes. No differences in functional activity were observed when the phagocytes were not incubated with PEG microspheres bearing the adsorbed herbal mixture. Conclusion This system may be useful for the delivery of a variety of medicinal plants and can confer additional protection against infection. The data reported here suggest that a polymer adsorbed with a natural product is a treatment alternative for enhancing immune function. PMID:22956861

  17. Dynamics of adsorbed polymers on attractive homogeneous surfaces

    PubMed Central

    Yang, Qing-Hui; Luo, Meng-Bo

    2016-01-01

    Dynamic behaviors of polymer chains adsorbed on an attractive, homogeneous surface are studied by using dynamic Monte Carlo simulations. The translational diffusion coefficient Dxy parallel to the surface decreases as the intra-polymer attraction strength EPP or the polymer-surface attraction strength EPS increases. The rotational relaxation time τR increases with EPS, but the dependence of τR on EPP is dependent on the adsorption state of the polymer. We find that τR decreases with increasing EPP for a partially adsorbed polymer but it increases with EPP for a fully adsorbed polymer. Scaling relations Dxy ~ N−α and τR ~ Nβ are found for long polymers. The scaling exponent α is independent of EPS for long polymers but increases with EPP from α = 1.06 at EPP = 0. While β ≈ 2.7 is also roughly independent of EPS for the adsorbed polymer at EPP = 0, but β increases with EPS at EPP > 0. Moreover, we find that β always decreases with increasing EPP. Our results reveal different effects of the attractive surface on the diffusion and rotation of adsorbed polymers. PMID:27849002

  18. Poly(methylmethacrylate) grafted chitosan: An efficient adsorbent for anionic azo dyes.

    PubMed

    Singh, V; Sharma, A K; Tripathi, D N; Sanghi, R

    2009-01-30

    Present study reports on peroxydisulfate/ascorbic acid initiated synthesis of Chitosan-graft-poly(methylmethacrylate) (Ch-g-PMMA) and its characterization by FTIR, XRD and (13)C NMR. The copolymer remained water insoluble even under highly acidic conditions and was evaluated to be an efficient adsorbent for the three anionic azo dyes (Procion Yellow MX, Remazol Brilliant Violet and Reactive Blue H5G) over a wide pH range of 4-10 being most at pH 7. The adsorbent was also found efficient in decolorizing the textile industry wastewater and was much more efficient than the parent chitosan. Equilibrium sorption experiments were carried out at different pH and initial dye concentration values. The experimental equilibrium data for each adsorbent-dye system were successfully fitted to the Langmuir and Freundlich sorption isotherms. Based on Langmuir model Q(max) for yellow, violet and blue dyes was 250, 357 and 178, respectively. Thermodynamic parameters of the adsorption processes such as DeltaG degrees , DeltaH degrees , and DeltaS degrees were calculated. The negative values of free energy reflected the spontaneous nature of adsorption. The adsorption kinetic data of all the three dyes could be well represented by pseudo-second-order model with the correlation coefficients (R(2)) being 0.9922, 0.9997 and 0.9862, for direct yellow, reactive violet and blue dye, respectively with rate constants 0.91 x 10(-4), 1.82 x 10(-4) and 1.05 x 10(-4) g mg(-1)min(-1), respectively. At pH 7, parent chitosan also showed pseudo-second-order kinetics. The temperature dependence of dye uptake and the pseudo-second-order kinetics of the adsorption indicated that chemisorption is the rate-limiting step that controls the process.

  19. Influence of H- and OH-adsorbates on the ethanol oxidation reaction--a DEMS study.

    PubMed

    Bach Delpeuch, Antoine; Chatenet, Marian; Rau, Maria Sol; Cremers, Carsten

    2015-04-28

    The ethanol oxidation reaction (EOR) was investigated by potentiodynamic techniques on Pt/C, Rh/C, Pt-Rh/C, Pt-SnO2/C and Pt-Rh-SnO2/C by differential electrochemical mass spectrometry (DEMS) in a flow cell system. Prior to the cyclic voltammetries, adsorption of H- and OH-species was carried out by chronoamperometry at Ead = 0.05 and 1 V vs. RHE, respectively, in order to examine their influence on the EOR on the different electrocatalysts. For the sake of comparison, another adsorption potential was chosen at Ead = 0.3 V vs. RHE, in the double layer region (i.e. in the absence of such adsorbates). For this study, 20 wt% electrocatalysts were synthesized using a modified polyol method and were physically characterized by inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray diffraction (XRD) and transmission electron microscopy (TEM). When comparing the first and second cycles of the cyclic voltammograms (CVs) on Pt/C and Pt-SnO2/C, the presence of Had on the electrocatalyst surface seems to hinder the initiation of the ethanol electrooxidation, whereas the reaction onset potential is shifted negatively with the presence of OH-adsorbates. In contrast to them, the EOR on Rh/C is enhanced when the electrocatalyst surface is covered with Had and is inhibited after adsorption at Ead = 0.3 and 1 V vs. RHE. Finally, on Pt-Rh/C and Pt-Rh-SnO2/C, neither the H- nor OH-adsorbates do impact the EOR initiation. The lowest EOR onset was recorded on Pt-SnO2/C and Pt-Rh-SnO2/C electrocatalysts. The CO2 currency efficiency (CCE) was also determined for each electrocatalyst and demonstrated higher values on Pt-Rh-SnO2/C.

  20. A modified cryostat for photo-electrical characterization of porous materials in controlled atmosphere at very low gas dosage

    NASA Astrophysics Data System (ADS)

    Cultrera, Alessandro; Amato, Giampiero; Boarino, Luca; Lamberti, Carlo

    2014-08-01

    We developed an integrated system for photo-electrical characterization of materials for sensing applications in strictly controlled environment conditions. The peculiar aspect of this setup is the capability of a fine-tuned gas dosage and a fast dynamic chamber pressure control, coupled with current and voltage sensing within a modified cryostat. To illustrate the capabilities of our system we have characterised both p+-type mesoporous silicon (meso-PS) membranes and nano-crystalline mesoporous titanium dioxide (nc-TiO2) films. In particular, as a main topic is presented a well-resolved characterization of mesoporous silicon electrical conductivity changes induced by presence of ethanol. At low pore filling level adsorbate-shunted conduction is avoided, while dielectric screening effects on frozen doping centres are observable. Beside we presented observation of mesoporous titanium dioxide photo-conductivity as a function of different gas pressure reporting opposite effects of relatively low- and high-pressure regimes. High reproducibility provided by the system is discussed as a final remark.

  1. 10 CFR 35.63 - Determination of dosages of unsealed byproduct material for medical use.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) For a unit dosage, this determination must be made by— (1) Direct measurement of radioactivity; or (2... measurement of radioactivity; (2) Combination of measurement of radioactivity and mathematical...

  2. 10 CFR 35.63 - Determination of dosages of unsealed byproduct material for medical use.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...) For a unit dosage, this determination must be made by— (1) Direct measurement of radioactivity; or (2... measurement of radioactivity; (2) Combination of measurement of radioactivity and mathematical...

  3. 10 CFR 35.63 - Determination of dosages of unsealed byproduct material for medical use.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...) For a unit dosage, this determination must be made by— (1) Direct measurement of radioactivity; or (2... measurement of radioactivity; (2) Combination of measurement of radioactivity and mathematical...

  4. 10 CFR 35.63 - Determination of dosages of unsealed byproduct material for medical use.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...) For a unit dosage, this determination must be made by— (1) Direct measurement of radioactivity; or (2... measurement of radioactivity; (2) Combination of measurement of radioactivity and mathematical...

  5. 10 CFR 35.63 - Determination of dosages of unsealed byproduct material for medical use.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...) For a unit dosage, this determination must be made by— (1) Direct measurement of radioactivity; or (2... measurement of radioactivity; (2) Combination of measurement of radioactivity and mathematical...

  6. Compensation of Dosage-Sensitive Genes on the Chicken Z Chromosome

    PubMed Central

    Zimmer, Fabian; Harrison, Peter W.; Dessimoz, Christophe; Mank, Judith E.

    2016-01-01

    In many diploid species, sex determination is linked to a pair of sex chromosomes that evolved from a pair of autosomes. In these organisms, the degeneration of the sex-limited Y or W chromosome causes a reduction in gene dose in the heterogametic sex for X- or Z-linked genes. Variations in gene dose are detrimental for large chromosomal regions when they span dosage-sensitive genes, and many organisms were thought to evolve complete mechanisms of dosage compensation to mitigate this. However, the recent realization that a wide variety of organisms lack complete mechanisms of sex chromosome dosage compensation has presented a perplexing question: How do organisms with incomplete dosage compensation avoid deleterious effects of gene dose differences between the sexes? Here we use expression data from the chicken (Gallus gallus) to show that ohnologs, duplicated genes known to be dosage-sensitive, are preferentially dosage-compensated on the chicken Z chromosome. Our results indicate that even in the absence of a complete and chromosome wide dosage compensation mechanism, dosage-sensitive genes are effectively dosage compensated on the Z chromosome. PMID:27044516

  7. An immunogenicity, safety and post-marketing surveillance of a novel adsorbed human diploid cell rabies vaccine (Rabivax) in Indian subjects.

    PubMed

    Sudarshan, M K; Bhardwaj, S; Mahendra, B J; Sharma, H; Sanjay, T V; Ashwathnarayana, D H; Bilagumba, Gangaboraiah

    2008-01-01

    In 1999, Serum Institute of India indigenously developed an adsorbed human diploid cell rabies vaccine (Rabivax). During 2000-04, this new vaccine was subjected to a series of immunogenecity and safety studies. Initially, an experimental batch of Rabivax (adsorbed) was assessed on ten healthy adult volunteers and its response was comparable with that of Merieux inactivated rabies vaccine (MIRV, lyophilized) which was used as a control. Subsequently, Rabivax (adsorbed) was assessed on forty-five suspect rabid dog bite cases with MIRV as control. The vaccine was found to be equally safe and immunogenic as MIRV and showed better rabies virus neutralizing antibody (RVNA) response on day 90 than MIRV. A post-licensing study conducted on 150 cases of suspect rabid animal bites showed it to be safe and immunogenic. To assess its long-term sero-efficacy some of these subjects tested after one year of follow up showed that 84% of them had adequate RVNA titers. In addition, a routine post-marketing surveillance done on 1608 animal bite cases demonstrated that Rabivax (adsorbed) was safe and efficacious. The adverse events to Rabivax (adsorbed) included pain at injection site (3.4%), swelling with induration (2.8%), fever and headache (1.4%). No serious adverse event was reported from the studies. In conclusion, Rabivax (adsorbed) is an immunogenic, safe and efficacious vaccine for rabies prophylaxis in humans.

  8. Lotus Dust Mitigation Coating and Molecular Adsorber Coating

    NASA Technical Reports Server (NTRS)

    O'Connor, Kenneth M.; Abraham, Nithin S.

    2015-01-01

    NASA Goddard Space Flight Center has developed two unique coating formulations that will keep surfaces clean and sanitary and contain contaminants.The Lotus Dust Mitigation Coating, modeled after the self-cleaning, water-repellant lotus leaf, disallows buildup of dust, dirt, water, and more on surfaces. This coating, has been successfully tested on painted, aluminum, glass, silica, and some composite surfaces, could aid in keeping medical assets clean.The Molecular Adsorber Coating is a zeolite-based, sprayable molecular adsorber coating, designed to prevent outgassing in materials in vacuums. The coating works well to adsorb volatiles and contaminates in manufacturing and processing, such as in pharmaceutical production. The addition of a biocide would also aid in controlling bacteria levels.

  9. Method of recovering adsorbed liquid compounds from molecular sieve columns

    DOEpatents

    Burkholder, Harvey R.; Fanslow, Glenn E.

    1983-01-01

    Molecularly adsorbed volatile liquid compounds are recovered from molecular sieve adsorbent columns by directionally applying microwave energy to the bed of the adsorbent to produce a mixed liquid-gas effluent. The gas portion of the effluent generates pressure within the bed to promote the discharge of the effluent from the column bottoms. Preferably the discharged liquid-gas effluent is collected in two to three separate fractions, the second or intermediate fraction having a substantially higher concentration of the desorbed compound than the first or third fractions. The desorption does not need to be assisted by passing a carrier gas through the bed or by applying reduced pressure to the outlet from the bed.

  10. Method of recovering adsorbed liquid compounds from molecular sieve columns

    DOEpatents

    Burkholder, H.R.; Fanslow, G.E.

    1983-12-20

    Molecularly adsorbed volatile liquid compounds are recovered from molecular sieve adsorbent columns by directionally applying microwave energy to the bed of the adsorbent to produce a mixed liquid-gas effluent. The gas portion of the effluent generates pressure within the bed to promote the discharge of the effluent from the column bottoms. Preferably the discharged liquid-gas effluent is collected in two to three separate fractions, the second or intermediate fraction having a substantially higher concentration of the desorbed compound than the first or third fractions. The desorption does not need to be assisted by passing a carrier gas through the bed or by applying reduced pressure to the outlet from the bed. 8 figs.

  11. NMR study of n-dodecane adsorbed on graphite.

    PubMed

    Alba, M D; Castro, M A; Clarke, S M; Perdigón, A C

    2003-05-01

    In this brief contribution we demonstrate that 1H and 2H NMR spectroscopy can be an effective method of investigating adsorption from liquids at the solid-liquid interface. The method is illustrated here with the adsorption of a simple alkane adsorbed on graphite, in particular the system n-dodecane and graphite at coverages of 1 and 5 monolayers. Static single-pulse proton nuclear magnetic resonance and static quadrupolar echo deuterium nuclear magnetic resonance spectra were recorded for both coverages. The experimental NMR results presented here show features clearly consistent with earlier calorimetric and neutron scattering work and demonstrate the formation of solid adsorbed layers that coexist with the bulk adsorbate with both isotopes. This ability to probe both deuterated and protonated materials simultaneously illustrates that this experimental approach can be readily extended to investigate the adsorption behaviour of multicomponent mixtures.

  12. Adsorption of lead ions on composite biopolymer adsorbent

    SciTech Connect

    Seki, Hideshi; Suzuki, Akira

    1996-04-01

    A fundamental study about the application of biopolymers to the recovery of lead from dilute solution was carried out. A membranous composite biopolymer adsorbent containing two kind of biopolymers, alginic acid (AA) and humic acid (HA), was prepared. HA, which has high solubility in water, was almost completely immobilized in the adsorbent by a combination of calcium alginate gel and activated carbon powder. A general model for complexation between divalent metal ions and acidic sites on biopolymers was applied to explain the adsorption mechanism of lead on the adsorbent (HA-M). The results showed that the complexation constants and the complexation capacities of lead-AA and lead-HA systems were scarcely influenced by immobilization.

  13. ESR spectra of VO2+ ions adsorbed on calcium phosphates.

    PubMed

    Oniki, T; Doi, Y

    1983-07-01

    The ESR spectra of oxovanadium(IV) ions, (VO2+), adsorbed on hydroxyapatite(OHAp), fluorhydroxyapatite(FHAp), Mg-containing tricalcium phosphate(Mg-TCP), .octacalcium phosphate (OCP), dicalcium phosphate dihydrate (DCPD), and amorphous calcium phosphate(ACP) were measured at room temperature. The ESR parameters of VO2+ adsorbed on these compounds were slightly different from one another and accordingly, the ESR technique by use of VO2+ was useful for an analysis of the calcium phosphates precipitated from supersaturated solutions. The ESR parameters of VO2+ adsorbed on ACP and Mg-TCP were found to be very similar to each other, suggesting that ACP and TCP resemble each other in the structure of their crystal surfaces.

  14. Toward 3D graphene oxide gels based adsorbents for high-efficient water treatment via the promotion of biopolymers.

    PubMed

    Cheng, Chong Sage; Deng, Jie; Lei, Bei; He, Ai; Zhang, Xiang; Ma, Lang; Li, Shuang; Zhao, Changsheng

    2013-12-15

    Recent studies showed that graphene oxide (GO) presented high adsorption capacities to various water contaminants. However, the needed centrifugation after adsorption and the potential biological toxicity of GO restricted its applications in wastewater treatment. In this study, a facile method is provided by using biopolymers to mediate and synthesize 3D GO based gels. The obtained hybrid gels present well-defined and interconnected 3D porous network, which allows the adsorbate molecules to diffuse easily into the adsorbent. The adsorption experiments indicate that the obtained porous GO-biopolymer gels can efficiently remove cationic dyes and heavy metal ions from wastewater. Methylene blue (MB) and methyl violet (MV), two cationic dyes, are chosen as model adsorbates to investigate the adsorption capability and desorption ratio; meanwhile, the influence of contacting time, initial concentration, and pH value on the adsorption capacity of the prepared GO-biopolymer gels are also studied. The GO-biopolymer gels displayed an adsorption capacity as high as 1100 mg/g for MB dye and 1350 mg/g for MV dye, respectively. Furthermore, the adsorption kinetics and isotherms of the MB were studied in details. The experimental data of MB adsorption fitted well with the pseudo-second-order kinetic model and the Langmuir isotherm, and the results indicated that the adsorption process was controlled by the intraparticle diffusion. Moreover, the adsorption data revealed that the porous GO-biopolymer gels showed good selective adsorbability to cationic dyes and metal ions.

  15. Development of long-life-cycle tablet ceramic adsorbent for geosmin removal from water solution

    NASA Astrophysics Data System (ADS)

    Chen, Rongzhi; Xue, Qiang; Zhang, Zhenya; Sugiura, Norio; Yang, Yingnan; Li, Miao; Chen, Nan; Ying, Zhao; Lei, Zhongfang

    2011-01-01

    In this study, the tablet ceramic adsorbent (TCA), a silica/iron(III) oxide composite material, has been developed for geosmin (GSM) removal from the water solution. The physicochemical characteristics of TCA were examined with XRD, SEM, EDX and BET analyses. The sorption characteristics of GSM on TCA were investigated in a batch system. Attempts have been made to understand the adsorption kinetics, the effect of initial GSM concentration, solution pH, and reaction time. The batch experiments equilibrium data were well fitted to the Lagergren kinetic equation, which indicate the first-order nature adsorption. Over 82% of the GSM was removed by the TCA within 600 min at an initial concentration of 200 ng/L with 20 g/L of TCA dose. The batch and regeneration study indicated that the TCA is a cost-effective GSM adsorbent with sufficient mechanical strength to retain its physical integrity after long-time adsorption, and high regeneration performance for long-life-cycle application. Almost no second contamination (toxic sludge or leached iron) was observed after adsorption, and the gas resultant of thermal regeneration is harmless to atmospheric environment.

  16. Adsorbent selection for endosulfan removal from water environment.

    PubMed

    Sudhakar, Y; Dikshit, A K

    1999-01-01

    In the present study, an attempt was made to select a low cost adsorbing material for the removal of endosulfan [C,C'-(1,4,5,6,7,7-hexachloro-8,9,10- trinorborn-5-en-2,3-ylene)(dimethylsulphite)] from water. Various low cost adsorbents like wood charcoal, kimberlite tailings, silica, macro fungi sojar caju were tried with activated charcoal as reference material. The above materials were selected from various sources encompassing organic, inorganic, clayey, and biological sources. For the selection of suitable adsorbent for endosulfan uptake, maximum adsorption capacity (Qmax) was chosen as the parameter. Kinetic profiles of removal were generated for all the materials to assess the equilibrium time. Equilibrium studies were carried out for all materials to assess the adsorption equilibrium model that they followed. The model that gave the best correlation coefficient by linear regression analysis, was adopted for the calculation of Qmax of the corresponding adsorbent material. Using linearised forms of equilibrium models like Langmuir, BET, and Freundlich, maximum adsorptive capacities were determined. Activated charcoal showed the best adsorptive capacity with Qmax of 2.145 mg/g followed by wood charcoal 1.773 mg/g, sojar caju 1.575 mg/g, kimberlite tailings 0.8821 mg/g, and silica 0.3231 mg/g. Albeit activated charcoal gave better performance, it was not considered as a candidate material because of its high cost. Wood charcoal was the next best adsorbent with Qmax 1.773 mg/g. Therefore, wood charcoal was chosen as the best material for endosulfan removal. The study of physical and chemical characteristics of wood charcoal revealed that it is a potential adsorbent and can even be improved further.

  17. Experimental characterization of adsorbed protein orientation, conformation, and bioactivity

    PubMed Central

    Thyparambil, Aby A.; Wei, Yang; Latour, Robert A.

    2015-01-01

    Protein adsorption on material surfaces is a common phenomenon that is of critical importance in many biotechnological applications. The structure and function of adsorbed proteins are tightly interrelated and play a key role in the communication and interaction of the adsorbed proteins with the surrounding environment. Because the bioactive state of a protein on a surface is a function of the orientation, conformation, and accessibility of its bioactive site(s), the isolated determination of just one or two of these factors will typically not be sufficient to understand the structure–function relationships of the adsorbed layer. Rather a combination of methods is needed to address each of these factors in a synergistic manner to provide a complementary dataset to characterize and understand the bioactive state of adsorbed protein. Over the past several years, the authors have focused on the development of such a set of complementary methods to address this need. These methods include adsorbed-state circular dichroism spectropolarimetry to determine adsorption-induced changes in protein secondary structure, amino-acid labeling/mass spectrometry to assess adsorbed protein orientation and tertiary structure by monitoring adsorption-induced changes in residue solvent accessibility, and bioactivity assays to assess adsorption-induced changes in protein bioactivity. In this paper, the authors describe the methods that they have developed and/or adapted for each of these assays. The authors then provide an example of their application to characterize how adsorption-induced changes in protein structure influence the enzymatic activity of hen egg-white lysozyme on fused silica glass, high density polyethylene, and poly(methyl-methacrylate) as a set of model systems. PMID:25708632

  18. Extracting uranium from seawater: Promising AF series adsorbents

    SciTech Connect

    Das, Sadananda; Oyola, Y.; Mayes, Richard T.; Janke, Christopher James; Kuo, Li-Jung; Gill, Gary; Wood, Jordana; Dai, Sheng

    2015-11-02

    Here, a new family of high surface area polyethylene fiber adsorbents (AF series) was recently developed at the Oak Ridge National Laboratory (ORNL). The AF series of were synthesized by radiation-induced graft polymerization of acrylonitrile and itaconic acid (at different monomer/co-monomer mol ratios) onto high surface area polyethylene fibers. The degree of grafting (%DOG) of AF series adsorbents was found to be 154 354%. The grafted nitrile groups were converted to amidoxime groups by treating with hydroxylamine. The amidoximated adsorbents were then conditioned with 0.44M KOH at 80 C followed by screening at ORNL with simulated seawater spiked with 8 ppm uranium. Uranium adsorption capacity in simulated seawater screening ranged from 170-200 g-U/kg-ads irrespective of %DOG. A monomer/co-monomer mol ratio in the range of 7.57-10.14 seemed to be optimum for highest uranium loading capacity. Subsequently, the adsorbents were also tested with natural seawater at Pacific Northwest National Laboratory (PNNL) using flow-through exposure uptake experiments to determine uranium loading capacity with varying KOH conditioning time at 80 C. The highest adsorption capacity of AF1 measured after 56 days of marine testing was demonstrated as 3.9 g-U/kg-adsorbent and 3.2 g-U/kg-adsorbent for 1hr and 3hrs of KOH conditioning at 80 C, respectively. Based on capacity values of several AF1 samples, it was observed that changing KOH conditioning from 3hrs to 1hr at 80 C resulted in 22-27% increase in uranium loading capacity in seawater.

  19. Extracting uranium from seawater: Promising AF series adsorbents

    DOE PAGES

    Das, Sadananda; Oyola, Y.; Mayes, Richard T.; ...

    2015-11-02

    Here, a new family of high surface area polyethylene fiber adsorbents (AF series) was recently developed at the Oak Ridge National Laboratory (ORNL). The AF series of were synthesized by radiation-induced graft polymerization of acrylonitrile and itaconic acid (at different monomer/co-monomer mol ratios) onto high surface area polyethylene fibers. The degree of grafting (%DOG) of AF series adsorbents was found to be 154 354%. The grafted nitrile groups were converted to amidoxime groups by treating with hydroxylamine. The amidoximated adsorbents were then conditioned with 0.44M KOH at 80 C followed by screening at ORNL with simulated seawater spiked with 8more » ppm uranium. Uranium adsorption capacity in simulated seawater screening ranged from 170-200 g-U/kg-ads irrespective of %DOG. A monomer/co-monomer mol ratio in the range of 7.57-10.14 seemed to be optimum for highest uranium loading capacity. Subsequently, the adsorbents were also tested with natural seawater at Pacific Northwest National Laboratory (PNNL) using flow-through exposure uptake experiments to determine uranium loading capacity with varying KOH conditioning time at 80 C. The highest adsorption capacity of AF1 measured after 56 days of marine testing was demonstrated as 3.9 g-U/kg-adsorbent and 3.2 g-U/kg-adsorbent for 1hr and 3hrs of KOH conditioning at 80 C, respectively. Based on capacity values of several AF1 samples, it was observed that changing KOH conditioning from 3hrs to 1hr at 80 C resulted in 22-27% increase in uranium loading capacity in seawater.« less

  20. Structure and dynamics of highly adsorbed semiflexible polymer melts

    NASA Astrophysics Data System (ADS)

    Carrillo, Jan-Michael; Cheng, Shiwang; Kumar, Rajeev; Goswami, Monojoy; Sokolov, Alexie; Sumpter, Bobby

    2015-03-01

    We present a detailed analysis of coarse-grained molecular dynamics simulations of melts of semi-flexible polymer chains in the presence of an adsorbing substrate. For polymer chains located far from the substrate the chain conformations follow the worm-like chain model, in contrast to the reflected Gaussian conformation near the substrate. This is demonstrated in the chain center-of-mass distribution normal to the substrate and the probability of a polymer chain ends to be the closest to the substrate. Both quantities agree with Silberberg's derivation for an ideal chain in the presence of a reflecting wall. We characterized the adsorbed chains and counted the number of loops and tails. For stiff chains, a tail and an adsorbed segment dominate the chain conformation of the adsorbed layer. Also, the mean-square end-to-end distance normal to the substrate is proportional to the normal component of the mean-square end-to-end distance of the tails. The tails do not follow the worm-like chain model and exhibit a stretched conformation. This picture for the adsorbed layer is akin to the ``polydisperse pseudobrush'' envisioned by Guiselin. We probe the dynamics of the segments by calculating the layer (z-)resolved intermediate coherent collective dynamics structure factor, S(q,t,z), for q values equivalent to the bond length. The segment dynamics is slower for stiffer chains. In the adsorbed layer, dynamics is slowed down and can be described by two relaxation times. Department of Energy, Office of Science DE-AC05-00OR227.

  1. [Natural biopolymers as excipients in medicinal product dosage form. Part I. Soft gelatin capsules as a modern and elegant pharmaceutical dosage form].

    PubMed

    Dobrzyński, Łukasz Jerzy; Zgoda, Marian Mikołaj

    2010-01-01

    Soft gelatin capsules (Softgels) are modern and effective pharmaceutical dosage form for the administration of many medicinal products and food supplements formulations. In this short article major advantages and disadvantages of soft gelatin capsules are reviewed. Each step of manufacturing focused on fundamental techniques and requirements for developing and manufacturing technology for soft gelatin capsules is provided. Main role, characteristics, raw material, manufacturing techniques and applications in dosage form of gelatin is discussed. The review of recent advances in softgels are also included.

  2. Random registry shifts in quasi-one-dimensional adsorbate systems

    NASA Astrophysics Data System (ADS)

    Schäfer, J.; Erwin, S. C.; Hansmann, M.; Song, Z.; Rotenberg, E.; Kevan, S. D.; Hellberg, C. S.; Horn, K.

    2003-02-01

    The apparent contradiction of one-dimensional adsorbate chains on Si(111) having a 3×2 unit cell and yet a 3×1 diffraction pattern is resolved for the example of Ba/Si(111)-(3×2). Random registry shifts between adsorbate chains are observed in tunneling microscopy, with very short interchain correlation lengths. Fourier analysis provides a natural explanation for a pseudo-(3×1) diffraction pattern. Within density-functional theory such registry shifts can occur with essentially negligible energy cost, leading to entropy-driven, virtually perfect disorder. Substrate states of high symmetry and one-dimensional character are inferred to promote this phenomenon.

  3. Ordering and phase separation of adsorbed binary mixtures

    NASA Astrophysics Data System (ADS)

    Mahale, N. K.; Cole, M. W.

    1986-10-01

    The ground state energy is calculated for mixtures adsorbed on graphite and Ag surfaces. The graphite case considers noble gases adsorbed in a commensurate array, while for Ag the substrate is ignored except for its mediation of the interatomic interaction. The balance between alternative possible structures is sensitive to the assumed interaction, for which realistic potential models are employed. Comparison is made with predictions based on simple combining rules. The cases of Ar mixtures with N 2 or CO on graphite are treated, including both herringbone and pinwheel structures for the N 2. Finite temperature behavior is described qualitatively.

  4. Random registry shifts in quasi-one-dimensional adsorbate systems

    SciTech Connect

    Schafer, J.; Erwin, S.C.; Hansmann, M.; Song, Z.; Rotenberg, E.; Kevan, S.D.; Hellberg, C.S.; Horn, K.

    2003-02-18

    The apparent contradiction of one-dimensional adsorbate chains on Si(111) having a 3x2 unit cell and yet a 3x1 diffraction pattern is resolved for the example of Ba/Si(111)-(3x2). Random registry shifts between adsorbate chains are observed in tunneling microscopy, with very short interchain correlation lengths. Fourier analysis provides a natural explanation for a pseudo-(3x1) diffraction pattern. Within density-functional theory such registry shifts can occur with essentially negligible energy cost, leading to entropy-driven, virtually perfect disorder. Substrate states of high symmetry and one-dimensional character are inferred to promote this phenomenon.

  5. Structure of adsorbed organometallic rhodium: model single atom catalysts.

    PubMed

    Bennett, R A; McCavish, N D; Basham, M; Dhanak, V R; Newton, M A

    2007-02-02

    We have determined the structure of a complex rhodium carbonyl chloride [Rh(CO)2Cl] molecule adsorbed on the TiO2(110) surface by the normal incidence x-ray standing wave technique. The data show that the technique is applicable to reducible oxide systems and that the dominant adsorbed species is undissociated with Rh binding atop bridging oxygen and to the Cl found close to the fivefold coordinated Ti ions in the surface. A minority geminal dicarbonyl species, where Rh-Cl bond scission has occurred, is found bridging the bridging oxygen ions forming a high-symmetry site.

  6. Dosage optimization in positron emission tomography: state-of-the-art methods and future prospects.

    PubMed

    Karakatsanis, Nicolas A; Fokou, Eleni; Tsoumpas, Charalampos

    2015-01-01

    Positron emission tomography (PET) is widely used nowadays for tumor staging and therapy response in the clinic. However, average PET radiation exposure has increased due to higher PET utilization. This study aims to review state-of-the-art PET tracer dosage optimization methods after accounting for the effects of human body attenuation and scan protocol parameters on the counting rate. In particular, the relationship between the noise equivalent count rate (NECR) and the dosage (NECR-dosage curve) for a range of clinical PET systems and body attenuation sizes will be systematically studied to prospectively estimate the minimum dosage required for sufficiently high NECR. The optimization criterion can be determined either as a function of the peak of the NECR-dosage curve or as a fixed NECR score when NECR uniformity across a patient population is important. In addition, the systematic NECR assessments within a controllable environment of realistic simulations and phantom experiments can lead to a NECR-dosage response model, capable of predicting the optimal dosage for every individual PET scan. Unlike conventional guidelines suggesting considerably large dosage levels for obese patients, NECR-based optimization recommends: i) moderate dosage to achieve 90% of peak NECR for obese patients, ii) considerable dosage reduction for slimmer patients such that uniform NECR is attained across the patient population, and iii) prolongation of scans for PET/MR protocols, where longer PET acquisitions are affordable due to lengthy MR sequences, with motion compensation becoming important then. Finally, the need for continuous adaptation of dosage optimization to emerging technologies will be discussed.

  7. Separation of Rebaudiana A from Steviol glycoside using a polymeric adsorbent with multi-hydrogen bonding in a non-aqueous system.

    PubMed

    Ba, Jing; Zhang, Na; Yao, Lijuan; Ma, Ning; Wang, Chunhong

    2014-11-15

    Rebaudioside A (RA) and stevioside (SS) are the primary effective glycoside components in Stevia Rebaudiana. The RA glycoside is sweeter, and it tastes similarly to sucrose. Because extracts with a high RA content can be used as natural sweeteners for food additives approved by the FAO and FDA, RA should generate high market demand. In this study, an efficient method for separating RA was established based on the synergistic multi-hydrogen bonding interaction between a polymeric adsorbent and the RA glycoside. To overcome the destruction of the hydrophobic affinity required for the selective adsorption of RA, an innovative non-aqueous environment was established for adsorption and separation. To this end, an initial polymeric adsorbent composed of a glycidyl methacrylate and trimethylolpropane trimethacrylate (GMA-co-TMPTMA) copolymer matrix was synthesized, and polyethylene polyamine was employed as a functional reagent designed to react with the epoxy group on GME-co-TMPTMA to form a highly selective macroporous adsorbent. The effects of the different functional reagents and the solvent polarity on the adsorption selectivity for RA and SS, respectively, were investigated. Matching the structure of the polyethylene polyamine and sugar ligand on the glycoside molecule was essential in ensuring that the maximum synergistic interaction between adsorbent and adsorbate would be achieved. Moreover, the hydrogen-bonding force was observed to increase when the polarity of the adsorption solvent decreased. Therefore, among the synthesized macroporous polymeric adsorbents, the GTN4 adsorbent-bonding tetraethylenepentamine functional group provided the best separation in an n-butyl alcohol solution. Under the optimized gradient elution conditions, RA and SS can be effectively separated, and the contents of RA and SS increased from 33.5% and 51.5% in the initial crude extract to 95.4% and 78.2% after separation, respectively. Compared to conventional methods, the adsorption

  8. Relative Bioavailability of Scopolamine Dosage Forms and Interaction with Dextroamphetamine

    NASA Technical Reports Server (NTRS)

    Boyd, Jason L.; Du, Brian; Vaksman, Zalman; Locke, James P.; Putcha, Lakshmi

    2007-01-01

    The NASA Reduced Gravity Office (RGO) uses scopolamine (SCOP) and in combination with dextoamphetamine (DEX) to manage motion sickness symptoms during parabolic flights. The medications are dispensed as custom dosage forms as gelatin capsules. Anecdotal evidence of efficacy suggests that these formulations are unreliable and less efficacious for the treatment of motion sickness. We estimated bioavailability of four different oral formulations used by NASA for the treatment of motion sickness. Twelve healthy, non-smoking subjects between 21and 48 years of age received four treatments on separate days in a randomized fashion; the treatments were 0.8 mg SCOP alone as tablet, 0.8 mg SCOP alone in gel cap, 0.8 mg SCOP and 10 mg DEX as tablets, and 0.8 mg SCOP and 10 mg DEX in gel cap. After each treatment, blood, saliva, and urine samples were collected at scheduled time intervals for 24 h after dosing. Bioavailability and pharmacokinetic parameters were calculated and compared using ANOVA. After administration of SCOP tablets alone, maximum concentration (C(sub max)) and time for maximum concentration (t(sub max)) were 0.26 plus or minus 0.04 ng/mL and 0.71 plus or minus 0.02 h, respectively; volume of distribution, and clearance were 47.6 plus or minus 4.72 L/kg and 23.0 plus or minus 4.58 L/h/kg, respectively. SCOP t(sub max) after administration as gelcaps was significantly longer than that with tablets (1.04 h, p less than 0.05), but no significant differences in other pharmacokinetic parameters of SCOP were observed between the two dosage forms. When coadministered with DEX, the area underneath the concentration versus time curve (AUC) of SCOP was significantly reduced to 0.61 plus or minus 0.09 and 0.64 plus or minus 0.11 ng (raised dot) h/mL after administration as a tablet or gelcap formulation, respectively; SCOP C(sub max) was lower after coadministration with DEX, this difference, however, was not statistically significant. Delayed absorption with gelcaps

  9. Zirconia-silica based mesoporous desulfurization adsorbents

    NASA Astrophysics Data System (ADS)

    Palomino, Jessica M.; Tran, Dat T.; Kareh, Ana R.; Miller, Christopher A.; Gardner, Joshua M. V.; Dong, Hong; Oliver, Scott R. J.

    2015-03-01

    We report a series of mesoporous silicate sorbent materials templated by long-chain primary alkylamines that display record level of desulfurization of the jet fuel JP-8. Pure silica frameworks and those with a Si:Zr synthesis molar ratio ranging from 44:1 to 11:1 were investigated. The optimum sorbent was identified as dodecylamine-templated silica-zirconia synthesized from a gel with Si:Zr molar ratio of 15:1. With an optimized silver loading of 11 wt.%, a saturation adsorption capacity of 39.4 mgS g-1 and a silver efficiency of 1.21 molS mol Ag-1 were observed for JP-8. This sorbent displayed exceptional regenerability, maintaining 86% of its initial capacity in model fuel after solvent regeneration with diethyl ether. Low-cost, portable and reusable sorbents for the desulfurization of JP-8 jet fuel are needed to make solid oxide fuel cells (SOFCs) a reality for military power needs. SOFCs require ultra-low sulfur content fuel, which traditional desulfurization methods cannot achieve.

  10. Youth Initiatives.

    ERIC Educational Resources Information Center

    Employment and Training Administration (DOL), Washington, DC. Office of Youth Programs.

    Summarizing the first eight months of the planning, design, and implementation of the new federal youth programs created by the Youth Employment and Demonstration Projects Act of 1977 (YEDPA) and the efforts for expansion and enrichment of the Job Corps, this report explains the charters of the two projects and their initial successes in and…

  11. Conformation of adsorbed bovine serum albumin governing its desorption behavior at alumina-water interfaces.

    PubMed

    Urano, H; Fukuzaki, S

    2000-01-01

    The mode of initial adsorption of bovine serum albumin (BSA) onto positively charged Al2O3 particles was studied as a function of surface coverage (theta). The adsorption isotherm of BSA exhibited saturation (theta = 1) and the existence of an inflection point at theta of 0.82. The relative numbers of ionic groups on a BSA molecule interacting with the Al2O3 surface at various theta were monitored by measuring the relative adsorption density of H+ and OH-, ([gamma(H+) - gamma(OH-)]), for BSA-adsorbed Al2O3 using potentiometric titration. The [gamma(H+) - gamma(OH-)] curves for Al2O3, BSA, and BSA-adsorbed Al2O3 at various KNO3 concentrations showed a common intersection point (cip) which was the pH giving the acid-base equivalence point, respectively. Compared with the cip's of Al2O3 (5.6) and BSA (5.2), the cip's of BSA-adsorbed Al2O3 were situated at points corresponding to more alkaline pH values over the theta range of 0.13 to 1.0. These results suggested that negatively charged groups, mainly carboxyl groups, on the BSA molecule electrostatically interacted with the Al2O3 surface. The degree of shift in the cip increased gradually with increasing theta from 0.13 to 0.70, while it decreased markedly over the theta range of 0.82 to 1.0. The variation in the cip reflected the change in the total number of ion pairs formed between BSA molecules and Al2O3. The initial rates of BSA desorption during alkali cleaning were low and almost constant over the theta range of 0.13 to 0.70, but increased markedly at theta higher than 0.82. It is suggested that the conformational changes of BSA adsorbed on Al2O3, involving changes in the relative magnitude of electrostatic interaction forces, occur discretely at theta of approximately 0.8.

  12. Evolution of dosage compensation in Diptera: the gene maleless implements dosage compensation in Drosophila (Brachycera suborder) but its homolog in Sciara (Nematocera suborder) appears to play no role in dosage compensation.

    PubMed

    Ruiz, M F; Esteban, M R; Doñoro, C; Goday, C; Sánchez, L

    2000-12-01

    In Drosophila melanogaster and in Sciara ocellaris dosage compensation occurs by hypertranscription of the single male X chromosome. This article reports the cloning and characterization in S. ocellaris of the gene homologous to maleless (mle) of D. melanogaster, which implements dosage compensation. The Sciara mle gene produces a single transcript, encoding a helicase, which is present in both male and female larvae and adults and in testes and ovaries. Both Sciara and Drosophila MLE proteins are highly conserved. The affinity-purified antibody to D. melanogaster MLE recognizes the S. ocellaris MLE protein. In contrast to Drosophila polytene chromosomes, where MLE is preferentially associated with the male X chromosome, in Sciara MLE is found associated with all chromosomes. Anti-MLE staining of Drosophila postblastoderm male embryos revealed a single nuclear dot, whereas Sciara male and female embryos present multiple intranuclear staining spots. This expression pattern in Sciara is also observed before blastoderm stage, when dosage compensation is not yet set up. The affinity-purified antibodies against D. melanogaster MSL1, MSL3, and MOF proteins involved in dosage compensation also revealed no differences in the staining pattern between the X chromosome and the autosomes in both Sciara males and females. These results lead us to propose that different proteins in Drosophila and Sciara would implement dosage compensation.

  13. Evolution of dosage compensation in Diptera: the gene maleless implements dosage compensation in Drosophila (Brachycera suborder) but its homolog in Sciara (Nematocera suborder) appears to play no role in dosage compensation.

    PubMed Central

    Ruiz, M F; Esteban, M R; Doñoro, C; Goday, C; Sánchez, L

    2000-01-01

    In Drosophila melanogaster and in Sciara ocellaris dosage compensation occurs by hypertranscription of the single male X chromosome. This article reports the cloning and characterization in S. ocellaris of the gene homologous to maleless (mle) of D. melanogaster, which implements dosage compensation. The Sciara mle gene produces a single transcript, encoding a helicase, which is present in both male and female larvae and adults and in testes and ovaries. Both Sciara and Drosophila MLE proteins are highly conserved. The affinity-purified antibody to D. melanogaster MLE recognizes the S. ocellaris MLE protein. In contrast to Drosophila polytene chromosomes, where MLE is preferentially associated with the male X chromosome, in Sciara MLE is found associated with all chromosomes. Anti-MLE staining of Drosophila postblastoderm male embryos revealed a single nuclear dot, whereas Sciara male and female embryos present multiple intranuclear staining spots. This expression pattern in Sciara is also observed before blastoderm stage, when dosage compensation is not yet set up. The affinity-purified antibodies against D. melanogaster MSL1, MSL3, and MOF proteins involved in dosage compensation also revealed no differences in the staining pattern between the X chromosome and the autosomes in both Sciara males and females. These results lead us to propose that different proteins in Drosophila and Sciara would implement dosage compensation. PMID:11102379

  14. 21 CFR 522.1696 - Penicillin G procaine injectable dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Penicillin G procaine injectable dosage forms. 522.1696 Section 522.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... ANIMAL DRUGS § 522.1696 Penicillin G procaine injectable dosage forms....

  15. A System for Dosage-Based Functional Genomics in Poplar[OPEN

    PubMed Central

    2015-01-01

    Altering gene dosage through variation in gene copy number is a powerful approach to addressing questions regarding gene regulation, quantitative trait loci, and heterosis, but one that is not easily applied to sexually transmitted species. Elite poplar (Populus spp) varieties are created through interspecific hybridization, followed by clonal propagation. Altered gene dosage relationships are believed to contribute to hybrid performance. Clonal propagation allows for replication and maintenance of meiotically unstable ploidy or structural variants and provides an alternative approach to investigating gene dosage effects not possible in sexually propagated species. Here, we built a genome-wide structural variation system for dosage-based functional genomics and breeding of poplar. We pollinated Populus deltoides with gamma-irradiated Populus nigra pollen to produce >500 F1 seedlings containing dosage lesions in the form of deletions and insertions of chromosomal segments (indel mutations). Using high-precision dosage analysis, we detected indel mutations in ∼55% of the progeny. These indels varied in length, position, and number per individual, cumulatively tiling >99% of the genome, with an average of 10 indels per gene. Combined with future phenotype and transcriptome data, this population will provide an excellent resource for creating and characterizing dosage-based variation in poplar, including the contribution of dosage to quantitative traits and heterosis. PMID:26320226

  16. 21 CFR 524.1200 - Kanamycin ophthalmic and topical dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Kanamycin ophthalmic and topical dosage forms. 524.1200 Section 524.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... ANIMAL DRUGS § 524.1200 Kanamycin ophthalmic and topical dosage forms....

  17. 21 CFR 524.1200 - Kanamycin ophthalmic and topical dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Kanamycin ophthalmic and topical dosage forms. 524.1200 Section 524.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... ANIMAL DRUGS § 524.1200 Kanamycin ophthalmic and topical dosage forms....

  18. 21 CFR 524.1200 - Kanamycin ophthalmic and topical dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Kanamycin ophthalmic and topical dosage forms. 524.1200 Section 524.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... ANIMAL DRUGS § 524.1200 Kanamycin ophthalmic and topical dosage forms....

  19. 21 CFR 524.1200 - Kanamycin ophthalmic and topical dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Kanamycin ophthalmic and topical dosage forms. 524.1200 Section 524.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... ANIMAL DRUGS § 524.1200 Kanamycin ophthalmic and topical dosage forms....

  20. 21 CFR 524.1200 - Kanamycin ophthalmic and topical dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Kanamycin ophthalmic and topical dosage forms. 524.1200 Section 524.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... ANIMAL DRUGS § 524.1200 Kanamycin ophthalmic and topical dosage forms....

  1. 10 CFR 35.2063 - Records of dosages of unsealed byproduct material for medical use.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Records of dosages of unsealed byproduct material for medical use. 35.2063 Section 35.2063 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2063 Records of dosages of unsealed byproduct material for medical use. (a)...

  2. 10 CFR 35.2063 - Records of dosages of unsealed byproduct material for medical use.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Records of dosages of unsealed byproduct material for medical use. 35.2063 Section 35.2063 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2063 Records of dosages of unsealed byproduct material for medical use. (a)...

  3. 21 CFR 520.1802 - Piperazine-carbon disulfide complex oral dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Piperazine-carbon disulfide complex oral dosage forms. 520.1802 Section 520.1802 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1802 Piperazine-carbon disulfide complex oral dosage forms....

  4. 21 CFR 520.1802 - Piperazine-carbon disulfide complex oral dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Piperazine-carbon disulfide complex oral dosage forms. 520.1802 Section 520.1802 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1802 Piperazine-carbon disulfide complex oral dosage forms....

  5. 21 CFR 520.1802 - Piperazine-carbon disulfide complex oral dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Piperazine-carbon disulfide complex oral dosage forms. 520.1802 Section 520.1802 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1802 Piperazine-carbon disulfide complex oral dosage forms....

  6. 21 CFR 520.1802 - Piperazine-carbon disulfide complex oral dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Piperazine-carbon disulfide complex oral dosage forms. 520.1802 Section 520.1802 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1802 Piperazine-carbon disulfide complex oral dosage forms....

  7. 21 CFR 520.1802 - Piperazine-carbon disulfide complex oral dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Piperazine-carbon disulfide complex oral dosage forms. 520.1802 Section 520.1802 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.1802 Piperazine-carbon disulfide complex oral dosage forms....

  8. 21 CFR 522.1662 - Oxytetracycline hydrochloride implantation or injectable dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Oxytetracycline hydrochloride implantation or injectable dosage forms. 522.1662 Section 522.1662 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1662 Oxytetracycline hydrochloride implantation or...

  9. 21 CFR 522.90 - Ampicillin implantation and injectible dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ampicillin implantation and injectible dosage forms. 522.90 Section 522.90 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM...

  10. 76 FR 3488 - Implantation or Injectable Dosage Form New Animal Drugs; Oxytetracycline and Flunixin

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-20

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 522 Implantation or Injectable Dosage Form New... veterinary prescription use of a combination drug injectable solution containing oxytetracycline and flunixin...--IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS 0 1. The authority citation for 21 CFR part...

  11. 21 CFR 522.90 - Ampicillin implantation and injectible dosage forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ampicillin implantation and injectible dosage forms. 522.90 Section 522.90 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM...

  12. 77 FR 4227 - Implantation or Injectable Dosage Form New Animal Drugs; Gonadotropin Releasing Factor Analog...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-27

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 522 Implantation or Injectable Dosage Form New... gonadotropin releasing factor analog-diphtheria toxoid conjugate injectable solution. DATES: This rule is...: PART 522--IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS 0 1. The authority citation for...

  13. 21 CFR 522.1662 - Oxytetracycline hydrochloride implantation or injectable dosage forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Oxytetracycline hydrochloride implantation or injectable dosage forms. 522.1662 Section 522.1662 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1662 Oxytetracycline hydrochloride implantation or...

  14. 75 FR 26647 - Implantation or Injectable Dosage Form New Animal Drugs; Ivermectin

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-12

    ... CFR Part 522 [Docket No. FDA-2010-N-0002] Implantation or Injectable Dosage Form New Animal Drugs... ivermectin injectable solution in cattle and swine for treatment and control of various internal and external...--IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS 0 1. The authority citation for 21 CFR part...

  15. 21 CFR 522.2444 - Sodium thiopental implantation or injectable dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium thiopental implantation or injectable... AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.2444 Sodium thiopental implantation or injectable dosage forms....

  16. 21 CFR 522.90 - Ampicillin implantation and injectible dosage forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ampicillin implantation and injectible dosage forms. 522.90 Section 522.90 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM...

  17. 76 FR 57905 - Implantation or Injectable Dosage Form New Animal Drugs; Ivermectin

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-19

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 522 Implantation or Injectable Dosage Form New... of an ivermectin injectable solution for treatment and control of various internal and external... as follows: PART 522--IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS 0 1. The...

  18. 21 CFR 522.2444 - Sodium thiopental implantation or injectable dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium thiopental implantation or injectable... AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.2444 Sodium thiopental implantation or injectable dosage forms....

  19. 21 CFR 522.2444 - Sodium thiopental implantation or injectable dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium thiopental implantation or injectable... AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.2444 Sodium thiopental implantation or injectable dosage forms....

  20. 21 CFR 522.90 - Ampicillin implantation and injectible dosage forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ampicillin implantation and injectible dosage forms. 522.90 Section 522.90 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM...