Sample records for biological half-life

  1. Influence of sex and age on the biological half-life of cadmium in mice

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, T. (Kochi Medical School, Nangoku-shi, Japan); Suzuki, S.


    The influence of age on the whole-body biological half-life of /sup 109/Cd was studied in male mice following ip injection. The influence of sex on whole-body and organ retention was ascertained after sc injection. The whole-body biological half-life of /sup 109/Cd of the older mice was more than twice that of the younger mice, and that of the female mice was longer than that of the males. These differences demonstrate a biological difference between males and females with respect to whole-body half-life of /sup 109/Cd. The effects of age and sex on the biological half-life of Cd in mice are assessed quantitatively.

  2. Estimation of the Biological Half-Life of Methylmercury Using a Population Toxicokinetic Model

    Directory of Open Access Journals (Sweden)

    Seongil Jo


    Full Text Available Methylmercury is well known for causing adverse health effects in the brain and nervous system. Estimating the elimination constant derived from the biological half-life of methylmercury in the blood or hair is an important part of calculating guidelines for methylmercury intake. Thus, this study was conducted to estimate the biological half-life of methylmercury in Korean adults. We used a one-compartment model with a direct relationship between methylmercury concentrations in the blood and daily dietary intake of methylmercury. We quantified the between-person variability of the methylmercury half-life in the population, and informative priors were used to estimate the parameters in the model. The population half-life of methylmercury was estimated to be 80.2 ± 8.6 days. The population mean of the methylmercury half-life was 81.6 ± 8.4 days for men and 78.9 ± 8.6 days for women. The standard deviation of the half-life was estimated at 25.0 ± 8.6 days. Using the direct relationship between methylmercury concentrations in blood and methylmercury intake, the biological half-life in this study was estimated to be longer than indicated by the earlier studies that have been used to set guideline values.

  3. Biological half-life of radioactive cesium in Japanese rockfish Sebastes cheni contaminated by the Fukushima Daiichi nuclear power plant accident. (United States)

    Matsumoto, Akira; Shigeoka, Yu; Arakawa, Hisayuki; Hirakawa, Naoto; Morioka, Yoshiaki; Mizuno, Takuji


    Since the Fukushima accident in March 2011 the concentration of radioactive cesium in Japanese rockfish (Sebastes cheni) has been decreasing slower than other fish species. The aim of this study was therefore to investigate the possibility of slow elimination rate (i.e., relatively longer Tb) as one of the reasons for the slow decrease in (137)Cs concentrations in Japanese rockfish (S. cheni). To do this, we reared twenty-three individuals of this species for a period of about 1 year, during which time we measured the (137)Cs concentrations and γ-ray spectra 14 times by using a high-efficiency NaI(Tl) scintillator. We then examined the relationship between the (137)Cs concentrations and the total length of each individual. We estimated the biological half-life (Tb, day) for each individual using the total number of (137)Cs counts in the energy region, and examined the effects of total length and (137)Cs concentration on Tb by generalized linear model (GLM). We also examined the effect of sex, total length, seawater temperature, and the (137)Cs concentration of seawater on temporal changes in the (137)Cs count reduction rate by GLM. There was no clear relationship between the corrected whole-body (137)Cs concentrations and the total length in females, however there was a significant positive correlation between these two variables in males. The difference between males and females may be attributable to variation in the degree of dilution because of variable growth of individuals, and suggests that the (137)Cs concentrations of small individuals may be greatly diluted because of faster growth. However, there was no significant difference in Tb between sexes. The mean Tb (±SD) in all individuals was 269 (±39) days; this Tb value is 2.7-5.4 times longer than past Tb values (marine fish: 50-100 days), and is thought to be one of the reasons for the slower decrease in (137)Cs concentrations in this species than other fish species on the coast of Fukushima. The GLM

  4. PEPlife: A Repository of the Half-life of Peptides (United States)

    Mathur, Deepika; Prakash, Satya; Anand, Priya; Kaur, Harpreet; Agrawal, Piyush; Mehta, Ayesha; Kumar, Rajesh; Singh, Sandeep; Raghava, Gajendra P. S.


    Short half-life is one of the key challenges in the field of therapeutic peptides. Various studies have reported enhancement in the stability of peptides using methods like chemical modifications, D-amino acid substitution, cyclization, replacement of labile aminos acids, etc. In order to study this scattered data, there is a pressing need for a repository dedicated to the half-life of peptides. To fill this lacuna, we have developed PEPlife (, a manually curated resource of experimentally determined half-life of peptides. PEPlife contains 2229 entries covering 1193 unique peptides. Each entry provides detailed information of the peptide, like its name, sequence, half-life, modifications, the experimental assay for determining half-life, biological nature and activity of the peptide. We also maintain SMILES and structures of peptides. We have incorporated web-based modules to offer user-friendly data searching and browsing in the database. PEPlife integrates numerous tools to perform various types of analysis such as BLAST, Smith-Waterman algorithm, GGSEARCH, Jalview and MUSTANG. PEPlife would augment the understanding of different factors that affect the half-life of peptides like modifications, sequence, length, route of delivery of the peptide, etc. We anticipate that PEPlife will be useful for the researchers working in the area of peptide-based therapeutics.

  5. Half Life Measurements in {sup 155}Gd

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S.G.


    In the literature there exists a definite difference for the half life of the 86.5 keV level in Gd depending on whether {sup 155}Eu or {sup 155}Tb sources have been used. Using a good energy resolution electron-electron coincidence spectrometer and a {sup 155}Eu source, a half life of 6.48 {+-} 0.26 nsec was obtained for the 86.5 keV level. This is in agreement with the values previously measured with {sup 155}Tb sources. The half life of the 105.4 keV level was measured to be 1.12 {+-} 0.05 nsec.

  6. Half-life of {sup 44}Ti

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, I.; Kutschera, W.; Castagnoli, G. [Instituto di Cosmogeofisica, Torino (Italy); Paul, M. [Hebrew Univ., Jerusalem (Israel)


    The measurement of the {sup 44}Ti half-life, started 3 years ago, is still continuing. The goal of this measurement is to determine the half-life of {sup 44}Ti, which is {approximately}52 y, to a precision of {approximately}5%. An accurate value of this half-life is of interest to cosmologists who need it to determine the production of heavy elements in supernova. Three sets of samples - a pure 200-nCi {sup 44}Ti sample, a pure 300-nCi {sup 60}Co source, and a mixed {sup 44}Ti-{sup 60}Co source of similar strength - were prepared and their spectra are being measured with Ge spectrometers at Argonne, Torino and Jerusalem. Each sample is counted for a period of 2 days, at approximate intervals of 4 months. The room background is also measured for the same length of time. We hope to start data analysis at the end of summer and obtain a value for the {sup 44}Ti half-life.

  7. Half-life of 31Si

    CERN Document Server

    D'Agostino, Giancarlo; Mana, Giovanni; Oddone, Massimo


    Half-life values are widely used in nuclear chemistry to model the exponential decay of the quantified radionuclides. The analysis of existing data reveals a general lack of information on the performed experiments and an almost complete absence of uncertainty budgets. This is the situation for 31Si, the radionuclide produced via neutron capture reaction recently used to quantify trace amounts of 30Si in a sample of the silicon material highly enriched in 28Si and used for the determination of the Avogadro constant. In order to improve the quality of the now recommended 157.36(26) min value, we carried out repeated observations of the 31Si decay rate via gamma-ray spectrometry measurements. This paper reports the result we obtained, including details of the experiment and the evaluation of the uncertainty.

  8. Calculation of half-life for 79Se decay

    Institute of Scientific and Technical Information of China (English)


    The half-life for 79Se decay is calculated by using the Logf1ut systematics method. Based on the data analysis and comparison with experimental data the 79Se half-life is recommended. The scheme for 79Se decay is also shown and the radiation data are calculated in the text.

  9. Beta Decay Half-Life of 84Mo (United States)

    Stoker, J. B.; Mantica, P. F.; Bazin, D.; Bickley, A.; Becerril, A.; Crawford, H.; Cruse, K.; Estrade, A.; Mosby, M.; Guess, C. J.; Hitt, G. W.; Lorusso, G.; Matos, M.; Meharchand, R.; Minamisono, K.; Montes, F.; Pereira, J.; Perdikakis, G.; Pinter, J. S.; Schatz, H.; Vredevoogd, J.; Zegers, R. G. T.


    The β-decay half-life ^84Mo governs leakage out of the Zr-Nb cycle, a high temperature rp-process endpoint in x-ray binaries [1]. Treatment of the background and the poor statistics accumulated during the previous half-life measurement leave questions about statistical and systematic errors. We have remeasured the half-life of ^84Mo using a concerted setup of the NSCL β-Counting System [3] and 16 detectors from the Segmented Germanium Array [4]. We will report the half-life for ^84Mo, deduced using 40 times the previous sample size. The application of the NSCL RF Fragment Separator to remove unwanted isotopes, and hence reduce background for the half-life measurement, will also be discussed. [1] H. Schatz et al., Phys. Rep. 294, 167 1998 [2] P. Kienle et al., Prog. Part. Nuc. Phys. 46, 73 2001 [3] J. Prisciandaro et al., NIM A 505, 140 2003 [4] W. Mueller et al., NIM A 466, 492 2001 [5] D. Gorelov et al. PAC 2005, Knoxville, TN, May 16-20

  10. Determination of the {sup 151}Sm half-life

    Energy Technology Data Exchange (ETDEWEB)

    Be, Marie-Martine; Cassette, Philippe [CEA, LIST, Gif sur Yvette (France). LNE-Laboratoire National Henri Becquerel; Isnard, Helene [CEA-LANIE, Gif sur Yvette (France); and others


    New measurements have been undertaken to determine the half-life of {sup 151}Sm. A pure {sup 151}Sm solution was obtained after chemical separation from a samarium solution resulting from the dissolution of an irradiated samarium sample. The concentration of {sup 151}Sm in the solution was measured by mass spectrometry, combined with the isotope dilution technique. The activity of the solution was measured by liquid scintillation counting by six European laboratories as part of an international comparison. These combined results lead to a half-life of T{sub 1/2} = 94.6(6)a.

  11. Half-life predictions for decay modes of superheavy nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, S.B.; Tavares, O.A.P. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Goncalves, M. [Instituto de Radioprotecao e Dosimetria (IRD), Rio de Janeiro, RJ (Brazil); Rodriguez, O.; Guzman, F. [Instituto Superior de Ciencias e Tecnologia Nucleares (InSTEC), La Habana (Cuba); Barbosa, T.N.; Garcia, F.; Dimarco, A. [Universidade Estadual de Santa Cruz, Ilheus, BA (Brazil). Dept. de Ciencias Exatas e Tecnologicas


    We applied the Effective Liquid Drop Model (ELDM) to predict the alpha-decay, cluster emission and cold fission half-life-values of nuclei in the region of Superheavy Elements (SHE). The present calculations have been made in the region of the ZN-plane defined by 155 <=N <=220 and 110<=Z<=135. Shell effects are included via the Q-value of the corresponding decay case. We report the results of a systematic calculation of the half-life for the three nuclear decay modes in a region of the ZN-plane where superheavy elements are expected to be found. Results have shown that, among the decay modes investigated here, the alpha decay is the dominant one. i.e, the decay mode of smallest half-lives. Half-life predictions for alpha decay, cluster emission and cold fission for the isotopic family of the most recent SHE detected of Z=115 and for the isotopic family of the already consolidated SHE of Z=111 are presented. (author)

  12. Superior serum half life of albumin tagged TNF ligands

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Nicole [Division of Molecular Internal Medicine, Department of Internal Medicine II, University Hospital Wuerzburg, Roentgenring 11, 97070 Wuerzburg (Germany); Schneider, Britta; Pfizenmaier, Klaus [Institute of Cell Biology and Immunology, University of Stuttgart, Allmandring 31, 70569 Stuttgart (Germany); Wajant, Harald, E-mail: [Division of Molecular Internal Medicine, Department of Internal Medicine II, University Hospital Wuerzburg, Roentgenring 11, 97070 Wuerzburg (Germany)


    Due to their immune stimulating and apoptosis inducing properties, ligands of the TNF family attract increasing interest as therapeutic proteins. A general limitation of in vivo applications of recombinant soluble TNF ligands is their notoriously rapid clearance from circulation. To improve the serum half life of the TNF family members TNF, TWEAK and TRAIL, we genetically fused soluble variants of these molecules to human serum albumin (HSA). The serum albumin-TNF ligand fusion proteins were found to be of similar bioactivity as the corresponding HSA-less counterparts. Upon intravenous injection (i.v.), serum half life of HSA-TNF ligand fusion proteins, as determined by ELISA, was around 15 h as compared to approximately 1 h for all of the recombinant control TNF ligands without HSA domain. Moreover, serum samples collected 6 or 24 h after i.v. injection still contained high TNF ligand bioactivity, demonstrating that there is only limited degradation/inactivation of circulating HSA-TNF ligand fusion proteins in vivo. In a xenotransplantation model, significantly less of the HSA-TRAIL fusion protein compared to the respective control TRAIL protein was required to achieve inhibition of tumor growth indicating that the increased half life of HSA-TNF ligand fusion proteins translates into better therapeutic action in vivo. In conclusion, our data suggest that genetic fusion to serum albumin is a powerful and generally applicable mean to improve bioavailability and in vivo activity of TNF ligands.

  13. The half-life of {sup 18}F

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Torano, Eduardo, E-mail: e.garciatorano@ciemat.e [Ciemat, Laboratorio de Metrologia de Radiaciones Ionizantes, Avda. Complutense 22, Madrid 28040 (Spain); Medina, Virginia Peyres; Roteta Ibarra, Miguel [Ciemat, Laboratorio de Metrologia de Radiaciones Ionizantes, Avda. Complutense 22, Madrid 28040 (Spain)


    The half-life of the positron-emitter {sup 18}F has been measured by following the decay rate with three systems: ionization chambers, Ge detectors and coincidence with fast scintillators. The decay rate was measured for periods of time up to 9 half-lives. The combination of the results obtained with the three measuring systems gives a value of T{sub 1/2}=1.82871 (18) h, in good agreement with recommended data and with an estimated uncertainty lower than any other previously reported value.

  14. PEGylation of antibody fragments for half-life extension. (United States)

    Jevševar, Simona; Kusterle, Mateja; Kenig, Maja


    Antibody fragments (Fab's) represent important structure for creating new therapeutics. Compared to full antibodies Fab' fragments possess certain advantages, including higher mobility and tissue penetration, ability to bind antigen monovalently and lack of fragment crystallizable (Fc) region-mediated functions such as antibody-dependent cell mediated cytotoxicity (ADCC) or complement-dependent cytotoxicity (CDC). The main drawback for the use of Fab's in clinical applications is associated with their short half-life in vivo, which is a consequence of no longer having the Fc region. To exert meaningful clinical effects, the half-life of Fab's need to be extended, which has been achieved by postproduction chemical attachment of polyethylene glycol (PEG) chain to protein using PEGylation technology. The most suitable approach employs PEG-maleimide attachment to cysteines, either to the free hinge cysteine or to C-terminal cysteines involved in interchain disulfide linkage of the heavy and light chain. Hence, protocols for mono-PEGylation of Fab via free cysteine in the hinge region and di-PEGylation of Fab via interchain disulfide bridge are provided in this chapter.

  15. Experimental determination of the {sup 233}U half-life

    Energy Technology Data Exchange (ETDEWEB)

    Pomme, S.; Altzitzoglou, T.; Van Ammel, R.; Sibbens, G.; Eykens, R.; Richter, S.; Camps, J. [European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Geel (Belgium); Kossert, K.; Janben, H. [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany); Garcia-Torano, E.; Duran, T. [CIEMAT, Lab. de Metrologia de Radiaciones Ionizantes, Madrid (Spain); Jaubert, F. [CEA Saclay, LNE-LNHB, Lab. National Henri Becquerel 91 - Gif-sur-Yvette (France)


    The half-life of {sup 233}U was determined by a specific activity method, in the frame of an international collaboration project of four metrology institutes. A purified, highly enriched {sup 233}U solution was prepared with certified concentration of uranium isotopes. The isotopic composition of the uranium material was determined by thermal ionization mass spectrometry. The ingrowth of daughter nuclides was calculated and confirmed by {alpha}-particle and {gamma}-ray spectrometry measurements. Quantitative sources were prepared from aliquots of the {sup 233}U solution and their disintegration rate was determined by means of {alpha}-particle counting at a defined small solid angle, liquid-scintillation counting and 4{pi} counting in a pressurized proportional counter and in a CsI(Tl) sandwich spectrometer. A half-life value of 1.5867(14) * 10{sup 5} a was obtained, in which the relative standard uncertainty amounts to 0.09%. The result is lower than the currently recommended value of 1.592(2) * 10{sup 5} a and a new best estimate of T(1/2)({sup 233}U) = 1.5903(13) * 10{sup 5} a was calculated from a partially weighted mean of a set of published data. (authors)

  16. A Calorimetric Determination of the Half Life of Polonium-210 (Final Report)

    Energy Technology Data Exchange (ETDEWEB)

    Eichelberger, J. F.; Jordan, K. C.; Orr, S. R.; Parks, J. R.


    Six determinations have been made of the half life of polonium with four different steady-state, resistance-bridge calorimeters and five different samples of polonium. These six values of the half life have been weighted and combined to give a grand-mean value of the half life of 138.4005 + - 0.0051 days.

  17. sFlt Multivalent Conjugates Inhibit Angiogenesis and Improve Half-Life In Vivo (United States)

    Altiok, Eda I.; Browne, Shane; Khuc, Emily; Moran, Elizabeth P.; Qiu, Fangfang; Zhou, Kelu; Santiago-Ortiz, Jorge L.; Ma, Jian-xing; Chan, Matilda F.; Healy, Kevin E.


    Current anti-VEGF drugs for patients with diabetic retinopathy suffer from short residence time in the vitreous of the eye. In order to maintain biologically effective doses of drug for inhibiting retinal neovascularization, patients are required to receive regular monthly injections of drug, which often results in low patient compliance and progression of the disease. To improve the intravitreal residence time of anti-VEGF drugs, we have synthesized multivalent bioconjugates of an anti-VEGF protein, soluble fms-like tyrosine kinase-1 (sFlt) that is covalently grafted to chains of hyaluronic acid (HyA), conjugates that are termed mvsFlt. Using a mouse corneal angiogenesis assay, we demonstrate that covalent conjugation to HyA chains does not decrease the bioactivity of sFlt and that mvsFlt is equivalent to sFlt at inhibiting corneal angiogenesis. In a rat vitreous model, we observed that mvsFlt had significantly increased intravitreal residence time compared to the unconjugated sFlt after 2 days. The calculated intravitreal half-lives for sFlt and mvsFlt were 3.3 and 35 hours, respectively. Furthermore, we show that mvsFlt is more effective than the unconjugated form at inhibiting retinal neovascularization in an oxygen-induced retinopathy model, an effect that is most likely due to the longer half-life of mvsFlt in the vitreous. Taken together, our results indicate that conjugation of sFlt to HyA does not affect its affinity for VEGF and this conjugation significantly improves drug half-life. These in vivo results suggest that our strategy of multivalent conjugation could substantially improve upon drug half-life, and thus the efficacy of currently available drugs that are used in diseases such as diabetic retinopathy, thereby improving patient quality of life. PMID:27257918

  18. 63Ni, its half-life and standardization: revisited. (United States)

    Collé, R; Zimmerman, B E; Cassette, P; Laureano-Perez, L


    Recent liquid scintillation (LS) measurements at the National Institute of Standards and Technology (NIST) and at the Laboratoire National Henri Becquerel (LNHB) on a standardized (63)Ni solution that has been tracked for nearly 40 years have resulted in several important findings: (i) a (63)Ni half-life value of 101.2 +/- 1.5 a has been determined with the present decay data. This value is consistent with a previous specific activity determination and with an earlier value from decay measurements; and it appears to be more satisfactory than a recent data evaluator's recommended value of 98.7 a. (ii) All solution standards of (63)Ni as disseminated by NIST for the past 38(+) years are internally consistent with past and recent standardizations. (iii) Primary LS standardizations of (63)Ni by the triple-to-double coincidence ratio (TDCR) method and by CIEMAT/NIST (3)H-standard efficiency tracing (CNET) appear to be comparable, although the latter methodology is believed to be inherently inferior. (iv) There is excellent measurement agreement between NIST and LNHB for (63)Ni primary standardizations.

  19. Semi-empirical formula for spontaneous fission half life time

    Energy Technology Data Exchange (ETDEWEB)

    Santhosh, K.P., E-mail: [School of Pure and Applied Physics, Kannur University, Payyanur Campus 670 327 (India); Biju, R.K.; Sahadevan, Sabina [P G Department of Physics and Research Centre, Payyanur College, Payyanur 670 327 (India)


    A new semi-empirical formula is proposed for determining the spontaneous fission half lives, which works well for the mass region from {sup 232}Th to {sup 286}114. The computed spontaneous fission half life times are also compared with other semi-empirical formula predictions. The alpha decay half lives are systematically computed for heavy and super heavy region with proton numbers varying from 90<=Z<=122 using Coulomb and Proximity Potential Model. The comparison between computed alpha decay half lives and the present spontaneous fission semi-empirical formula predictions of even-even isotopes with Z=90-122 are studied. It is found that in super heavy region the isotopes {sup 270-274}Ds, {sup 272-278}112, {sup 272-282}114, {sup 274-292}116, {sup 276-298}118, {sup 276-308}120 and {sup 278-314}122 will survive fission and can be synthesized and identified via alpha decay.

  20. Effect of parent and daughter deformation on half-life time in exotic decay

    CERN Document Server

    Santhosh, K P


    Taking Coulomb and proximity potential as interacting barrier for post-scission region we calculated half-life time for different modes of exotic decay treating parent and fragments as spheres and these values are compared with experimental data. We studied the effect of deformation of parent and daughter on half-life time treating emitted cluster as spherical. When deformations are included half-life time values are found to decrease, though slightly. It is found that parent deformation alone will not produce appreciable change in half-life time since it affects relatively small pre-scission part of the barrier. (author)

  1. Effect of parent and daughter deformation on half-life time in exotic decay

    Indian Academy of Sciences (India)

    K P Santhosh; Antony Joseph


    Taking Coulomb and proximity potential as interacting barrier for post-scission region we calculated half-life time for different modes of exotic decay treating parent and fragments as spheres and these values are compared with experimental data. We studied the effect of deformation of parent and daughter on half-life time treating emitted cluster as spherical. When deformations are included half-life time values are found to decrease, though slightly. It is found that parent deformation alone will not produce appreciable change in half-life time since it affects relatively small pre-scission part of the barrier.

  2. Precision measurement of the half-life and the decay branches of Ga-62

    NARCIS (Netherlands)

    Canchel, G; Blank, B; Chartier, N; Delalee, F; Dendooven, P; Dossat, C; Giovinazzo, J; Huikari, J; Lalleman, AS; Jimenez, MJL; Madec, [No Value; Pedroza, JL; Penttila, H


    In an experiment performed at the Accelerator Laboratory of the University of Jyvaskyla, the beta-decay half-life of Ga-62 has been studied with high precision rising the IGISOL technique. A half-life of T-1/2 = 116.09(17) ms was nieasured. Using beta-gamma coincidences, the gamma intensity of the 9

  3. Stable isotope turnover and half-life in animal tissues: a literature synthesis. (United States)

    Vander Zanden, M Jake; Clayton, Murray K; Moody, Eric K; Solomon, Christopher T; Weidel, Brian C


    Stable isotopes of carbon, nitrogen, and sulfur are used as ecological tracers for a variety of applications, such as studies of animal migrations, energy sources, and food web pathways. Yet uncertainty relating to the time period integrated by isotopic measurement of animal tissues can confound the interpretation of isotopic data. There have been a large number of experimental isotopic diet shift studies aimed at quantifying animal tissue isotopic turnover rate λ (%·day(-1), often expressed as isotopic half-life, ln(2)/λ, days). Yet no studies have evaluated or summarized the many individual half-life estimates in an effort to both seek broad-scale patterns and characterize the degree of variability. Here, we collect previously published half-life estimates, examine how half-life is related to body size, and test for tissue- and taxa-varying allometric relationships. Half-life generally increases with animal body mass, and is longer in muscle and blood compared to plasma and internal organs. Half-life was longest in ecotherms, followed by mammals, and finally birds. For ectotherms, different taxa-tissue combinations had similar allometric slopes that generally matched predictions of metabolic theory. Half-life for ectotherms can be approximated as: ln (half-life) = 0.22*ln (body mass) + group-specific intercept; n = 261, plife can be approximated using simple allometric relationships for some taxa and tissue types, there is also a high degree of unexplained variation in our models. Our study highlights several strong and general patterns, though accurate prediction of isotopic half-life from readily available variables such as animal body mass remains elusive.

  4. Update of NIST half-life results corrected for ionization chamber source-holder instability. (United States)

    Unterweger, M P; Fitzgerald, R


    As reported at the ICRM 2011, it was discovered that the source holder used for calibrations in the NIST 4πγ ionization chamber (IC) was not stable. This has affected a large number of half-life measurement results previously reported and used in compilations of nuclear data. Corrections have been made on all of the half-life data based on the assumption that the changes to the ionization chamber response were gradual. The corrections are energy dependent and therefore radionuclide specific. This presentation will review our results and present the recommended changes in half-life values and/or uncertainties.

  5. Determination of (137)Cs half-life with an ionization chamber. (United States)

    Juget, Frédéric; Nedjadi, Youcef; Buchillier, Thierry; Bochud, François; Bailat, Claude


    The half-life of (137)Cs was measured with an ionization chamber by following the decay of 5 sources over a 30 years period between 1983 and 2013. The ratio between the ionization chamber current for the cesium sources and (226)Ra source was used for the half-life calculation. The value found for the (137)Cs half-life is 10,955.2±10.7 days, where the uncertainty evaluation combines type A and B for one standard deviation.

  6. Half-life of Si-32 from tandem-accelerator mass spectrometry (United States)

    Elmore, D.; Anantaraman, N.; Fulbright, H. W.; Gove, H. E.; Nishiizumi, K.; Murrell, M. T.; Honda, M.; Hans, H. S.


    A newly developed mass-spectrometry technique employing a tandem Van de Graaff accelerator together with a special beam-transport system and heavy-ion detector has been used to determine the half-life of Si-32. The result obtained, 108 plus or minus 18 yr, disagrees with the accepted value of 330 plus or minus 40 yr. The implications of the new half-life of Si-32, which is used for dating studies, are discussed.

  7. Using gamma distribution to determine half-life of rotenone, applied in freshwater

    Energy Technology Data Exchange (ETDEWEB)

    Rohan, Maheswaran, E-mail: [Department of Biostatistics and Epidemiology, Auckland University of Technology, Auckland (New Zealand); Fairweather, Alastair; Grainger, Natasha [Science and Capability, Department of Conservation, Hamilton (New Zealand)


    Following the use of rotenone to eradicate invasive pest fish, a dynamic first-order kinetic model is usually used to determine the half-life and rate at which rotenone dissipated from the treated waterbody. In this study, we investigate the use of a stochastic gamma model for determining the half-life and rate at which rotenone dissipates from waterbodies. The first-order kinetic and gamma models produced similar values for the half-life (4.45 days and 5.33 days respectively) and days to complete dissipation (51.2 days and 52.48 days respectively). However, the gamma model fitted the data better and was more flexible than the first-order kinetic model, allowing us to use covariates and to predict a possible range for the half-life of rotenone. These benefits are particularly important when examining the influence that different environmental factors have on rotenone dissipation and when trying to predict the rate at which rotenone will dissipate during future operations. We therefore recommend that in future the gamma distribution model is used when calculating the half-life of rotenone in preference to the dynamic first-order kinetics model. - Highlights: • We investigated the use of the gamma model to calculate the half-life of rotenone. • Physical and environmental variables can be incorporated into the model. • A method for calculating the range around a mean half-life is presented. • The model is more flexible than the traditionally used first-order kinetic model.

  8. Designing of peptides with desired half-life in intestine-like environment

    KAUST Repository

    Sharma, Arun


    Background: In past, a number of peptides have been reported to possess highly diverse properties ranging from cell penetrating, tumor homing, anticancer, anti-hypertensive, antiviral to antimicrobials. Owing to their excellent specificity, low-toxicity, rich chemical diversity and availability from natural sources, FDA has successfully approved a number of peptide-based drugs and several are in various stages of drug development. Though peptides are proven good drug candidates, their usage is still hindered mainly because of their high susceptibility towards proteases degradation. We have developed an in silico method to predict the half-life of peptides in intestine-like environment and to design better peptides having optimized physicochemical properties and half-life.Results: In this study, we have used 10mer (HL10) and 16mer (HL16) peptides dataset to develop prediction models for peptide half-life in intestine-like environment. First, SVM based models were developed on HL10 dataset which achieved maximum correlation R/R2 of 0.57/0.32, 0.68/0.46, and 0.69/0.47 using amino acid, dipeptide and tripeptide composition, respectively. Secondly, models developed on HL16 dataset showed maximum R/R2 of 0.91/0.82, 0.90/0.39, and 0.90/0.31 using amino acid, dipeptide and tripeptide composition, respectively. Furthermore, models that were developed on selected features, achieved a correlation (R) of 0.70 and 0.98 on HL10 and HL16 dataset, respectively. Preliminary analysis suggests the role of charged residue and amino acid size in peptide half-life/stability. Based on above models, we have developed a web server named HLP (Half Life Prediction), for predicting and designing peptides with desired half-life. The web server provides three facilities; i) half-life prediction, ii) physicochemical properties calculation and iii) designing mutant peptides.Conclusion: In summary, this study describes a web server \\'HLP\\' that has been developed for assisting scientific

  9. Measurement of the half-life of sup 7 sup 9 Se with PX-AMS

    CERN Document Server

    He Ming; Jiang Shan; Diao Li Jun; Wu Shao Yon; Li Chun Shen


    The half-life of sup 7 sup 9 Se has been re-measured with projectile X-rays detection (PXD) in accelerator mass spectrometry after a new PXD system had been set up in China Institute of Atomic Energy (CIAE). The PXD technique has been used for separation of sup 7 sup 9 Se from its isobar, sup 7 sup 9 Br. The detection efficiency of sup 7 sup 9 Se K subalpha X-rays is obtained from that of sup 8 sup 0 Se after energy correction. The atom number of sup 7 sup 9 Se in each sample is deduced from the measured ratios of sup 7 sup 9 Se/Se. From the measured decay rates of each sample, the half-life is deduced to be (2.80+-0.36)x10 sup 5 a. In order to check the reliability of the result of sup 7 sup 9 Se half-life, the sup 7 sup 5 Se half-life is also measured with PX-AMS method. The measured half-life of sup 7 sup 5 Se is in good agreement with well-known literature value.

  10. Re-measurement of the half-life of sup 7 sup 9 Se

    CERN Document Server

    Jiang Song Sheng; Diao Li Jun; Li Chun Shen; GouJingRu; Wu Shao Yon


    A new attempt has been made for the re-measurement of the half-life of sup 7 sup 9 Se. We made two major improvements over our earlier sup 7 sup 9 Se half-life determination (Nucl. Instr. and Meth. B 123 (1997) 403). Firstly, the half-life of sup 7 sup 9 Se was measured relative to the precisely known half-life of sup 7 sup 5 Se, rather than an absolute measurement of sup 7 sup 9 Se/Se. Secondly, the Projectile X-ray Detection technique was used for the separation of sup 7 sup 9 Se from its isobar, sup 7 sup 9 Br, rather than measuring sup 8 sup 1 Br for the deduction of sup 7 sup 9 Br interference, and this technique was also used for separation of sup 7 sup 5 Se and its isobar, sup 7 sup 5 As. A detailed description of the sample preparations, experimental setup and measurements are given. The re-measured half-life of sup 7 sup 9 Se was (2.95+-0.38)x10 sup 5 a, about a factor of 3 lower than the previous value, 1.1x10 sup 6 a. The problems in the previous measurement are discussed.

  11. 18F half-life measurement using a high-purity germanium detector. (United States)

    Han, Jubong; Lee, K B; Park, T S; Lee, J M; Oh, P J; Lee, S H; Kang, Y S; Ahn, J K


    The half-life of (18)F has been measured using HPGe detectors with a (137)Cs reference source. The counting ratio of 511 keV γ-rays from (18)F to 622 keV γ-rays from (137)Cs was fitted for the half-life with a weighted least-square method. Uncertainties due to the systematic effects arising from the measurement of a high activity (18)F source were studied in detail. The half-life of (18)F was found to be (109.72±0.19) min. The result is in a good agreement with the recommended value of (109.728±0.019) min evaluated at the Laborotaire National Henri Becquerel (LNHB).

  12. β-decay half-life of V50 calculated by the shell model (United States)

    Haaranen, M.; Srivastava, P. C.; Suhonen, J.; Zuber, K.


    In this work we survey the detectability of the β- channel of 2350V leading to the first excited 2+ state in 2450Cr. The electron-capture (EC) half-life corresponding to the transition of 2350V to the first excited 2+ state in 2250Ti had been measured earlier. Both of the mentioned transitions are 4th-forbidden non-unique. We have performed calculations of all the involved wave functions by using the nuclear shell model with the GXPF1A interaction in the full f-p shell. The computed half-life of the EC branch is in good agreement with the measured one. The predicted half-life for the β- branch is in the range ≈2×1019 yr whereas the present experimental lower limit is 1.5×1018 yr. We discuss also the experimental lay-out needed to detect the β--branch decay.

  13. Determination of the half-life of 213Fr with high precision (United States)

    Fisichella, M.; Musumarra, A.; Farinon, F.; Nociforo, C.; Del Zoppo, A.; Figuera, P.; La Cognata, M.; Pellegriti, M. G.; Scuderi, V.; Torresi, D.; Strano, E.


    High-precision measurement of half-life and Qα value of neutral and highly charged α emitters is a major subject of investigation currently. In this framework, we recently pushed half-life measurements of neutral emitters to a precision of a few per mil. This result was achieved by using different techniques and apparatuses at Istituto Nazionale di Fisica Nucleare Laboratori Nazionali del Sud (INFN-LNS) and GSI Darmstadt. Here we report on 213Fr half-life determination [T1/2(213Fr) = 34.14±0.06 s] at INFN-LNS, detailing the measurement protocol used. Direct comparison with the accepted value in the literature shows a discrepancy of more than three sigma. We propose this new value as a reference, discussing previous experiments.

  14. Three-Laboratory Measurement of the {sup 44}Ti Half-Life

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, I.; Fischer, S.M.; Kutschera, W.; Paul, M. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Bonino, G.; Bonino, G.; Castagnoli, G.C.; Castagnoli, G.C. [Dipartimento di Fisica Generale dell`Universita, Via P. Giuria 1, I-10125 Torino (Italy); Kutschera, W. [Institut fuer Radiumforschung und Kernphysik der Universitaet Wien, Boltzmanngasse 3, A-1090 Vienna (Austria); Paul, M. [Racah Institute of Physics, Hebrew University, Jerusalem, Israel 91904] [University of Chicago, Chicago, Illinois 60637 (United States)


    We report on a measurement of the {sup 44}Ti half-life aimed at lowering existing systematic uncertainties in this value, which is important to astrophysics. The half-life was measured by following the decay of {sup 44}Ti relative to {sup 60}Co for about 5yr and the measurements were performed independently in three laboratories{emdash}Argonne, Jerusalem, and Torino. We suggest to combine our result, 59.0{plus_minus}0.6yr, with the one from the accompanying Letter by G{umlt o}rres {ital et al.,} 60.3{plus_minus}1.3yr, to obtain a current {open_quotes}best value{close_quotes} for the half-life of {sup 44}Ti of 59.2{plus_minus}0.6 yr (1{sigma} error). {copyright} {ital 1998} {ital The American Physical Society}

  15. $\\beta$-Decay Half-Life of the $rp$-Process Waiting Point Nuclide $^{84}$Mo

    CERN Document Server

    Stoker, J B; Bazin, D; Becerril, A; Berryman, J S; Crawford, H L; Estrade, A; Guess, C J; Hitt, G W; Lorusso, G; Matos, M; Minamisono, K; Montes, F; Pereira, J; Perdikakis, G; Schatz, H; Smith, K; Zegers, R G T


    A half-life of 2.2 $\\pm$ 0.2 s has been deduced for the ground-state $\\beta$ decay of $^{84}$Mo, more than 1$\\sigma$ shorter than the previously adopted value. $^{84}$Mo is an even-even N = Z nucleus lying on the proton dripline, created during explosive hydrogen burning in Type I X-ray bursts in the rapid proton capture ($rp$) process. The effect of the measured half-life on $rp$-process reaction flow is explored. Implications on theoretical treatments of nuclear deformation in $^{84}$Mo are also discussed.

  16. Dual Constant Domain-Fab: A novel strategy to improve half-life and potency of a Met therapeutic antibody. (United States)

    Cignetto, Simona; Modica, Chiara; Chiriaco, Cristina; Fontani, Lara; Milla, Paola; Michieli, Paolo; Comoglio, Paolo M; Vigna, Elisa


    The kinase receptor encoded by the Met oncogene is a sensible target for cancer therapy. The chimeric monovalent Fab fragment of the DN30 monoclonal antibody (MvDN30) has an odd mechanism of action, based on cell surface removal of Met via activation of specific plasma membrane proteases. However, the short half-life of the Fab, due to its low molecular weight, is a severe limitation for the deployment in therapy. This issue was addressed by increasing the Fab molecular weight above the glomerular filtration threshold through the duplication of the constant domains, in tandem (DCD-1) or reciprocally swapped (DCD-2). The two newly engineered molecules showed biochemical properties comparable to the original MvDN30 in vitro, acting as full Met antagonists, impairing Met phosphorylation and activation of downstream signaling pathways. As a consequence, Met-mediated biological responses were inhibited, including anchorage-dependent and -independent cell growth. In vivo DCD-1 and DCD-2 showed a pharmacokinetic profile significantly improved over the original MvDN30, doubling the circulating half-life and reducing the clearance. In pre-clinical models of cancer, generated by injection of tumor cells or implant of patient-derived samples, systemic administration of the engineered molecules inhibited the growth of Met-addicted tumors.

  17. Dependence of the half-life of 221Fr on the implantation environment

    DEFF Research Database (Denmark)

    Olaizola, B.; Fraile, L.M.; Riisager, Karsten


    The possible dependence of the half-life of 221Fr on the solid-state environment has been investigated by the simultaneous measurement of implanted 221Fr ions in an insulator (Si) and a metallic substrate (Au) at the ISOLDE facility at CERN. Our results indicate that, if existing, the difference ...

  18. The half-life and exposure of cefuroxime varied in newborn infants after a Caesarean section

    DEFF Research Database (Denmark)

    Zachariassen, G.; Hyldig, N.; Joergensen, J.S.;


    Aim: No information was available on how fast intravenous cefuroxime administered to pregnant women before a Caesarean section was cleared in newborn infants. This study investigated the drug's half-life and the exposure of healthy newborn infants after their mothers received the drug. Methods....... Exposure to cefuroxime in newborn infants may influence the gut microbiota and should be investigated further....

  19. Study on Radiochemical Separation and Measurement of Half-life of ~(88)Kr

    Institute of Scientific and Technical Information of China (English)


    88Kr is one of the important gaseous fission products for determining the burn up of nuclear fuel with a short half-life, high fission yield and high branch ratio of γ-ray. Due to the more uncertainty of evaluated data and rare experimented data,

  20. 89Rb半衰期测量%Half-life Measurement of 89 Rb

    Institute of Scientific and Technical Information of China (English)

    郭晓清; 袁大庆; 徐利军; 陈克胜; 吴永乐; 郑艳明; 姚顺和


    89 Rb is an important fission product used for monitoring possible release of fission products from fuel element .The half-life is one of important nuclear parameters . The half-life of 89 Rb was determined using reference source method with two sets of HPGe detectors by place-relay way .In reference source method ,the ratio of net full-energy peak areas from the measure nuclide and the reference source was used to avoid the count correction caused by dead time and pileup .For the very short half-life of 89 Rb , the half-life iterative method was used in data analysis and the translation method was used in data unification .Finally ,the measured half-life of 89 Rb is (14.41 ± 0.04) min .%89 Rb是重要的裂变产物核素,半衰期是其一项非常重要的核参数。本文采用参考源法,运用双HPGe探头距离接续测定了89 Rb的半衰期。参考源法利用待测源和参考源的γ射线全能峰之比消除了测量过程中死时间和脉冲堆积带来的计数修正影响。由于89 Rb半衰期较短,数据分析运用了半衰期迭代法,并用平移法归一探头测量数据,最终实验测得89 Rb半衰期为(14.41±0.04) min。

  1. Matching the decay half-life with the biological half-life: ImmunoPET imaging with (44)Sc-labeled cetuximab Fab fragment. (United States)

    Chakravarty, Rubel; Goel, Shreya; Valdovinos, Hector F; Hernandez, Reinier; Hong, Hao; Nickles, Robert J; Cai, Weibo


    Scandium-44 (t1/2 = 3.9 h) is a relatively new radioisotope of potential interest for use in clinical positron emission tomography (PET). Herein, we report, for the first time, the room-temperature radiolabeling of proteins with (44)Sc for in vivo PET imaging. For this purpose, the Fab fragment of Cetuximab, a monoclonal antibody that binds with high affinity to epidermal growth factor receptor (EGFR), was generated and conjugated with N-[(R)-2-amino-3-(para-isothiocyanato-phenyl)propyl]-trans-(S,S)-cyclohexane-1,2-diamine-N,N,N',N″,N″-pentaacetic acid (CHX-A″-DTPA). The high purity of Cetuximab-Fab was confirmed by SDS-PAGE and mass spectrometry. The potential of the bioconjugate for PET imaging of EGFR expression in human glioblastoma (U87MG) tumor-bearing mice was investigated after (44)Sc labeling. PET imaging revealed rapid tumor uptake (maximum uptake of ∼12% ID/g at 4 h postinjection) of (44)Sc-CHX-A″-DTPA-Cetuximab-Fab with excellent tumor-to-background ratio, which might allow for same day PET imaging in future clinical studies. Immunofluorescence staining was conducted to correlate tracer uptake in the tumor and normal tissues with EGFR expression. This successful strategy for immunoPET imaging of EGFR expression using (44)Sc-CHX-A″-DTPA-Cetuximab-Fab can make clinically translatable advances to select the right population of patients for EGFR-targeted therapy and also to monitor the therapeutic efficacy of anti-EGFR treatments.

  2. A half-life the divided life of Bruno Pontecorvo, physicist or spy

    CERN Document Server

    Close, Frank


    Bruno Pontecorvo dedicated his career to hunting for the Higgs boson of his day: the neutrino, a nearly massless particle considered essential to the process of nuclear fission. His work on the Manhattan project under Enrico Fermi confirmed his reputation as a brilliant physicist and helped usher in the nuclear age. He should have won a Nobel Prize, but late in the summer of 1950 he vanished. At the height of the Cold War, Pontecorvo had disappeared behind the Iron Curtain. In Half-Life, physicist and historian Frank Close offers a heretofore untold history of Pontecorvo’s life, based on unprecedented access to his friends, family, and colleagues. With all the elements of a Cold War thriller—classified atomic research, an infamous double agent, a kidnapping by Soviet operatives—Half-Life is a history of particle physics at perhaps its most powerful: when it created the bomb.

  3. Precision half-life measurement of the 4-fold forbidden β decay of V50 (United States)

    Dombrowski, H.; Neumaier, S.; Zuber, K.


    A sensitive search of the 4-fold forbidden nonunique decay of V50 has been performed. A total mass measuring time product of 186 kg d has been accumulated. A reliable half-life value with the highest precision so far of (2.29±0.25)×1017 years of the electron capture decay of V50 into the first excited state of Ti50 could be obtained. A photon emission line following the β decay into the first excited state of Cr50 could not be observed, resulting in a lower limit on the half-life of the β-decay branch of 1.7×1018 years. This is not in good agreement with a claimed observation of this decay branch published in 1989.

  4. Half-life and inner penetrability in the cold fission of {sup 248}Cm

    Energy Technology Data Exchange (ETDEWEB)

    Kunhikrishnan, P.V. [Sree Narayana College, Department of Physics, Kannur (India); Santhosh, K.P. [Kannur University, School of Pure and Applied Physics, Payyanur (India); Joseph, Antony [University of Calicut, Department of Physics, Malappuram, Kerala (India)


    Using the Coulomb and proximity potential model (CPPM) with the nuclear surface tension improved by Reisdorf, the various fragmentations in the cold fission of {sup 248}Cm are studied as a cluster decay process within a fission model. The computed half-life values are compared with the values reported by Sandulescu et al. using the double-folding M3Y nuclear-nuclear potential model and are in agreement with CPPM values. The diffuseness width used in the proximity potential is found to be sensitive to the half-life. The inner penetrability is computed based on the formalism of Poenaru et al. (J. Phys. G: Nucl. Part. Phys. 17, 443 (1991)) and found that in the cold fission the contribution of the inner part (overlap region) of the barrier is significant compared to cluster decays. The variation of the inner penetrability with fragment mass is studied which emphasizes the fact that cold fission is an extension of cluster decay. (orig.)

  5. Half-life extended factor VIII for the treatment of hemophilia A. (United States)

    Tiede, A


    Prophylactic infusion of factor VIII (FVIII) prevents joint bleeding and other hemorrhages in patients with hemophilia A. Conventional FVIII concentrates have a short half-life, with an average of about 12 h in adults, ranging in individual patients between 6 and 24 h, and even shorter in younger children. Therefore, effective prophylaxis requires frequent intravenous injection, usually three times per week or every other day. Several technologies are currently under investigation to extend the half-life of FVIII, including Fc fusion (Eloctate, Elocta, efmoroctocog alfa), addition of polyethylene glycol (turoctocog alfa pegol [N8-GP], BAY 94-9027, BAX 855), and a single-chain construct (CSL627). This review summarizes characteristics of products in clinical development and discusses their potential benefits.

  6. Unified description of the proton, alpha, cluster decays and spontaneously fissions half- life

    CERN Document Server

    Mavrodiev, Strachimir Cht


    Some time ago the possibility of classical (without Gamow tunneling) universal description of radioactive nuclei decay was demonstrated. Such possibility is basis on the classical interpretation of Bohmian Psi-field reality in Bohmian-Chetaev mechanics and the hypothesis for the presence of dissipative forces, generated from the Gryzinski translational precession of the charged particles spin, in Langevin- Kramers diffusion mechanism. In this paper is present an unified model of proton, alpha decay, cluster radioactivity and spontaneous fission half-life as explicit function which depends on the total decay energy and kinetic energy, the number of protons and neutrons of daughter product, the number of protons and neutrons of mother nuclei and from a set) unknown digital parameters. The Half- lifes of the 573 nuclei taken from NuDat database together with the recent experimental data from Oganessian provide a basis for discovering the explicit form of the Kramers solution of Langevin type equation in a framew...

  7. Discussions about whether radioactive half life can be changed by mechanic motion

    Institute of Scientific and Technical Information of China (English)


    In this essay, some discussions and comments about the paper entitled "Can the decay rate of 32P be changed by mechanic motion?" (Ding et al., Science in China Series B:Chemistry (Chinese version), 2008, 38(11):1035-1037) are given. It was strongly suggested that its experimental methods, data calculations and conclusion should be reconsidered. After the data were recalculated, the new results supported that the chiral mechanic motion could induce the changes of radioactive half life.

  8. A novel exendin-4 human serum albumin fusion protein, E2HSA, with an extended half-life and good glucoregulatory effect in healthy rhesus monkeys

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ling; Wang, Lin; Meng, Zhiyun; Gan, Hui; Gu, Ruolan; Wu, Zhuona; Gao, Lei; Zhu, Xiaoxia; Sun, Wenzhong; Li, Jian; Zheng, Ying; Dou, Guifang, E-mail:


    Highlights: • E2HSA has an extended half-life and good plasma stability. • E2HSA could improve glucose-dependent insulin secretion. • E2HSA has excellent glucoregulatory effects in vivo. • E2HSA could potentially be used as a new long-acting GLP-1 receptor agonist for type 2 diabetes management. - Abstract: Glucagon-like peptide-1 (GLP-1) has attracted considerable research interest in terms of the treatment of type 2 diabetes due to their multiple glucoregulatory functions. However, the short half-life, rapid inactivation by dipeptidyl peptidase-IV (DPP-IV) and excretion, limits the therapeutic potential of the native incretin hormone. Therefore, efforts are being made to develop the long-acting incretin mimetics via modifying its structure. Here we report a novel recombinant exendin-4 human serum albumin fusion protein E2HSA with HSA molecule extends their circulatory half-life in vivo while still retaining exendin-4 biological activity and therapeutic properties. In vitro comparisons of E2HSA and exendin-4 showed similar insulinotropic activity on rat pancreatic islets and GLP-1R-dependent biological activity on RIN-m5F cells, although E2HSA was less potent than exendin-4. E2HSA had a terminal elimation half-life of approximate 54 h in healthy rhesus monkeys. Furthermore, E2HSA could reduce postprandial glucose excursion and control fasting glucose level, dose-dependent suppress food intake. Improvement in glucose-dependent insulin secretion and control serum glucose excursions were observed during hyperglycemic clamp test (18 h) and oral glucose tolerance test (42 h) respectively. Thus the improved physiological characterization of E2HSA make it a new potent anti-diabetic drug for type 2 diabetes therapy.

  9. Measurement of the Two-Neutrino Double Beta Decay Half-life of $^{130}$Te with the CUORE-0 Experiment

    CERN Document Server

    Alduino, C; Artusa, D R; Avignone, F T; Azzolini, O; Banks, T I; Bari, G; Beeman, J W; Bellini, F; Bersani, A; Biassoni, M; Branca, A; Brofferio, C; Bucci, C; Camacho, A; Caminata, A; Canonica, L; Cao, X G; Capelli, S; Cappelli, L; Carbone, L; Cardani, L; Carniti, P; Casali, N; Cassina, L; Chiesa, D; Chott, N; Clemenza, M; Copello, S; Cosmelli, C; Cremonesi, O; Creswick, R J; Cushman, J S; D'Addabbo, A; Dafinei, I; Davis, C J; Dell'Oro, S; Deninno, M M; Di Domizio, S; Di Vacri, M L; Drobizhev, A; Fang, D Q; Faverzani, M; Fernandes, G; Ferri, E; Ferroni, F; Fiorini, E; Franceschi, M A; Freedman, S J; Fujikawa, B K; Giachero, A; Gironi, L; Giuliani, A; Gladstone, L; Gorla, P; Gotti, C; Gutierrez, T D; Haller, E E; Han, K; Hansen, E; Heeger, K M; Hennings-Yeomans, R; Hickerson, K P; Huang, H Z; Kadel, R; Keppel, G; Kolomensky, Yu G; Leder, A; Ligi, C; Lim, K E; Liu, X; Ma, Y G; Maino, M; Marini, L; Martinez, M; Maruyama, R H; Mei, Y; Moggi, N; Morganti, S; Mosteiro, P J; Napolitano, T; Nones, C; Norman, E B; Nucciotti, A; O'Donnell, T; Orio, F; Ouellet, J L; Pagliarone, C E; Pallavicini, M; Palmieri, V; Pattavina, L; Pavan, M; Pessina, G; Pettinacci, V; Piperno, G; Pira, C; Pirro, S; Pozzi, S; Previtali, E; Rosenfeld, C; Rusconi, C; Sangiorgio, S; Santone, D; Scielzo, N D; Singh, V; Sisti, M; Smith, A R; Taffarello, L; Tenconi, M; Terranova, F; Tomei, C; Trentalange, S; Vignati, M; Wagaarachchi, S L; Wang, B S; Wang, H W; Wilson, J; Winslow, L A; Wise, T; Woodcraft, A; Zanotti, L; Zhang, G Q; Zhu, B X; Zimmermann, S; Zucchelli, S


    We report on the measurement of the two-neutrino double beta decay half-life of $^{130}$Te with the CUORE-0 detector. From an exposure of 33.4 kg$\\cdot$y of TeO$_2$, the half-life is determined to be $T_{1/2}^{2\

  10. A novel method to determine the half-life of 32Si (United States)

    Schnabel, C.; Beer, J.; Clausen, H. B.


    A novel method using high-resolution 10Be concentrations to correct 32Si data from independently dated depth profiles is presented. It is demonstrated that by correcting 32Si deposition rates for temporal changes based on production rate fluctuations the derived half-life of 32Si agrees with half-life determinations based on physical measurements of artificial samples. Currently, the half-life of 32Si is not accurately known. Moreover, results from physical measurements of artificial samples yielded much shorter half-lives (100-172 yr) than results based on depth profiles. For depth profiles most results were between 250 and 300 yr (Clausen, 1973), with the exception of a relatively recent work on a varved lake sediment which resulted in 178 yr (Nijampurkar et al., 1998). Using high-resolution 10Be concentrations from the Dye3 ice-core each data point of the Northern hemisphere ice-core 32Si concentrations is corrected for temporal variations in deposition rate. This means that we assume that temporal variations in 32Si and 10Be deposition are identical instead of using the assumption of constant deposition rates that resulted in the long half-lives. In the case of the varved lake sediment, 32Si/Si ratios are corrected in the same way as 32Si concentrations for the ice cores. We present our results that half-lives of longer than 180 yr can be ruled out for 32Si and propose using 10Be and 32Si concentrations from the same samples of independently dated profiles as a new method to apply 32Si for dating purposes. Preliminary results have been presented at the QRA meeting in Glasgow 2006 {schnabel et al., 2006]. HB Clausen, Journal of Glaciology 12 (1973) 411. VN Nijampurkar et al., Earth and Planetary Science Letters 163 (1998) 191. C. Schnabel, J. Beer, HB Clausen, QRA annual discussion meeting Glasgow, 2006.

  11. Determination of the half-life of sup 1 sup 0 sup 5 sup m Rh

    CERN Document Server

    Kronenberg, A K; Weber, R; Esterlund, R A; Patzelt, P


    Following a fast chemical separation of Ru isotopes from a fission-product mixture, sup 1 sup 0 sup 5 sup m Rh was periodically extracted from its precursor (4.44-h sup 1 sup 0 sup 5 Ru) for measurements of its half-life. The new value for the T sub 1 sub / sub 2 of sup 1 sup 0 sup 5 sup m Rh of (43.0+-0.3) s resolves the long-standing conflict in the literature between the two earlier measured values of 45 and 30 s.

  12. Safety and Efficacy of BAY 94-9027, a Prolonged-Half-Life Factor VIII

    DEFF Research Database (Denmark)

    Reding, M T; Ng, H J; Poulsen, Lone Hvitfeldt


    BACKGROUND: BAY 94-9027 is a B-domain-deleted prolonged-half-life recombinant factor VIII (FVIII) conjugates in a site-specific manner with polyethylene glycol. OBJECTIVE: Assess efficacy and safety of BAY 94-9027 for prophylaxis and treatment of bleeds in patients with severe hemophilia A PATIENTS.......0;4.3). 636/702 bleeds (90.6%) were controlled with ≤2 infusions. No patient developed a FVIII inhibitor. CONCLUSIONS: BAY 94-9027 prevented bleeding across 3 individually tailored dose regimens and was effective for treatment of bleeds. This article is protected by copyright. All rights reserved....

  13. Gamma-spectrometric determination of the sup 8 sup 9 Sr isotope half-life

    CERN Document Server

    Popov, Y S; Markushin, M N; Kupriyanov, V N; Timofeev, G A


    Using the method of semiconductor [Ge(Li)-detector] gamma-spectroscopy by the results of measurements of 913 keV ( sup 8 sup 9 Sr) gamma-line intensity for 6000 h, using as internal reference the 661.7 keV ( sup 1 sup 3 sup 7 Cs) gamma-line, the value of sup 8 sup 9 Sr isotope half-life has been calculated, which proved to be 1208+-9 h or 50.34+-0.37 days. Error is provided for confidential probability P = 0.95

  14. The Half Life of the 53 keV Level in {sup 197}Pt

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S.G.


    The half life of the recently proposed 53 keV level in {sup 197}Pt has been measured to 18.5 {+-} 1.5 nsec using the delayed coincidence technique. This level, which is identified with the f{sub 5/2} single particle state, decays directly to the p{sub 1/2} ground state in {sup 197}Pt. The reduced E2 transition probability for this 53 keV transition has been deduced and compared with the results obtained for the corresponding transitions in other Pt, Hg, and Pb isotopes and with the theoretical predictions by Sorensen and by Wahlborn and Martinson.

  15. Precise Half-Life Measurement of the Superallowed Beta+ Emitter 46V

    CERN Document Server

    Park, H I; Iacob, V E; Chen, L; Goodwin, J; Nica, N; Simmons, E; Trache, L; Tribble, R E


    The half-life of 46V has been measured to be 422.66(6) ms, which is a factor of two more precise than the best previous measurement. Our result is also consistent with the previous measurements, with no repeat of the disagreement recently encountered with Q_{EC} values measured for the same transition. The Ft value for the 46V superallowed transition, incorporating all world data, is determined to be 3074.1(26) s, a result consistent with the average Ft value of 3072.08(79) s established from the 13 best-known superallowed transitions.

  16. The evolution of drug-resistant malaria: the role of drug elimination half-life.


    Hastings, Ian M.; Watkins, William M; White, Nicholas J


    This paper seeks to define and quantify the influence of drug elimination half-life on the evolution of antimalarial drug resistance. There are assumed to be three general classes of susceptibility of the malaria parasite Plasmodium falciparum to a drug: Res0, the original, susceptible wildtype; Res1, a group of intermediate levels of susceptibility that are more tolerant of the drug but still cleared by treatment; and Res2, which is completely resistant to the drug. Res1 and Res2 resistance ...

  17. Measurement of the half-life of sup 1 sup 7 sup 6 Lu

    CERN Document Server

    Nir-El, Y


    The half-life of sup 1 sup 7 sup 6 Lu was determined by measuring the disintegration rate of a solution of lutetium oxide, using a calibrated HPGe detector, and found to be (3.69+-0.02)x10 sup 1 sup 0 y. It is recommended that the current adopted value be calculated from the grouping of three published values since 1983, including our value, the weighted mean of which is (3.73+-0.01)x10 sup 1 sup 0 y.

  18. Calculation of the Aluminosilicate Half-Life Formation Time in the 2H Evaporator

    Energy Technology Data Exchange (ETDEWEB)

    Fondeur, F.F.


    The 2H Evaporator contains large quantities of aluminosilicate solids deposited on internal fixtures. The proposed cleaning operations will dissolve the solids in nitric acid. Operations will then neutralize the waste prior to transfer to a waste tank. Combining recent calculations of heat transfer for the 2H Evaporator cleaning operations and laboratory experiments for dissolution of solid samples from the pot, the authors estimated the re-formation rate for aluminosilicates during cooling. The results indicate a half-life formation of 17 hours when evaporator solution cools from 60 degrees C and 9 hours when cooled from 90 degrees C.

  19. Determination of half-life and photon emission probabilities of (65)Zn. (United States)

    Luca, Aurelian; Amiot, Marie-Noëlle; Morel, Jean


    A (65) Zn radioactive solution standardized by an absolute measurement method at Laboratoire National Henri Becquerel (LNHB), was sent to Bureau International des Poids et Mesures (BIPM), in order to include the results in their database. The activity value determined at BIPM was in good agreement with that stated by LNHB (the difference was 0.3%). Additional measurements of (65) Zn activity and half-life were also carried out, by using a 4pigamma ionization chamber; the half-life value proposed by this work: 244.15 (10) days, is consistent to others reported in the literature. The spectra analysis was performed by gamma-ray spectrometry with high-purity germanium detectors, with the aim to improve the accuracy of the photon emission probabilities values of this nuclide. The determined photon emission probabilities are 0.498 for the 1115 ke V gamma-ray, 0.347 and 0.0479 for the X-rays Cu-K(alpha) and Cu-K(beta); the associated uncertainties are 0.4%, 0.9% and 1.1%, respectively.

  20. Half-life Measurements of Excited Levels in Fission Products around Mass Number 150

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Y., E-mail: [Radioisotope Research Center, Nagoya University, Nagoya 464-8602 (Japan); Shima, Y. [Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan); Hayashi, H. [Institute of Health Biosciences, the University of Tokushima, Tokushima 770-8509 (Japan); Taniguchi, A. [Research Reactor Institute, Kyoto University, Kumatori 590-0494 (Japan); Shibata, M. [Radioisotope Research Center, Nagoya University, Nagoya 464-8602 (Japan)


    A spectrometer to measure nuclear level half-lives has been installed at the on-line isotope separator of the Kyoto University Reactor. This spectrometer consists of a LaBr3 scintillator, a thin plastic scintillator and an HPGe detector. Half-lives are deduced using the β-γ-γ delayed coincidence method. The prompt-time distribution curves measured with the spectrometer give a time resolution (FWHM) of 600 ps for 100-keV γ rays. This resolution means that half-lives down to the subnanosecond range or shorter can be measured. We reported recent measurements of the half-life of {sup 149}Pr and {sup 149}Nd. Some of the more interesting results include the first determination of the half-lives of {sup 149}Pr levels at 86.5 and 125.6 keV, which are 4.2(5) ns and 1.0(2) ns, respectively. In addition, the data indicate that the half-life of the 270.8-keV level in {sup 149}Nd is not 5.1(3) ns as reported previously, but 0.42(3) ns.

  1. High-Precision Half-life Measurements for the Superallowed β+ Emitter 14O

    Directory of Open Access Journals (Sweden)

    Laffoley A. T.


    Full Text Available The half-life of 14O, a superallowed Fermi β+ emitter, has been determined via simultaneous γ and β counting experiments at TRIUMF’s Isotope Separator and Accelerator facility. Following the implantation of 14O samples at the center of the 8π spectrometer, a γ counting measurement was performed by detecting the 2313 keV γ-rays emitted from the first excited state of the daughter 14N using 20 high-purity germanium (HPGe detectors. A simultaneous β counting experiment was performed using a fast plastic scintillator positioned directly behind the implantation site. The results, T½(γ = 70:632 ± 0:094 s and T½(β = 70:610 ± 0:030 s, are consistent with one another and, together with eight previous measurements, establish a new average for the 14O half-life of T½ = 70:619 ± 0:011 s with a reduced χ2 of 0.99.

  2. Study of the dependence of 198Au half-life on source geometry

    CERN Document Server

    Lindstrom, R M; Buncher, J B; Greene, G L; Jenkins, J H; Krause, D E; Mattes, J J; Yue, A; 10.1016/j.nima.2010.06.270


    We report the results of an experiment to determine whether the half-life of \\Au{198} depends on the shape of the source. This study was motivated by recent suggestions that nuclear decay rates may be affected by solar activity, perhaps arising from solar neutrinos. If this were the case then the $\\beta$-decay rates, or half-lives, of a thin foil sample and a spherical sample of gold of the same mass and activity could be different. We find for \\Au{198}, $(T_{1/2})_{\\rm foil}/(T_{1/2})_{\\rm sphere} = 0.999 \\pm 0.002$, where $T_{1/2}$ is the mean half-life. The maximum neutrino flux at the sample in our experiments was several times greater than the flux of solar neutrinos at the surface of the Earth. We show that this increase in flux leads to a significant improvement in the limits that can be inferred on a possible solar contribution to nuclear decays.

  3. Isolation of human anti-serum albumin Fab antibodies with an extended serum-half life. (United States)

    Kang, Hyeon-Ju; Kim, Hye-Jin; Cha, Sang-Hoon


    The serum albumin (SA) has been exploited to generate long-acting biotherapeutics by taking advantage of the FcRn-mediated recycling mechanism in a direct or an indirect way. Since Fab fragments have been proven to be clinically safe for human usage, we assumed that human anti-SA Fab antibodies could have a great potential as a carrier molecule to extend the serum half-life of therapeutic proteins. We, herein, had attempted to isolate anti-SA Fab antibodies from HuDVFab-8L antibody library via a phage display technology, and identified eight discrete human Fab antibodies. One of the Fab antibodies, SL335, showed the strongest binding reactivity to human SA with nM range of affinity at both pH 6 and pH 7.4, and cross-reacted to SAs from various species including rat, mouse, canine and monkey. The in vivo pharmacokinetic assay using a rat model indicated that SL335 has approximately 10 fold longer serum half-life and 26 to 44-fold increase in AUC0 → ∞ compared to the negative control Fab molecule in both intravenous and subcutaneous administrations. Knowing that Fabs have proven to be safe in clinics for a long time, SL335 seems to have a great potential in generating long-acting protein drugs by tagging effector molecules with either chemical conjugation or genetic fusion.

  4. Changing Paradigm of Hemophilia Management: Extended Half-Life Factor Concentrates and Gene Therapy. (United States)

    Kumar, Riten; Dunn, Amy; Carcao, Manuel


    Management of hemophilia has evolved significantly in the last century-from recognition of the causative mechanism in the 1950s to commercially available clotting factor concentrates in the 1960s. Availability of lyophilized concentrates in the 1970s set the stage for home-based therapy, followed by introduction of virally attenuated plasma-derived, and then recombinant factor concentrates in the 1980s and 1990s, respectively. The subsequent years saw a paradigm shift in treatment goals from on-demand therapy to prophylactic factor replacement starting at an early age, to prevent hemarthrosis becoming the standard of care for patients with severe hemophilia. In the developed world, the increasing use of home-based prophylactic regimens has significantly improved the quality of life, and life expectancy of patients with severe hemophilia. Seminal developments in the past 5 years, including the commercial availability of extended half-life factor concentrates and the publication of successful results of gene therapy for patients with hemophilia B, promise to further revolutionize hemophilia care over the next few decades. In this review, we summarize the evolution of management for hemophilia, with a focus on extended half-life factor concentrates and gene therapy.

  5. Protein HESylation for half-life extension: synthesis, characterization and pharmacokinetics of HESylated anakinra. (United States)

    Liebner, Robert; Mathaes, Roman; Meyer, Martin; Hey, Thomas; Winter, Gerhard; Besheer, Ahmed


    Half-life extension (HLE) is becoming an essential component of the industrial development of small-sized therapeutic peptides and proteins. HESylation(®) is a HLE technology based on coupling drug molecules to the biodegradable hydroxyethyl starch (HES). In this study, we report on the synthesis, characterization and pharmacokinetics of HESylated anakinra, where anakinra was conjugated to propionaldehyde-HES using reductive amination, leading to a monoHESylated protein. Characterization using size exclusion chromatography and dynamic light scattering confirmed conjugation and the increase in molecular size, while Fourier transform infrared spectroscopy showed that the secondary structure of the conjugate was not affected by coupling. Meanwhile, microcalorimetry and aggregation studies showed a significant increase in protein stability. Surface plasmon resonance and microscale thermophoresis showed that the conjugate retained its nanomolar affinity, and finally, the pharmacokinetics of the HESylated protein exhibited a 6.5-fold increase in the half-life, and a 45-fold increase in the AUC. These results indicate that HESylation(®) is a promising HLE technology.

  6. Half-life determination for {sup 108}Ag and {sup 110}Ag

    Energy Technology Data Exchange (ETDEWEB)

    Zahn, Guilherme S.; Genezini, Frederico A. [Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP, P.O. Box 11049, São Paulo, 05422-970 (Brazil)


    In this work, the half-life of the short-lived silver radionuclides {sup 108}Ag and {sup 110}Ag were measured by following the activity of samples after they were irradiated in the IEA-R1 reactor. The results were then fitted using a non-paralizable dead time correction to the regular exponential decay and the individual half-life values obtained were then analyzed using both the Normalized Residuals and the Rajeval techniques, in order to reach the most exact and precise final values. To check the validity of dead-time correction, a second correction method was also employed by means of counting a long-lived {sup 60}Co radioactive source together with the samples as a livetime chronometer. The final half-live values obtained using both dead-time correction methods were in good agreement, showing that the correction was properly assessed. The results obtained are partially compatible with the literature values, but with a lower uncertainty, and allow a discussion on the last ENSDF compilations' values.

  7. Accurate measurements of {sup 129}I concentration by isotope dilution using MC-ICPMS for half-life determination

    Energy Technology Data Exchange (ETDEWEB)

    Isnard, Helene; Nonell, Anthony; Marie, Mylene [Commissariat a l' Energie Atomique et aux Energies alternatives (CEA), Gif Sur Yvette (France). DEN, DPC, SEARS, LANIE; Chartier, Frederic [Commissariat a l' Energie Atomique et aux Energies alternatives (CEA), Gif Sur Yvette (France). DEN, DPC


    Determining the {sup 129}I concentration, a long-lived radionuclide present in spent nuclear fuel, is a major issue for nuclear waste disposal purpose. {sup 129}I also has to be measured in numerous environmental, nuclear and biological samples. To be able to accurately determine the {sup 129}I concentration, an analytical method based on the use of a multicollector-inductively coupled plasma mass spectrometer (MC-ICPMS) combined with an isotope dilution technique using an {sup 127}I spike, was developed. First, the influence of different media (HNO{sub 3}, NaOH and TMAH) on natural {sup 127}I signal intensity and stability and on memory effects was studied. Then an analytical procedure was developed by taking into account the correction of blanks and interferences. Tellurium was chosen for instrumental mass bias correction, as no certified standards with suitable {sup 127}I/{sup 129}I ratio are available. Finally, the results, reproducibility and uncertainties obtained for the {sup 129}I concentration determined by isotope dilution with a {sup 127}I spike are presented and discussed. The final expanded relative uncertainty obtained for the iodine-129 concentration was lower than 0.7% (k = 1). This precise {sup 129}I determination in association with further activity measurements of this nuclide on the same sample will render it possible to determine a new value of the {sup 129}I half-life with a reduced uncertainty (0.76%, k = 1).

  8. Degradation and half-life of DNA present in biomass from a genetically-modified organism during land application. (United States)

    Halter, Mathew C; Zahn, James A


    White biotechnology has made a positive impact on the chemical industry by providing safer, more efficient chemical manufacturing processes that have reduced the use of toxic chemicals, harsh reaction conditions, and expensive metal catalysts, which has improved alignment with the principles of Green Chemistry. The genetically-modified (GM) biocatalysts that are utilized in these processes are typically separated from high-value products and then recycled, or eliminated. Elimination routes include disposal in sanitary landfills, incineration, use as a fuel, animal feed, or reuse as an agricultural soil amendment or other value-added products. Elimination routes that have the potential to impact the food chain or environment have been more heavily scrutinized for the fate and persistence of biological products. In this study, we developed and optimized a method for monitoring the degradation of strain-specific DNA markers from a genetically-modified organism (GMO) used for the commercial production of 1,3-propanediol. Laboratory and field tests showed that a marker for heterologous DNA in the GM organism was no longer detectable by end-point polymerase chain reaction (PCR) after 14 days. The half-life of heterologous DNA was increased by 17% (from 42.4 to 49.7 h) after sterilization of the soil from a field plot, which indicated that abiotic factors were important in degradation of DNA under field conditions. There was no evidence for horizontal transfer of DNA target sequences from the GMO to viable organisms present in the soil.

  9. Half-life measurement of neutron-rich isotope 237Th

    Institute of Scientific and Technical Information of China (English)


    60 MeV/u 18O ions were used to bombard natural uranium targets, and the heavy neutron-rich isotope 237Th was produced via multi-nucleon transfer reaction and dissipative fragmentation of the heavy target. A relatively fast radiochcmical procedure was used to separate thorium from the mixture of uranium and complex reaction products. The chemically separated thorium fractions were studied by the γ-ray spectroscopic method. The behaviors of the growth and decay of 853.7 and 865.0 keV γ rays of 237pa decay were observed. Thc half-life of 237Th was determined to be 4.69±0.60 min.

  10. Precision measurement of the half-life of $^{109}$In in large and small lattice environments

    CERN Multimedia

    We propose to undertake high precision measurements of the half-life of $^{109}$In in large and small lattice environments to study the effect of compression on the electron capture nuclear decay rate. Such studies are of general interest having implications in many areas ranging from astrophysics to geophysics. At present, very little data is available on the change of electron capture decay rate under compression and the available data seems to indicate that the observed increase of the electron capture decay rate under compression is much greater than the predictions of the best available density functional calculations as obtained from TB-LMTO or WIEN2K codes. The proposed experiment should generate more data thus clarifying the experimental situation.

  11. Precise half-life values for two neutrino double beta decay

    CERN Document Server

    Barabash, A S


    All existing "positive" results on two neutrino double beta decay in different nuclei were analyzed. Using the procedure recommended by the Particle Data Group, weighted average values for half-lives of $^{48}$Ca, $^{76}$Ge, $^{82}$Se, $^{96}$Zr, $^{100}$Mo, $^{100}$Mo - $^{100}$Ru ($0^+_1$), $^{116}$Cd, $^{130}$Te, $^{150}$Nd, $^{150}$Nd - $^{150}$Sm($0^+_1$) and $^{238}$U were obtained. Existing geochemical data were analyzed and recommended values for half-lives of $^{128}$Te, $^{130}$Te and $^{130}$Ba are proposed. Given the measured half-life values, nuclear matrix elements were calculated. I recommend the use of these results as the most currently reliable values for the half-lives and nuclear matrix elements.

  12. Average and recommended half-life values for two neutrino double beta decay

    CERN Document Server

    Barabash, A S


    All existing positive results on two neutrino double beta decay in different nuclei were analyzed. Using the procedure recommended by the Particle Data Group, weighted average values for half-lives of $^{48}$Ca, $^{76}$Ge, $^{82}$Se, $^{96}$Zr, $^{100}$Mo, $^{100}$Mo - $^{100}$Ru ($0^+_1$), $^{116}$Cd, $^{130}$Te, $^{136}$Xe, $^{150}$Nd, $^{150}$Nd - $^{150}$Sm ($0^+_1$) and $^{238}$U were obtained. Existing geochemical data were analyzed and recommended values for half-lives of $^{128}$Te, and $^{130}$Ba are proposed. Given the measured half-life values, nuclear matrix elements were calculated using latest (more reliable and precise) values for phase space factor. Finally, previous results (PRC 81 (2010) 035501) were up-dated and results for $^{136}$Xe were added.

  13. Precise half-life measurements for $^{38}$Ca and $^{39}$Ca

    CERN Document Server

    Blank, B; Demonchy, C-E; Borge, M J G; Matea, I; Munoz, F; Huikari, J; Dominguez-Reyes, R; Plaisir, C; Sturm, S; Canchel, G; Delahaye, P; Audirac, L; Fraile, L M; Serani, L; Lunney, D; Pedroza, J-L; Bey, A; Souin, J; Hui, Tran Trong; Delalee, F; Tengblad, O; Wenander, F


    The half-lives of Ca-38 and Ca-39 have been measured at ISOLDE of CERN. The REXTRAP facility was used to prepare ultra-clean samples of radioactive nuclei for precision decay spectroscopy. Ca-38 is one of the T-z = -1, 0(+). 0(+) beta-emitting nuclides used to determine the vector coupling constant of the weak interaction and the V-ud quark-mixing matrix element. The result obtained, T-1/2 = 443.8(19) ms, is four times more precise than the average of previous measurements. For Ca-39, a half-life of T-1/2 = 860.7(10) ms is obtained, a result in agreement with the average value from the literature.

  14. Development of a time-variable nuclear pulser for half life measurements

    Energy Technology Data Exchange (ETDEWEB)

    Zahn, Guilherme S.; Domienikan, Claudio; Carvalhaes, Roberto P. M.; Genezini, Frederico A. [Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP. P.O. Box 11049, Sao Paulo, 05422-970 (Brazil)


    In this work a time-variable pulser system with an exponentially-decaying pulse frequency is presented, which was developed using the low-cost, open-source Arduino microcontroler plataform. In this system, the microcontroller produces a TTL signal in the selected rate and a pulse shaper board adjusts it to be entered in an amplifier as a conventional pulser signal; both the decay constant and the initial pulse rate can be adjusted using a user-friendly control software, and the pulse amplitude can be adjusted using a potentiometer in the pulse shaper board. The pulser was tested using several combinations of initial pulse rate and decay constant, and the results show that the system is stable and reliable, and is suitable to be used in half-life measurements.

  15. Alpha-decay half-life semiempirical relationships with self-improving parameters

    Energy Technology Data Exchange (ETDEWEB)

    Poenaru, D.N.; Ivascu, M.; Mazilu, D. (Institutul Central de Fizica, Bucharest (Romania))


    From the alpha decay Q-values, the partial half-life T is estimated by using five semiempirical relationships. The parameters of these formulae have been obtained from a fit with a given set of experimental data on four groups of alpha emitters: even-even, even-odd, odd-even and odd-odd. For each nuclide only the strongest transition is considered and the data are automatically sorted into the four groups mentioned above. There are three options: one can use either the present set of parameter values, a new one given as input data, or new values computed by using a better set of experimental data (more accurate or more complete). For each group of nuclides, up to 8 (or 9) families of curves could be plotted, optionally, with the line printer.

  16. Half-life of each dioxin and PCB congener in the human body

    Energy Technology Data Exchange (ETDEWEB)

    Ogura, Isamura [National Institute of Advanced Industrial Science and Technology, Tsukuba (Japan)


    It is well known that dioxin and PCB congeners accumulate in the human body. For assessing their toxicological risk, it is important to know the half-life of each congener in the human body. This study summarizes the overall half-lives of congeners in humans as reported in the literature, and compares them with the half-lives due to fecal and sebum excretions, as estimated by data on the concentrations of congeners in feces and sebum in the literature. In addition, the overall half-lives of congeners for the general Japanese population were estimated from the data on dietary intakes and concentrations in the human body reported by the municipalities.

  17. ORIGEN-S Decay Data Library and Half-Life Uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Hermann, O.W.


    The results of an extensive update of the decay data of the ORIGEN-S library are presented in this report. The updated decay data were provided for both the ORIGEN-S and ORIGEN2 libraries in the same project. A complete edit of the decay data plus the available half-life uncertainties are included in Appendix A. A detailed description of the types of data contained in the library, the format of the library, and the data sources are also presented. Approximately 24% of the library nuclides are stable, 66% were updated from ENDF/B-VI, about 8% were updated from ENSDF, and the remaining 2% were not updated. Appendix B presents a listing of percentage changes in decay heat from the old to the updated library for all nuclides containing a difference exceeding 1% in any parameter.

  18. Liposomal Formulation of Bevasizuamb for Intravitreal Administration: Increased Half-Life, Decreased Side Effects

    Directory of Open Access Journals (Sweden)

    Siamak Zarei Ghanavati


    Full Text Available Intravitreal injection is the common method for treatment of the posterior segment eye diseases. The advantage of intravitreal injection is achieving the desired concentration of drug inside the eye and reduction of drug side effects. Unfortunately, repeated intravitreal injections can cause several ocular complications including; vitreous hemorrhage, endophthalmitis, retinal detachment and cataract. For this reason, it seems the usage of sustained release drug delivery systems is helpful. Bevacizumab (Avastin®, antivascular endothelial growth factor (VEGF monoclonal antibody, is used for the treatment of different ocular diseases such as neovascular age-related macular degeneration, neovascular glaucoma, diabetic retinopathy, retinal vein occlusions, etc. For reduction of drug side effects and improvement of drug half-life after intravitreal administration, we suggest preparation of liposomal bevacizumab as novel drug delivery system and comparison of this new formulation with conventional formulation in the market.

  19. The antitumor agent 3-bromopyruvate has a short half-life at physiological conditions. (United States)

    Glick, Matthew; Biddle, Perry; Jantzi, Josh; Weaver, Samantha; Schirch, Doug


    Clinical research is currently exploring the validity of the anti-tumor candidate 3-bromopyruvate (3-BP) as a novel treatment for several types of cancer. However, recent publications have overlooked rarely-cited earlier work about the instability of 3-BP and its decay to 3-hydroxypyruvate (3-HP) which have obvious implications for its mechanism of action against tumors, how it is administered, and for precautions when preparing solutions of 3-BP. This study found the first-order decay rate of 3-BP at physiological temperature and pH has a half-life of only 77 min. Lower buffer pH decreases the decay rate, while choice of buffer and concentration do not affect it. A method for preparing more stable solutions is also reported.

  20. Q value and half-life of double-electron capture in Os-184

    CERN Document Server

    Smorra, C; Beyer, T; Blaum, K; Block, M; Düllmann, Ch E; Eberhardt, K; Eibach, M; Eliseev, S; Langanke, K; Martinez-Pinedo, G; Nagy, Sz; Nörtershäuser, W; Renisch, D; Shabaev, V M; Tupitsyn, I I; Zubova, N A


    Os-184 has been excluded as a promising candidate for the search of neutrinoless double-electron capture. High-precision mass measurements with the Penning-trap mass spectrometer TRIGA-TRAP resulted in a marginal resonant enhancement with = -8.89(58) keV excess energy to the 1322.152(22) keV 0+ excited state in W-184. State-of-the-art energy density functional calculations are applied for the evaluation of the nuclear matrix elements to the excited states predicting a strong suppression due to the large deformation of mother and daughter states. The half-life of the transition in Os-184 exceeds T_{1/2} > 1.3 10^{29} years for an effective neutrino mass of 1 eV.

  1. PASylation of Murine Leptin Leads to Extended Plasma Half-Life and Enhanced in Vivo Efficacy. (United States)

    Morath, Volker; Bolze, Florian; Schlapschy, Martin; Schneider, Sarah; Sedlmayer, Ferdinand; Seyfarth, Katrin; Klingenspor, Martin; Skerra, Arne


    Leptin plays a central role in the control of energy homeostasis and appetite and, thus, has attracted attention for therapeutic approaches in spite of its limited pharmacological activity owing to the very short circulation in the body. To improve drug delivery and prolong plasma half-life, we have fused murine leptin with Pro/Ala/Ser (PAS) polypeptides of up to 600 residues, which adopt random coil conformation with expanded hydrodynamic volume in solution and, consequently, retard kidney filtration in a similar manner as polyethylene glycol (PEG). Relative to unmodified leptin, size exclusion chromatography and dynamic light scattering revealed an approximately 21-fold increase in apparent size and a much larger molecular diameter of around 18 nm for PAS(600)-leptin. High receptor-binding activity for all PASylated leptin versions was confirmed in BIAcore measurements and cell-based dual-luciferase assays. Pharmacokinetic studies in mice revealed a much extended plasma half-life after ip injection, from 26 min for the unmodified leptin to 19.6 h for the PAS(600) fusion. In vivo activity was investigated after single ip injection of equimolar doses of each leptin version. Strongly increased and prolonged hypothalamic STAT3 phosphorylation was detected for PAS(600)-leptin. Also, a reduction in daily food intake by up to 60% as well as loss in body weight of >10% lasting for >5 days was observed, whereas unmodified leptin was merely effective for 1 day. Notably, application of a PASylated superactive mouse leptin antagonist (SMLA) led to the opposite effects. Thus, PASylated leptin not only provides a promising reagent to study its physiological role in vivo but also may offer a superior drug candidate for clinical therapy.

  2. Measurement of the 135Cs half-life with accelerator mass spectrometry and inductively coupled plasma mass spectrometry (United States)

    MacDonald, C. M.; Cornett, R. J.; Charles, C. R. J.; Zhao, X. L.; Kieser, W. E.


    The isotope 135Cs is quoted as having a half-life of 2.3 Myr. However, there are three published values ranging from 1.8 to 3 Myr. This research reviews previous measurements and reports a new measurement of the half-life using newly developed accelerator mass spectrometry (AMS) and inductively coupled plasma mass spectrometry (ICPMS) techniques along with β and γ radiometric analysis. The half-life was determined to be (1.6 ±0.6 ) ×106 yr by AMS and (1.3 ±0.2 ) ×106 yr by ICPMS with 95% confidence. The two values agree with each other but differ from the accepted value by ˜40 % .

  3. Towards a Measurement of the Half-Life of {sup 60}Fe for Stellar and Early Solar System Models

    Energy Technology Data Exchange (ETDEWEB)

    Ostdiek, K.; Anderson, T.; Bauder, W.; Bowers, M.; Collon, P.; Dressler, R.; Greene, J.; Kutschera, W.; Lu, W.; Paul, M.


    Radioisotopes, produced in stars and ejected into the Interstellar Medium, are important for constraining stellar and early Solar System (ESS) models. In particular, the half-life of the radioisotope, Fe-60, can have an impact on calculations for the timing for ESS events, the distance to nearby Supernovae, and the brightness of individual, non-steady-state Fe gamma ray sources in the Galaxy. A half-life measurement has been undertaken at the University of Notre Dame and measurements of the Fe-60/Fe-56 concentration of our samples using Accelerator Mass Spectrometry has begun. This result will be coupled with an activity measurement of the isomeric decay in Co-60, which is the decay product of Fe. Preliminary half-life estimates of (2.53 +/- 0.24) x 10(6) years seem to confirm the recent measurement by Rugel et al. (2009). (C) 2015 Elsevier B.V. All rights reserved.

  4. New evaluation of alpha decay half-life of {sup 190}Pt isotope for the Pt-Os dating system

    Energy Technology Data Exchange (ETDEWEB)

    Tavares, O.A.P.; Medeiros, E.L. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Terranova, M.L. [Universita degli Studi di Roma Tor Vergata (Italy). Dipt. di Scienze e Tecnologie Chimiche; Istituto Nazionale di Fisica Nucleare (INFN), Rome (Italy)


    A semiempirical model based on the quantum mechanical tunnelling mechanism of alpha emission from nuclei has been used to evaluate the half-life of the Pt isotopes. For the important naturally occurring {sup 190}Pt isotope, the radiogenic parent in the {sup 190} Pt {yields} {sup 186}Os dating system, the model yielded a half-life value of (3.7{+-} 0.3) versus 10{sup 11} y. This is comparable to (3.2{+-}0.1) versus 10{sup 11} y which was obtained in the last direct counting experiment to measure the alpha activity of {sup 190}Pt (Tavares and Terranova, Rad. Measurem. 27 (1997) 19). A literature survey of available alpha decay half-life values for {sup 190}Pt isotope is also reported. The significant discrepancies found between data obtained by direct counting, indirect geological methods and different calculation models are analysed and discussed. (author)

  5. A shorter 146Sm half-life measured and implications for 146Sm-142Nd chronology in the solar system. (United States)

    Kinoshita, N; Paul, M; Kashiv, Y; Collon, P; Deibel, C M; DiGiovine, B; Greene, J P; Henderson, D J; Jiang, C L; Marley, S T; Nakanishi, T; Pardo, R C; Rehm, K E; Robertson, D; Scott, R; Schmitt, C; Tang, X D; Vondrasek, R; Yokoyama, A


    The extinct p-process nuclide (146)Sm serves as an astrophysical and geochemical chronometer through measurements of isotopic anomalies of its α-decay daughter (142)Nd. Based on analyses of (146)Sm/(147)Sm α-activity and atom ratios, we determined the half-life of (146)Sm to be 68 ± 7 (1σ) million years, which is shorter than the currently used value of 103 ± 5 million years. This half-life value implies a higher initial (146)Sm abundance in the early solar system, ((146)Sm/(144)Sm)(0) = 0.0094 ± 0.0005 (2σ), than previously estimated. Terrestrial, lunar, and martian planetary silicate mantle differentiation events dated with (146)Sm-(142)Nd converge to a shorter time span and in general to earlier times, due to the combined effect of the new (146)Sm half-life and ((146)Sm/(144)Sm)(0) values.

  6. The half-life of Ascaris lumbricoides prevalence in Japanese school children. (United States)

    Kurosawa, Carmen Miwa; Ito, Takehiko; Takaki, Jiro; Wang, Bin-Ling; Wang, Da-Hong; Takigawa, Tomoko; Ogino, Keiki


    In the present study, we examined the dynamic of school-health-based parasite control and the related socio-economic influences. This is an ecological study based on data from 46 prefectures in Japan. The exponential decay of Ascaris lumbricoides prevalence was calculated by iterative least-squares method. Pearson's correlation and multiple linear regression model analysis were performed to assess the associations between the prevalence of Ascaris lumbricoides in Japanese school children and socio-economic variables such as the prefecture income per capita, the percentage of primary industry, the population density per 1 km2, the diffusion rate of population under water supply, and the percentage of upper secondary school enrollment. The results indicated that the parasite carrier rate was higher in younger students. The half-life of Ascaris lumbricoides prevalence was approximately 3 years with significant variation among prefectures. Multiple regression analyses showed that the decrease of infection in elementary and lower secondary school children had a significant positive association with primary industry and a significant negative association with prefecture income per capita. The school-health-based parasite intervention differs by prefecture and has changed over time according to the respective prefectural stage of economic development.

  7. Kinetic modeling and half life study on bioremediation of crude oil dispersed by Corexit 9500

    Energy Technology Data Exchange (ETDEWEB)

    Zahed, Mohammad Ali [School of Civil Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Penang (Malaysia); Aziz, Hamidi Abdul, E-mail: [School of Civil Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Penang (Malaysia); Isa, Mohamed Hasnain [Civil Engineering Department, Universiti Teknologi PETRONAS, 31750 Tronoh, Perak (Malaysia); Mohajeri, Leila; Mohajeri, Soraya [School of Civil Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Penang (Malaysia); Kutty, Shamsul Rahman Mohamed [Civil Engineering Department, Universiti Teknologi PETRONAS, 31750 Tronoh, Perak (Malaysia)


    Hydrocarbon pollution in marine ecosystems occurs mainly by accidental oil spills, deliberate discharge of ballast waters from oil tankers and bilge waste discharges; causing site pollution and serious adverse effects on aquatic environments as well as human health. A large number of petroleum hydrocarbons are biodegradable, thus bioremediation has become an important method for the restoration of oil polluted areas. In this research, a series of natural attenuation, crude oil (CO) and dispersed crude oil (DCO) bioremediation experiments of artificially crude oil contaminated seawater was carried out. Bacterial consortiums were identified as Acinetobacter, Alcaligenes, Bacillus, Pseudomonas and Vibrio. First order kinetics described the biodegradation of crude oil. Under abiotic conditions, oil removal was 19.9% while a maximum of 31.8% total petroleum hydrocarbons (TPH) removal was obtained in natural attenuation experiment. All DCO bioreactors demonstrated higher and faster removal than CO bioreactors. Half life times were 28, 32, 38 and 58 days for DCO and 31, 40, 50 and 75 days for CO with oil concentrations of 100, 500, 1000 and 2000 mg/L, respectively. The effectiveness of Corexit 9500 dispersant was monitored in the 45 day study; the results indicated that it improved the crude oil biodegradation rate.

  8. Measurement of the Double Beta Decay Half-life of 130Te with the NEMO-3 Detector

    CERN Document Server

    Arnold, R; Baker, J; Barabash, A S; Basharina-Freshville, A; Blondel, S; Bongrand, M; Broudin-Bay, G; Brudanin, V; Caffrey, A J; Chapon, A; Chauveau, E; Durand, D; Egorov, V; Flack, R; Garrido, X; Grozier, J; Guillon, B; Hubert, Ph; Jackson, C M; Jullian, S; Kauer, M; Klimenko, A; Kochetov, O; Konovalov, S I; Kovalenko, V; Lalanne, D; Lamhamdi, T; Lang, K; Liptak, Z; Lutter, G; Mamedov, F; Marquet, Ch; Martin-Albo, J; Mauger, F; Mott, J; Nachab, A; Nemchenok, I; Nguyen, C H; Nova, F; Novella, P; Ohsumi, H; Pahlka, R B; Perrot, F; Piquemal, F; Reyss, J L; Richards, B; Ricol, J S; Saakyan, R; Sarazin, X; Shitov, Yu; Simard, L; Šimkovic, F; Smolnikov, A; Söldner-Rembold, S; Štekl, I; Suhonen, J; Sutton, C S; Szklarz, G; Thomas, J; Timkin, V; Torre, S; Tretyak, V I; Umatov, V; Vála, L; Vanyushin, I; Vasiliev, V; Vorobel, V; Vylov, T; Zukauskas, A


    This Letter reports results from the NEMO-3 experiment based on an exposure of 1275 days with 661g of 130Te in the form of enriched and natural tellurium foils. With this data set the double beta decay rate of 130Te is found to be non-zero with a significance of 7.7 standard deviations and the half-life is measured to be T1/2 = (7.0 +/- 0.9(stat) +/- 1.1(syst)) x 10^{20} yr. This represents the most precise measurement of this half-life yet published and the first real-time observation of this decay.

  9. β-decay half-life of the rp-process waiting-point nuclide Mo84 (United States)

    Stoker, J. B.; Mantica, P. F.; Bazin, D.; Becerril, A.; Berryman, J. S.; Crawford, H. L.; Estrade, A.; Guess, C. J.; Hitt, G. W.; Lorusso, G.; Matos, M.; Minamisono, K.; Montes, F.; Pereira, J.; Perdikakis, G.; Schatz, H.; Smith, K.; Zegers, R. G. T.


    A half-life of 2.2 ± 0.2 s has been deduced for the ground-state β decay of Mo84, more than 1σ shorter than the previously adopted value. Mo84 is an even-even N=Z nucleus lying on the proton dripline, created during explosive hydrogen burning in type I x-ray bursts in the rapid proton capture (rp) process. The effect of the measured half-life on rp-process reaction flow is explored. Implications on theoretical treatments of nuclear deformation in Mo84 are also discussed.

  10. High-precision half-life and branching-ratio measurements for superallowed Fermi β+ emitters at TRIUMF – ISAC

    Directory of Open Access Journals (Sweden)

    Laffoley A. T.


    Full Text Available A program of high-precision half-life and branching-ratio measurements for superallowed Fermi β emitters is being carried out at TRIUMF’s Isotope Separator and Accelerator (ISAC radioactive ion beam facility. Recent half-life measurements for the superallowed decays of 14O, 18Ne, and 26Alm, as well as branching-ratio measurements for 26Alm and 74Rb are reported. These results provide demanding tests of the Standard Model and the theoretical isospin symmetry breaking (ISB corrections in superallowed Fermi β decays.

  11. PEGylation extends circulation half-life while preserving in vitro and in vivo activity of tissue inhibitor of metalloproteinases-1 (TIMP-1.

    Directory of Open Access Journals (Sweden)

    Jyotica Batra

    Full Text Available Excess proteolytic activity of matrix metalloproteinases (MMPs contributes to the development of arthritis, cardiovascular diseases and cancer progression, implicating these enzymes as therapeutic targets. While many small molecule inhibitors of MMPs have been developed, clinical uses have been limited, in part by toxicity and off-target effects. Development of the endogenous tissue inhibitors of metalloproteinases (TIMPs as recombinant biopharmaceuticals represents an alternative therapeutic approach; however, the short plasma half-life of recombinant TIMPs has restricted their potential in this arena. To overcome this limitation, we have modified recombinant human TIMP-1 (rhTIMP-1 by PEGylation on lysine residues. We analyzed a mixture of mono- and di-PEGylated rhTIMP-1 species modified by attachment of 20 kDa mPEG chains (PEG(20K-TIMP-1, as confirmed by SELDI-TOF mass spectrometry. This preparation retained complete inhibitory activity toward the MMP-3 catalytic domain and partial inhibitory activity toward full length MMP-9. Pharmacokinetic evaluation showed that PEGylation extended the plasma half-life of rhTIMP-1 in mice from 1.1 h to 28 h. In biological assays, PEG(20K-TIMP-1 inhibited both MMP-dependent cancer cell invasion and tumor cell associated gelatinase activity. Overall these results suggest that PEGylated TIMP-1 exhibits improved potential for development as an anti-cancer recombinant protein therapeutic, and additionally may offer potential for clinical applications in the treatment of other diseases.

  12. Precise measurement of the 222Rn half-life: A probe to monitor the stability of radioactivity

    Directory of Open Access Journals (Sweden)

    E. Bellotti


    Full Text Available We give the results of a study on the 222Rn decay we performed in the Gran Sasso Laboratory (LNGS by detecting the gamma rays from the radon progeny. The motivation was to monitor the stability of radioactivity measuring several times per year the half-life of a short lifetime (days source instead of measuring over a long period the activity of a long lifetime (tens or hundreds of years source. In particular, we give a possible reason of the large periodical fluctuations in the count rate of the gamma rays due to radon inside a closed canister which has been described in literature and which has been attributed to a possible influence of a component in the solar irradiation affecting the nuclear decay rates. We then provide the result of four half-life measurements we performed underground at LNGS in the period from May 2014 to January 2015 with radon diffused into olive oil. Briefly, we did not measure any change of the 222Rn half-life with a 8⋅10−5 precision. Finally, we provide the most precise value for the 222Rn half-life: 3.82146(16stat(4syst days.

  13. Brief report : enzyme inducers reduce elimination half-life after a single dose of nevirapine in healthy women

    NARCIS (Netherlands)

    L'homme, R.F.A.; Dijkema, T.; Ven, A.J.A.M. van der; Burger, D.M.


    OBJECTIVE: Single-dose nevirapine (SD-NVP) to prevent mother-to-child transmission (MTCT) of HIV is associated with development of NVP resistance, probably because of its long half-life in combination with a low genetic barrier to resistance. The objective of this study was to find enzyme inducers t

  14. Screening and ranking of POPs for global half-life: QSAR approaches for prioritization based on molecular structure. (United States)

    Gramatica, Paola; Papa, Ester


    Persistence in the environment is an important criterion in prioritizing hazardous chemicals and in identifying new persistent organic pollutants (POPs). Degradation half-life in various compartments is among the more commonly used criteria for studying environmental persistence, but the limited availability of experimental data or reliable estimates is a serious problem. Available half-life data for degradation in air, water, sediment, and soil, for a set of 250 organic POP-type chemicals, were combined in a multivariate approach by principal component analysis to obtain a ranking of the studied organic pollutants according to their relative overall half-life. A global half-life index (GHLI) applicable for POP screening purposes is proposed. The reliability of this index was verified in comparison with multimedia model results. This global index was then modeled as a cumulative end-point using a QSAR approach based on few theoretical molecular descriptors, and a simple and robust regression model externally validated for its predictive ability was derived. The application of this model could allow a fast preliminary identification and prioritization of not yet known POPs, just from the knowledge of their molecular structure. This model can be applied a priori also in the chemical design of safer and alternative non-POP compounds.

  15. Extending the Serum Half-Life of G-CSF via Fusion with the Domain III of Human Serum Albumin

    Directory of Open Access Journals (Sweden)

    Shuqiang Zhao


    Full Text Available Protein fusion technology is one of the most commonly used methods to extend the half-life of therapeutic proteins. In this study, in order to prolong the half-life of Granulocyte colony stimulating factor (G-CSF, the domain III of human serum albumin (3DHSA was genetically fused to the N-terminal of G-CSF. The 3DHSA-G-CSF fusion gene was cloned into pPICZαA along with the open reading frame of the α-factor signal under the control of the AOX1 promoter. The recombinant expression vector was transformed into Pichia pastoris GS115, and the recombinant strains were screened by SDS-PAGE. As expected, the 3DHSA-G-CSF showed high binding affinity with HSA antibody and G-CSF antibody, and the natural N-terminal of 3DHSA was detected by N-terminal sequencing. The bioactivity and pharmacokinetic studies of 3DHSA-G-CSF were respectively determined using neutropenia model mice and human G-CSF ELISA kit. The results demonstrated that 3DHSA-G-CSF has the ability to increase the peripheral white blood cell (WBC counts of neutropenia model mice, and the half-life of 3DHSA-G-CSF is longer than that of native G-CSF. In conclusion, 3DHSA can be used to extend the half-life of G-CSF.

  16. A Fab-Selective Immunoglobulin-Binding Domain from Streptococcal Protein G with Improved Half-Life Extension Properties.

    Directory of Open Access Journals (Sweden)

    Felix Unverdorben

    Full Text Available Half-life extension strategies have gained increasing interest to improve the pharmacokinetic and pharmacodynamic properties of protein therapeutics. Recently, we established an immunoglobulin-binding domain (IgBD from streptococcal protein G (SpGC3 as module for half-life extension. SpGC3 is capable of binding to the Fc region as well as the CH1 domain of Fab arms under neutral and acidic conditions.Using site-directed mutagenesis, we generated a Fab-selective mutant (SpGC3Fab to avoid possible interference with the FcRn-mediated recycling process and improved its affinity for mouse and human IgG by site-directed mutagenesis and phage display selections. In mice, this affinity-improved mutant (SpGC3FabRR conferred prolonged plasma half-lives compared with SpGC3Fab when fused to small recombinant antibody fragments, such as single-chain Fv (scFv and bispecific single-chain diabody (scDb. Hence, the SpGC3FabRR domain seems to be a suitable fusion partner for the half-life extension of small recombinant therapeutics.The half-life extension properties of SpGC3 can be retained by restricting binding to the Fab fragment of serum immunoglobulins and can be improved by increasing binding activity. The modified SpGC3 module should be suitable to extend the half-life of therapeutic proteins and, thus to improve therapeutic activity.


    Energy Technology Data Exchange (ETDEWEB)

    Jannik, T.; Paller, M.; Baker, R.


    During the operational history of the Savannah River Site (SRS), many different radionuclides have been released from site facilities into the SRS environment. However, only a relatively small number of pathways, most importantly {sup 137}Cs in fish and deer, have contributed significantly to doses and risks to the public. The “effective” half-lives (T{sub e}) of {sup 137}Cs (which include both physical decay and environmental dispersion) in Savannah River floodplain soil and vegetation and in fish and white-tailed deer from the SRS were estimated using long-term monitoring data. For 1974–2011, the T{sub e}s of {sup 137}Cs in Savannah River floodplain soil and vegetation were 17.0 years (95% CI = 14.2–19.9) and 13.4 years (95% CI = 10.8–16.0), respectively. These T{sub e}s were greater than in a previous study that used data collected only through 2005 as a likely result of changes in the flood regime of the Savannah River. Field analyses of {sup 137}Cs concentrations in deer collected during yearly controlled hunts at the SRS indicated an overall T{sub e} of 15.9 years (95% CI = 12.3–19.6) for 1965–2011; however, the T{sub e} for 1990–2011 was significantly shorter (11.8 years, 95% CI = 4.8–18.8) due to an increase in the rate of {sup 137}Cs removal. The shortest T{sub e}s were for fish in SRS streams and the Savannah River (3.5–9.0 years), where dilution and dispersal resulted in rapid {sup 137}Cs removal. Long-term data show that T{sub e}s are significantly shorter than the physical half-life of {sup 137}Cs in the SRS environment but that they can change over time. Therefore, it is desirable have a long period of record for calculating Tes and risky to extrapolate T{sub e}s beyond this period unless the processes governing {sup 137}Cs removal are clearly understood.

  18. Role of ligand-dependent GR phosphorylation and half-life in determination of ligand-specific transcriptional activity. (United States)

    Avenant, Chanel; Ronacher, Katharina; Stubsrud, Elisabeth; Louw, Ann; Hapgood, Janet P


    A central question in glucocorticoid mechanism of action via the glucocorticoid receptor (GR) is what determines ligand-selective transcriptional responses. Using a panel of 12 GR ligands, we show that the extent of GR phosphorylation at S226 and S211, GR half-life and transcriptional response, occur in a ligand-selective manner. While GR phosphorylation at S226 was shown to inhibit maximal transcription efficacy, phosphorylation at S211 is required for maximal transactivation, but not for transrepression efficacy. Both ligand-selective GR phosphorylation and half-life correlated with efficacy for transactivation and transrepression. For both expressed and endogenous GR, in two different cell lines, agonists resulted in the greatest extent of phosphorylation and the greatest extent of GR downregulation, suggesting a link between these functions. However, using phosphorylation-deficient GR mutants we established that phosphorylation of the GR at S226 or S211 does not determine the rank order of ligand-selective GR transactivation. These results are consistent with a model whereby ligand-selective GR phosphorylation and half-life are a consequence of upstream events, such as ligand-specific GR conformations, which are maintained in the phosphorylation mutants.

  19. Activity measurement of 60Fe through the decay of 60mCo and confirmation of its half-life

    CERN Document Server

    Ostdiek, Karen; Bauder, William; Bowers, Matthew; Clark, Adam; Collon, Philippe; Dressler, Rugard; Greene, John; Kutschera, Walter; Lu, Wenting; Nelson, Austin; Paul, Michael; Robertson, Daniel; Schumann, Dorothea; Skulski, Michael


    The half-life of the neutron-rich nuclide, $^{60}\\text{Fe}$ has been in dispute in recent years. A measurement in 2009 published a value of $(2.62 \\pm 0.04)\\times10^{6}$ years, almost twice that of the previously accepted value from 1984 of $(1.49 \\pm 0.27)\\times10^{6}$ years. This longer half-life was confirmed in 2015 by a new measurement, resulting in a value of $(2.50 \\pm 0.12)\\times10^{6}$ years. All three half-life measurements used the grow-in of the $\\gamma$-ray lines in $^{60}\\text{Ni}$ from the decay of the ground state of $^{60\\text{g}}\\text{Co}$ (t$_{1/2}$=5.27 years) to determine the activity of a sample with a known number of $^{60}\\text{Fe}$ atoms. In contrast, the work presented here measured the $^{60}\\text{Fe}$ activity directly with the 58.6 keV $\\gamma$-ray line from the short-lived isomeric state of $^{60\\text{m}}\\text{Co}$ (t$_{1/2}$=10.5 minutes), thus being independent of any possible contamination from long-lived $^{60\\text{g}}\\text{Co}$. A fraction of the material from the 2015 exper...

  20. Precise measurement of the 222Rn half-life: a probe to monitor the stability of radioactivity

    CERN Document Server

    Bellotti, E; Di Carlo, G; Laubenstein, M; Menegazzo, R


    We give the results of a study on the 222Rn decay we performed in the Gran Sasso Laboratory (LNGS) by detecting the gamma rays from the radon progeny. The motivation was to monitor the stability of radioactivity measuring several times per year the half-life of a short lifetime (days) source instead of measuring over a long period the activity of a long lifetime (tens or hundreds of years) source. In particular, we give the reason of the large periodical fluctuations in the count rate of the gamma rays due to radon inside a closed canister which has been described in literature and which has been attributed to a possible influence of a component in the solar irradiation affecting the nuclear decay rates. We then provide the result of four half-life measurements we performed underground at LNGS in the period from May 2014 to January 2015 with radon diffused into olive oil. Briefly, we did not measure any change of the 222Rn half-life with a 8*10^-5 precision. Finally, we provide the most precise value for the ...

  1. Innovative methodology for intercomparison of radionuclide calibrators using short half-life in situ prepared radioactive sources

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, P. A. [Centro de Investigação do Instituto Português de Oncologia do Porto Francisco Gentil, EPE, Porto, Portugal and Departamento de Física e Astronomia, Faculdade de Ciências da Universidade do Porto (Portugal); Santos, J. A. M., E-mail: [Centro de Investigação do Instituto Português de Oncologia do Porto Francisco Gentil, EPE, Porto (Portugal); Serviço de Física Médica do Instituto Português de Oncologia do Porto Francisco Gentil, EPE, Porto (Portugal); Serviço de Medicina Nuclear do Instituto Português de Oncologia do Porto Francisco Gentil, EPE, Porto (Portugal); Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto (Portugal)


    Purpose: An original radionuclide calibrator method for activity determination is presented. The method could be used for intercomparison surveys for short half-life radioactive sources used in Nuclear Medicine, such as{sup 99m}Tc or most positron emission tomography radiopharmaceuticals. Methods: By evaluation of the resulting net optical density (netOD) using a standardized scanning method of irradiated Gafchromic XRQA2 film, a comparison of the netOD measurement with a previously determined calibration curve can be made and the difference between the tested radionuclide calibrator and a radionuclide calibrator used as reference device can be calculated. To estimate the total expected measurement uncertainties, a careful analysis of the methodology, for the case of{sup 99m}Tc, was performed: reproducibility determination, scanning conditions, and possible fadeout effects. Since every factor of the activity measurement procedure can influence the final result, the method also evaluates correct syringe positioning inside the radionuclide calibrator. Results: As an alternative to using a calibrated source sent to the surveyed site, which requires a relatively long half-life of the nuclide, or sending a portable calibrated radionuclide calibrator, the proposed method uses a source preparedin situ. An indirect activity determination is achieved by the irradiation of a radiochromic film using {sup 99m}Tc under strictly controlled conditions, and cumulated activity calculation from the initial activity and total irradiation time. The irradiated Gafchromic film and the irradiator, without the source, can then be sent to a National Metrology Institute for evaluation of the results. Conclusions: The methodology described in this paper showed to have a good potential for accurate (3%) radionuclide calibrators intercomparison studies for{sup 99m}Tc between Nuclear Medicine centers without source transfer and can easily be adapted to other short half-life radionuclides.

  2. Determination of the 10Be half-life by multicollector ICP-MS and liquid scintillation counting (United States)

    Chmeleff, Jérôme; von Blanckenburg, Friedhelm; Kossert, Karsten; Jakob, Dieter


    A new method was designed and used for determining the half-life of the isotope 10Be. The method is based on (1) accurate 10Be/ 9Be measurements of 9Be-spiked solutions of a 10Be-rich master solution using multicollector ICP mass spectrometry (MC-ICP-MS) and (2) liquid scintillation counting (LSC) using the CIEMAT/NIST method for determining the activity concentrations of the solutions whose 10Be concentrations were determined by mass spectrometry. Important requirements for the success of this approach (a) was the previous coating of glass ampoules filled for counting experiments with 9Be, thereby reducing the risk of the adsorptive loss of 10Be; (b) the removal of Boron from solutions to be measured by MC-ICP-MS by cation chromatography without the introduction of mass fractionation and (c) the accurate determination of the mass bias of 10Be/ 9Be measurements by ICP-MS which are always affected by the space-charge effect. The mass bias factor was determined to be 1.1862 ± 0.071 for 10Be/ 9Be from careful fitting and error propagation of ratios of measured Li, B, Si, Cr, Fe, Cu, Sr, Nd, Hf, Tl and U standard solutions of known composition under the same measurement conditions. Employing this factor, an absolute 10Be/ 9Be ratio of 1.464 ± 0.014 was determined for a first dilution of the 10Be-rich master solution. This solution is now available as an absolute Be ratio standard in AMS measurements. Finally, a half-life of (1.386 ± 0.016) My (standard uncertainty) was calculated. This value is much more precise than previous estimates and was derived from a fully independent set of experiments. In a parallel, fully independent study using the same master solution, Korschinek et al. [35] have determined a half-life of (1.388 ± 0.018) My. The combined half-life and uncertainty amounts to (1.387 ± 0.012) My. We suggest the use of this value in nuclear studies and in studies that make use of cosmogenic 10Be in environmental and geologic samples.

  3. Shorter 146Sm half-life and revised 146Sm-142Nd ages of planetary mantle differentiation

    CERN Document Server

    Kinoshita, N; Kashiv, Y; Collon, P; Deibel, C M; DiGiovine, B; Greene, J P; Henderson, D J; Jiang, C L; Marley, S T; Nakanishi, T; Pardo, R C; Rehm, K E; Robertson, D; Scott, R; Schmitt, C; Tang, X D; Vondrasek, R; Yokoyama, A


    The extinct short-lived nuclide 146Sm, synthesized in stellar events by the p-process, serves as both an astrophysical and geochemical chronometer through measurements of isotopic anomalies of its alpha-decay daughter 142Nd. Evidence of live 146Sm, quantitatively established for the early Solar System, constrains the time between p-process nucleosynthesis and condensation of the first solid materials. Samarium-146 is used also to date silicate mantle differentiation events in a number of planetary bodies, including Earth. We performed a new measurement of the 146Sm half-life and our result, t = 68\\pm7 (1sigma) million year (Ma), is significantly shorter than the value currently used for 146Sm-142Nd chronology (103\\pm5 Ma). We show here that the shorter 146Sm half-life value implies a higher initial Solar System ratio, (146Sm/144Sm)_0 = 0.0094\\pm0.0005 (2sigma), than the recently derived value 0.0085\\pm0.0007, or that used in most studies 0.008\\pm0.001. Planetary differentiation processes dated by 146Sm-142Nd ...

  4. Direct Deposition Effect on the Distribution of Radiocesium in Persimmon Trees and the Effective Half-life

    Energy Technology Data Exchange (ETDEWEB)

    Tagami, Keiko; Uchida, Shigeo [National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-7444 (Japan)


    Radiocesium ({sup 137}Cs) concentrations in persimmon tree tissues collected at Chiba, about 220 km south from Fukushima Daiichi nuclear power plant (FDNPP), were measured to obtain half-life of radiocesium in the trees. Persimmon (Diospyros kaki) is a deciduous tree and bears edible fruits in autumn. There were no leaves when the sampling area was received the radioactive fallout in March 2011 due to the FDNPP accident; the amount of {sup 137}Cs radioactivity in this area was ca. 13 kBq/m{sup 3} Both {sup 137}Cs and {sup 134}Cs were found in the newly emerged shoots of the persimmon trees collected at 26 April 2011 mainly due to foliar uptake. The concentrations were 1.1 kBq/kg-dry for {sup 137}Cs and 1.3 kBq/kg-dry for {sup 134}Cs. After that, continuous sampling of leaves, branches and fruits of the persimmon trees had been carried out for two years. Immediately after the collection, samples were transferred to our laboratory and weighed to obtain fresh weight. Leaf samples were usually separated into two portions; one portion was washed with tap water to remove dust from the surface and the other portion was not treated. For fruit samples, if it is possible, fruit flesh, peal and non-edible part were separated. All the samples were oven-dried at 80 deg. C for three days at least. Each dried sample was chopped into fine pieces, mixed well, and then transferred into plastic vessels separately. Radioactivity concentration was measured by a Ge-detecting system (Seiko EG and G Ortec) using 3000-40000 s counting intervals. By August 14, 2013, about 140 samples were collected from the trees; about 60 samples were leaves (both washed and untreated). Radiocesium concentrations in tree leaves decreased with time, and the effective half-life was about 190 d; the value was similar to those in branches (160 d for new branches, and 250 d for 1-2 y.o. branches) and fruits (250 d for fruit flesh and 230 d for peals). Thus we concluded that the half-life of radiocesium in

  5. An Advance in Prescription Opioid Vaccines: Overdose Mortality Reduction and Extraordinary Alteration of Drug Half-Life. (United States)

    Kimishima, Atsushi; Wenthur, Cody J; Zhou, Bin; Janda, Kim D


    Prescription opioids (POs) such as oxycodone and hydrocodone are highly effective medications for pain management, yet they also present a substantial risk for abuse and addiction. The consumption of POs has been escalating worldwide, resulting in tens of thousands of deaths due to overdose each year. Pharmacokinetic strategies based upon vaccination present an attractive avenue to suppress PO abuse. Herein, the preparation of two active PO vaccines is described that were found to elicit high-affinity antiopioid antibodies through a structurally congruent drug-hapten design. Administration of these vaccines resulted in a significant blockade of opioid analgesic activity, along with an unprecedented increase in drug serum half-life and protection against lethal overdose.

  6. 209Tl half-life and gamma-ray measurements of radionuclides belonging to the (4 n + 1) decay chain (United States)

    Ardisson, G.; Barci, V.; El Samad, O.


    Gamma-ray spectra of radiochemically separated 221Fr, 213Bi and 209Tl sources were measured using coaxial and planar HPGe detectors. The energies and emission probabilities of eight new gamma-ray transitions were observed in the decay of 209Tl; a half-life of (2.161±0.007) min was measured. Twenty-two gamma-rays have been attributed to the β-decay of 213Bi, of which 17 are new with respect to previous studies. The 213Po level scheme was determined using γ-γ coincidence measurements: eight excited states are proposed of which six are new. Preliminary measurements of the α-decay of 221Fr revealed the existence of 18 gamma-ray transitions of which eight are reported for the first time.

  7. The functional half-life of an mRNA depends on the ribosome spacing in an early coding region

    DEFF Research Database (Denmark)

    Pedersen, Margit; Nissen, Søren; Mitarai, Namiko;


    . Here, we characterize a determinant of the functional stability of an mRNA, which is located in the early coding region. Using literature values for the mRNA half-lives of variant lacZ mRNAs in Escherichia coli, we modeled how the ribosome spacing is affected by the translation rate of the individual...... of slowly translated codons before codon 20 or after codon 45 should shorten or prolong, respectively, the functional mRNA half-life by altering the ribosome density in the important region. These predictions were tested on eight new lacZ variants, and their experimentally determined mRNA half-lives all...


    Directory of Open Access Journals (Sweden)

    Samuel Enahoro Agarry


    Full Text Available In this study, comparative potential effects of commercial activated carbon (CAC and plantain peel-derived biochar (PPBC of different particle sizes and dosage to stimulate petroleum hydrocarbon biodegradation in soil were investigated. Microcosms containing soil were spiked with weathered Bonny light crude oil (WBLCO (10% w/w and amended with different particle sizes (0.02, 0.07 and 0.48 mm and dosage (20, 30 and 40 g of CAC and PPBC, respectively. The bioremediation experiments were carried out for a period of 28 days under laboratory conditions. The results showed that there was a positive relationship between the rate of petroleum hydrocarbons reduction and presence of the CAC and PPBC in crude oil contaminated soil microcosms. The WBLCO biodegradation data fitted well to the first-order kinetic model. The model revealed that WBLCO contaminated-soil microcosms amended with CAC and PPBC had higher biodegradation rate constants (k as well as lower half-life times (t1/2 than unamended soil (natural attenuation remediation system. The rate constants increased while half-life times decreased with decreased particle size and increased dosage of amendment agents. ANOVA statistical analysis revealed that WBLCO biodegradation in soil was significantly (p = 0.05 influenced by the addition of CAC and biochar amendment agents, respectively. However, Tukey’s post hoc test (at p = 0.05 showed that there was no significant difference in the bioremediation efficiency of CAC and PPBC. Thus, amendment of soils with biochar has the potential to be an inexpensive, efficient, environmentally friendly and relatively novel strategy to mitigate organic compound-contaminated soil.

  9. Label-free Fab and Fc affinity/avidity profiling of the antibody complex half-life for polyclonal and monoclonal efficacy screening. (United States)

    Read, Thomas; Olkhov, Rouslan V; Williamson, E Diane; Shaw, Andrew M


    A unified approach to affinity screening for Fab and Fc interactions of an antibody for its antigen and FcγR receptor has been developed. An antigen array is used for the Fab affinity and cross-reactivity screening and protein A/G proxy is the FcγR receptor. The affinities are derived using a simple 1:1 binding model with a consistent error analysis. The association and dissociation kinetics are measured over optimised times for accurate determination. The Fab/Fc affinities are derived for ten antibodies: mAb-actin (mouse), pAb-BSA (sheep), pAb-collagen V (rabbit), pAb-CRP (goat), mAb-F1 (mouse), mAbs (mouse) 7.3, 12.3, 29.3, 36.3 and 46.3 raised against LcrV in Yersinia pestis. The rate of the dissociation of antigen-antibody complexes relates directly to their immunological function as does the Fc-FcγR complex and a new half-life plot has been defined with a Fab/Fc half-life range of 17-470 min. The upper half-life value points to surface avidity. Two antibodies that are protective as an immunotherapy define a Fab half-life >250 min and an Fc half-life >50 min as characteristics of ideal interactions which can form the basis of an antibody screen for immunotherapy.

  10. Comparison of serum immunoglobulin G half-life in dairy calves fed colostrum, colostrum replacer or administered with intravenous bovine plasma. (United States)

    Murphy, Jacob M; Hagey, Jill V; Chigerwe, Munashe


    In calves, passive immunity of immunoglobulins can be acquired through ingestion of colostrum or colostrum replacers. Plasma can been used to supplement immunoglobulins in healthy or sick calves. Serum half-life of colostral derived immuglobulin G (IgG) is estimated to be 20 days. Half-life of IgG is important in determining response to antigens and timing of vaccination in calves. To date studies evaluating half-life of colostrum replacer or plasma derived IgG are lacking. The objectives of this study were to compare the serum half-life of IgG derived from colostrum, colostrum replacer and plasma in dairy calves reared up to 35 days of age. Thirty Jersey calves were randomly assigned to receive colostrum or colostrum replacer by oroesophageal tubing or plasma by intravenous administration. Serum samples were collected at 2, 5, 7, 10, 14, 21, 28 and 35 days. Serum IgG concentrations were determined by radial immunodiffusion. The results indicated that half-life for IgG in colostrum fed (28.5 days) or plasma transfused calves (27.3 days) was longer than colostrum replacer fed calves (19.1 days). Further studies are required to evaluate pathogen specific immunoglobulins in order to recommend vaccination timing in calves fed colostrum replacers.

  11. Measurement of the two neutrino double beta decay half-life of Zr-96 and search for associated neutrinoless processes with the NEMO-3 detector

    CERN Document Server

    Argyriades, J; Augier, C; Baker, J; Barabash, A S; Bongrand, M; Broudin-Bay, G; Brudanin, V B; Caffrey, A J; Chapon, A; Chauveau, E; Daraktchieva, Z; Durand, D; Egorov, V G; Fatemi-Ghomi, N; Flack, R; Freshville, A; Guillon, B; Hubert, Ph; Jullian, S; Kauer, M; King, S; Kochetov, O I; Konovalov, S I; Kovalenko, V E; Lalanne, D; Lang, K; Lemiere, Y; Lutter, G; Mamedov, F; Marquet, Ch; Martín-Albo, J; Mauger, F; Nachab, A; Nasteva, I; Nemchenok, I B; Nova, F; Novella, P; Ohsumi, H; Pahlka, R B; Perrot, F; Piquemal, F; Reyss, J L; Ricol, J S; Saakyan, R; Sarazin, X; Simard, L; Shitov, Yu A; Smolnikov, A A; Snow, S; Söldner-Rembold, S; Stekl, I; Sutton, C S; Szklarz, G; Thomas, J; Timkin, V V; Tretyak, V I; Tretyak, Vl I; Umatov, V I; Vàla, L; Vanyushin, I A; Vasiliev, V A; Vorobel, V; Vylov, Ts


    Using 1221 days of data from the NEMO-3 detector, the measurement of Zr-96 2vbb decay half-life is [2.35 +/- 0.14(stat) +/- 0.19(syst)] x 10^19 yr. Different characteristics of the final state electrons have been studied, such as the energy sum, individual electron energy, and angular distribution. The 2v nuclear matrix element is extracted using the measured 2vbb half-life and is 0.049 +/- 0.003. A 90% CL limit is set on the 0vbb decay half-life of > 9.2 x 10^21 yr corresponding to a limit on the effective Majorana neutrino mass < 7.2 - 19.5 eV. Limits on other mechanisms of 0vbb decay have also been set.

  12. Perfluorooctane Sulfonate Plasma Half-Life Determination and Long-Term Tissue Distribution in Beef Cattle (Bos taurus). (United States)

    Lupton, Sara J; Dearfield, Kerry L; Johnston, John J; Wagner, Sarah; Huwe, Janice K


    Perfluorooctane sulfonate (PFOS) is used in consumer products as a surfactant and is found in industrial and consumer waste, which ends up in wastewater treatment plants (WWTPs). PFOS does not breakdown during WWTP processes and accumulates in the biosolids. Common practices include application of biosolids to pastures and croplands used for feed, and as a result, animals such as beef cattle are exposed to PFOS. To determine plasma and tissue depletion kinetics in cattle, 2 steers and 4 heifers were dosed with PFOS at 0.098 mg/kg body weight and 9.1 mg/kg, respectively. Plasma depletion half-lives for steers and heifers were 120 ± 4.1 and 106 ± 23.1 days, respectively. Specific tissue depletion half-lives ranged from 36 to 385 days for intraperitoneal fat, back fat, muscle, liver, bone, and kidney. These data indicate that PFOS in beef cattle has a sufficiently long depletion half-life to permit accumulation in edible tissues.

  13. Plasma half-life and organ uptake ratio of radiolabeled glandular kallikrein in control and nephrectomized rats

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, K.; Iwata, T.; Kokubu, T.


    The purified rat urinary kallikrein was radiolabeled by lactoperoxidase method and by chloramine T method. Plasma half-life of radiolabeled kallikrein was 5.06 +/- 0.59 (n = 5) min in control rats and 5.24 +/- 0.42 (n = 5) min in nephrectomized rats. There was no difference between two groups. From autoradiogram, main metabolic organs of radiolabeled kallikrein were liver, kidney and spleen. Total uptake of radiolabeled kallikrein in ech organ was the highest in liver (73.2%). The uptake per g tissue of radiolabeled kallikrein in each organ was high in liver (33.0%), kidney (31.4%) and spleen (21.1%). These results suggest that the active kallikrein is metabolized mainly in the liver, and kidney is not so an important organ to metabolize or to eliminate the active kallikrein in plasma. In order to clarify the mode of existence of active kallikrein in plasma, the following experiment was done by using disc gel electrophoresis. Radioactive profile of radiolabeled kallikrein showed one peak (Rf = 1.0), but radiolabeled kallikrein mixed with rat plasma showed two peaks, that is small peak (Rf = 1.0), and main peak (RF = 0.5). The most of radiolabeled kallikrein was bound to plasma protein and only five per cent was in free form. Furthermore, the binding of radiolabeled kallikrein to plasma protein was interfered by the addition of active kallikrein. These results suggest the possibility of existence of kallikrein binding protein in plasma.

  14. Use of short half-life cosmogenic isotopes to quantify sediment mixing and transport in karst conduits (United States)

    Paylor, R.


    Particulate inorganic carbon (PIC) transport and flux in karst aquifers is poorly understood. Methods to quantify PIC flux are needed in order to account for total inorganic carbon removal (chemical plus mechanical) from karst settings. Quantifying PIC flux will allow more accurate calculations of landscape denudation and global carbon sink processes. The study concentrates on the critical processes of the suspended sediment component of mass flux - surface soil/stored sediment mixing, transport rates and distance, and sediment storage times. The primary objective of the study is to describe transport and mixing with the resolution of single storm-flow events. To quantify the transport processes, short half-life cosmogenic isotopes are utilized. The isotopes 7Be (t1/2 = 53d) and 210Pb (t1/2 = 22y) are the primary isotopes measured, and other potential isotopes such as 137Cs and 241Am are investigated. The study location is at Mammoth Cave National Park within the Logsdon River watershed. The Logsdon River conduit is continuously traversable underground for two kilometers. Background levels and input concentrations of isotopes are determined from soil samples taken at random locations in the catchment area, and suspended sediment collected from the primary sinking stream during a storm event. Suspended sediment was also collected from the downstream end of the conduit during the storm event. After the storm flow receded, fine sediment samples were taken from the cave stream at regular intervals to determine transport distances and mixing ratios along the conduit. Samples were analyzed with a Canberra Industries gamma ray spectrometer, counted for 24 hours to increase detection of low radionuclide activities. The measured activity levels of radionuclides in the samples were adjusted for decay from time of sampling using standard decay curves. The results of the study show that surface sediment mixing, transport and storage in karst conduits is a dynamic but

  15. Half-life and rational drug use of paclitaxel%紫杉醇的半衰期与合理用药

    Institute of Scientific and Technical Information of China (English)



    In this article,the author mainly discusses the relationship of paclitaxel drug metabolism in human body and its half-life to promote its rational drug use.Refer to the relevant medical literature at home and abroad in recent years,we have induction and summary.The relationship of paclitaxel half-life and pesticide effect is analyzed.The paclitaxel half-life can determine the metabolism degree of the drug in the body,so drug half-life plays a critical role in the process of rational drug use.%本文主要对紫杉醇药物在人体内的代谢与其半衰期的关系进行探讨,以促进其合理用药。笔者参阅近几年来国内外的相关医学文献,进行归纳、总结,分析紫杉醇半衰期与药效之间的关系。根据紫杉醇的半衰期可以判定药物在人体内的代谢程度,因此药物半衰期在合理用药的过程中发挥着至关重要的作用。

  16. Database for mRNA Half-Life of 19 977 Genes Obtained by DNA Microarray Analysis of Pluripotent and Differentiating Mouse Embryonic Stem Cells (United States)

    Sharova, Lioudmila V.; Sharov, Alexei A.; Nedorezov, Timur; Piao, Yulan; Shaik, Nabeebi; Ko, Minoru S.H.


    Degradation of mRNA is one of the key processes that control the steady-state level of gene expression. However, the rate of mRNA decay for the majority of genes is not known. We successfully obtained the rate of mRNA decay for 19 977 non-redundant genes by microarray analysis of RNA samples obtained from mouse embryonic stem (ES) cells. Median estimated half-life was 7.1 h and only <100 genes, including Prdm1, Myc, Gadd45 g, Foxa2, Hes5 and Trib1, showed half-life less than 1 h. In general, mRNA species with short half-life were enriched among genes with regulatory functions (transcription factors), whereas mRNA species with long half-life were enriched among genes related to metabolism and structure (extracellular matrix, cytoskeleton). The stability of mRNAs correlated more significantly with the structural features of genes than the function of genes: mRNA stability showed the most significant positive correlation with the number of exon junctions per open reading frame length, and negative correlation with the presence of PUF-binding motifs and AU-rich elements in 3′-untranslated region (UTR) and CpG di-nucleotides in the 5′-UTR. The mRNA decay rates presented in this report are the largest data set for mammals and the first for ES cells. PMID:19001483

  17. Database for mRNA half-life of 19 977 genes obtained by DNA microarray analysis of pluripotent and differentiating mouse embryonic stem cells. (United States)

    Sharova, Lioudmila V; Sharov, Alexei A; Nedorezov, Timur; Piao, Yulan; Shaik, Nabeebi; Ko, Minoru S H


    Degradation of mRNA is one of the key processes that control the steady-state level of gene expression. However, the rate of mRNA decay for the majority of genes is not known. We successfully obtained the rate of mRNA decay for 19 977 non-redundant genes by microarray analysis of RNA samples obtained from mouse embryonic stem (ES) cells. Median estimated half-life was 7.1 h and only genes, including Prdm1, Myc, Gadd45 g, Foxa2, Hes5 and Trib1, showed half-life less than 1 h. In general, mRNA species with short half-life were enriched among genes with regulatory functions (transcription factors), whereas mRNA species with long half-life were enriched among genes related to metabolism and structure (extracellular matrix, cytoskeleton). The stability of mRNAs correlated more significantly with the structural features of genes than the function of genes: mRNA stability showed the most significant positive correlation with the number of exon junctions per open reading frame length, and negative correlation with the presence of PUF-binding motifs and AU-rich elements in 3'-untranslated region (UTR) and CpG di-nucleotides in the 5'-UTR. The mRNA decay rates presented in this report are the largest data set for mammals and the first for ES cells.

  18. Platelet half-life in patients with primary hyperlipoproteinemia type IIa, IIb, and IV according to Fredrickson with and without clinical signs of atherosclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, E.; Sinzinger, H.; Widhalm, K.; Kaliman, J.; Hoefer, R. (Vienna Univ. (Austria). 2. Medizinische Klinik; Ludwig Boltzmann-Institut fuer Nuklearmedizin, Vienna (Austria); Vienna Univ. (Austria). Kinderklinik; Vienna Univ. (Austria). Kardiologische Klinik)


    It is generally accepted that platelet half-life is shortened in atherosclerotic vascular diseases. Concerning changes due to hyperlipoproteinemia (HLP), however, there exist only few data. Therefore, we examined the platelet-half life in 60 patients with recently discovered HLP type IIa, IIb and IV according to Fredrickson before treatment in comparison to 60 controls. 33 of the HLP-patients had no clinical symptoms of angiopathy. 27 patients suffered from peripheral vascular disease or from coronary heart disease as verified by angiography. The labelling of autologous platelets was performed with of /sup 111/Indium-oxine-sulfate at 37/sup 0/C for 5 minutes. The mean labelling efficiency was 90%, the recovery after 2 hours about 70%. Serum lipoproteins were estimated by means of ultracentrifugation and polyanionprecipitation according to Lipid Research Clinic Methods. In the patients with HLP platelet half-life was significantly shortened in comparison to the control group (p < 0.01). These changes were most pronounced in patients with HLP-type IIa and with atherosclerotic lesions, respectively. In patients with HLP-type IIa a very close correlation could be demonstrated between platelet half-life and LDL-cholesterol (r = -0.72; p < 0.001) as well as total cholesterol (r = -0.73; p < 0.001). These data prove that in HLP in-vivo platelet function as measured by platelet survival is significantly influenced even before the occurrence of clinically relevant symptoms of atherosclerosis.

  19. Fast renal trapping of porcine Luteinizing Hormone (pLH shown by 123I-scintigraphic imaging in rats explains its short circulatory half-life

    Directory of Open Access Journals (Sweden)

    Locatelli Alain


    Full Text Available Abstract Background Sugar moieties of gonadotropins play no primary role in receptor binding but they strongly affect their circulatory half-life and consequently their in vivo biopotencies. In order to relate more precisely hepatic trapping of these glycoproteic hormones with their circulatory half-life, we undertook a comparative study of the distribution and elimination of porcine LH (pLH and equine CG (eCG which exhibit respectively a short and a long half-life. This was done first by following half-lives of pLH in piglets with hepatic portal circulation shunted or not. It was expected that such a shunt would enhance the short half-life of pLH. Subsequently, scintigraphic imaging of both 123I-pLH and 123I-eCG was performed in intact rats to compare their routes and rates of distribution and elimination. Methods Native pLH or eCG was injected to normal piglets and pLH was tested in liver-shunted anæsthetized piglet. Blood samples were recovered sequentially over one hour time and the hormone concentrations were determined by a specific ELISA method. Scintigraphic imaging of 123I-pLH and 123I-eCG was performed in rats using a OPTI-CGR gamma camera. Results In liver-shunted piglets, the half-life of pLH was found to be as short as in intact piglets (5 min. In the rat, the half-life of pLH was also found to be very short (3–6 min and 123I-pLH was found to accumulate in high quantity in less than 10 min post injection at the level of kidneys but not in the liver. 123I-eCG didn't accumulate in any organ in the rats during the first hour, plasma concentrations of this gonadotropin being still elevated (80% at this time. Conclusion In both the porcine and rat species, the liver is not responsible for the rapid elimination of pLH from the circulation compared to eCG. Our scintigraphic experiments suggest that the very short circulatory half-life of LH is due to rapid renal trapping.

  20. 基于下载量的期刊半衰期实证研究%Empirical Research on Half-life Period of Journals Based on Downloads

    Institute of Scientific and Technical Information of China (English)



    针对期刊网络老化速度研究较为薄弱的状况,以CNKI为数据源,通过对图书馆学情报学期刊下载量半衰期的实证分析研究,解读了下载量半衰期的特点,剖析了其与其它期刊评价指标的区别与联系。结果显示:期刊下载量半衰期明显小于被引半衰期和引用半衰期,与被引半衰期之间存在显著的相关性;与期刊其它计量指标相比有其特质与独立性;开展期刊下载量半衰期研究,有利于突破老化研究中引文分析的藩篱,提升期刊评价的时效性,拓展考察范围及促进期刊出版机构主动缩短网络版与印刷版之间的出版时滞,对期刊整体影响力的提升将产生积极影响。%Aimed at the unsubstantial research on aging speed of network periodicals and taking CNKI as data source, the paper interprets the characteristics of half-life period of downloads, and analyses its differences and relations with other periodical evaluation indexes through the empirical analysis research on half-life period of downloads as to library &information science periodicals. The result shows that half-life period of journal downloads are much smaller than cited half-life period and citation half-life period, and there is significant correlation with the cited half-life period among them as well;but compared with other periodical evaluation indexes, there exist its own traits and independence; it avails for the research of half-life periodical downloads to break through barriers in the study of aging citation analysis, to improve the timeliness of periodical evaluation and expand the scope of inspection, and also to promote periodical publishing organizations to take the initiative shortening of the delay between online and print publication, which will have a positive impact on the promotion of overall journal influence.

  1. A new value for the half-life of {sup 10}Be by Heavy-Ion Elastic Recoil Detection and liquid scintillation counting

    Energy Technology Data Exchange (ETDEWEB)

    Korschinek, G., E-mail: Gunther.Korschinek@ph.tum.d [Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany); Bergmaier, A. [Universitaet der Bundeswehr Muenchen, Fakultaet fuer Luft- und Raumfahrttechnik, Institut fuer Angewandte Physik und Messtechnik LRT2, Werner-Heisenberg-Weg 39, D-85577 Neubiberg (Germany); Faestermann, T. [Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany); Gerstmann, U.C. [Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, Institute of Radiation Protection, Ingolstaedter Landstr. 1, D-85764 Neuherberg (Germany); Knie, K.; Rugel, G. [Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany); Wallner, A. [VERA Laboratory, Faculty of Physics, University of Vienna, Waehringer Strasse 17, A-1090 Wien (Austria); Dillmann, I. [Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany); Dollinger, G. [Universitaet der Bundeswehr Muenchen, Fakultaet fuer Luft- und Raumfahrttechnik, Institut fuer Angewandte Physik und Messtechnik LRT2, Werner-Heisenberg-Weg 39, D-85577 Neubiberg (Germany); Lierse von Gostomski, Ch. [Lehrstuhl fuer Radiochemie, Technische Universitaet Muenchen, D-85748 Garching (Germany); Kossert, K. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany); Maiti, M.; Poutivtsev, M. [Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany); Remmert, A. [Lehrstuhl fuer Radiochemie, Technische Universitaet Muenchen, D-85748 Garching (Germany)


    The importance of {sup 10}Be in different applications of accelerator mass spectrometry (AMS) is well-known. In this context the half-life of {sup 10}Be has a crucial impact, and an accurate and precise determination of the half-life is a prerequisite for many of the applications of {sup 10}Be in cosmic-ray and earth science research. Recently, the value of the {sup 10}Be half-life has been the centre of much debate. In order to overcome uncertainties inherent in previous determinations, we introduced a new method of high accuracy and precision. An aliquot of our highly enriched {sup 10}Be master solution was serially diluted with increasing well-known masses of {sup 9}Be. We then determined the initial {sup 10}Be concentration by least square fit to the series of measurements of the resultant {sup 10}Be/{sup 9}Be ratio. In order to minimize uncertainties because of mass bias which plague other low-energy mass spectrometric methods, we used for the first time Heavy-Ion Elastic Recoil Detection (HI-ERD) for the determination of the {sup 10}Be/{sup 9}Be isotopic ratios, a technique which does not suffer from difficult to control mass fractionation. The specific activity of the master solution was measured by means of accurate liquid scintillation counting (LSC). The resultant combination of the {sup 10}Be concentration and activity yields a {sup 10}Be half-life of T{sub 1/2} = 1.388 +- 0.018 (1 s, 1.30%) Ma. In a parallel but independent study (Chmeleff et al. ), found a value of 1.386 +- 0.016 (1.15%) Ma. Our recommended weighted mean and mean standard error for the new value for {sup 10}Be half-life based on these two independent measurements is 1.387 +- 0.012 (0.87%) Ma.

  2. Refinements on the age-dependent half-life model for estimating child body burdens of polychlorodibenzodioxins and dibenzofurans. (United States)

    Kerger, Brent D; Leung, Hon-Wing; Scott, Paul K; Paustenbach, Dennis J


    We modified our prior age-dependent half-life model to characterize the range of child (ages 0-7) body burdens associated with dietary and environmental exposure to polychlorodibenzodioxins and furans (PCDD/Fs). Several exposure scenarios were evaluated. Infants were assumed to be either breast-fed or formula-fed from birth to 6 months of age. They then received intakes of PCDD/Fs through age 7 from foods based on weighted means estimates [JECFA, 2001. Joint FAO/WHO Committee on Food Additives. Fifty-seventh meeting, Rome, June 5-14 , 2001, pp. 24-40], and with or without exposures (ingestion and dermal) to urban residential soils at 1ppb TCDD toxic equivalents (TEQ). A one-compartment (adipose volume) toxicokinetic model for TCDD described by Kreuzer [Kreuzer, P.F., Csanady, Gy.A., et al., 1997. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and congeners in infants. A toxicokinetic model of human lifetime body burden by TCDD with special emphasis on its uptake by nutrition. Arch. Toxicol. 71, 383-400] was expanded to include the key non-TCDD congeners in human breast milk and adipose tissues, and two model parameter refinements were examined: (1) use of updated and more detailed age-correlated body fat mass data [CDC, 2000. Centers for Disease Control. CDC Growth Charts: United States. Advance Data from Vital and Health Statistics of the Centers for Disease Control and Prevention, National Center for Health Statistics, Number 314, December 2000]; (2) use of breast milk PCDD/F concentration data from sampling completed in 2000-2003 [Wittsiepe, J., Fürst, P., et al., 2004. PCDD/F and dioxin-like PCB in human blood and milk from German mothers. Organohalogen Compd. 66, 2865-2872]. The updated body fat mass data nearly halved the predicted peak body burden for breast-feeding and lowered the time-weighted average (TWA) body burdens from ages 0-7 by 30-40% for breast-fed and formula-fed infants. Combined use of the updated breast milk PCDD/F concentration and body fat

  3. Measurement of the half-life of the two-neutrino double beta decay of Ge-76 with the Gerda experiment

    CERN Document Server

    Agostini, M; Andreotti, E; Bakalyarov, A M; Balata, M; Barabanov, I; Heider, M Barnabe; Barros, N; Baudis, L; Bauer, C; Becerici-Schmidt, N; Bellotti, E; Belogurov, S; Belyaev, S T; Benato, G; Bettini, A; Bezrukov, L; Bode, T; Brudanin, V; Brugnera, R; Budjas, D; Caldwell, A; Cattadori, C; Chernogorov, A; Cossavella, F; Demidova, E V; Denisov, A; Domula, A; Egorov, V; Falkenstein, R; Ferella, A D; Freund, K; Froborg, F; Frodyma, N; Gangapshev, A; Garfagnini, A; Gazzana, S; Grambayr, P; Gurentsov, V; Gusev, K; Guthikonda, K K; Hampel, W; Hegai, A; Heisel, M; Hemmer, S; Heusser, G; Hofmann, W; Hult, M; Inzhechik, L V; Ioannucci, L; Csathy, J Janicsko; Jochum, J; Junker, M; Kianovsky, S; Kirpichnikov, I V; Kirsch, A; Klimenko, A; Knoepfle, K T; Kochetov, O; Kornoukhov, V N; Kusminov, V; Laubenstein, M; Lazzaro, A; Lebedev, V I; Lehnert, B; Liao, H Y; Lindner, M; Lippi, I; Liu, X; Lubashevskiy, A; Lubsandorzhiev, B; Lutter, G; Machado, A A; Majorovits, B; Maneschg, W; Nemchenok, I; Nisi, S; O'Shaughnessy, C; Pandola, L; Pelczar, K; Peraro, L; Pullia, A; Riboldi, S; Ritter, F; Sada, C; Salathe, M; Schmitt, C; Schoenert, S; Schreiner, J; Schulz, O; Schwingenheuer, B; Shevchik, E; Shirchenko, M; Simgen, H; Smolnikov, A; Stanco, L; Strecker, H; Tarka, M; Ur, C A; Vasenko, A A; Volynets, O; von Sturm, K; Walter, M; Wegmann, A; Wojcik, M; Yanovich, E; Zavarise, P; Zhitnikov, I; Zhukov, S V; Zinatulina, D; Zuber, K; Zuzel, G


    The primary goal of the GERmanium Detector Array (Gerda) experiment at the Laboratori Nazionali del Gran Sasso of INFN is the search for the neutrinoless double beta decay of Ge-76. High-purity germanium detectors made from material enriched in Ge-76 are operated directly immersed in liquid argon, allowing for a substantial reduction of the background with respect to predecessor experiments. The first 5.04 kg yr of data collected in Phase I of the experiment have been analyzed to measure the half-life of the neutrino-accompanied double beta decay of Ge-76. The observed spectrum in the energy range between 600 and 1800 keV is dominated by the double beta decay of Ge-76. The half-life extracted from Gerda data is T(1/2) = (1.84 +0.14 -0.10) 10^{21} yr.

  4. Nicotinic stimulation modulates tyrosine hydroxylase mRNA half-life and protein binding to the 3'UTR in a manner that requires transcription. (United States)

    Roe, David F; Craviso, Gale L; Waymire, Jack C


    Tyrosine hydroxylase (TH) expression increases in adrenal chromaffin cells treated with the nicotinic agonist, dimethylphenylpiperazinium (DMPP; 1 microM). We are using this response as a model of the changes in TH level that occur during increased cholinergic neural activity. Here we report a 4-fold increase in TH mRNA half-life in DMPP-treated cells chromaffin cells that is apparent when using a pulse-chase analysis to measure TH mRNA half-life. No increase is apparent using actinomycin D to measure half-life, indicating a requirement for ongoing transcription. Characterization of protein binding to the TH 3'UTR responsible for stabilization using labeled TH 3'UTR probes and electro-mobility shift assays shows the presence of two complexes both of which are increased by DMPP-treatment. The faster migrating complex (FMC) increases 2.5-fold and the slower migrating complex (SMC) increases 1.5-fold. Both changes are prevented by actinomycin D. Characterization of the protein binding to the TH UTR probes indicates SMC is disrupted by polyribonucleotides, poly (A) and poly (U), while binding to FMC is reduced by poly (CU). Separation of UV crosslinked RNA-protein complexes on SDS polyacrylamide gels shows FMC to contain a single protein whereas SMC contains three proteins. Northwesterns yielded similar results. Comparison of DMPP-induced protein binding with the poly C binding protein (PCBP) involved in hypoxia induced rat PC12 TH mRNA stability indicates none of the bovine UTR binding proteins are the PCBP. Thus, nicotinic stimulation produces a transcription-dependent increase in TH mRNA half-life that is mediated by previously unrecognized TH mRNA binding proteins.

  5. Pile-up corrections for high-precision superallowed {beta} decay half-life measurements via {gamma}-ray photopeak counting

    Energy Technology Data Exchange (ETDEWEB)

    Grinyer, G.F. [Department of Physics, University of Guelph, Guelph, Ont, N1G 2W1 (Canada)], E-mail:; Svensson, C.E.; Andreoiu, C. [Department of Physics, University of Guelph, Guelph, Ont, N1G 2W1 (Canada); Andreyev, A.N. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Austin, R.A.E. [Department of Astronomy and Physics, St. Mary' s University, Halifax, NS, B3H 3C3 (Canada); Ball, G.C. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Bandyopadhyay, D. [Department of Physics, University of Guelph, Guelph, Ont, N1G 2W1 (Canada); Chakrawarthy, R.S. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Finlay, P. [Department of Physics, University of Guelph, Guelph, Ont, N1G 2W1 (Canada); Garrett, P.E. [Department of Physics, University of Guelph, Guelph, Ont, Canada N1G 2W1 (Canada); TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Hackman, G. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Hyland, B. [Department of Physics, University of Guelph, Guelph, Ont, N1G 2W1 (Canada); Kulp, W.D. [School of Physics, Georgia Institute of Technology, Atlanta, GA 30332 0430 (United States); Leach, K.G. [Department of Physics, University of Guelph, Guelph, Ont, N1G 2W1 (Canada); Leslie, J.R. [Department of Physics, Queen' s University, Kingston, Ont., K7L 3N6 (Canada); Morton, A.C.; Pearson, C.J. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Phillips, A.A. [Department of Physics, University of Guelph, Guelph, Ont, N1G 2W1 (Canada); Sarazin, F. [Department of Physics, Colorado School of Mines, Golden, CO 80401 (United States); Schumaker, M.A. [Department of Physics, University of Guelph, Guelph, Ont, N1G 2W1 (Canada)] (and others)


    A general technique that corrects {gamma}-ray gated {beta} decay-curve data for detector pulse pile-up is presented. The method includes corrections for non-zero time-resolution and energy-threshold effects in addition to a special treatment of saturating events due to cosmic rays. This technique is verified through a Monte Carlo simulation and experimental data using radioactive beams of {sup 26}Na implanted at the center of the 8{pi}{gamma}-ray spectrometer at the ISAC facility at TRIUMF in Vancouver, Canada. The {beta}-decay half-life of {sup 26}Na obtained from counting 1809-keV {gamma}-ray photopeaks emitted by the daughter {sup 26}Mg was determined to be T{sub 1/2}=1.07167{+-}0.00055s following a 27{sigma} correction for detector pulse pile-up. This result is in excellent agreement with the result of a previous measurement that employed direct {beta} counting and demonstrates the feasibility of high-precision {beta}-decay half-life measurements through the use of high-purity germanium {gamma}-ray detectors. The technique presented here, while motivated by superallowed-Fermi {beta} decay studies, is general and can be used for all half-life determinations (e.g. {alpha}-, {beta}-, X-ray, fission) in which a {gamma}-ray photopeak is used to select the decays of a particular isotope.

  6. Clinical utility and patient perspectives on the use of extended half-life rFIXFc in the management of hemophilia B

    Directory of Open Access Journals (Sweden)

    Miguelino MG


    Full Text Available Maricel G Miguelino, Jerry S Powell Division of Hematology and Oncology, University of California Davis Medical Center, Sacramento, CA, USA Abstract: Hemophilia B is an X-linked genetic disease caused by mutation of the gene for coagulation protein factor IX (FIX, with an incidence of approximately once every 30,000 male births in all populations and ethnic groups. When severe, the disease leads to spontaneous life threatening bleeding episodes. When untreated, most patients die from bleeding complications before 25 years of age. Current therapy requires frequent intravenous infusions of therapeutic recombinant or plasma-derived protein concentrates containing FIX. Most patients administer the infusions at home every few days, and must limit their physical activities to avoid abnormal bleeding when the FIX activity levels are below normal. After completing the pivotal Phase III clinical trial, a new therapeutic FIX preparation that has been engineered for an extended half-life in circulation, received regulatory approval in March 2014 in Canada and the US. This new FIX represents a major therapeutic advance for patients with hemophilia B. The half-life is prolonged due to fusion of the native FIX molecule with the normal constant region of immunoglobulin G. This fusion molecule then follows the normal immunoglobulin recirculation pathways through endothelial cells, resulting in prolonged times in circulation. In the clinical trials, over 150 patients successfully used eftrenonacog alfa regularly for more than 1 year to prevent spontaneous bleeding, to successfully treat any bleeding episodes, and to provide effective coagulation for major surgery. All infusions were well tolerated and effective, with no inhibitors detected and no safety concerns. This promising therapy should allow patients to use fewer infusions to maintain appropriate FIX activity levels in all clinical settings. Keywords: factor IX, hemophilia B, prophylaxis, genetic

  7. New limits on Beyond Standard Model physics from a measurement of the half-life of the T=1/2 mirror decay of 19Ne

    CERN Document Server

    Broussard, L; Boswell, M S; Crowell, A S; Dendooven, P; Howell, C R; Kidd, M F; Jungmann, K; Kruithof, W L; Onderwater, C J G; Pattie, R W; Shidling, P D; Sohani, M; van der Hoek, D J; Rogachevskiy, A; Traykov, E; Versolato, O O; Willmann, L; Wilschut, H W; Young, A R


    The 1/2+ -> 1/2+ superallowed mixed mirror decay of 19Ne to 19F is excellently suited for high-precision studies of the weak interaction. However, there is some disagreement on the value of the half-life. In a new measurement we have determined this quantity to be T_{1/2} = 17.2832 +/- 0.0051_{(stat)} +/- 0.0066_{(sys)} seconds, which differs from the previous world average by 3 standard deviations. The impact of this measurement on limits for physics beyond the standard model such as the presence of tensor currents is discussed.

  8. Measurement of the Double-Beta Decay Half-Life and Search for the Neutrinoless Double-Beta Decay of $^{48}{\\rm Ca}$ with the NEMO-3 Detector

    CERN Document Server

    :,; Augier, C; Bakalyarov, A M; Baker, J D; Barabash, A S; Basharina-Freshville, A; Blondel, S; Blot, S; Bongrand, M; Brudanin, V; Busto, J; Caffrey, A J; Calvez, S; Cascella, M; Cerna, C; Cesar, J P; Chapon, A; Chauveau, E; Chopra, A; Duchesneau, D; Durand, D; Egorov, V; Eurin, G; Evans, J J; Fajt, L; Filosofov, D; Flack, R; Garrido, X; Gómez, H; Guillon, B; Guzowski, P; Hodák, R; Huber, A; Hubert, P; Hugon, C; Jullian, S; Klimenko, A; Kochetov, O; Konovalov, S I; Kovalenko, V; Lalanne, D; Lang, K; Lebedev, V I; Lemière, Y; Noblet, T Le; Liptak, Z; Liu, X R; Loaiza, P; Lutter, G; Mamedov, F; Marquet, C; Mauger, F; Morgan, B; Mott, J; Nemchenok, I; Nomachi, M; Nova, F; Nowacki, F; Ohsumi, H; Pahlka, R B; Perrot, F; Piquemal, F; Povinec, P; Přidal, P; Ramachers, Y A; Remoto, A; Reyss, J L; Richards, B; Riddle, C L; Rukhadze, E; Rukhadze, N I; Saakyan, R; Salazar, R; Sarazin, X; Shitov, Yu; Simard, L; Šimkovic, F; Smetana, A; Smolek, K; Smolnikov, A; Söldner-Rembold, S; Soulé, B; Štekl, I; Suhonen, J; Sutton, C S; Szklarz, G; Thomas, J; Timkin, V; Torre, S; Tretyak, Vl I; Tretyak, V I; Umatov, V I; Vanushin, I; Vilela, C; Vorobel, V; Waters, D; Zhukov, S V; Žukauskas, A


    The NEMO-3 experiment at the Modane Underground Laboratory has investigated the double-$\\beta$ decay of $^{48}{\\rm Ca}$. Using $5.25$\\,yr of data recorded with a $6.99\\,{\\rm g}$ sample of $^{48}{\\rm Ca}$, approximately $150$ double-$\\beta$ decay candidate events have been selected with a signal-to-background ratio greater than $3$. The half-life for the two-neutrino double-$\\beta$ decay of $^{48}{\\rm Ca}$ has been measured to be \\mbox{$T^{2\

  9. 裂变产物94Y和95Y半衰期的测定%Half-life determination of fission products 94Y and95Y

    Institute of Scientific and Technical Information of China (English)

    王世联; 白涛; 师全林; 张小林; 凡金龙; 李奇; 刘杰; 卢嘉春; 常永福


    用脉冲反应堆热中子辐照浓缩235U溶液靶,经快速放射化学分离纯化出94Y和95Y溶液,稀释并制备放射性浓度依次相差~10倍的3个测量源.将测量源放置在井式HPGe探测器井内,采用质量归一法测得94Y和95Y的半衰期分别为(19.16±0.05)min和(10.36±0.03)min.%Solutions of enriched235U were irradiated in thermal-neutron flux producedby apulsed reactor,and 94Yand 95Y werc separated chemically from the fission products immediately.The purified solution of 94Y and 95Y is diluted aboutten timgs in sequence to three concentration solutions.Three Sources were prepared with the solutions.The sources are measured,from the lower concentration to higher onc,with a well-type HPGe detector to determine the half-life of94Y and95Y.The determined half-life results arg(19.16±0.05)min and(10.35±0.04)min for94Y and 95Y respectively.

  10. Differential regulation of p21 (waf1) protein half-life by DNA damage and Nutlin-3 in p53 wild-type tumors and its therapeutic implications. (United States)

    Chang, Li-Ju; Eastman, Alan


    DNA damage induces the canonical p53 pathway including elevation of p21 (waf1) resulting in arrest of cell cycle progression. This can protect cells from subsequent Chk1 inhibition. Some p53 wild-type cancer cells such as HCT116 and U2OS exhibit attenuated p21 (waf1) induction upon DNA damage due to translational inhibition, and are incapable of maintaining arrest upon Chk1 inhibition. The purpose of this study was to determine whether this attenuated p21 (waf1) induction also occurred with the non-DNA damaging agent Nutlin-3 which induces p53 by disrupting binding to its negative regulator MDM2. We find that Nutlin-3 circumvented the attenuated induction of p21 (waf1) protein by increasing its half-life which led to G 1 and G 2 arrest in both cell lines. Interestingly, the p21 (waf1) protein half-life remained short on Nutlin-3 in p53 wild-type MCF10A cells; these cells achieve high p21 (waf1) levels through transcriptional upregulation. Consequently, all three p53 wild-type cells but not p53 mutant MDA-MB-231 cancer cells were protected from subsequent incubation with a combination of DNA damage plus a checkpoint inhibitor.

  11. New AMS method to measure the atom ratio {sup 146}Sm/{sup 147}Sm for a half-life determination of {sup 146}Sm

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, N. [Tandem Accelerator Complex, Research Facility Center for Science and Technology, University of Tsukuba (Japan); Paul, M., E-mail: [Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel); Alcorta, M. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Bowers, M.; Collon, P. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556-5670 (United States); Deibel, C.M. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, MI 46624 (United States); DiGiovine, B. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Goriely, S. [Universite Libre de Bruxelles, CP-226, Brussels 1050 (Belgium); Greene, J.P.; Henderson, D.J.; Jiang, C.L. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Kashiv, Y. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556-5670 (United States); Kay, B.P.; Lee, H.Y.; Marley, S.T. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Nakanishi, T. [Faculty of Chemistry, Institute of Science and Engineering, Kanazawa University (Japan); Pardo, R.C.; Patel, N.; Rehm, K.E. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Robertson, D. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556-5670 (United States); and others


    The extinct p-process nuclide {sup 146}Sm (t{sub 1/2} = 103 {+-} 5 Myr) is known to have been present in the Early-Solar System and has been proposed as an astrophysical chronometer. {sup 146}Sm is also intensely used to date meteorite and planetary differentiation processes, enhancing the importance of an accurate knowledge of the {sup 146}Sm half-life. We are engaged in a new determination of the {sup 146}Sm half-life in which the {sup 146}Sm/{sup 147}Sm atom ratio is determined by accelerator mass spectrometry at the ATLAS facility of Argonne National Laboratory. In order to reduce systematic errors in the AMS determination of the {sup 146}Sm/{sup 147}Sm ratios (in the range of 10{sup -7}-10{sup -9}), {sup 146}Sm and {sup 147}Sm ions were alternately counted in the same detector in the focal plane of a gas-filled magnet, respectively in continuous-wave and attenuated mode. Quantitative attenuation is obtained with the 12 MHz pulsed and ns-bunched ATLAS beam by chopping beam pulses with an RF sweeper in a ratio (digitally determined) down to 1:10{sup 6}. The experiments and preliminary results are discussed.

  12. The effective and environmental half-life of {sup 137}Cs at Coral Islands at the former US nuclear test site

    Energy Technology Data Exchange (ETDEWEB)

    Robison, William L. E-mail:; Conrado, Cynthia L.; Bogen, Kenneth T.; Stoker, A. Carol


    The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 ({sup 137}Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of {sup 137}Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of {sup 137}Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of {sup 137}Cs and {sup 90}Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of {sup 137}Cs and {sup 90}Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of {sup 137}Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the {sup 137}Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the {sup 137}Cs/{sup 90}Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the {sup 137}Cs/{sup 90}Sr ratios in soil in 1987 relative to the{sup 137}Cs/{sup 90}Sr ratios at the time of deposition in 1954 is less


    Energy Technology Data Exchange (ETDEWEB)

    Cunningham, B.B.; Asprey, L.B.


    The microgram scale isolation and preparation of pure compounds of americium is described. Data are presented to show that the alpha-half-life of the isotope Am{sup 241} is 490 {+-} 14 years. The absorption spectrum of Am(III) in 1M nitric acid in the range 3500-8000 mu is given. The wave lengths of 10 of the most prominent lines in the copper spark emission spectrum of americium are given to the nearest 0.01 {angstrom}. Evidence is presented to show that the potential for the Am(III)-Am(IV) couple in acid solution is more negative than -2v and that the potential for the Am(II)-Am(III) couple is more positive than +0.9v.

  14. Orthogonal assembly of a designed ankyrin repeat protein-cytotoxin conjugate with a clickable serum albumin module for half-life extension. (United States)

    Simon, Manuel; Frey, Raphael; Zangemeister-Wittke, Uwe; Plückthun, Andreas


    The generation of drug conjugates for safe and effective tumor targeting requires binding proteins tolerant to functionalization by rational engineering. Here, we show that Designed Ankyrin Repeat Proteins (DARPins), a novel class of binding proteins not derived from antibodies, can be used as building blocks for facile orthogonal assembly of bioconjugates for tumor targeting with tailored properties. DARPin Ec1, which targets the Epithelial Cell Adhesion Molecule (EpCAM), was genetically modified with a C-terminal cysteine for conjugation of the small molecule cytotoxin monomethylauristatin F (MMAF). In addition, it was N-terminally functionalized by metabolic introduction of the non-natural amino acid azidohomoalanine to enable linkage of site-specifically dibenzocyclooctyne-modified mouse serum albumin (MSA) for half-life extension using Cu(I)-free click chemistry. The conjugate MSA-Ec1-MMAF was assembled to obtain high yields of a pure and stable drug conjugate as confirmed by various analytical methods and in functional assays. The orthogonality of the assembly led to a defined reaction product and preserved the functional properties of all modules, including EpCAM-specific binding and internalization, FcRn binding mediated by MSA, and cytotoxic potency. Linkage of MMAF to the DARPin increased receptor-specific uptake of the drug while decreasing nonspecific uptake, and further coupling of the conjugate to MSA enhanced this effect. In mice, albumin conjugation increased the serum half-life from 11 min to 17.4 h, resulting in a more than 22-fold increase in the area-under-the-curve (AUC). Our data demonstrate the promise of the DARPin format for facile modular assembly of drug conjugates with improved pharmacokinetic performance for tumor targeting.

  15. Metabolically stable bradykinin B2 receptor agonists enhance transvascular drug delivery into malignant brain tumors by increasing drug half-life

    Directory of Open Access Journals (Sweden)

    Glen Daniel


    -lysine-bradykinin and labradimil increased the blood half-life of Gd-DTPA sufficiently enough to increase significantly the tumor tissue Gd-DTPA area under the time-concentration curve. Conclusion Metabolically stable bradykinin B2 receptor agonists, methionine-lysine-bradykinin and labradimil, enhance the transvascular delivery of small chemotherapy drugs across the BBTB of malignant gliomas by increasing the blood half-life of the co-infused drug. The selectivity of the increase in drug delivery into the malignant glioma tissue, but not into normal brain tissue or skeletal muscle tissue, is due to the inherent porous nature of the BBTB of malignant glioma microvasculature.

  16. Precision measurement of the half-life and the $\\beta$-decay Q value of the superallowed 0$^{+}\\rightarrow$ 0$^{+}\\beta$-decay of $^{38}$Ca

    CERN Multimedia


    We propose to study the $\\beta$-decay of $^{38}$Ca. In a first instance, we intend to perform a high-precision study of the half-life of this nucleus as well as a measurement of its $\\beta$-decay Q-value with ISOLTRAP. At a later stage, we propose to study its decay branches to determine the super-allowed branching ratio with high precision. These measurements are essential to improve our understanding of the theoretical corrections (in particular the $\\delta$c correction factor) needed to calculate the universal Ft value from the ft value determined for individual nuclei. For this nucleus, the correction factor is predicted to increase significantly as compared to the nine well-studied nuclei between $^{10}$C and $^{54}$Co and the model calculations used to determine the corrections, in particular the shell-model calculations, are well under control in this mass region. Therefore, the T$_{Z}$= -1 nuclei between A=18 and A=38 are ideal test cases for the correction factors which limit today the precision on t...

  17. Precision measurement of the half-life and branching ratio of the T=1/2 mirror $\\beta$-decay of $^{37}$K

    CERN Multimedia

    We propose to study the T=1/2 mirror $\\beta$-decay of $^{37}$K. Nuclear mirror $\\beta$-decay is a competitive means to test the electroweak model by means of the high-precision measurement of V$_{ud}$ element of the CKM quark mixing matrix. One key ingredient to obtain V$_{ud}$ is the force of the transition, Ft, which has to be determined with a relative precision below 10$^{−3}$. This quantity is related to the half-life T$_{1/2}$ of the decaying nucleus, the branching ratio BR for this decay and the mass difference between the mother and daughter nucleus (Q value). Another important feature is the mixing ratio $\\rho$ between the Fermi and the Gamow-Teller character of the transition. In most cases, $\\rho$ is the major contributor to the uncertainty on Ft. Available data concerning T$_{1/2}$ and BR of $^{37}$K suffer from a lack of precision that will be easily reduced by a dedicated experiment.

  18. Neutron activation of natural materials in a PWR spectrum: feedback on {sup 116m}In relative γ emission intensities and half-life

    Energy Technology Data Exchange (ETDEWEB)

    Gruel, Adrien; Geslot, Benoit; Di Salvo, Jacques; Blaise, Patrick; Girard, Jean-Michel; Destouches, Christophe [CEA, DEN, SPEx, Cadarache, F-13108 St Paul lez Durance (France)


    During the MAESTRO program, carried out between 2011 and 2014 in MINERVE zero power reactor, common Gen-II and Gen-III light water reactor materials were irradiated. For some of these materials, the decay of their activation products was also measured by γ spectrometry. Initially devoted to the measurement of the integral capture cross section by activation and reactivity-oscillation method, these results can also provide useful information on decay data of various radionuclides. This approach of this experiment led to a common roadmap shared by the Experimental Physics Section and the Henri Becquerel National Laboratory to improve decay data in nuclear data libraries. Results discussed in this paper concern the relative emission intensities of the main γ rays of {sup 116m}In. Six irradiations of samples with various physical forms of {sup nat}In were carried out. Measurements were analyzed using decay data from several evaluations and it is shown that γ ray activities are not consistent. Analyses were carried out to provide new relative γ emission intensities from these measurements. The {sup 116m}In half-life has also been measured and shows a good agreement with existing values. Finally, an overview of the foreseen results on additional decay data from the MAESTRO program is given. (authors)

  19. New limit for the half-life of double beta decay of $^{94}$Zr to the first excited state of $^{94}$Mo

    CERN Document Server

    Dokania, N; Gupta, G; Pal, S; Pillay, R G; Rath, P K; Tretyak, V I; Garai, A; Krishnamoorthy, H; Ghosh, C; Raina, P K; Bhushan, K G


    Double Beta Decay is a phenomenon of fundamental interest for particle physics and the study of these transitions to the excited states is of relevance to the calculation of Nuclear Transition Matrix Element for the process. In the present work, double beta decay of $^{94}$Zr to the $2^{+}_{1}$ excited state of $^{94}$Mo at 871.1 keV is studied using a low background $\\sim$ 250 cm$^3$ HPGe detector. No evidence of this decay was found with a 232 g.y exposure of natural Zirconium. The lower half-life limit obtained for the double beta decay of $\\rm^{94}Zr$ to the $2^{+}_{1}$ excited state of $\\rm^{94}Mo$ is $T_{1/2} > 6.1 \\times 10^{19}$ y at 90\\% C.L. ($T_{1/2} > 2.0 \\times 10^{20}$ y at 68\\% C.L.), a significant improvement by an order of magnitude over the existing experimental limit at 68\\% C.L.

  20. Analytical expression for the α-decay half-life and understanding the data including very long life-times and superheavy nuclei (United States)

    Sahu, Basudeb


    An analytically solvable composite potential that can closely reproduce the combined potential of an α+nucleus system consisting of attractive nuclear and repulsive electrostatic potentials is developed. The exact s-wave solution of the Schrödinger equation with this potential in the interior region and the outside Coulomb wave function are used to give a heuristic expression for the width or half-life of the quasibound state at the accurately determined resonance energy, called the Q value of the decaying system. By using the fact that for a relatively low resonance energy, the quasibound state wave function is quite similar to the bound state wave function where the amplitude of the wave function in the interaction region is very large as compared to the amplitude outside, the resonance energy could easily be calculated from the variation of relative probability densities of inside and outside waves as a function of energy. By considering recent α-decay systems, the applicability of the model is demonstrated with excellent explanations being found for the experimental data of Q values and half-lives of a vast range of masses including superheavy nuclei and nuclei with very long lifetimes (of order 1022 s). Throughout the application, by simply varying the value of a single potential parameter describing the flatness of the barrier, we obtain successful results in cases with as many as 70 pairs of α+daughter nucleus systems.

  1. Ligand-substitution mode capillary electrophoretic reactor: extending capillary electrophoretic reactor toward measurement of slow dissociation kinetics with a half-life of hours. (United States)

    Iki, Nobuhiko; Takahashi, Mariko; Takahashi, Toru; Hoshino, Hitoshi


    A method employing capillary electrophoresis (CE) was developed to determine the rate constant of the very slow spontaneous dissociation of a complex species. The method uses a CE reactor (CER) to electrophoretically separate components from a complex zone and, thus, spontaneously dissociate a complex. The dissociation is accelerated by ligand substitution (LS) involving a competing ligand added to the electrophoretic buffer. The LS-CER method is validated using the dissociation of a Ti(IV)-catechin complex and EDTA as a competing ligand. There is good agreement between the spontaneous dissociation rate constant (k(d) = (1.64 +/- 0.63) x 10(-4) s(-1)) and the rate constant obtained by a conventional batchwise LS reaction (k(d) = (1.43 +/- 0.04) x 10(-4) s(-1)). Furthermore, the usefulness of the method is demonstrated using a Ti(IV)-tiron complex, for which k(d) = (0.51 +/- 0.43) x 10(-4) s(-1), corresponding to a half-life (t(1/2)) of 3.8 h. Notably, a single run of LS-CER for the Ti(IV) complex is completed within 40 min, implying that LS-CER requires a considerably shorter measurement time (roughly equal to t(1/2)) than conventional CER. LS-CER can be widely applied to determine the spontaneous dissociation rates of inorganic diagnostic and therapeutic reagents as well as of biomolecular complexes.

  2. pH-selective mutagenesis of protein-protein interfaces: in silico design of therapeutic antibodies with prolonged half-life. (United States)

    Spassov, Velin Z; Yan, Lisa


    Understanding the effects of mutation on pH-dependent protein binding affinity is important in protein design, especially in the area of protein therapeutics. We propose a novel method for fast in silico mutagenesis of protein-protein complexes to calculate the effect of mutation as a function of pH. The free energy differences between the wild type and mutants are evaluated from a molecular mechanics model, combined with calculations of the equilibria of proton binding. The predicted pH-dependent energy profiles demonstrate excellent agreement with experimentally measured pH-dependency of the effect of mutations on the dissociation constants for the complex of turkey ovomucoid third domain (OMTKY3) and proteinase B. The virtual scanning mutagenesis identifies all hotspots responsible for pH-dependent binding of immunoglobulin G (IgG) to neonatal Fc receptor (FcRn) and the results support the current understanding of the salvage mechanism of the antibody by FcRn based on pH-selective binding. The method can be used to select mutations that change the pH-dependent binding profiles of proteins and guide the time consuming and expensive protein engineering experiments. As an application of this method, we propose a computational strategy to search for mutations that can alter the pH-dependent binding behavior of IgG to FcRn with the aim of improving the half-life of therapeutic antibodies in the target organism.

  3. Research on Half-life Measuring Index of Chinese Psychology Science Based on Bibliometrics%基于文献计量学的我国心理学学科半衰期分析

    Institute of Scientific and Technical Information of China (English)



    文章对心理学学科文献的引用和被引情况进行统计分析,通过学科文献被引半衰期和引用半衰期指标及其相关影响因素的分析,发现:心理学学科引用半衰期明显长于被引半衰期;心理学学科非常注重参考和借鉴国外的研究成果,但引用外文文献的时效相对滞后,说明我国心理学研究落后于国际水平;基础心理学半衰期最长,发展与教育心理学半衰期最短,比较符合偏理论的学科半衰期较长,偏应用的学科半衰期较短的规律。%This paper makes a statistical analysis of research papers' citation. Through analyzing the indexes of half- life of literature and the reference factors, it is found that citing half-life is longer than cited half-life in psychology. It is important to take reference of foreign research achievements in psychology, but the cited foreign papers are lagging, which shows psychology in China lags behind international level. The half-life of basic psychology is longest, while the half-life of development and education psychology is shortest, which shows the rule that half-life of discipline that focus more on theory is longer than the discipline that focus more on application.

  4. Alterative application of five anticonvulsants according to the half life for the treatment of status epilepticus in children with severe viral encephalitis

    Institute of Scientific and Technical Information of China (English)


    BACKGROUND: Traditional subhibernation therapy may easily cause complications, such as respiratory depression and hyportension because of application of chlorpromazine hydrochloride and promethazine in a large dosage.OBJECTIVE: To observe therapeutic effect of modified subhibernation therapy (alterative application of five anticonvulsants according to the half life) on status epilepticus in children with severe viral encephalitis (VE).DESIGN: Contrast observation.SETTING: Department of Pediatrics, the First Hospital of Jilin University.PARTICIPANTS: The participants in present study were 96 patients withsevere viral encephalitis including 52 boys and 44 girls who received treatment in the Department of Pediatrics, the First Hospital of Jilin University from February 2000 to March 2006. All children met the diagnostic criteria of Zhufutong Practice Pediatrics (the seventh edition). Two weeks ago, they ever got upper respiratory infection or enteronitis and so on before the onset, spirit abnormal, behavior disorder, limbs act disorder, vomit, headache, convulsion,nervous system masculine signs such as limbs act disord, autonomic nerve damage manifestation, brain nerve palsy, dysreflexia, meningeal irritation sign, cerebrospinal fluid and electroencephalography (EEG)abnormity. All parents provided the confirmed consent. The patients were randomly divided into control group (n =40) and experimental group (n =56).METHODS: Patients in the control group received anticonvulsion, ice compress and routine treatment. The convulsion was treated with five drugs: 0.5 mg/kg wintermin and phenergan, respectively, 100 g/L chlorpromazine hydrochloride (0.5 mL/kg), 5 mg/kg luminal, 0.3 mg/kg ansiolin. When convulsion attacked,those five drugs were given alternatively; however, those were not given if the convulsion did not attack.Children in the experimental group were treated with improved subhibernation therapy based on routine treatment. The dosages of anticonvulsants were as the

  5. Long circulating half-life and high tumor selectivity of the photosensitizer meta-tetrahydroxyphenylchlorin conjugated to polyethylene glycol in nude mice grafted with a human colon carcinoma. (United States)

    Westerman, P; Glanzmann, T; Andrejevic, S; Braichotte, D R; Forrer, M; Wagnieres, G A; Monnier, P; van den Bergh, H; Mach, J P; Folli, S


    In a mode of nude mice bearing a human colon carcinoma xenograft, the biodistribution and tumor localization of metatetrahydroxyphenylchlorin (m-THPC) coupled to polyethylene glycol (PEG) were compared with those of the free form of this photosensitizer used in photodynamic therapy (PDT). At different times after i.v. injection of both forms of 125I-labeled photosensitizer, m-THPC-PEG gave on average a 2-fold higher tumor uptake than free m-THPC. In addition, at early times after injection, m-THPC-PEG showed a 2-fold longer blood circulating half-life and a 4-fold lower liver uptake than free m-THPC. The tumor to normal tissue ratios of radioactivity concentrations were always higher for m-THPC-PEG than for free m-THPC at any time point studied from 2 to 96 hr post-injection. Significant coefficients of correlation between direct fluorescence measurements and radioactivity counting were obtained within each organ tested. Fluorescence microscopy studies showed that m-THPC-PEG was preferentially localized near the tumor vessels, whereas m-THPC was more diffusely distributed inside the tumor tissue. To verify whether m-THPC-PEG conjugate remained phototoxic in vivo, PDT experiments were performed 72 hr after injection and showed that m-THPC-PEG was as potent as free m-THPC in the induction of tumor regression provided that the irradiation does for m-THPC-PEG conjugate was adapted to a well-tolerated 2-fold higher level. The overall results demonstrate first the possibility of improving the in vivo tumor localization of a hydrophobic dye used for PDT by coupling it to PEG and second that a photosensitizer conjugated to a macromolecule can remain phototoxic in vivo.

  6. Effect of Truncating AUC at 12, 24 and 48 hr When Evaluating the Bioequivalence of Drugs with a Long Half-Life. (United States)

    Moreno, Isabel; Ochoa, Dolores; Román, Manuel; Cabaleiro, Teresa; Abad-Santos, Francisco


    Bioequivalence studies of drugs with a long half-life require long periods of time for pharmacokinetic sampling. The latest update of the European guideline allows the area under the curve (AUC) truncated at 72 hr to be used as an alternative to AUC0-t as the primary parameter. The objective of this study was to evaluate the effect of truncating the AUC at 48, 24 and 12 hr on the acceptance of the bioequivalence criterion as compared with truncation at 72 hr in bioequivalence trials. The effect of truncated AUC on the within-individual coefficient of variation (CVw) and on the ratio of the formulations was also analysed. Twenty-eight drugs were selected from bioequivalence trials. Pharmacokinetic data were analysed using WinNonLin 2.0 based on the trapezoidal method. Analysis of variance (ANOVA) was performed to obtain the ratios and 90% confidence intervals for AUC at different time-points. The degree of agreement of AUC0-72 in relation to AUC0-48 and AUC0-24, according to the Landis and Koch classification, was 'almost perfect'. Statistically significant differences were observed when the CVw of AUC truncated at 72, 48 and 24 hr was compared with the CVw of AUC0-12. There were no statistically significant differences in the AUC ratio at any time-point. Compared to AUC0-72, Pearson's correlation coefficient for mean AUC, AUC ratio and AUC CVw was worse for AUC0-12 than AUC0-24 or AUC0-48. These preliminary results could suggest that AUC truncation at 24 or 48 hr is adequate to determine whether two formulations are bioequivalent.

  7. Studies on the mechanism of the epileptiform activity induced by U18666A. II. concentration, half-life and distribution of radiolabeled U18666A in the brain

    Energy Technology Data Exchange (ETDEWEB)

    Cenedella, R.J.; Sarkar, C.P.; Towns, L.


    The concentration, half-life, and distribution in brain of U18666A, a drug that can drastically alter cerebral lipids and induce a chronic epileptiform state, was determined following both acute and chronic drug administration. U18666A specifically labeled with tritium was prepared by custom synthesis. Brain levels of 1 x 10(-6)M and higher were reached soon after giving an acute 10-mg/kg dose (i.p. or s.c.) of U18666A containing 7-/sup 3/H-U18666A of known specific activity. A steady state concentration of 1 to 2 x 10(-6)M was reached with chronic injection of 10 mg/kg every 4th day, a treatment schedule that results in altered brain lipids and induction of epilepsy if begun soon after birth. The disappearance of U18666A from both brain and serum was described by two similar biexponential processes, a brief rapid clearance (t1/2 . 10 h) and a sustained and much slower one (t1/2 . 65 h). Brain levels of the drug were about 10 times higher than serum at all times examined. Few differences were seen in the regional distribution of radiolabeled drug in brain as determined by both direct analysis and by autoradiographic examination; but the drug did concentrate in lipid-rich subcellular fractions. For example, the synaptosome and myelin fractions each contained about 25-35% of both the total /sup 3/H-labeled drug and total lipid in whole brain. The lipid composition of these fractions was drastically altered in treated animals. In conclusion, the chronic epileptiform state induced by U18666A does not appear to involve localization of the drug in a specific brain region or particular cell type. Rather, the condition could involve localization of the drug in lipid-rich membranes and marked changes in the composition of these membranes.

  8. Use of expression-enhancing terminators in Saccharomyces cerevisiae to increase mRNA half-life and improve gene expression control for metabolic engineering applications. (United States)

    Curran, Kathleen A; Karim, Ashty S; Gupta, Akash; Alper, Hal S


    Control of gene and protein expression of both endogenous and heterologous genes is a key component of metabolic engineering. While a large amount of work has been published characterizing promoters for this purpose, less effort has been exerted to elucidate the role of terminators in yeast. In this study, we characterize over 30 terminators for use in metabolic engineering applications in Saccharomyces cerevisiae and determine mRNA half-life changes to be the major cause of the varied protein and transcript expression level. We demonstrate that the difference in transcript level can be over 6.5-fold even for high strength promoters. The influence of terminator selection is magnified when coupled with a low-expression promoter, with a maximum difference in protein expression of 11-fold between an expression-enhancing terminator and the parent plasmid terminator and over 35-fold difference when compared with a no-terminator baseline. This is the first time that terminators have been investigated in the context of multiple promoters spanning orders of magnitude in activity. Finally, we demonstrate the utility of terminator selection for metabolic engineering by using a mutant xylose isomerase gene as a proof-of-concept. Through pairing an expression-enhancing terminator with a low-expression promoter, we were able to achieve the same phenotypic result as with a promoter considerably higher in strength. Moreover, we can further boost the phenotype of the high-strength promoter by pairing it with an expression-enhancing terminator. This work highlights how terminator elements can be used to control metabolic pathways in the same way that promoters are traditionally used in yeast. Together, this work demonstrates that terminators will be an important part of heterologous gene expression and metabolic engineering for yeast in the future.

  9. First measurements on how pressure affects the half-life of 22Na: Comparison to theory and analog to 40K (United States)

    Lee, K. K.; Nelson, R. O.; Rundberg, R.; Steinle-Neumann, G.


    Radioactive decay plays a central role in planetary sciences as appropriate decay schemes are used to date geological and astronomical processes and radioactivity provides an important source of heat in planetary bodies, both in their early history during accretion and differentiation and also over geological times. The most important isotopes that currently heat the Earth are 40K, 232Th, 235U and 238U. As radioactive decay is a nuclear process it is considered to be insensitive to external factors such as pressure or chemical environment. This has been shown to be true for α, β+ and β- processes, however, electron capture decay is dependent on the electron charge density at the nucleus of a compound, which is sensitive to the external environment. Using high-resolution Ge gamma-ray detectors to make relative measurements with 137Cs and the positron decay of 22Na, we measure how pressure affects the half-life of 22Na due to electron-capture decay. Our systematics look favorable for observing this small effect. We will compare our preliminary measurements with complementary ab-initio all-electron computations using the linearized augmented plane wave method (LAPW). Using 22Na as an analog for 40K, our results suggest that the pressure effect for 40K, combined with the opposing effects of high temperatures, will have little, discernible effect on the heat production in the deep Earth as our predicted changes are smaller than the uncertainties in the total decay constant for 40K. This work was supported in part by the Carnegie/DOE Alliance Center (CDAC), through the Stewardship Science Academic Alliances Program of the U.S. Department of Energy. The LANSCE facility is operated, and portions of this work were performed, by Los Alamos National Security, LLC, funded by the U.S. Department of Energy under Contract No. DE-AC52- 06NA25396.

  10. 长效人白细胞介素4拮抗剂的研究%Interleukin-4 antagonists with longer half-life in plasma

    Institute of Scientific and Technical Information of China (English)

    宋西勇; 唱韶红; 刘波; 巩新; 吴军


    Objective To develop an interleukin-4(IL-4) antagonist named M5-IgG1Fc protein constructed by genetic engineering of antibody Fc fragment-cytokine mutein fusion protein which has a long half-life time in plasma.M5-IgG1 Fc protein binds to IL-4 receptor but cannot activate downstream signalling pathway , which provides a basis for drug develop-ment for allergic diseases .Methods The synthesized interleukin-4 mutant gene ( named M5 ) was cloned into the expres-sion vector pBV220 and transformed into E.coli DH5α.Chimeric gene M5-IgG1Fc obtained by overlap extension (SOE) method was transformed into glycoengineered Pichia pastoris GJK01 through expression vector pPICZαA .Then M5-IgGFc fusion protein was obtained by protein purification after being induced by methanol in 72 hours.The anti-IL-4 biologicial ac-tivity assay of M5 and M5-IgG1 Fc was performed with CTLL-2/IL-4R cells and detected with MTT colormetry .Finally,the half-life time of M5 and M5-IgG1 Fc protein in mice was compared by detecting the remaining amount in plasma with ELISA kit.Results The M5 protein expressed in E.coli and M5-IgG1 Fc fusion protein expressed in P.pastoris GJK01 both had IL-4 antagonistic bioactivity .The EC50 of both, which inhibited 5.6 ×10 -2 nmol/ml of IL-4, were 0.31 ±0.05 and 0.77 ± 0.03 nmol/ml,respectively.The maximum of M5 in plasma at 0.5 h was 5.8 ×10 -2 nmol/ml but the remaining amount was 2.8%of the maximum at 2 h.M5 protein could not be detected after administration at 8 h because of the detection line . The maximum of M5-IgG1 Fc fusion protein was 4.7 ×10 -2 nmol/ml,while fusion protein M5-IgG1 Fc decreased to 4.3%of its maximum at 120 h and could not be detected at 168 h.Conclusion M5 protein has IL-4 antagonistic bioactivity .M5-IgG1 Fc fusion protein expressed in glycoengineered P.pastoris GJK01 has IL-4 antagonistic bioactivity and long retention time in mice,which can be potentially used for treatment of allergic diseases .%目的

  11. Real-time RT-PCR analysis of mRNA decay: half-life of Beta-actin mRNA in human leukemia CCRF-CEM and Nalm-6 cell lines

    Directory of Open Access Journals (Sweden)

    Barredo Julio C


    Full Text Available Abstract Background We describe an alternative method to determine mRNA half-life (t1/2 based on the Real-Time RT-PCR procedure. This approach was evaluated by using the β-actin gene as a reference molecule for measuring of mRNA stability. Results Human leukemia Nalm-6 and CCRF-CEM cells were treated with various concentrations of Actinomycin D to block transcription and aliquots were removed periodically. Total RNA was isolated and quantified using the RiboGreen® fluorescent dye with the VersaFluor Fluorometer System. One μg of total RNA was reverse transcribed and used as template for the amplification of a region of the β-actin gene (231 bp. To generate the standard curve, serial ten-fold dilutions of the pBactin-231 vector containing the cDNA amplified fragment were employed, β-actin mRNAs were quantified by Real-Time RT-PCR using the SYBR® Green I fluorogenic dye and data analyzed using the iCycle iQ system software. Using this method, the β-actin mRNA exhibited a half-life of 6.6 h and 13.5 h in Nalm-6 and CCRF-CEM cells, respectively. The t1/2 value obtained for Nalm-6 is comparable to those estimated from Northern blot studies, using normal human leukocytes (5.5 h. Conclusions We have developed a rapid, sensitive, and reliable method based on Real-Time RT-PCR for measuring mRNA half-life. Our results confirm that β-actin mRNA half-life can be affected by the cellular growth rate.

  12. Shiga toxin type 2 (Stx2), a potential agent of bioterrorism, has a short distribution and a long elimination half-life, and induces kidney and thymus lesions in rats. (United States)

    Liu, Yue-Nan; Wang, Sheng-Han; Li, Tao; Wang, Qin; Tu, Wei; Cai, Kun; Hou, Xiao-Jun; Tian, Ren-Mao; Gao, Xiang; Liu, Hao; Xiao, Le; Shi, Jing; Cheng, Yuan-Guo; Li, Jian-Chun; Wang, Hui


    Shiga toxin type 2, a major virulence factor produced by the Shiga toxin-producing Escherichia coli, is a potential toxin agent of bioterrorism. In this study, iodine-125 (125I) was used as an indicator to describe the in vivo Stx2 biodistribution profile. The rats were injected intravenously (i.v.) with 125I-Stx2 at three doses of 5.1-127.5 μg/kg body weight. Stx2 had a short distribution half-life (t (1/2)α, less than 6 min) and a long elimination half-life in rat. The toxicokinetics of Stx2 in rats was dose dependent and nonlinear. Stx2 concentrations in various tissues were detected at 5-min, 0.5-h, and 72-h postinjection. High radioactivity was found in the lungs, kidneys, nasal turbinates, and sometimes in the eyes, which has never been reported in previous studies. In a preliminary assessment, lesions were found in the kidney and thymus.

  13. I-Xe systematics of the impact plume produced chondrules from the CB carbonaceous chondrites: Implications for the half-life value of 129I and absolute age normalization of 129I-129Xe chronometer (United States)

    Pravdivtseva, O.; Meshik, A.; Hohenberg, C. M.; Krot, A. N.


    0.6 Ma value for 129I half-life. The slopes of I-Xe - Pb-Pb correlation lines plotted for different sets of samples for Shallowater normalization are always ⩽1. Assuming uranium half-life values are correct; this restricts the half-life of 129I to ⩽15.7 Ma.

  14. Biologic

    CERN Document Server

    Kauffman, L H


    In this paper we explore the boundary between biology and the study of formal systems (logic). In the end, we arrive at a summary formalism, a chapter in "boundary mathematics" where there are not only containers but also extainers ><, entities open to interaction and distinguishing the space that they are not. The boundary algebra of containers and extainers is to biologic what boolean algebra is to classical logic. We show how this formalism encompasses significant parts of the logic of DNA replication, the Dirac formalism for quantum mechanics, formalisms for protein folding and the basic structure of the Temperley Lieb algebra at the foundations of topological invariants of knots and links.

  15. Modification of the Fc Region of a Human Anti-oncostatin M Monoclonal Antibody for Higher Affinity to FcRn Receptor and Extension of Half-life in Cynomolgus Monkeys. (United States)

    Nnane, Ivo P; Han, Chao; Jiao, Qun; Tam, Susan H; Davis, Hugh M; Xu, Zhenhua


    The purpose of this study was to evaluate the pharmacokinetics (PK) of anti-oncostatin M (OSM) IgG1 monoclonal antibodies, CNTO 1119 and its Fc variant (CNTO 8212), which incorporates the LS(Xtend) mutation to extend terminal half-life (T1/2 ), after a single intravenous (IV) or subcutaneous (SC) administration in cynomolgus monkeys, and to predict human PK. In study 1, single doses of CNTO 1119 and CNTO 8212 were administered IV or SC at 3 mg/kg to cynomolgus monkeys (n = 3 per group). In study 2, single doses of CNTO 8212 were administered IV at 1, 5 or 20 mg/kg, or SC at 5 mg/kg to cynomolgus monkeys (n = 5 per group). Serial blood samples were collected for assessment of serum concentrations of CNTO 1119 and/or CNTO 8212. A two-compartment population PK model with first-order elimination was utilized to simultaneously describe the serum concentrations of CNTO 1119 and CNTO 8212 over time after IV and SC administration in cynomolgus monkeys. The typical population PK parameter estimates for CNTO 1119 in cynomolgus monkeys were clearance (CL) = 2.81 mL/day/kg, volume of distribution of central compartment (V1 ) = 31.3 mL/kg, volume of distribution of peripheral compartment (V2 ) = 23.3 mL/kg, absolute bioavailability (F) = 0.84 and T1/2 = 13.4 days. In comparison, the typical population PK parameter estimates for CNTO 8212 in cynomolgus monkeys were CL = 1.41 mL/day/kg, V1 = 39.8 mL/kg, V2 = 32.6 mL/kg, F = 0.75 and T1/2 = 35.7 days. The mean CL of CNTO 8212 was ~50% lower compared with that for CNTO 1119 in cynomolgus monkeys. The overall volume of distribution (V1 +V2 ) for CNTO 8212 was about 32% larger compared with that for CNTO 1119, but generally similar to the vascular volume in cynomolgus monkeys. The T1/2 of CNTO 8212 was significantly (p monkeys. Thus, the modification of the Fc portion of an anti-OSM IgG1 mAb for higher FcRn binding affinity resulted in lower systemic clearance and a longer terminal half-life in cynomolgus monkeys. CNTO 8212

  16. Modelling the biological half-life and seasonality of ¹⁴C in Fucus vesiculosus from the east coast of Ireland: implications for the estimation of future trends. (United States)

    Keogh, S M; Cournane, S; León Vintró, L; McGee, E J; Mitchell, P I


    Radiocarbon levels were recorded in Fucus vesiculosus samples collected on a monthly basis over a three-year period at a site on the east coast of Ireland. The resulting data was analysed using a numerical model which estimates the transit times from the Sellafield plant to the sampling location, and the mean availability time of ¹⁴C in seaweed. With the inclusion of a model parameter allowing for seasonal variability in uptake by the Fucus, good correlation was observed between the predicted and measured concentrations. Future temporal trends of ¹⁴C Fucus concentrations along the eastern Irish coastline were modelled with the application of three possible prospective discharge scenarios, predicting ¹⁴C Fucus concentrations to reduce to ambient background levels within 2.5-years of discharges being set to zero. Such projections may prove helpful in assessing the consequences of discharge management and policy making in the context of the OSPAR convention.

  17. The Result of Multiple I-131 Treatments on the Effective Half-Life of Retained Radioactivity in Patients Ablated for Differentiated Thyroid Cancer: Possible Evidence for Thyroid Remnant Function Impairment. (United States)

    Okkalides, Demetrios


    The ablation of differentiated thyroid cancer by ingested I-131 depends on the activity absorbed by the remnant. This depends on the function of the thyroid cells and on the rate that radioactivity is excreted from the blood. The reduction of radioiodine is described by the effective half-life (EHL), which is the time taken to half the retained radioactivity. If the tumor recurs, more treatments are prescribed, often with escalating activities. Patients may receive several treatments during the evolution of the disease, and the total radioactivity administered (TRA) is the sum of all such activities. The patients' archived information permitted the calculation of EHL and TRA. The patient cohort processed here comprised 274 females and 101 males treated during 1997 to 2015. The TRA to the patients ranged between 1.1 and 129.5 GBq (average = 7.93 ± 9.9 GBq) and the EHL varied between 5.06 and 43.87 hours (average = 14.13 ± 5.7 hours). The data were processed as follows: (a) the EHL corresponding to the last treatment of each patient was plotted against TRA to patients who were treated once and to those treated several times for comparison and (b) using a small subgroup of 16 patients who were treated at least 5 times, the EHL and TRA corresponding to each treatment of each patient were plotted. A function of the form y = p-k·ln(x) was fitted on the data in all graphs and k was calculated. For patients treated once, EHL was independent of TRA. A decrease was seen in (a) multitreated patients, with the gradient (k) ranging between -0.541 and -13.880 and (b) 13 out of 16 patients, with the gradient (k) ranging between -5.55 and -31.17, both indicating an impairment of the remnant function, perhaps identified as "stunning." Since this is not avoidable, the uptake may be boosted by splitting the prescribed activity into low radioactivity fractions, which will also reduce patient hospitalization.

  18. Oncology Journals Cited Half - life and Its Connection with Other Indicators Such as Impact Factors and Total Cited Frequen%肿瘤医学期刊被引半衰期及其与影响因子、总被引频次等计量指标的关系

    Institute of Scientific and Technical Information of China (English)



    对《2011年版中国期刊引证报告(扩刊版)》中肿瘤医学期刊被引半衰期、影响因子、引用半衰期、总被引频次、平均引文数等的相关关系进行分析,并对期刊编辑和期刊管理工作提出建议。%The paper analyzes the connection among citated half - life, impact factors, citation half - life, total cited frequency of oncology journals included in " Chinese S & T Journal Citation Report (2011 )", proposes advices on journal editing and management work.

  19. Semiperiodo de la literatura científica en Biblioteconomía y Documentación y la influencia de los aspectos temáticos The half-life of scientific literature in library and information science and the influence of thematic issues

    Directory of Open Access Journals (Sweden)

    J.A. Martínez-Comeche


    Full Text Available Este trabajo presenta el cálculo del semiperiodo o vida media de las referencias en 28 revistas españolas y anglosajonas de Biblioteconomía y Documentación siguiendo la fórmula de Burton y Kebler, durante el año 2006. Se analiza posteriormente la posible relación con los contenidos presentes en las revistas, y se extraen conclusiones sobre qué temas nucleares del área imponen básicamente dicho semiperiodo, dando lugar a lo que puede considerarse como el semiperiodo de la literatura científica en Biblioteconomía y Documentación, y señalando qué temas tienden a aumentar o disminuir dicho semiperiodo cuando están presentes en una determinada revista. De esta forma el semiperiodo podría considerarse un indicio del contenido temático de la revista.Following the formula developed by Burton and Kebler, this paper presents a calculation of the half-life of bibliographical references appearing in twenty-eight English- and Spanish-language Library and Information Science journals in the year 2006. An analysis of the relationship of this phenomenon to content is carried out in order to identify the nuclear topic areas that in turn determine this half-life. Moreover, the paper provides an assessment of those subject areas for each of the journals studied that tend to lengthen or shorten the half-life of a given bibliographic reference. As such, the bibliographic half-life may be considered an indicator of the thematic inclination of a given journal.

  20. Importance of neonatal FcR in regulating the serum half-life of therapeutic proteins containing the Fc domain of human IgG1: a comparative study of the affinity of monoclonal antibodies and Fc-fusion proteins to human neonatal FcR. (United States)

    Suzuki, Takuo; Ishii-Watabe, Akiko; Tada, Minoru; Kobayashi, Tetsu; Kanayasu-Toyoda, Toshie; Kawanishi, Toru; Yamaguchi, Teruhide


    The neonatal FcR (FcRn) binds to the Fc domain of IgG at acidic pH in the endosome and protects IgG from degradation, thereby contributing to the long serum half-life of IgG. To date, more than 20 mAb products and 5 Fc-fusion protein products have received marketing authorization approval in the United States, the European Union, or Japan. Many of these therapeutic proteins have the Fc domain of human IgG1; however, the serum half-lives differ in each protein. To elucidate the role of FcRn in the pharmacokinetics of Fc domain-containing therapeutic proteins, we evaluated the affinity of the clinically used human, humanized, chimeric, or mouse mAbs and Fc-fusion proteins to recombinant human FcRn by surface plasmon resonance analysis. The affinities of these therapeutic proteins to FcRn were found to be closely correlated with the serum half-lives reported from clinical studies, suggesting the important role of FcRn in regulating their serum half-lives. The relatively short serum half-life of Fc-fusion proteins was thought to arise from the low affinity to FcRn. The existence of some mAbs having high affinity to FcRn and a short serum half-life, however, suggested the involvement of other critical factor(s) in determining the serum half-life of such Abs. We further investigated the reason for the relatively low affinity of Fc-fusion proteins to FcRn and suggested the possibility that the receptor domain of Fc-fusion protein influences the structural environment of the FcRn binding region but not of the FcgammaRI binding region of the Fc domain.

  1. Analytical studies by activation. Part A and B: Counting of short half-life radio-nuclides. Part C: Analytical programs for decay curves; Etudes d'analyse par activation. Parties A et B: le comptage des radio-nucleides de periodes courtes. Partie C: programme de depouillement des courbes de decroissance

    Energy Technology Data Exchange (ETDEWEB)

    Junod, E. [Commissariat a l' Energie Atomique Grenoble (France). Centre d' Etudes Nucleaires


    Part A and B: Since a radio-nuclide of short half-life is characterized essentially by the decrease in its activity even while it is being measured, the report begins by recalling the basic relationships linking the half-life the counting time, the counting rate and the number of particles recorded. The second part is devoted to the problem of corrections for counting losses due to the idle period of multichannel analyzers. Exact correction formulae have been drawn up for the case where the short half-life radionuclide is pure or contains only a long half-life radio-nuclide. By comparison, charts have been drawn up showing the approximations given by the so-called 'active time' counting and by the counting involving the real time associated with a measurement of the overall idle period, this latter method proving to be more valid than the former. A method is given for reducing the case of a complex mixture to that of a two-component mixture. Part C: The problems connected with the qualitative and quantitative analysis of the decay curves of a mixture of radioactive sources of which one at least has a short half-life are presented. A mathematical description is given of six basic processes for which some elements of Fortran programs are proposed. Two supplementary programs are drawn up for giving an overall treatment of problems of dosage in activation analysis: one on the basis of a simultaneous irradiation of the sample and of one or several known samples, the other with separate irradiation of the unknown and known samples, a dosimeter (activation, or external) being used for normalizing the irradiation flux conditions. (author) [French] Parties A et B: Un radionucleide de periode courte etant defini specialement par la decroissance de son activite pendant la duree meme du comptage, on rappelle en premiere partie de ce rapport les relations fondamentales qui lient periode, temps de comptage, taux de comptage et nombre d'impulsions enregistrees. La

  2. Quantum Yields of Decomposition and Homo-Dimerization of Solid L-Alanine Induced by 7.2 eV Vacuum Ultraviolet Light Irradiation: An Estimate of the Half-Life of L-Alanine on the Surface of Space Objects (United States)

    Izumi, Yudai; Nakagawa, Kazumichi


    One of the leading hypotheses regarding the origin of prebiotic molecules on primitive Earth is that they formed from inorganic molecules in extraterrestrial environments and were delivered by meteorites, space dust and comets. To evaluate the availability of extraterrestrial amino acids, it is necessary to examine their decomposition and oligomerization rates as induced by extraterrestrial energy sources, such as vacuum ultraviolet (VUV) and X-ray photons and high energy particles. This paper reports the quantum yields of decomposition ((8.2 ± 0.7) × 10-2 photon-1) and homo-dimerization ((1.2 ± 0.3) × 10-3 photon-1) and decomposition of the dimer (0.24 ± 0.06 photon-1) of solid l-alanine (Ala) induced by VUV light with an energy of 7.2 eV. Using these quantum yields, the half-life of l-Ala on the surface of a space object in the present earth orbit was estimated to be about 52 days, even when only photons with an energy of 7.2 eV emitted from the present Sun were considered. The actual half-life of solid l-Ala on the surface of a space object orbit around the present day Earth would certainly be much shorter than our estimate, because of the added effect of photons and particles of other energies. Thus, we propose that l-Ala needs to be shielded from solar VUV in protected environments, such as the interior of a meteorite, within a time scale of days after synthesis to ensure its arrival on the primitive Earth.

  3. Half Life - The divided life of Bruno Maximovitch Pontecorvo

    CERN Document Server

    CERN. Geneva


    When Bruno Pontecorvo fled to the USSR at the height of the Cold War in 1950, half way through his life, the British Government, MI5 and FBI tried to portray him as scientifically insignificant, and to imply that his disappearance posed no threat to the West. In reality Pontecorvo was already one of the leading experts in nuclear physics, and recently declassified papers reveal that a prime agenda of FBI and MI5 was to cover up their errors. . During his time in the USSR he made major contributions to physics, and justified the sobriquet: "Mr Neutrino". This talk will reveal the background to his sudden flight, and also evaluate his work in theoretical physics in the aftermath of his arrival in Dubna. Previously secret documents now show that he proposed the concept of associated production before Gell Mann and Pais, and he had an idea to discover the neutrino at a reactor. He may be considered the father of neutrino astronomy with his successful prediction that neutrinos from a supernova could be detected, b...

  4. A New Value of 93Zr Half-Life

    Institute of Scientific and Technical Information of China (English)


    <正>93Zr is a long-lived pure β emitter with energies of 60.6 keV (97.5%) and 91.4 keV (2.5%). It is produced by both nuclear fission and neutron capture of 92Zr. 93Zr has considerable attention because of its

  5. What Is the Half-Life of Basketball Teams? (United States)

    Hrepic, Zdeslav


    What do basketball teams have in common with radioactive nuclei? It turns out, there is more here than first meets the eye. The National Collegiate Athletic Association (NCAA) basketball tournaments feeds fans' craving when NBA competitions are not in swing, and the college tournament time has been referred to as "March Madness" or…

  6. Cosmic-ray half-life of {sup 144}Pm

    Energy Technology Data Exchange (ETDEWEB)

    Zaerpoor, K.; Dragowsky, M.R.; Krane, K.S. [Physics Department, Oregon State University, Corvallis, Oregon97331 (United States); Chan, Y.D.; Isaac, M.C.; Larimer, R.M.; Macchiavelli, A.O.; Macleod, R.W.; Norman, E.B. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California94720 (United States); DiGregorio, D.E. [Laboratorio TANDAR-CNEA, Buenos Aires, 1429 (Argentina); Hindi, M.M.; Robinson, S.J. [Physics Department, Tennessee Technological University, Cookeville, Tennessee38505 (United States); Miocinovic, P. [Physics Department, University of California, Berkeley, California94720 (United States)


    In order to test the possibility of using {sup 144}Pm as a clock to measure the mean cosmic-ray confinement time in the Galaxy, we counted a highly purified 1.4 {mu}Ci source of this isotope in GAMMASPHERE and searched for its astrophysically interesting {beta}{sup +} decay branch through the observation of positron-annihilation {gamma} rays in coincidence with the characteristic 697-keV {gamma} ray. Analysis of 57 h of source counting and 15 h of background shows no net signal and results in an upper limit of 3.7 of 511-511-697 keV coincident events. From this result we establish a 90{percent} confidence level upper limit on the branch for this decay mode to be 7.4{times}10{sup {minus}6}{percent}. The implications of this result for the {sup 144}Pm cosmic-ray chronometer problem are discussed. {copyright} {ital 1998} {ital The American Physical Society}

  7. Fibroblast Growth Factors: Biology, Function, and Application for Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    Ye-Rang Yun


    Full Text Available Fibroblast growth factors (FGFs that signal through FGF receptors (FGFRs regulate a broad spectrum of biological functions, including cellular proliferation, survival, migration, and differentiation. The FGF signal pathways are the RAS/MAP kinase pathway, PI3 kinase/AKT pathway, and PLCγ pathway, among which the RAS/MAP kinase pathway is known to be predominant. Several studies have recently implicated the in vitro biological functions of FGFs for tissue regeneration. However, to obtain optimal outcomes in vivo, it is important to enhance the half-life of FGFs and their biological stability. Future applications of FGFs are expected when the biological functions of FGFs are potentiated through the appropriate use of delivery systems and scaffolds. This review will introduce the biology and cellular functions of FGFs and deal with the biomaterials based delivery systems and their current applications for the regeneration of tissues, including skin, blood vessel, muscle, adipose, tendon/ligament, cartilage, bone, tooth, and nerve tissues.

  8. Development of controller of acquisition and sample positioner for activation for use in measurements of short half-life radioisotopes; Desenvolvimento de dispositivo movimentador automatizado de amostras com vista a aplicacao em medidas de radioisotopos que possuem curto tempo de meia-vida

    Energy Technology Data Exchange (ETDEWEB)

    Secco, Marcello


    High resolution gamma spectroscopy measurements have several applications. Those involving short half-life radioisotope measurements may present low precision problems when the radioactive source is far from detector end cup and in the very high activity situations also can present accuracy loss due to dead time and pile-up effects. A way to overcome these problems is changing the source detector distance as the activity is decreasing, and thereby maximizing the statistical counting. In the present study, the Controller of Acquisition and Sample Positioner for Activation (CASPA) was developed. It is a low cost and weight device, made with low atomic number materials designed to assist gamma spectroscopy measurements, which is able to control the distance between the source and the detector, even allowing that there is a change of this distance during the measurement process. Because it is automated it optimizes the time of the operator, who has complete freedom to program their routine measurements in the device besides minimizing the radiation dose in the operator. An interface that allow the user control the CASPA system and to program the acquisition system was created. Tests aiming to optimize the operation of CASPA system were carried out and the safety of the CASPA operation was verified, it was not presented any failure during their tests. It was applied the repeatability tests by the acquisition {sup 60}Co standard source and was found that the positioning of automated system has reproduced the results of static system with a 95% of confidence level. (author)

  9. 半衰期为数天的惰性气体和卤素裂变产物在UO2颗粒中的扩散与释放%Diffusion and Release of Noble Gas and Halogen Fission Products With Several Days Half-Life in UO2 Particle

    Institute of Scientific and Technical Information of China (English)



    在考虑吸附效应等物理过程的基础上,得到了裂变产物在UO2颗粒中扩散与释放模型的严格解,并导出了不同反应堆运行状态下裂变产物累积释放份额F(t)、释放-产出比R(t)/B(t)的严格表达式.利用上述结果以及相应的近似解、数值解,对半衰期为数天的惰性气体和卤素裂变产物(131I、131Xem、133Xe和133Xem)在不同堆芯历史条件下的F(t)和R(t)/B(t)进行了比较计算.分析表明,F(t)与R(t)/B(t)的结果均有所差别,但当反应堆运行时间达一定长度后,它们的数值相等.此外,严格解去掉了近似解中不必要的保守性,也比数值解更符合物理实际.%The exact solutions of diffusion and release model of noble gas and halogen fission products in UO2 particle of HTGR were built under the conditions of adsorption effect and other physical processes. The corresponding release fractions (F(t)) and the ratio of release and productive amounts (R (t)/B (t)) of fission products were also derived. Furthermore, the F(t) and R(t)/B(t) of 131I, 131Xem, 133Xe and 133Xem whose half-lifes are several days in UO2 particle with the exact solutions, approximate solutions and corresponding numerical solutions under different temperature histories of reactor core were investigated. The results show that the F(t) and R(t)/B(t) are different in numerical values unless the time of release is long enough. The properties of conservation of exact solutions are much more reasonable than the ones of approximate solutions. It is also found that the results of exact solutions approach the actual working conditions more than the approximate and numerical solutions.

  10. Biological properties of adrenomedullin conjugated with polyethylene glycol. (United States)

    Kubo, Keishi; Tokashiki, Mariko; Kuwasako, Kenji; Tamura, Masaji; Tsuda, Shugo; Kubo, Shigeru; Yoshizawa-Kumagaye, Kumiko; Kato, Johji; Kitamura, Kazuo


    Adrenomedullin (AM) is a vasodilator peptide with pleiotropic effects, including cardiovascular protection and anti-inflammation. Because of these beneficial effects, AM appears to be a promising therapeutic tool for human diseases, while intravenous injection of AM stimulates sympathetic nerve activity due to short-acting potent vasodilation, resulting in increased heart rate and renin secretion. To lessen these acute reactions, we conjugated the N-terminal of human AM peptide with polyethylene glycol (PEG), and examined the biological properties of PEGylated AM in the present study. PEGylated AM stimulated cAMP production, an intracellular second messenger of AM, in cultured human embryonic kidney cells expressing a specific AM receptor in a dose-dependent manner, as did native human AM. The pEC50 value of PEGylated AM was lower than human AM, but no difference was noted in maximum response (Emax) between the PEGylated and native peptides. Intravenous bolus injection of 10nmol/kg PEGylated AM lowered blood pressure in anesthetized rats, but the acute reduction became significantly smaller by PEGylation as compared with native AM. Plasma half-life of PEGylated AM was significantly longer than native AM both in the first and second phases in rats. In summary, N-terminal PEGylated AM stimulated cAMP production in vitro, showing lessened acute hypotensive action and a prolonged plasma half-life in comparison with native AM peptide in vivo.

  11. Research of influential factors on elimination half life of vancomycin in children with severe pneumonia%万古霉素在重症肺炎患儿体内消除半衰期影响因素的研究

    Institute of Scientific and Technical Information of China (English)

    汪洋; 宋新文; 许琼; 张华年; 徐华


    目的:探讨万古霉素在重症肺炎患儿体内消除半衰期的影响因素.方法:测定29例重症肺炎患儿静滴万古霉素后在消除相两个时间点的血药浓度,并以此估算每位患儿万古霉素的消除半衰期t1/2(β).进一步利用SPSS 13.0软件作多元线性回归分析来考察t1/2(β)与患儿性别、年龄、身高、体质量、给药量及各生化指标之间的相关性.结果:万古霉素t1/2(β)与血清肌酐(CRE,X)及天门冬酸氨基转移酶(AST,Y)浓度呈正相关(P<0.05),与其他统计数据无显著相关性.回归方程为:t1/2(β)=0.360X+0.043Y-6.316(r=0.851,P<0.01).结论:万古霉素在重症肺炎患儿体内的消除速率与肝、肾功能密切相关,应监测血药浓度并根据患儿的自身状况来制订个体化给药方案.%OBJECTIVE To investigate the influential factors on elimination half life of vancomycin in children with severe pneumonia. METHODS The serum vancomycin concentrations at two time points on elimination phase after intravenous drip in each one of 29 children with severe pneumonia were determined, and which were used to calculate the elimination half lives of vancomycin (t1/2beta). The correlation between vancomycin t1/2beta and sex, age, body height, body weight and biochemical indexes of patients was analyzed with multiple linear regression method by SPSS (13. 0) software. RESULTS Vancomycin t1/2betawas positive correlated with serum creatinine concentration(CRE) and AST (P<0. 05), but no significant correlation was noted between t1/2beta and other statistical data. The regression equation was t1/2beta = 0. 360CRE + 0. 043AST - 6. 316(r = 0. 851, P>0. 000). CONCLUSION The elimination rate of vancomycin in children with severe pneumonia was closely correlated with liver and kidney functions, so it's necessary to monitor the serum vancomycin concentration and draw up individualized therapy according the body condition of every patient.

  12. 乙型病毒性肝炎肝硬化患者肝功能状况对靶控输注瑞芬太尼药物半衰期和镇痛效果的影响%Effects of Liver Function in Patients with Liver Cirrhosis and Virus B Hepatitis on Drug Half-life and An-algesic Effect of Target Controlled Infusion of Remifentanil

    Institute of Scientific and Technical Information of China (English)

    李晓宁; 张卫


    OBJECTIVE:To explore the safety and effects of liver function in patients with liver cirrhosis following virus B hepatitis(called“hepatitis B”for short)on drug half-life and analgesic effect of target controlled infusion of remifentanil. METH-ODS:100 patients with liver cirrhosis following hepatitis B underwent liver and gallbladder surgery under selective general anesthe-sia were collected from our hospital and divided into group A(mild abnormal liver function)and group B(severe abnormal liver function,3 cases withdrew from the test and 47 cases completed the test),with 50 cases in each group,according to Child-Pugh grading of liver function. Both group were given phenobarbital sodium 0.1 g+scopolamine 0.3 mg intramuscularly 0.5 h before oper-ation;midazolam 0.04 mg/kg+propofol 1.5 mg/kg+atracurium 0.6 mg/kg intravenously;target controlled infusion of Remifentanil hydrochloride for injection during operation with 0.125-0.250 μg/(kg·min). The distribution half-life and the elimination half-life of remifentanil were determined, and temperature pain perception threshold (tPDT) and electrical pain perception threshold (ePDT) were measured immediately after the operation;the occurrence of ADR was observed. RESULTS:The distribution and elimination half-life of remifentanil were (4.52 ± 1.25)min and(24.64 ± 1.30)min in group A and (4.68 ± 1.31)min and(25.45 ± 2.08)min in group B respectively,there was no statistical significance between 2 groups(P>0.05). tPDT and ePDT of group A were(8.88± 1.66)mA and(1.54±0.09)mA respectively,and those of group B were(9.16±1.58)mA and(1.34±0.15)mA,there was no sta-tistical significance between 2 groups (P>0.05). No obvious ADR was found in 2 groups. CONCLUSIONS:The abnormal liver function of patients with liver cirrhosis following hepatitis B have no significant effect on drug half-life and analgesic effect of remi-fentanil with good safety.%目的:探讨乙型病毒性肝炎(以下简称“乙肝”)肝硬化患者

  13. 86Y based PET radiopharmaceuticals: radiochemistry and biological applications. (United States)

    Nayak, Tapan K; Brechbiel, Martin W


    Development of targeted radionuclide therapy with (90)Y labeled antibodies and peptides has gained momentum in the past decade due to the successes of (90)Y-ibritumomab tiuxetan and (90)Y-DOTA-Phe(1)-Tyr(3)-octreotide in treatment of cancer. (90)Y is a pure β(-)-emitter and cannot be imaged for patient-specific dosimetry which is essential for pre-therapeutic treatment planning and accurate absorbed dose estimation in individual patients to mitigate radiation related risks. This review article describes the utility of (86)Y, a positron emitter (33%) with a 14.7-h half-life that can be imaged by positron emission tomography and used as an isotopically matched surrogate radionuclide for (90)Y radiation doses estimations. This review discusses various aspects involved in the development of (86)Y labeled radiopharmaceuticals with the specific emphasis on the radiochemistry and biological applications with antibodies and peptides.

  14. Biological de-activation of granular formulation of a carbamate insecticide Cartap in water under laboratory conditions


    Khalid Abdullah; Ayat U. Awank; Masood K. Khattak; Sumbal Yasmin


    Cartap 4% (Padan 4G™) at different concentrations was evaluated for its biological deactivation in laboratory-conditions. The insecticide at 1.88 ppm or above concentrations showed significant increase in percent of dead fingerlings up to 46 days insecticide aging as compared to the control, while 0.8 ppm and below proved to be sub-lethal concentrations. The LD50 at 0-day (fresh solution) was 0.997 ppm, which gradually rose to 2.074 ppm up to the day 46. The chemical attained half-life in 44....

  15. Applications of post-translational modifications of FoxO family proteins in biological functions

    Institute of Scientific and Technical Information of China (English)

    Ying Zhao; Yachen Wang; Wei-Guo Zhu


    The functions of the FoxO family proteins, in particular their transcriptional activities, are modulated by post-translational modifications (PTMs), including phosphorylation, acetylation, ubiquitination, methylation and glycosylation. These PTMs occur in response to different cellular stresses, which in turn regulate the subcellular localization of FoxO family proteins, as well as their half-life, DNA binding, transcriptional activity and ability to interact with other cellular proteins. In this review, we summarize the role of PTMs of FoxO family proteins in linking their biological and functional relevance with various diseases.%The functions of the FoxO family proteins,in particular their transcriptional activities,are modulated by post-translational modifications (PTMs),including phosphorylation,acetylation,ubiquitination,methylation and glycosylation.These PTMs occur in response to different cellular stresses,which in turn regulate the subceilular localization of FoxO family proteins,as well as their half-life,DNA binding,transcriptional activity and ability to interact with other cellular proteins.In this review,we summarize the role of PTMs of FoxO family proteins in linking their biological and functional relevance with various diseases.

  16. All biology is computational biology (United States)


    Here, I argue that computational thinking and techniques are so central to the quest of understanding life that today all biology is computational biology. Computational biology brings order into our understanding of life, it makes biological concepts rigorous and testable, and it provides a reference map that holds together individual insights. The next modern synthesis in biology will be driven by mathematical, statistical, and computational methods being absorbed into mainstream biological training, turning biology into a quantitative science. PMID:28278152

  17. Stability of glufosfamide in phosphate buffers and in biological samples. (United States)

    Sun, Yuming; Chen, Xiaoyan; Xu, Haiyan; Guan, Zhongmin; Zhong, Dafang


    Glufosfamide is a new, potential chemotherapeutic agent currently under investigation. Stability of glufosfamide was investigated in sodium phosphate buffers with different pH and temperature and in biological samples. Glufosfamide and isophosphamide mustard were quantified simultaneously using a liquid chromatography-ion trap mass spectrometric method; precision and accuracy were within 15% for each analyte. Glufosfamide was stable in neutral buffers, but decomposed to form isophosphoramide mustard under acidic and basic conditions, which was pH- and temperature-dependent. The stability of glufosfamide varied in different biological samples. Results indicated that glufosfamide was unstable in some biological samples, such as the small intestine, smooth muscles, pancreas and urine, especially in the small intestine homogenate, with a half-life of 1.1 h. But the pH (<8) and beta-glucosidase of the tissue homogenate was found to have negligible contribution to the degradation of glufosfamide. The enzymatic inhibition experiment with the specific inhibitor, saccharo-1,4-lactone, demonstrated that it was glucuronidase that resulted in the degradation of glufosfamide in small intestine homogenate. Methanol was recommended to be used to homogenize the tissue in an ice water bath, and the container for urine collection should also be maintained in an ice water bath, and all the biological samples collected should be preserved in frozen condition until analysis.

  18. Synthesis, biological distribution and radiation dosimetry of Te-123m analogues of hexadecenoic acid

    Energy Technology Data Exchange (ETDEWEB)

    Basmadjian, G.P.; Ice, R.D. (Oklahoma Univ., Oklahoma City (USA). College of Pharmacy); Mills, S.L. (Tennessee Univ., Memphis (USA). College of Pharmacy)


    The synthesis and biological distribution of four Te-123m analogues of hexadecenoic acid in rats, rabbits and dogs were described for use as possible myocardial imaging agents. The heart-to-blood ratios ranged from 0.13 for 3-telluranonadecenoic acid in rats at 5 mins to 6.25 for 18-methyl-17-tellura-9-nonadecenoic acid in dogs at 24 hrs. The biological half-life of the Te-123m labelled fatty acids ranged from 26 to 583 hrs in the hearts of the test animals. These Te-123m fatty acids were retained in the heart longer than radioiodinated fatty acids and have acceptable absorbed doses to the various target organs.

  19. Quinic acid is a biologically active component of the Uncaria tomentosa extract C-Med 100. (United States)

    Akesson, Christina; Lindgren, Hanna; Pero, Ronald W; Leanderson, Tomas; Ivars, Fredrik


    We have previously reported that the C-Med 100 extract of the plant Uncaria tomentosa induces prolonged lymphocyte half life and hence increased spleen cell number in mice receiving the extract in their drinking water. Further, the extract induces cell proliferation arrest and inhibits activation of the transcriptional regulator nuclear factor kappaB (NF-kappaB) in vitro. We now report that mice exposed to quinic acid (QA), a component of this extract, had significantly increased number of spleen cells, thus recapitulating the in vivo biological effect of C-Med 100 exposure. Commercially supplied QA (H(+) form) did not, however, inhibit cell proliferation in vitro, while the ammonia-treated QA (QAA) was a potent inhibitor. Both QA and QAA inhibited NF-kappaB activity in exposed cells at similar concentrations. Thus, our present data identify QA as a candidate component for both in vivo and in vitro biological effects of the C-Med 100 extract.

  20. Natural Biological Attenuation of Benzene in Groundwater

    Institute of Scientific and Technical Information of China (English)


    Benzene has been found in subsurface unsaturated soil and groundwater beneath a petro-chemical plant. Although the groundwater contained several mg/L of benzene in the area immediately beneath the source, benzene was not detected in monitoring wells approximately 800m down stream. All kinds of physical processes such as adsorption and advection/dispersion are considered to account for the observed attenuation. The results indicated that the attenuation was primarily due to natural biological processes occurring within the aquifer. The evidence for the natural bioremediation of benzene from the groundwater included: (1) analysis of groundwater chemistry, (2) laboratory studies demonstrating benzene biodegradation in aquifer samples, and (3) computer simulations examining benzene transport. Laboratory experiments indicated that for conditions similar to those in the plume, the aerobic degradation of benzene by the naturally occurring microorganisms in the polluted groundwater samples was quite rapid with a half-life time of from 5 to 15 days. In situ analyses indicated the level of dissolved oxygen in the groundwater was over 2mg/L. Thus, oxygen should not limit the biodegradation. In fact, the benzene was also shown to degrade under anaerobic conditions. The results from the modeling simulations indicate that biodegradation is the dominant process influencing attenuation of the benzene.

  1. Biological computation

    CERN Document Server

    Lamm, Ehud


    Introduction and Biological BackgroundBiological ComputationThe Influence of Biology on Mathematics-Historical ExamplesBiological IntroductionModels and Simulations Cellular Automata Biological BackgroundThe Game of Life General Definition of Cellular Automata One-Dimensional AutomataExamples of Cellular AutomataComparison with a Continuous Mathematical Model Computational UniversalitySelf-Replication Pseudo Code Evolutionary ComputationEvolutionary Biology and Evolutionary ComputationGenetic AlgorithmsExample ApplicationsAnalysis of the Behavior of Genetic AlgorithmsLamarckian Evolution Genet

  2. [Biological weapons]. (United States)

    Kerwat, K; Becker, S; Wulf, H; Densow, D


    Biological weapons are weapons of mass destruction that use pathogens (bacteria, viruses) or the toxins produced by them to target living organisms or to contaminate non-living substances. In the past, biological warfare has been repeatedly used. Anthrax, plague and smallpox are regarded as the most dangerous biological weapons by various institutions. Nowadays it seems quite unlikely that biological warfare will be employed in any military campaigns. However, the possibility remains that biological weapons may be used in acts of bioterrorism. In addition all diseases caused by biological weapons may also occur naturally or as a result of a laboratory accident. Risk assessment with regard to biological danger often proves to be difficult. In this context, an early identification of a potentially dangerous situation through experts is essential to limit the degree of damage.

  3. Is synthetic biology mechanical biology? (United States)

    Holm, Sune


    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  4. Computational biology

    DEFF Research Database (Denmark)

    Hartmann, Lars Røeboe; Jones, Neil; Simonsen, Jakob Grue


    Computation via biological devices has been the subject of close scrutiny since von Neumann’s early work some 60 years ago. In spite of the many relevant works in this field, the notion of programming biological devices seems to be, at best, ill-defined. While many devices are claimed or proved t...

  5. A Critical Role for Cysteine 57 in the Biological Functions of Selenium Binding Protein-1

    Directory of Open Access Journals (Sweden)

    Qi Ying


    Full Text Available The concentration of selenium-binding protein1 (SBP1 is often lower in tumors than in the corresponding tissue and lower levels have been associated with poor clinical outcomes. SBP1 binds tightly selenium although what role selenium plays in its biological functions remains unknown. Previous studies indicated that cysteine 57 is the most likely candidate amino acid for selenium binding. In order to investigate the role of cysteine 57 in SBP1, this amino acid was altered to a glycine and the mutated protein was expressed in human cancer cells. The SBP1 half-life, as well as the cellular response to selenite cytotoxicity, was altered by this change. The ectopic expression of SBP1GLY also caused mitochondrial damage in HCT116 cells. Taken together, these results indicated that cysteine 57 is a critical determinant of SBP1 function and may play a significant role in mitochondrial function.

  6. Compilation of selected marine radioecological data for the US Subseabed Program: Summaries of available radioecological concentration factors and biological half-lives

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, L.S.; Marietta, M.G.; Jackson, D.W.


    The US Subseabed Disposal Program has compiled an extensive concentration factor and biological half-life data base from the international marine radioecological literature. A microcomputer-based data management system has been implemented to provide statistical and graphic summaries of these data. The data base is constructed in a manner which allows subsets to be sorted using a number of interstudy variables such as organism category, tissue/organ category, geographic location (for in situ studies), and several laboratory-related conditions (e.g., exposure time and exposure concentration). This report updates earlier reviews and provides summaries of the tabulated data. In addition to the concentration factor/biological half-life data base, we provide an outline of other published marine radioecological works. Our goal is to present these data in a form that enables those concerned with predictive assessment of radiation dose in the marine environment to make a more judicious selection of data for a given application. 555 refs., 19 figs., 7 tabs.

  7. Studies of the electronic structure and biological activity of chosen 1,4-benzodiazepines by {sup 35}Cl NQR spectroscopy and DFT calculations

    Energy Technology Data Exchange (ETDEWEB)

    Bronisz, K. [Department of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland); Ostafin, M. [Department of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland)], E-mail:; Poleshchuk, O. Kh. [Department of Chemistry, Tomsk Pedagogical University, Komsomolskii 75, 634041 Tomsk (Russian Federation); Mielcarek, J. [Faculty of Pharmacy, University of Medical Sciences, Grunwaldzka 6, 60-780 Poznan (Poland); Nogaj, B. [Department of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland)


    Selected derivatives of 1,4-benzodiazepine: lorazepam, lormetazepam, oxazepam and temazepam, used as active substances in anxiolytic drugs, have been studied by {sup 35}Cl NQR method in order to find the correlation between electronic structure and biological activity. The {sup 35}Cl NQR resonance frequencies ({nu} {sub Q}) measured at 77 K have been correlated with the following parameters characterising their biological activity: biological half-life period (t {sub 0.5}), affinity to benzodiazepine receptor (IC{sub 50}) and mean dose equivalent. The results of experimental study of some benzodiazepine derivatives by nuclear quadrupole resonance of {sup 35}Cl nuclei are compared with theoretical results based on DFT calculations which were carried out by means of Gaussian'98 W software.

  8. Studies of the electronic structure and biological activity of chosen 1,4-benzodiazepines by 35Cl NQR spectroscopy and DFT calculations (United States)

    Bronisz, K.; Ostafin, M.; Poleshchuk, O. Kh.; Mielcarek, J.; Nogaj, B.


    Selected derivatives of 1,4-benzodiazepine: lorazepam, lormetazepam, oxazepam and temazepam, used as active substances in anxiolytic drugs, have been studied by 35Cl NQR method in order to find the correlation between electronic structure and biological activity. The 35Cl NQR resonance frequencies ( νQ) measured at 77 K have been correlated with the following parameters characterising their biological activity: biological half-life period ( t0.5), affinity to benzodiazepine receptor (IC 50) and mean dose equivalent. The results of experimental study of some benzodiazepine derivatives by nuclear quadrupole resonance of 35Cl nuclei are compared with theoretical results based on DFT calculations which were carried out by means of Gaussian'98 W software.

  9. Assessment of alginate hydrogel degradation in biological tissue using viscosity-sensitive fluorescent dyes (United States)

    Shkand, Tatiana V.; Chizh, Mykola O.; Sleta, Iryna V.; Sandomirsky, Borys P.; Tatarets, Anatoliy L.; Patsenker, Leonid D.


    The main goal of this study is to investigate a combination of viscosity-sensitive and viscosity-insensitive fluorescent dyes to distinguish different rheological states of hydrogel based biostructural materials and carriers in biological tissues and to assess their corresponding location areas. The research is done in the example of alginate hydrogel stained with viscosity-sensitive dyes Seta-470 and Seta-560 as well as the viscosity-insensitive dye Seta-650. These dyes absorb/emit at 469/518, 565/591 and 651/670 nm, respectively. The rheological state of the alginate, the area of the fluorescence signal and the mass of the dense alginate versus the calcium gluconate concentration utilized for alginate gelation were studied in vitro. The most pronounced change in the fluorescence signal area was found at the same concentrations of calcium gluconate (below ~1%) as the change in the alginate plaque mass. The stained alginate was also implanted in situ in rat hip and myocardium and monitored using fluorescence imaging. In summary, our data indicate that the viscosity sensitive dye in combination with the viscosity-insensitive dye allow tracking the biodegradation of the alginate hydrogel and determining the rheological state of hydrogel in biological tissue, which both should have relevance for research and clinical applications. Using this method we estimated the half-life of the dense alginate hydrogel in a rat hip to be in the order of 4 d and about 6-8 d in rat myocardium. The half-life of the dense hydrogel in the myocardium was found to be long enough to prevent aneurysm rupture of the left ventricle wall, one of the more severe complications of the early post-infarction period.

  10. Biological Oceanography (United States)

    Dyhrman, Sonya


    The ocean is arguably the largest habitat on the planet, and it houses an astounding array of life, from microbes to whales. As a testament to this diversity and its importance, the discipline of biological oceanography spans studies of all levels of biological organization, from that of single genes, to organisms, to their population dynamics. Biological oceanography also includes studies on how organisms interact with, and contribute to, essential global processes. Students of biological oceanography are often as comfortable looking at satellite images as they are electron micrographs. This diversity of perspective begins the textbook Biological Oceanography, with cover graphics including a Coastal Zone Color Scanner image representing chlorophyll concentration, an electron micrograph of a dinoflagellate, and a photograph of a copepod. These images instantly capture the reader's attention and illustrate some of the different scales on which budding oceanographers are required to think. Having taught a core graduate course in biological oceanography for many years, Charlie Miller has used his lecture notes as the genesis for this book. The text covers the subject of biological oceanography in a manner that is targeted to introductory graduate students, but it would also be appropriate for advanced undergraduates.

  11. Quantum Biology

    Directory of Open Access Journals (Sweden)

    Alessandro Sergi


    Full Text Available A critical assessment of the recent developmentsof molecular biology is presented.The thesis that they do not lead to a conceptualunderstanding of life and biological systems is defended.Maturana and Varela's concept of autopoiesis is briefly sketchedand its logical circularity avoided by postulatingthe existence of underlying living processes,entailing amplification from the microscopic to the macroscopic scale,with increasing complexity in the passage from one scale to the other.Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces,is criticized. It is suggested that the correct interpretationof quantum dispersion forces (van der Waals, hydrogen bonding, and so onas quantum coherence effects hints at the necessity of includinglong-ranged forces (or mechanisms for them incondensed matter theories of biological processes.Some quantum effects in biology are reviewedand quantum mechanics is acknowledged as conceptually important to biology since withoutit most (if not all of the biological structuresand signalling processes would not even exist. Moreover, it is suggested that long-rangequantum coherent dynamics, including electron polarization,may be invoked to explain signal amplificationprocess in biological systems in general.

  12. Foldit Biology (United States)


    Report 8/1/2013-7/31/2015 4. TITLE AND SUBTITLE Sa. CONTRACT NUMBER Foldit Biology NOOO 14-13-C-0221 Sb. GRANT NUMBER N/A Sc. PROGRAM ELEMENT...Include area code) Unclassified Unclassified Unclassified (206) 616-2660 Zoran Popović Foldit Biology (Task 1, 2, 3, 4) Final Report...Period Covered by the Report August 1, 2013 – July 31, 2015 Date of Report: July 31, 2015 Project Title: Foldit Biology Contract Number: N00014-13

  13. N-glycosylation increases the circulatory half-life of human growth hormone

    DEFF Research Database (Denmark)

    Flintegaard, Thomas V; Thygesen, Peter; Rahbek-Nielsen, Henrik


    Therapeutic use of recombinant GH typically involves daily sc injections. We examined the possibilities for prolonging the in vivo circulation of GH by introducing N-glycans. Human GH variants with a single potential N-glycosylation site (N-X-S/T) introduced by site-directed mutagenesis were expr...

  14. Average and recommended half-life values for two neutrino double beta decay: upgrade'05

    CERN Document Server

    Barabash, A S


    All existing ``positive'' results on two neutrino double beta decay in different nuclei were analyzed. Using the procedure recommended by the Particle Data Group, weighted average values for half-lives of $^{48}$Ca, $^{76}$Ge, $^{82}$Se, $^{96}$Zr, $^{100}$Mo, $^{100}$Mo - $^{100}$Ru ($0^+_1$), $^{116}$Cd, $^{150}$Nd, $^{150}$Nd - $^{150}$Sm ($0^+_1$) and $^{238}$U were obtained. Existing geochemical data were analyzed and recommended values for half-lives of $^{128}$Te, $^{130}$Te and $^{130}$Ba are proposed. We recommend the use of these results as presently the most precise and reliable values for half-lives.

  15. Average and recommended half-life values for two neutrino double beta decay: upgrade-09

    CERN Document Server

    Barabash, A S


    All existing ``positive'' results on two neutrino double beta decay in different nuclei were analyzed. Using the procedure recommended by the Particle Data Group, weighted average values for half-lives of $^{48}$Ca, $^{76}$Ge, $^{82}$Se, $^{96}$Zr, $^{100}$Mo, $^{100}$Mo - $^{100}$Ru ($0^+_1$), $^{116}$Cd, $^{130}$Te, $^{150}$Nd, $^{150}$Nd - $^{150}$Sm ($0^+_1$) and $^{238}$U were obtained. Existing geochemical data were analyzed and recommended values for half-lives of $^{128}$Te, $^{130}$Te and $^{130}$Ba are proposed. We recommend the use of these results as presently the most precise and reliable values for half-lives.

  16. Average and recommended half-life values for two neutrino double beta decay: upgrade-2013

    CERN Document Server

    Barabash, A S


    All existing positive results on two neutrino double beta decay in different nuclei were analyzed. Using the procedure recommended by the Particle Data Group, weighted average values for half-lives of $^{48}$Ca, $^{76}$Ge, $^{82}$Se, $^{96}$Zr, $^{100}$Mo, $^{100}$Mo - $^{100}$Ru ($0^+_1$), $^{116}$Cd, $^{130}$Te, $^{136}$Xe, $^{150}$Nd, $^{150}$Nd - $^{150}$Sm ($0^+_1$) and $^{238}$U were obtained. Existing geochemical data were analyzed and recommended values for half-lives of $^{128}$Te and $^{130}$Ba are proposed. I recommend the use of these results as the most currently reliable values for half-lives.

  17. Investigations of short half-life states from SF of {sup 252}Cf

    Energy Technology Data Exchange (ETDEWEB)

    Fong, D.; Hwang, J.K.; Ramayya, A.V.; Hamilton, J.H.; Beyer, C.J.; Li, K.; Gore, P.M.; Jones, E.F.; Luo, Y.X. [Vanderbilt University, Physics Department, Nashville, TN (United States); Rasmussen, J.O.; Wu, S.C.; Lee, I.Y.; Fallon, P.; Ginter, T.N. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Zhu, S.J. [Tsinghua University, Department of Physics, Beijing (China); Stoyer, M.A.; Asztalos, S.J. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Cole, J.D. [Idaho National Engineering and Environmental Laboratory, Idaho Falls, ID (United States); Ter-Akopian, G.M.; Daniel, A. [Joint Institute for Nuclear Research, Flerov Laboratory for Nuclear Reactions, Dubna (Russian Federation)


    By using different time-gated triple {gamma} coincidence data, the half-lives (T{sub 1/2}) of several short lived states in neutron-rich nuclei have been studied. The first excited states in the ground state bands often decay by delayed {gamma} emission. By creating triple {gamma} coincidence spectra with time windows of 8, 16, 20, 28, and 48 ns, we have studied states with half-lives below 10 ns. The estimated half-lives of {sup 102}Zr, {sup 137}Xe, and {sup 143}Ba are in reasonable agreement with previously reported values. We extract the first estimates of the half lives of the 2{sup +} states in {sup 104}Zr and {sup 152}Ce. (orig.)

  18. Systematics of alpha decay half-life: new evaluations for alpha-emitter nuclides

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, E.L.; Rodrigues, M.M.N.; Duarte, S.B.; Tavares, O.A.P. E-mail:


    A semiempirical model based on the quantum mechanical tunnelling mechanism of alpha emission from nuclei has been used to systematize the alpha decay half-lives of a set of 336 nuclides, comprising all the alpha-emitter nuclides whose T{sub 1/2} {sup a}lpha-data for ground-state to ground-state transitions of mutual angular momentum l = 0 are known. With a minimum of data rejection (only {approx} 5% of cases), the procedure has been successful in reproducing quite satisfactorily (within a factor {approx} 2) most of the cases ({approx} 80%) investigated. The few significant discrepancies found between measured and calculated results are analysed and discussed. Also reported is the prediction from the model for possible new alpha-emitter nuclides, namely {sup 180} W, {sup 184} Os, and {sup 228} Ra for which cases the calculated partial alpha decay half-lives fall within the range of half-lives measurable by the current techniques. (author)

  19. The mysteriously variable half-life of dissolved organic matter in aquatic ecosystems: artefact or insight? (United States)

    Evans, Chris; Fovet, Ophelie; Jones, Tim; Jones, Davey; Moldan, Filip; Futter, Martyn


    Dissolved organic matter (DOM) fluxes from land to water represent an important loss term in the terrestrial carbon balance, a major pathway in the global carbon cycle, a significant influence on aquatic light, nutrient and energy regimes, and an important concern for drinking water production. Although freshwaters are now recognised as zones of active carbon cycling, rather than passive conduits for carbon transport, evidence regarding the magnitude of, and controls on, DOM cycling in aquatic systems is incomplete and in some cases seemingly contradictory, with DOM 'half-lives' ranging from a few days to many years. Bringing together experimental, isotopic, catchment mass balance and modelling data, we suggest that apparently conflicting results can be reconciled through understanding of differences in: i) the terrestrial sources of DOM within heterogeneous landscapes, and consequent differences in its reactivity and stoichiometry; ii) experimental methodologies (i.e. which reactions are actually being measured), and iii) the extent of prior transformation of DOM upstream of the point of study. We argue that rapid photo-degradation, particularly of peat-derived DOM, is a key process in headwaters, whilst apparently slow DOM turnover in downstream, agriculturally-influenced lakes and rivers can partly be explained by the offsetting effect of in situ DOM production. This production appears to be strongly constrained by nutrient supply, thus linking DOM turnover and composition to the supply of inorganic nutrient inputs from diffuse agricultural pollution, and also providing a possible mechanistic link between aquatic DOM production and terrestrial DOM breakdown via the mineralisation and re-assimilation of organic nutrients. A more complete conceptual understanding of these interlinked processes will provide an improved understanding of the sources and fate of aquatic DOM, its role in the global carbon cycle, and the impact of anthropogenic activities, for example in relation to drinking water supplies and land management.

  20. "半条命"当选最佳%Half-Life 2 Voted Best

    Institute of Scientific and Technical Information of China (English)



    @@ As much as Hollywood critics tend to spurn(弃绝)movies involving exploding zombies(巫毒崇拜), video game critics appear to love them. A game centered on the adventures of a scientist who blasts( 毁灭 ) an invading army of zombies has bested a field of rival offerings-including a driving adventure and a game first developed as a U. S. Army training tool-to win a coveted(觊觎的) award from game commentators.

  1. Half-Life Learning Curves in the Defense Acquisition Life Cycle (United States)


    learning include Smith (1989); Belkaoui (1976, 1986); Nanda (1979); Pegels (1976); Richardson (1978); Towill, and Kaloo (1978); Womer (1979, 1981, 1984...analysis adjusted for learning. Management Science, 24(2), 149–160. Nanda , R. (1979). Using learning curves in integration of production resources

  2. Use of daily detector verification data for isotopical half-life determination

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Vitor C.; Zahn, Guilherme S.; Genezini, Frederico A.; Ticianelli, Regina B.; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP. P.O. Box 11049, Sao Paulo, 05422-970 (Brazil)


    In this work, the possibility of using data fromthe daily detector verification routines performed at the Neutron Activation Laboratory of IPEN to determine precise values for the half-lives of {sup 57}Co and {sup 60}Co was evaluated. For this purpose data from 4 of the laboratory's detectors, some spanning for more than 9 years, were inspected, separated in consistent groups, and then analyzed using a robust least-squares fit procedure in order to determine the half-lives. The results allowed for a discussion on the possibilities and limitations of the use of these data for the determination of half-lives.

  3. Biological preconcentrator (United States)

    Manginell, Ronald P.; Bunker, Bruce C.; Huber, Dale L.


    A biological preconcentrator comprises a stimulus-responsive active film on a stimulus-producing microfabricated platform. The active film can comprise a thermally switchable polymer film that can be used to selectively absorb and desorb proteins from a protein mixture. The biological microfabricated platform can comprise a thin membrane suspended on a substrate with an integral resistive heater and/or thermoelectric cooler for thermal switching of the active polymer film disposed on the membrane. The active polymer film can comprise hydrogel-like polymers, such as poly(ethylene oxide) or poly(n-isopropylacrylamide), that are tethered to the membrane. The biological preconcentrator can be fabricated with semiconductor materials and technologies.

  4. Biology Notes. (United States)

    School Science Review, 1981


    Outlines a variety of laboratory procedures, techniques, and materials including construction of a survey frame for field biology, a simple tidal system, isolation and applications of plant protoplasts, tropisms, teaching lung structure, and a key to statistical methods for biologists. (DS)

  5. (Biological dosimetry)

    Energy Technology Data Exchange (ETDEWEB)

    Preston, R.J.


    The traveler attended the 1st International Conference on Biological Dosimetry in Madrid, Spain. This conference was organized to provide information to a general audience of biologists, physicists, radiotherapists, industrial hygiene personnel and individuals from related fields on the current ability of cytogenetic analysis to provide estimates of radiation dose in cases of occupational or environmental exposure. There is a growing interest in Spain in biological dosimetry because of the increased use of radiation sources for medical and occupational uses, and with this the anticipated and actual increase in numbers of overexposure. The traveler delivered the introductory lecture on Biological Dosimetry: Mechanistic Concepts'' that was intended to provide a framework by which the more applied lectures could be interpreted in a mechanistic way. A second component of the trip was to provide advice with regard to several recent cases of overexposure that had been or were being assessed by the Radiopathology and Radiotherapy Department of the Hospital General Gregorio Maranon'' in Madrid. The traveler had provided information on several of these, and had analyzed cells from some exposed or purportedly exposed individuals. The members of the biological dosimetry group were referred to individuals at REACTS at Oak Ridge Associated Universities for advice on follow-up treatment.

  6. Marine Biology (United States)

    Dewees, Christopher M.; Hooper, Jon K.


    A variety of informational material for a course in marine biology or oceanology at the secondary level is presented. Among the topics discussed are: food webs and pyramids, planktonic blooms, marine life, plankton nets, food chains, phytoplankton, zooplankton, larval plankton and filter feeders. (BT)

  7. Scaffolded biology. (United States)

    Minelli, Alessandro


    Descriptions and interpretations of the natural world are dominated by dichotomies such as organism vs. environment, nature vs. nurture, genetic vs. epigenetic, but in the last couple of decades strong dissatisfaction with those partitions has been repeatedly voiced and a number of alternative perspectives have been suggested, from perspectives such as Dawkins' extended phenotype, Turner's extended organism, Oyama's Developmental Systems Theory and Odling-Smee's niche construction theory. Last in time is the description of biological phenomena in terms of hybrids between an organism (scaffolded system) and a living or non-living scaffold, forming unit systems to study processes such as reproduction and development. As scaffold, eventually, we can define any resource used by the biological system, especially in development and reproduction, without incorporating it as happens in the case of resources fueling metabolism. Addressing biological systems as functionally scaffolded systems may help pointing to functional relationships that can impart temporal marking to the developmental process and thus explain its irreversibility; revisiting the boundary between development and metabolism and also regeneration phenomena, by suggesting a conceptual framework within which to investigate phenomena of regular hypermorphic regeneration such as characteristic of deer antlers; fixing a periodization of development in terms of the times at which a scaffolding relationship begins or is terminated; and promoting plant galls to legitimate study objects of developmental biology.

  8. Biology Notes. (United States)

    School Science Review, 1984


    Presents information on the teaching of nutrition (including new information relating to many current O-level syllabi) and part 16 of a reading list for A- and S-level biology. Also includes a note on using earthworms as a source of material for teaching meiosis. (JN)

  9. Somatostatin, somatostatin analogs and somatostatin receptor dynamics in the biology of cancer progression. (United States)

    Ruscica, M; Arvigo, M; Steffani, L; Ferone, D; Magni, P


    The pharmacological effects (i.e., inhibition of endocrine secretion and cell proliferation) mediated by the hormone somatostatin (SRIF) are derived from its universal high-affinity binding to five different G proteincoupled receptors (GPCRs), named sst1-5. However, SRIF has a half-life of less than 3 min, whereas the available mono- and bi-specific SRIF preferential analogs show prolonged half-life and increased potency. These compounds may control tumor development, cell proliferation and metastatization by direct actions, including cell division arrest in G0/G1 phase (i.e., induction of cyclin-dependent kinase inhibitor p27(kip1) or p21(Cip1)), induction of apoptosis (i.e., induction of p53 and Bax) and suppression of cell invasion. Along with these direct actions on the biology of cancer progression, in vivo SRIF analogs may also regulate tumor growth through indirect actions, by suppressing the secretion of growth-promoting hormones and growth factors and angiogenesis. Interestingly, when ssts are co-expressed, they may interact forming homo- or heterodimers, also with other GPCRs such as type 2 dopamine receptor and the μ-opioid receptor 1, altering their original pharmacological and functional properties. Dimers can be not only constitutive, but perhaps also ligandpromoted: hence, compounds with high affinity for different ssts isoforms may be used to achieve effects elicited by specific dimers. Future developments in the knowledge of ssts dynamics upon SRIF and SRIF analogs binding in neoplastic tissues may allow the full elucidation of the pathophysiological role of this system and the exploitation of the therapeutic potential of its modulation.

  10. Biological de-activation of granular formulation of a carbamate insecticide Cartap in water under laboratory conditions

    Directory of Open Access Journals (Sweden)

    Khalid Abdullah


    Full Text Available Cartap 4% (Padan 4G™ at different concentrations was evaluated for its biological deactivation in laboratory-conditions. The insecticide at 1.88 ppm or above concentrations showed significant increase in percent of dead fingerlings up to 46 days insecticide aging as compared to the control, while 0.8 ppm and below proved to be sub-lethal concentrations. The LD50 at 0-day (fresh solution was 0.997 ppm, which gradually rose to 2.074 ppm up to the day 46. The chemical attained half-life in 44.89 days. Being a very slowly degrading insecticide, Cartap is not desirable in rice-fish culture and a threat to aquatic fauna.

  11. Mesoscopic biology

    Indian Academy of Sciences (India)

    G V Shivashankar


    In this paper we present a qualitative outlook of mesoscopic biology where the typical length scale is of the order of nanometers and the energy scales comparable to thermal energy. Novel biomolecular machines, governed by coded information at the level of DNA and proteins, operate at these length scales in biological systems. In recent years advances in technology have led to the study of some of the design principles of these machines; in particular at the level of an individual molecule. For example, the forces that operate in molecular interactions, the stochasticity involved in these interactions and their spatio-temporal dynamics are beginning to be explored. Understanding such design principles is opening new possibilities in mesoscopic physics with potential applications.

  12. Marine biology

    Energy Technology Data Exchange (ETDEWEB)

    Thurman, H.V.; Webber, H.H.


    This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the nature of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index.

  13. Biological Databases

    Directory of Open Access Journals (Sweden)

    Kaviena Baskaran


    Full Text Available Biology has entered a new era in distributing information based on database and this collection of database become primary in publishing information. This data publishing is done through Internet Gopher where information resources easy and affordable offered by powerful research tools. The more important thing now is the development of high quality and professionally operated electronic data publishing sites. To enhance the service and appropriate editorial and policies for electronic data publishing has been established and editors of article shoulder the responsibility.

  14. Biological biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Jorge-Herrero, E. [Servicio de Cirugia Experimental. Clinica Puerta de Hierro, Madrid (Spain)


    There are a number of situations in which substances of biological origin are employed as biomaterials. Most of them are macromolecules derived from isolated connective tissue or the connective tissue itself in membrane form, in both cases, the tissue can be used in its natural form or be chemically treated. In other cases, certain blood vessels can be chemically pretreated and used as vascular prostheses. Proteins such as albumin, collagen and fibrinogen are employed to coat vascular prostheses. Certain polysaccharides have also been tested for use in controlled drug release systems. Likewise, a number of tissues, such as dura mater, bovine pericardium, procine valves and human valves, are used in the preparation of cardiac prostheses. We also use veins from animals or humans in arterial replacement. In none of these cases are the tissues employed dissimilar to the native tissues as they have been chemically modified, becoming a new bio material with different physical and biochemical properties. In short, we find that natural products are being utilized as biomaterials and must be considered as such; thus, it is necessary to study both their chemicobiological and physicomechanical properties. In the present report, we review the current applications, problems and future prospects of some of these biological biomaterials. (Author) 84 refs.

  15. The ubiquitination of the influenza A virus PB1-F2 protein is crucial for its biological function.

    Directory of Open Access Journals (Sweden)

    Ivan Košík

    Full Text Available The aim of the present study was to identify what influences the short half-life of the influenza A virus PB1-F2 protein and whether a prolonged half-life affects the properties of this molecule. We hypothesized that the short half-life of PB1-F2 could conceal the phenotype of the protein. Because proteasome degradation might be involved in PB1-F2 degradation, we focused on ubiquitination, a common label for proteasome targeting. A cluster of lysine residues was demonstrated as an ubiquitination acceptor site in evolutionary and functionally distinct proteins. The PB1-F2 sequence alignment revealed a cluster of lysines on the carboxy terminal end of PB1-F2 in almost all of the GenBank sequences available to date. Using a proximity ligation assay, we identified ubiquitination as a novel posttranslational modification of PB1-F2. Changing the lysines at positions 73, 78, and 85 to arginines suppressed the ubiquitination of A/Puerto Rico/8/1934 (H1N1-derived PB1-F2. The mutation of the C-terminal lysine residue cluster positively affected the overall expression levels of avian A/Honk Kong/156/1997 (H5N1- and mammalian A/Puerto Rico/8/1934 (H1N1-derived PB1-F2. Moreover, increased PB1-F2 copy numbers strengthened the functions of this virus in the infected cells. The results of a minigenome luciferase reporter assay revealed an enhancement of viral RNA-dependent RNA polymerase activity in the presence of stabilized PB1-F2, regardless of viral origin. IFNβ antagonism was enhanced in 293T cells transfected with a plasmid expressing stabilized K→R mutant variants of PB1-F2. Compared with PB1-F2 wt, the loss of ubiquitination enhanced the antibody response after DNA vaccination. In summary, we revealed that PB1-F2 is an ubiquitinated IAV protein, and this posttranslational modification plays a central role in the regulation of the biological functions of this protein.


    Directory of Open Access Journals (Sweden)

    Abdel E. Ghaly


    Full Text Available Pesticides are chemical substances intended to protect food crops and livestock from pests in order to pro-mote agricultural productivity and protect public health. Contamination of soil, air and water and threat to human and animal health are the major constraints in the use of pesticides. Treatment of pesticide contaminated water is, therefore, paramount. Biological treatment provides the most economical option when compared to other treatment methods. The aim of the study was to develop a safe and effective in the farm biological treatment for low level agricultural pesticide wastewater. The degradation of the fungicide captan was evaluated under batch and continuous modes of operation with a retention time of 15 days. The initial cell number (30.1ח106 cells/mL in the soil water mixture first declined with time during the 24 h reaching 15.6ח106 and 11.1ח106 cells/mL in the batch and continuous bioreactors, respectively. This was due to the inhibitory effect of pesticide on some of the soil microbial species that had less tolerance to captan at the initial concentration of 144 mg L-1. Then, the microbial population started growing, reaching its maximum after 5 and 12 days from the start in the batch and continuous bioreactors, respectively. The lag period and the specific growth rate for the batch bioreactor were 22 h and 0.096 h-1, respectively. A captan degradation efficiency of 89.6% was achieved after 10 days in the continuous bioreactor compared to a degradation efficiency of 100% after 5 d in the batch bioreactor. This study showed that the effluent from the continuous bioreactor has a captan concentration of 12 mg L-1 which is not acceptable for livestock water according to Health Canada Guidelines. A half life of 52 h is observed in the batch bioreactor.

  17. Structural Biology Fact Sheet (United States)

    ... Home > Science Education > Structural Biology Fact Sheet Structural Biology Fact Sheet Tagline (Optional) Middle/Main Content Area What is structural biology? Structural biology is a field of science focused ...

  18. Simulating Biological and Non-Biological Motion (United States)

    Bruzzo, Angela; Gesierich, Benno; Wohlschlager, Andreas


    It is widely accepted that the brain processes biological and non-biological movements in distinct neural circuits. Biological motion, in contrast to non-biological motion, refers to active movements of living beings. Aim of our experiment was to investigate the mechanisms underlying mental simulation of these two movement types. Subjects had to…

  19. A Brief Introduction to Chinese Biological Biological

    Institute of Scientific and Technical Information of China (English)


    Chinese Biological Abstracts sponsored by the Library, the Shanghai Institutes for Biological Sciences, the Biological Documentation and Information Network, all of the Chinese Academy of Sciences, commenced publication in 1987 and was initiated to provide access to the Chinese information in the field of biology.

  20. Biological evaluation of 2'-[{sup 18}F]fluoroflumazenil ([{sup 18}F]FFMZ), a potential GABA receptor ligand for PET

    Energy Technology Data Exchange (ETDEWEB)

    Mitterhauser, Markus E-mail:; Wadsak, Wolfgang; Wabnegger, Leila; Mien, Leonhard-Key; Toegel, Stefan; Langer, Oliver; Sieghart, Werner; Viernstein, Helmut; Kletter, Kurt; Dudczak, Robert


    [{sup 11}C]Flumazenil, a highly selective benzodiazepine antagonist is the most extensively used GABA{sub A} ligand for PET so far. To overcome half life disadvantages of {sup 11}C a [{sup 18}F]-labeled flumazenil derivative, 2'-[{sup 18}F]fluoroflumazenil (FFMZ) was developed and biologically evaluated with respect to the GABA{sub A} receptor. Organ with the highest uptake was the pituitary gland. Brain uptake was high and followed the order cortex>thalamus>cerebellum>rest brain. Fluoroflumazenil displaced [{sup 3}H]flumazenil binding from membrane GABA{sub A} receptors with an IC{sub 50}value (3.5 nM) comparable to that of Flumazenil (2.8 nM). The presented data confirm the potential of [{sup 18}F]FFMZ for PET imaging of the GABA-ergic system.

  1. Effects of interlinker sequences on the biological properties of bispecific single-chain antibodies

    Institute of Scientific and Technical Information of China (English)

    FANG Min; JIANG Xin; YANG Zhi; YIN Changcheng; LI Hua; ZHAO Rui; ZHANG Zhong; LIN Qing; HUANG Hualiang


    Single-chain bispecific antibody (scBsAb) is one of the promising genetic engineering antibody formats for clinical application. But the effects of interlinker sequences on the biological properties of bispecific single-chain antibodies have not been studied in detail. Three interlinker sequences were designed and synthesized, and denominated as Fc, HSA, 205C′, respectively. Universal vectors with these different interlinker sequences for scBsAb expression in E. coli were constructed. A model scBsAb based on a reshaped single-chain antibody (scFv) against human CD3 and a scFv directed against human ovarian carcinoma were generated and expressed in E. coli. The results of SDS-PAGE and Western blot showed that the different interlinker sequences did not affect the expression levelof scBsAb. However, as demonstrated by ELISA and pharmacokinetics studies performed in mice, scBsAbs with different interlinker sequences had difference in the antigen-binding activities and terminal half-life time (T1/2β) in vivo, the interlinker HSA could remarkably prolong the retention time of scBsAb in blood. These results indicated that the peptide sequence of interlinker could affect important biological properties of scBsAb, such as antigen-binding properties and stability in vivo. So, selection of an appropriate interlinker sequence is very important for scBsAb construction. Optimal interlinker can bring scBsAb biologicalproperties more suitable for clinical application.

  2. Ambient and biological monitoring of cokeoven workers: determinants of the internal dose of polycyclic aromatic hydrocarbons. (United States)

    Jongeneelen, F J; van Leeuwen, F E; Oosterink, S; Anzion, R B; van der Loop, F; Bos, R P; van Veen, H G


    Polycyclic aromatic hydrocarbons (PAH) were measured in the breathing zone air of 56 battery workers at two cokeovens during three consecutive days. The concentration of total PAH ranged up to 186 micrograms/m3. Preshift and end of shift urine samples were collected to determine 1-hydroxypyrene, a metabolite of pyrene. Control urine samples were available from 44 workers in the shipping yard of a hot rolling mill. The median values of 1-hydroxypyrene in urine of smoking and non-smoking controls were 0.51 and 0.17 mumol/mol creatinine, respectively. Concentrations of 1-hydroxypyrene up to 11.2 mumol/mol were found in the urine of the cokeoven workers. At the start of the three day working period after 32 hours off work, the 1-hydroxypyrene concentrations were four times higher and at the end of the working period 10 times higher compared with control concentrations. Excretion of 1-hydroxypyrene occurred with a half life of 6-35 hours. Both the ambient air monitoring data and the biological monitoring data showed that the topside workers were the heaviest exposed workers. The relation between air monitoring data and biological monitoring data was not strong. Multiple regression analysis was performed to identify determinants of the internal dose. The combination of exposure and smoking amplify each other and the use of a protective airstream helmet decreases the internal dose. An effect of alcohol consumption and the use of medication on the toxicokinetics of pyrene was not found.

  3. Cell biology perspectives in phage biology. (United States)

    Ansaldi, Mireille


    Cellular biology has long been restricted to large cellular organisms. However, as the resolution of microscopic methods increased, it became possible to study smaller cells, in particular bacterial cells. Bacteriophage biology is one aspect of bacterial cell biology that has recently gained insight from cell biology. Despite their small size, bacteriophages could be successfully labeled and their cycle studied in the host cells. This review aims to put together, although non-extensively, several cell biology studies that recently pushed the elucidation of key mechanisms in phage biology, such as the lysis-lysogeny decision in temperate phages or genome replication and transcription, one step further.

  4. Biological warfare agents. (United States)

    Pohanka, Miroslav; Kuca, Kamil


    Biological warfare agents are a group of pathogens and toxins of biological origin that can be potentially misused for military or criminal purposes. The present review attempts to summarize necessary knowledge about biological warfare agents. The historical aspects, examples of applications of these agents such as anthrax letters, biological weapons impact, a summary of biological warfare agents and epidemiology of infections are described. The last section tries to estimate future trends in research on biological warfare agents.

  5. Identification of the biologically active liquid chemistry induced by a nonthermal atmospheric pressure plasma jet. (United States)

    Wende, Kristian; Williams, Paul; Dalluge, Joe; Gaens, Wouter Van; Aboubakr, Hamada; Bischof, John; von Woedtke, Thomas; Goyal, Sagar M; Weltmann, Klaus-Dieter; Bogaerts, Annemie; Masur, Kai; Bruggeman, Peter J


    The mechanism of interaction of cold nonequilibrium plasma jets with mammalian cells in physiologic liquid is reported. The major biological active species produced by an argon RF plasma jet responsible for cell viability reduction are analyzed by experimental results obtained through physical, biological, and chemical diagnostics. This is complemented with chemical kinetics modeling of the plasma source to assess the dominant reactive gas phase species. Different plasma chemistries are obtained by changing the feed gas composition of the cold argon based RF plasma jet from argon, humidified argon (0.27%), to argon/oxygen (1%) and argon/air (1%) at constant power. A minimal consensus physiologic liquid was used, providing isotonic and isohydric conditions and nutrients but is devoid of scavengers or serum constituents. While argon and humidified argon plasma led to the creation of hydrogen peroxide dominated action on the mammalian cells, argon-oxygen and argon-air plasma created a very different biological action and was characterized by trace amounts of hydrogen peroxide only. In particular, for the argon-oxygen (1%), the authors observed a strong negative effect on mammalian cell proliferation and metabolism. This effect was distance dependent and showed a half life time of 30 min in a scavenger free physiologic buffer. Neither catalase and mannitol nor superoxide dismutase could rescue the cell proliferation rate. The strong distance dependency of the effect as well as the low water solubility rules out a major role for ozone and singlet oxygen but suggests a dominant role of atomic oxygen. Experimental results suggest that O reacts with chloride, yielding Cl2(-) or ClO(-). These chlorine species have a limited lifetime under physiologic conditions and therefore show a strong time dependent biological activity. The outcomes are compared with an argon MHz plasma jet (kinpen) to assess the differences between these (at least seemingly) similar plasma sources.

  6. Biological conversion system (United States)

    Scott, C.D.

    A system for bioconversion of organic material comprises a primary bioreactor column wherein a biological active agent (zymomonas mobilis) converts the organic material (sugar) to a product (alcohol), a rejuvenator column wherein the biological activity of said biological active agent is enhanced, and means for circulating said biological active agent between said primary bioreactor column and said rejuvenator column.

  7. Synthetic biology: insights into biological computation. (United States)

    Manzoni, Romilde; Urrios, Arturo; Velazquez-Garcia, Silvia; de Nadal, Eulàlia; Posas, Francesc


    Organisms have evolved a broad array of complex signaling mechanisms that allow them to survive in a wide range of environmental conditions. They are able to sense external inputs and produce an output response by computing the information. Synthetic biology attempts to rationally engineer biological systems in order to perform desired functions. Our increasing understanding of biological systems guides this rational design, while the huge background in electronics for building circuits defines the methodology. In this context, biocomputation is the branch of synthetic biology aimed at implementing artificial computational devices using engineered biological motifs as building blocks. Biocomputational devices are defined as biological systems that are able to integrate inputs and return outputs following pre-determined rules. Over the last decade the number of available synthetic engineered devices has increased exponentially; simple and complex circuits have been built in bacteria, yeast and mammalian cells. These devices can manage and store information, take decisions based on past and present inputs, and even convert a transient signal into a sustained response. The field is experiencing a fast growth and every day it is easier to implement more complex biological functions. This is mainly due to advances in in vitro DNA synthesis, new genome editing tools, novel molecular cloning techniques, continuously growing part libraries as well as other technological advances. This allows that digital computation can now be engineered and implemented in biological systems. Simple logic gates can be implemented and connected to perform novel desired functions or to better understand and redesign biological processes. Synthetic biological digital circuits could lead to new therapeutic approaches, as well as new and efficient ways to produce complex molecules such as antibiotics, bioplastics or biofuels. Biological computation not only provides possible biomedical and

  8. Translational environmental biology: cell biology informing conservation. (United States)

    Traylor-Knowles, Nikki; Palumbi, Stephen R


    Typically, findings from cell biology have been beneficial for preventing human disease. However, translational applications from cell biology can also be applied to conservation efforts, such as protecting coral reefs. Recent efforts to understand the cell biological mechanisms maintaining coral health such as innate immunity and acclimatization have prompted new developments in conservation. Similar to biomedicine, we urge that future efforts should focus on better frameworks for biomarker development to protect coral reefs.

  9. Computational Systems Chemical Biology


    Oprea, Tudor I.; Elebeoba E. May; Leitão, Andrei; Tropsha, Alexander


    There is a critical need for improving the level of chemistry awareness in systems biology. The data and information related to modulation of genes and proteins by small molecules continue to accumulate at the same time as simulation tools in systems biology and whole body physiologically-based pharmacokinetics (PBPK) continue to evolve. We called this emerging area at the interface between chemical biology and systems biology systems chemical biology, SCB (Oprea et al., 2007).

  10. Generation of biologically active multi-sialylated recombinant human EPOFc in plants.

    Directory of Open Access Journals (Sweden)

    Alexandra Castilho

    Full Text Available Hyperglycosylated proteins are more stable, show increased serum half-life and less sensitivity to proteolysis compared to non-sialylated forms. This applies particularly to recombinant human erythropoietin (rhEPO. Recent progress in N-glycoengineering of non-mammalian expression hosts resulted in in vivo protein sialylation at great homogeneity. However the synthesis of multi-sialylated N-glycans is so far restricted to mammalian cells. Here we used a plant based expression system to accomplish multi-antennary protein sialylation. A human erythropoietin fusion protein (EPOFc was transiently expressed in Nicotiana benthamiana ΔXTFT, a glycosylation mutant that lacks plant specific N-glycan residues. cDNA of the hormone was co-delivered into plants with the necessary genes for (i branching (ii β1,4-galactosylation as well as for the (iii synthesis, transport and transfer of sialic acid. This resulted in the production of recombinant EPOFc carrying bi- tri- and tetra-sialylated complex N-glycans. The formation of this highly complex oligosaccharide structure required the coordinated expression of 11 human proteins acting in different subcellular compartments at different stages of the glycosylation pathway. In vitro receptor binding assays demonstrate the generation of biologically active molecules. We demonstrate the in planta synthesis of one of the most complex mammalian glycoforms pointing to an outstanding high degree of tolerance to changes in the glycosylation pathway in plants.

  11. Effects of transforming growth interacting factor on biological behaviors of gastric carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Zhong-Liang Hu; Ji-Fang Wen; De-Sheng Xiao; Hui Zhen; Chun-Yan Fu


    AIM:Transforming growth interacting factor (TGIF) is an inhibitor of both transforming growth factor β (TGF-β) and retinoid signaling pathways. Moreover, the activation of MAPK pathway can prolong its half-life. However, its role in carcinogenesis is still unknown. Thus we attempted to investigate the effect of TGIF on biologic behaviors of gastric carcinoma cells.METHODS: Gastric carcinoma cell line, SGC-7901, was stably transfected with plasmid PcDNA3.1-TGIF. Western blotting and cell immunohistochemistry screening for the highly expressing clone of TGIF were employed. The growth of transfected cells was investigated by MTT and colonyformation assays, and apoptosis was measured by flow cytometry (FCM) and transmission electron microscopy.Tumorigenicity of the transfectant cells was also analyzed.RESULTS: TGIF had no effect on the proliferation, cell cycle and apoptosis of SGC-7901 cells, but cellular organelles of cells transfected with TGIF were richer than those of vector control or parental cells. Its clones were smaller than the control ones in plate efficiency, and its tumor tissues also had no obvious necrosis compared with the vector control or parental cells. Moreover, TGIF could resist TGF-β mediated growth inhibition.CONCLUSION: TGIF may induce differentiation of stomach neoplastic cells. In addition, TGIF can counteract the growth inhibition induced by TGF-β.

  12. Comparative Study of α Half-life of 210Po in Metal Environment at CIAE with a Reference Value

    Institute of Scientific and Technical Information of China (English)

    ZHAO; Qing-zhang; HE; Ming; DONG; Ke-jun; WANG; Xiao-ming; WANG; Wei; RUAN; Xiang-dong; SHEN; Hong-tao; ZHANG; Hui; DOU; Liang; YANG; Xu-ran; XU; Yong-ning; PANG; Yi-jun; WU; Shao-yong; JIANG; Shan


    The influence of the electron screening on nuclear processes is studied by many scientists.Within the framework of the Gamow theory,a conventional expression for theαdecay probability is essentially given by the product of two factors:the cluster pre-formation and the penetration probabilities.The former may not affected by the electron screening.The second factor may

  13. Fission properties of einsteinium and fermium. [Half-life, kinetic energy release, mass division, prompt neutron emission

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, D.C.


    The systematics of the low energy fission of the fermium isotopes is studied considering half-lives, masss division, kinetic-energy release, and accompanying prompt neutron emission. It is shown that the low energy fission of the fermium isotopes is a microcosm of the fission process, exhibiting a wide range of half lives, mass and kinetic energy distributions and varying neutron emission. The trends in the fermium isotopes are considered. 23 references. (JFP)

  14. Experimental implementation and proof of principle for a radionuclidic purity test solely based on half-life measurement

    DEFF Research Database (Denmark)

    Jørgensen, Thomas; Jensen, Mikael


    have developed an GUI application for use as an easy and automated test tool in the production procedure.The test results show that this method fully complies with the requirements in the European Pharmacopoeia (Eur. Ph.) for RNP of FDG and F-18 Sodium Fluoride. (C) 2015 Elsevier Ltd. All rights...... reserved....

  15. In silico prediction of brain exposure: drug free fraction, unbound brain to plasma concentration ratio and equilibrium half-life (United States)

    Spreafico, Morena; Jacobson, Matthew P.


    The focus of CNS drug pharmacokinetics programs has recently shifted from determining the total concentrations in brain and blood to considering also unbound fractions and concentrations. Unfortunately, assessing unbound brain exposure experimentally requires demanding in vivo and in vitro studies. We propose a physical model, based on lipid binding and pH partitioning, to predict in silico the unbound volume of distribution in the brain. The model takes into account the partition of a drug into lipids, interstitial fluid and intracellular compartments of the brain. The results are in good agreement with the experimental data, suggesting that the contributions of lipid binding and pH partitioning are important in determining drug exposure in brain. The predicted values are used, together with predictions for plasma protein binding, as corrective terms in a second model to derive the unbound brain to plasma concentration ratio starting from experimental values of total concentration ratio. The calculated values of brain free fraction and passive permeability are also used to qualitatively determine the brain to plasma equilibration time in a model that shows promising results but is limited to a very small set of compounds. The models we propose are a step forward in understanding and predicting pharmacologically relevant exposure in brain starting from compounds’ chemical structure and neuropharmacokinetics, by using experimental total brain to plasma ratios, in silico calculated properties and simple physics-based approaches. The models can be used in central nervous system drug discovery programs for a fast and cheap assessment of unbound brain exposure. For existing compounds, the unbound ratios can be derived from experimental values of total brain to plasma ratios. For both existing and hypothetical compounds, the unbound volume of distribution due to lipid binding and pH partitioning can be calculated starting only from the chemical structure. PMID:23578025

  16. The functional half-life of an mRNA depends on the ribosome spacing in an early coding region

    DEFF Research Database (Denmark)

    Pedersen, Margit; Nissen, Søren; Mitarai, Namiko;


    Bacterial mRNAs are translated by closely spaced ribosomes and degraded from the 5'-end, with half-lives of around 2 min at 37 °C in most cases. Ribosome-free or "naked" mRNA is known to be readily degraded, but the initial event that inactivates the mRNA functionally has not been fully described...

  17. Sensitivity Analysis on the Half-Life of Trichloroethylene and the Distribution Coefficient at the Paducah Gaseous Diffusion Plant

    Energy Technology Data Exchange (ETDEWEB)

    Kopp, Joshua D [Univ of KY, Dept of Civil Engineering


    To determine the future extent of the TCE contamination plume at PGDP, a groundwater and solute transport model has been developed by the Department of Energy (DOE). The model used to perform these calculations is MODFLOWT which is an enhanced groundwater transport model developed by the United States Geological Survey (USGS). MODFLOWT models groundwater movement as well as the transport of species that are subject to adsorption and decay by using a finite difference method (Duffield et al 2001). A significant limitation of MODFLOWT is that it requires large amounts of data. This data can be difficult and expensive to obtain. MODFLOWT also requires excessive computational time to perform one simulation. It is desirable to have a model that can predict the spatial extent of the contaminant plume without as much required data and that does not require excessive computational times. The purpose of this study is to develop and alternative model to MODFLOWT that can produce similar results for possible use in a companion management model. The alternative model used in this study is an artificial neural network (ANN).

  18. Resetting Biological Clocks (United States)

    Winfree, Arthur T.


    Reports on experiments conducted on two biological clocks, in organisms in the plant and animal kingdoms, which indicate that biological oscillation can be arrested by a single stimulus of a definite strength delivered at the proper time. (GS)

  19. Biology is simple. (United States)

    Newman, Tim


    This paper explores the potential for simplicity to reveal new biological understanding. Borrowing selectively from physics thinking, and contrasting with Crick's reductionist philosophy, the author argues that greater emphasis on simplicity is necessary to advance biology and its applications.

  20. Biology of Blood (United States)

    ... here for the Professional Version Home Blood Disorders Biology of Blood Overview of Blood Resources In This ... Version. DOCTORS: Click here for the Professional Version Biology of Blood Overview of Blood Components of Blood ...

  1. Designing synthetic biology. (United States)

    Agapakis, Christina M


    Synthetic biology is frequently defined as the application of engineering design principles to biology. Such principles are intended to streamline the practice of biological engineering, to shorten the time required to design, build, and test synthetic gene networks. This streamlining of iterative design cycles can facilitate the future construction of biological systems for a range of applications in the production of fuels, foods, materials, and medicines. The promise of these potential applications as well as the emphasis on design has prompted critical reflection on synthetic biology from design theorists and practicing designers from many fields, who can bring valuable perspectives to the discipline. While interdisciplinary connections between biologists and engineers have built synthetic biology via the science and the technology of biology, interdisciplinary collaboration with artists, designers, and social theorists can provide insight on the connections between technology and society. Such collaborations can open up new avenues and new principles for research and design, as well as shed new light on the challenging context-dependence-both biological and social-that face living technologies at many scales. This review is inspired by the session titled "Design and Synthetic Biology: Connecting People and Technology" at Synthetic Biology 6.0 and covers a range of literature on design practice in synthetic biology and beyond. Critical engagement with how design is used to shape the discipline opens up new possibilities for how we might design the future of synthetic biology.




  3. Biology Myth-Killers (United States)

    Lampert, Evan


    "Biology Myth-Killers" is an activity designed to identify and correct common misconceptions for high school and college introductory biology courses. Students identify common myths, which double as biology misconceptions, and use appropriate sources to share the "truth" about the myths. This learner-centered activity is a fun…

  4. Computational systems chemical biology. (United States)

    Oprea, Tudor I; May, Elebeoba E; Leitão, Andrei; Tropsha, Alexander


    There is a critical need for improving the level of chemistry awareness in systems biology. The data and information related to modulation of genes and proteins by small molecules continue to accumulate at the same time as simulation tools in systems biology and whole body physiologically based pharmacokinetics (PBPK) continue to evolve. We called this emerging area at the interface between chemical biology and systems biology systems chemical biology (SCB) (Nat Chem Biol 3: 447-450, 2007).The overarching goal of computational SCB is to develop tools for integrated chemical-biological data acquisition, filtering and processing, by taking into account relevant information related to interactions between proteins and small molecules, possible metabolic transformations of small molecules, as well as associated information related to genes, networks, small molecules, and, where applicable, mutants and variants of those proteins. There is yet an unmet need to develop an integrated in silico pharmacology/systems biology continuum that embeds drug-target-clinical outcome (DTCO) triplets, a capability that is vital to the future of chemical biology, pharmacology, and systems biology. Through the development of the SCB approach, scientists will be able to start addressing, in an integrated simulation environment, questions that make the best use of our ever-growing chemical and biological data repositories at the system-wide level. This chapter reviews some of the major research concepts and describes key components that constitute the emerging area of computational systems chemical biology.

  5. Quantum biological information theory

    CERN Document Server

    Djordjevic, Ivan B


    This book is a self-contained, tutorial-based introduction to quantum information theory and quantum biology. It serves as a single-source reference to the topic for researchers in bioengineering, communications engineering, electrical engineering, applied mathematics, biology, computer science, and physics. The book provides all the essential principles of the quantum biological information theory required to describe the quantum information transfer from DNA to proteins, the sources of genetic noise and genetic errors as well as their effects. Integrates quantum information and quantum biology concepts; Assumes only knowledge of basic concepts of vector algebra at undergraduate level; Provides a thorough introduction to basic concepts of quantum information processing, quantum information theory, and quantum biology; Includes in-depth discussion of the quantum biological channel modelling, quantum biological channel capacity calculation, quantum models of aging, quantum models of evolution, quantum models o...

  6. Standard biological parts knowledgebase. (United States)

    Galdzicki, Michal; Rodriguez, Cesar; Chandran, Deepak; Sauro, Herbert M; Gennari, John H


    We have created the Knowledgebase of Standard Biological Parts (SBPkb) as a publically accessible Semantic Web resource for synthetic biology ( The SBPkb allows researchers to query and retrieve standard biological parts for research and use in synthetic biology. Its initial version includes all of the information about parts stored in the Registry of Standard Biological Parts ( SBPkb transforms this information so that it is computable, using our semantic framework for synthetic biology parts. This framework, known as SBOL-semantic, was built as part of the Synthetic Biology Open Language (SBOL), a project of the Synthetic Biology Data Exchange Group. SBOL-semantic represents commonly used synthetic biology entities, and its purpose is to improve the distribution and exchange of descriptions of biological parts. In this paper, we describe the data, our methods for transformation to SBPkb, and finally, we demonstrate the value of our knowledgebase with a set of sample queries. We use RDF technology and SPARQL queries to retrieve candidate "promoter" parts that are known to be both negatively and positively regulated. This method provides new web based data access to perform searches for parts that are not currently possible.

  7. Standard biological parts knowledgebase.

    Directory of Open Access Journals (Sweden)

    Michal Galdzicki

    Full Text Available We have created the Knowledgebase of Standard Biological Parts (SBPkb as a publically accessible Semantic Web resource for synthetic biology ( The SBPkb allows researchers to query and retrieve standard biological parts for research and use in synthetic biology. Its initial version includes all of the information about parts stored in the Registry of Standard Biological Parts ( SBPkb transforms this information so that it is computable, using our semantic framework for synthetic biology parts. This framework, known as SBOL-semantic, was built as part of the Synthetic Biology Open Language (SBOL, a project of the Synthetic Biology Data Exchange Group. SBOL-semantic represents commonly used synthetic biology entities, and its purpose is to improve the distribution and exchange of descriptions of biological parts. In this paper, we describe the data, our methods for transformation to SBPkb, and finally, we demonstrate the value of our knowledgebase with a set of sample queries. We use RDF technology and SPARQL queries to retrieve candidate "promoter" parts that are known to be both negatively and positively regulated. This method provides new web based data access to perform searches for parts that are not currently possible.

  8. Evaluation of flow injection analysis for determination of cholinesterase activities in biological material. (United States)

    Cabal, Jiri; Bajgar, Jiri; Kassa, Jiri


    The method for automatic continual monitoring of acetylcholinesterase (AChE) activity in biological material is described. It is based on flexible system of plastic pipes mixing samples of biological material with reagents for enzyme determination; reaction product penetrates through the semipermeable membrane and it is spectrophotometrically determined (Ellman's method). It consists of sampling (either in vitro or in vivo), adding the substrate and flowing to dialyzer; reaction product (thiocholine) is dialyzed and mixed with 5,5'-dithio-bis-2-nitrobenzoic acid (DTNB) transported to flow spectrophotometer. Flowing of all materials is realised using peristaltic pump. The method was validated: time for optimal hydratation of the cellophane membrane; type of the membrane; type of dialyzer; conditions for optimal permeation of reaction components; optimization of substrate and DTNB concentrations (linear dependence); efficacy of peristaltic pump; calibration of analytes after permeation through the membrane; excluding of the blood permeation through the membrane. Some examples of the evaluation of the effects of AChE inhibitors are described. It was demonstrated very good uniformity of peaks representing the enzyme activity (good reproducibility); time dependence of AChE inhibition caused by VX in vitro in the rat blood allowing to determine the half life of inhibition and thus, bimolecular rate constants of inhibition; reactivation of inhibited AChE by some reactivators, and continual monitoring of the activity in the whole blood in vivo in intact and VX-intoxicated rats. The method is simple and not expensive, allowing automatic determination of AChE activity in discrete or continual samples in vitro or in vivo. It will be evaluated for further research of cholinesterase inhibitors.

  9. Plant synthetic biology. (United States)

    Liu, Wusheng; Stewart, C Neal


    Plant synthetic biology is an emerging field that combines engineering principles with plant biology toward the design and production of new devices. This emerging field should play an important role in future agriculture for traditional crop improvement, but also in enabling novel bioproduction in plants. In this review we discuss the design cycles of synthetic biology as well as key engineering principles, genetic parts, and computational tools that can be utilized in plant synthetic biology. Some pioneering examples are offered as a demonstration of how synthetic biology can be used to modify plants for specific purposes. These include synthetic sensors, synthetic metabolic pathways, and synthetic genomes. We also speculate about the future of synthetic biology of plants.

  10. Branching processes in biology

    CERN Document Server

    Kimmel, Marek


    This book provides a theoretical background of branching processes and discusses their biological applications. Branching processes are a well-developed and powerful set of tools in the field of applied probability. The range of applications considered includes molecular biology, cellular biology, human evolution and medicine. The branching processes discussed include Galton-Watson, Markov, Bellman-Harris, Multitype, and General Processes. As an aid to understanding specific examples, two introductory chapters, and two glossaries are included that provide background material in mathematics and in biology. The book will be of interest to scientists who work in quantitative modeling of biological systems, particularly probabilists, mathematical biologists, biostatisticians, cell biologists, molecular biologists, and bioinformaticians. The authors are a mathematician and cell biologist who have collaborated for more than a decade in the field of branching processes in biology for this new edition. This second ex...

  11. Chemical Biology is.....



    Chemical Biology is a relatively new field, and as such is not yet simply or succinctly defined. It includes such a wide range of fundamental problems that this commentary could only include just a few snapshots of potential areas of interest. Overarching themes and selected recent successes and ideas in chemical biology are described to illustrate broadly the scope of the field, but should not be taken as exhaustive. The Chemical Biology Section of Chemistry Central Journal is pleased to rec...

  12. Biological detector and method

    Energy Technology Data Exchange (ETDEWEB)

    Sillerud, Laurel; Alam, Todd M.; McDowell, Andrew F.


    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  13. Biological detector and method (United States)

    Sillerud, Laurel; Alam, Todd M; McDowell, Andrew F


    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  14. Biological Individuality of Man (United States)


    RECIPIENT’S CAT * LOO NUMBER Biological Individuality of Man 5 TlrPE OF REPORT a PERIOD COVERED Technical « PERFORMING ORO REPORT...Variability 13 A. Background , 13 B. Slatistictl Approaches to Biological Variability 13 C. Genetic Aspects of Biological Variability . 14 III...ioiological determinants of individuality. Only recently, have genetic infaienccs been investigated and the potentialities for future control of bio

  15. Biological detector and method (United States)

    Sillerud, Laurel; Alam, Todd M; McDowell, Andrew F


    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  16. [Preparation and the biological effect of fusion protein GLP-1-exendin-4/ IgG4(Fc) fusion protein as long acting GLP-1 receptor agonist]. (United States)

    Zheng, Yun-cheng


    GLP-1 has a variety of anti-diabetic effects. However, native GLP-1 is not suitable for treatment of diabetes due to its short half-life (t½, 2-5 min). Exendin-4 is a polypeptide isolated from lizard saliva, which can bind to GLP-1 receptor, produce physiological effects similar to GLP-1, t½ up to 2.5 h, therefore, we developed a long-lasting GLP-1 receptor agonists and GLP-1-exendin-4 fusion IgG4 Fc [GLP-1-exendin-4/ IgG4(Fc)]. We constructed the eukaryotic expression vector of human GLP-1-exendin-4/IgG4(Fc)-pOptiVEC- TOPO by gene recombination technique and expressed the fusion protein human GLP-1-IgG4 (Fc) in CHO/DG44 cells. The fusion protein stimulated the INS-1 cells secretion of insulin, GLP-1, exendin-4 and fusion protein in CD1 mice pharmacokinetic experiments, as well as GLP-1, exendin-4 and fusion protein did anti-diabetic effect on streptozotocin induced mice. Results demonstrated that the GLP-1-exendin-4/IgG4(Fc) positive CHO/DG44 clones were chosen and the media from these positive clones. Western blotting showed that one protein band was found to match well with the predicted relative molecular mass of human GLP-1-exendin-4/IgG4(Fc). Insulin RIA showed that GLP-1-exendin-4/IgG4(Fc) dose-dependently stimulated insulin secretion from INS-1 cells. Pharmacokinetic studies in CD1 mice showed that with intraperitoneal injection (ip), the fusion protein peaked at 30 min in circulation and maintained a plateau for 200 h. Natural biological half-life of exendin-4 was (1.39 ± 0.28) h, GLP-1 in vivo t½ 4 min, indicating that fusion protein has long-lasting effects on the modulation of glucose homeostasis. GLP-1-exendin-4/IgG4(Fc) was found to be effective in reducing the incidence of diabetes in multiple-low-dose streptozotocin-induced diabetes in mice, longer duration of the biological activity of the fusion protein. The biological activity was significantly higher than that of GLP-1 and exendin-4. GLP-1-exendin-4/IgG4(Fc) has good anti-diabetic activity

  17. Chemical space and biology. (United States)

    Dobson, Christopher M


    Chemical space--which encompasses all possible small organic molecules, including those present in biological systems--is vast. So vast, in fact, that so far only a tiny fraction of it has been explored. Nevertheless, these explorations have greatly enhanced our understanding of biology, and have led to the development of many of today's drugs. The discovery of new bioactive molecules, facilitated by a deeper understanding of the nature of the regions of chemical space that are relevant to biology, will advance our knowledge of biological processes and lead to new strategies to treat disease.

  18. Polythiophenes in biological applications. (United States)

    Sista, Prakash; Ghosh, Koushik; Martinez, Jennifer S; Rocha, Reginaldo C


    Polythiophene and its derivatives have shown tremendous potential for interfacing electrically conducting polymers with biological applications. These semiconducting organic polymers are relatively soft, conduct electrons and ions, have low cytotoxicity, and can undergo facile chemical modifications. In addition, the reduction in electrical impedance of electrodes coated with polythiophenes may prove to be invaluable for a stable and permanent connection between devices and biological tissues. This review article focuses on the synthesis and some key applications of polythiophenes in multidisciplinary areas at the interface with biology. These polymers have shown tremendous potential in biological applications such as diagnostics, therapy, drug delivery, imaging, implant devices and artificial organs.

  19. Biology Library Workbook. (United States)

    Miller, Constance; And Others

    A library skills workbook provides college biology students with an introduction to biological library resources. Divided into two sections, the first contains explanations of the various steps in the library research process. The second consists of exercises keyed to the explanatory chapters of the first section. (RAA)

  20. Homosexuality, biology, and ideology. (United States)

    Haumann, G


    This paper critically examines the complex relationships and interdependencies between biological theories on homosexuality and sociosexual ideologies. It challenges the privileged status of biology as the ultimate authority on homosexuality. This status is based on the belief that biology is a value-free science. On the contrary, this essay shows how unacknowledged assumptions and culturally bound patterns of thinking about sexuality taint biological research. Sociosexual ideologies are defined as principles that organize the ways we express our sexualities and the way we theorize about them in biology. The following ideologies are identified: (1) sexuality-as-heterosexuality, (2) sexuality-as-reproduction, (3) sexual dualism (male vs. female), and (4) the view the homosexuality is a sexual inversion. The process by which these ideologies are incorporated into biology is two-fold: (1) as a projective act from society onto nature and (2) as a reflective act from nature back into society. It is further argued that biological knowledge of homosexuality resulting from that process can be used for diverse political interests. Finally, it is proposed that since biological theories on homosexuality are inseparable from the context of their paradigmatic origin, it is possible that new theories could be derived from new ideologies.

  1. Psoriasis : implications of biologics

    NARCIS (Netherlands)

    Lecluse, L.L.A.


    Since the end of 2004 several specific immunomodulating therapies: ‘biologic response modifiers’ or ‘biologics’ have been registered for moderate to severe psoriasis in Europe. This thesis is considering the implications of the introduction of the biologics for psoriasis patients, focusing on safety

  2. Biological Macromolecule Crystallization Database (United States)

    SRD 21 Biological Macromolecule Crystallization Database (Web, free access)   The Biological Macromolecule Crystallization Database and NASA Archive for Protein Crystal Growth Data (BMCD) contains the conditions reported for the crystallization of proteins and nucleic acids used in X-ray structure determinations and archives the results of microgravity macromolecule crystallization studies.

  3. Experimenting with Mathematical Biology (United States)

    Sanft, Rebecca; Walter, Anne


    St. Olaf College recently added a Mathematical Biology concentration to its curriculum. The core course, Mathematics of Biology, was redesigned to include a wet laboratory. The lab classes required students to collect data and implement the essential modeling techniques of formulation, implementation, validation, and analysis. The four labs…

  4. Introduction to systems biology

    NARCIS (Netherlands)

    Bruggeman, F.J.; Hornberg, J.J.; Boogerd, F.C.; Westerhoff, H.V.; Boogerd, F.C.; Bruggeman, F.J.; Hofmeyr, J.H.S.; Westerhoff, H.V.


    The developments in the molecular biosciences have made possible a shift to combined molecular and system-level approaches to biological research under the name of Systems Biology. It integrates many types of molecular knowledge, which can best be achieved by the synergistic use of models and experi

  5. Michaelis-Menten elimination kinetics of etanercept, rheumatoid arthritis biologics, after intravenous and subcutaneous administration in rats. (United States)

    Lee, Byung-Yo; Kwon, Kwang-Il; Kim, Min-Soo; Baek, In-Hwan


    Etanercept was approved by the Food and Drug Administration (FDA) in 2010 as a biologic agent for the treatment of rheumatoid arthritis (RA). The aim of the study was to investigate the pharmacokinetic properties of etanercept after intravenous and subcutaneous injection in rats. The plasma concentration of etanercept was determined using an enzyme-linked immunosorbent assay (ELISA). Intravenous and subcutaneous administration of 2 mg/kg of etanercept to rats showed that etanercept was slowly absorbed (time to reach the peak drug concentration [T max] = 1.60 days, bioavailability [F] = 47.18 %) and slowly eliminated (half-life [t 1/2], 2.33 days after intravenous administration and 3.31 days after subcutaneous administration). The area under the curve values on day 13 (AUC13day) were 121.25 ± 14.37 and 48.56 ± 6.78 μg day/mL after intravenous and subcutaneous administration, respectively. A two-compartment model with Michaelis-Menten elimination kinetics (V max = 94.28 µg/day; K m = 10.88 µg/mL) was used to describe the pharmacokinetic profile of etanercept. Our results describe the pharmacokinetic profile of etanercept, and these results could be used for the development of etanercept biosimilars.

  6. Kinetics and mechanism of superoxide radical reactions with some biologically important compounds in aqueous solutions. Pulse radiolysis (United States)

    Revina, A. A.; Amiragova, M. I.; Volod'ko, V. V.; Vannikov, A. V.

    Microsecond pulse radiolysis of oxygenated aqueous solutions containing 0.02 mol dm -3 sodium formate and 2 mmol dm -3 phosphate buffer at pH 7 was used to generate superoxide anion radicals. The influence of some biologically important compounds upon the rate of O ⨪2 decay was monitored spectrophotometrically in the range of 245-300 nm. Hematoporphyrin (HP), hemin C (HC), catalase (Cat), cobalt sulfophthalocyanine (CoTSPc) were studied. Among the investigated compounds only Cat was found to show a high catalytic efficiency towards the self-decay of O ⨪2. A red shift of O ⨪2 absorption band and slowing down of its decay were observed to take place by adding HP or CoTSPc to the solutions containing formate ions in excess. This effect is associated with the formation of a transient superoxo-complex. An appearance of an intermediate species with absorption maxima at 350 nm and half-life of about 2s was observed to accompany the superoxo-complex of CoTSPc decay. In the aerated solution of HP the intensity of absorbance at 260 nm was found to be independent of the presence of formate ions.

  7. Frontiers in mathematical biology

    CERN Document Server


    Volume 100, which is the final volume of the LNBM series serves to commemorate the acievements in two decades of this influential collection of books in mathematical biology. The contributions, by the leading mathematical biologists, survey the state of the art in the subject, and offer speculative, philosophical and critical analyses of the key issues confronting the field. The papers address fundamental issues in cell and molecular biology, organismal biology, evolutionary biology, population ecology, community and ecosystem ecology, and applied biology, plus the explicit and implicit mathematical challenges. Cross-cuttting issues involve the problem of variation among units in nonlinear systems, and the related problems of the interactions among phenomena across scales of space, time and organizational complexity.

  8. Space biology research development (United States)

    Bonting, Sjoerd L.


    The purpose of the Search for Extraterrestrial Intelligence (SETI) Institute is to conduct and promote research related activities regarding the search for extraterrestrial life, particularly intelligent life. Such research encompasses the broad discipline of 'Life in the Universe', including all scientific and technological aspects of astronomy and the planetary sciences, chemical evolution, the origin of life, biological evolution, and cultural evolution. The primary purpose was to provide funding for the Principal Investigator to collaborate with the personnel of the SETI Institute and the NASA-Ames Research center in order to plan and develop space biology research on and in connection with Space Station Freedom; to promote cooperation with the international partners in the space station; to conduct a study on the use of biosensors in space biology research and life support system operation; and to promote space biology research through the initiation of an annual publication 'Advances in Space Biology and Medicine'.

  9. Optics of Biological Particles

    CERN Document Server

    Hoekstra, Alfons; Videen, Gorden


    This book covers the optics of single biological particles, both theory and experiment, with emphasis on Elastic Light Scattering and Fluorescence. It deals with the optics of bacteria (bio-aerosols), marine particles (selected phytoplankton communities) and red and white blood cells. Moreover, there are dedicated chapters on a general theory for scattering by a cell, and modelling and simulation of scattering by inhomogeneous biological cells. Finally, one chapter is dedicated to astro-biological signatures, discussing the possibilities for detecting non-terrestrial biological material. The volume has up-to-date discussions on new experimental and numerical techniques, and many examples of applications of these techniques in real-life systems, as used to detect and characterize e.g. biological warfare agents or human blood cells.

  10. Biological sample collector (United States)

    Murphy, Gloria A.


    A biological sample collector is adapted to a collect several biological samples in a plurality of filter wells. A biological sample collector may comprise a manifold plate for mounting a filter plate thereon, the filter plate having a plurality of filter wells therein; a hollow slider for engaging and positioning a tube that slides therethrough; and a slide case within which the hollow slider travels to allow the tube to be aligned with a selected filter well of the plurality of filter wells, wherein when the tube is aligned with the selected filter well, the tube is pushed through the hollow slider and into the selected filter well to sealingly engage the selected filter well and to allow the tube to deposit a biological sample onto a filter in the bottom of the selected filter well. The biological sample collector may be portable.

  11. Evaluation of the effectiveness and safety of the thermo-treatment process to dispose of recombinant DNA waste from biological research laboratories. (United States)

    Li, Meng-Nan; Zheng, Guang-Hong; Wang, Lei; Xiao, Wei; Fu, Xiao-Hua; Le, Yi-Quan; Ren, Da-Ming


    The discharge of recombinant DNA waste from biological laboratories into the eco-system may be one of the pathways resulting in horizontal gene transfer or "gene pollution". Heating at 100 degrees C for 5-10 min is a common method for treating recombinant DNA waste in biological research laboratories in China. In this study, we evaluated the effectiveness and the safety of the thermo-treatment method in the disposal of recombinant DNA waste. Quantitative PCR, plasmid transformation and electrophoresis technology were used to evaluate the decay/denaturation efficiency during the thermo-treatment process of recombinant plasmid, pET-28b. Results showed that prolonging thermo-treatment time could improve decay efficiency of the plasmid, and its decay half-life was 2.7-4.0 min during the thermo-treatment at 100 degrees C. However, after 30 min of thermo-treatment some transforming activity remained. Higher ionic strength could protect recombinant plasmid from decay during the treatment process. These results indicate that thermo-treatment at 100 degrees C cannot decay and inactivate pET-28b completely. In addition, preliminary results showed that thermo-treated recombinant plasmids were not degraded completely in a short period when they were discharged into an aquatic environment. This implies that when thermo-treated recombinant DNAs are discharged into the eco-system, they may have enough time to re-nature and transform, thus resulting in gene diffusion.

  12. Managing biological diversity (United States)

    Samson, Fred B.; Knopf, Fritz L.


    Biological diversity is the variety of life and accompanying ecological processes (Off. Technol. Assess. 1987, Wilcove and Samson 1987, Keystone 1991). Conservation of biological diversity is a major environmental issue (Wilson 1988, Counc. Environ. Quality 1991). The health and future of the earth's ecological systems (Lubchenco et al. 1991), global climate change (Botkin 1990), and an ever-increasing rate in loss of species, communities, and ecological systems (Myers 1990) are among issues drawing biological diversity to the mainstream of conservation worldwide (Int. Union Conserv. Nat. and Nat. Resour. [IUCN] et al. 1991). The legal mandate for conserving biological diversity is now in place (Carlson 1988, Doremus 1991). More than 19 federal laws govern the use of biological resources in the United States (Rein 1991). The proposed National Biological Diversity Conservation and Environmental Research Act (H.R. 585 and S.58) notes the need for a national biological diversity policy, would create a national center for biological diversity research, and recommends a federal interagency strategy for ecosystem conservation. There are, however, hard choices ahead for the conservation of biological diversity, and biologists are grappling with how to set priorities in research and management (Roberts 1988). We sense disillusion among field biologists and managers relative to how to operationally approach the seemingly overwhelming charge of conserving biological diversity. Biologists also need to respond to critics like Hunt (1991) who suggest a tree farm has more biological diversity than an equal area of old-growth forest. At present, science has played only a minor role in the conservation of biological diversity (Weston 1992) with no unified approach available to evaluate strategies and programs that address the quality and quantity of biological diversity (Murphy 1990, Erwin 1992). Although actions to conserve biological diversity need to be clearly defined by

  13. Molecular self-assembly for biological investigations and nanoscale lithography (United States)

    Cheunkar, Sarawut

    Small, diffusible molecules when recognized by their binding partners, such as proteins and antibodies, trigger enzymatic activity, cell communication, and immune response. Progress in analytical methods enabling detection, characterization, and visualization of biological dynamics at the molecular level will advance our exploration of complex biological systems. In this dissertation, analytical platforms were fabricated to capture membrane-associated receptors, which are essential proteins in cell signaling pathways. The neurotransmitter serotonin and its biological precursor were immobilized on gold substrates coated with self-assembled monolayers (SAMs) of oligo(ethylene glycol)alkanethiols and their reactive derivatives. The SAM-coated substrates present the biologically selective affinity of immobilized molecules to target native membrane-associated receptors. These substrates were also tested for biospecificity using antibodies. In addition, small-molecule-functionalized platforms, expressing neurotransmitter pharmacophores, were employed to examine kinetic interactions between G-protein-coupled receptors and their associated neurotransmitters. The binding interactions were monitored using a quartz crystal microbalance equipped with liquid-flow injection. The interaction kinetics of G-protein-coupled serotonin 1A receptor and 5-hydroxytyptophan-functionalized surfaces were studied in a real-time, label-free environment. Key binding parameters, such as equilibrium dissociation constants, binding rate constants, and dissociative half-life, were extracted. These parameters are critical for understanding and comparing biomolecular interactions in modern biomedical research. By integrating self-assembly, surface functionalization, and nanofabrication, small-molecule microarrays were created for high-throughput screening. A hybrid soft-lithography, called microcontact insertion printing, was used to pattern small molecules at the dilute scales necessary for highly

  14. Biological and Chemical Security

    Energy Technology Data Exchange (ETDEWEB)

    Fitch, P J


    The LLNL Chemical & Biological National Security Program (CBNP) provides science, technology and integrated systems for chemical and biological security. Our approach is to develop and field advanced strategies that dramatically improve the nation's capabilities to prevent, prepare for, detect, and respond to terrorist use of chemical or biological weapons. Recent events show the importance of civilian defense against terrorism. The 1995 nerve gas attack in Tokyo's subway served to catalyze and focus the early LLNL program on civilian counter terrorism. In the same year, LLNL began CBNP using Laboratory-Directed R&D investments and a focus on biodetection. The Nunn-Lugar-Domenici Defense Against Weapons of Mass Destruction Act, passed in 1996, initiated a number of U.S. nonproliferation and counter-terrorism programs including the DOE (now NNSA) Chemical and Biological Nonproliferation Program (also known as CBNP). In 2002, the Department of Homeland Security was formed. The NNSA CBNP and many of the LLNL CBNP activities are being transferred as the new Department becomes operational. LLNL has a long history in national security including nonproliferation of weapons of mass destruction. In biology, LLNL had a key role in starting and implementing the Human Genome Project and, more recently, the Microbial Genome Program. LLNL has over 1,000 scientists and engineers with relevant expertise in biology, chemistry, decontamination, instrumentation, microtechnologies, atmospheric modeling, and field experimentation. Over 150 LLNL scientists and engineers work full time on chemical and biological national security projects.

  15. Synthesis, Biological Evaluation, and Pharmacokinetic Study of Novel Liguzinediol Prodrugs

    Directory of Open Access Journals (Sweden)

    Long Chen


    Full Text Available Liguzinediol (LZDO ester prodrugs 3–5 were synthesized and evaluated in vitro and in vivo for their potential use in prolonging the half-life of the parent drug LZDO (1a in vivo. Prodrugs 3–5 were found to display a potent positive inotropic effect on the myocardium, without the risk of arrhythmia. Prodrugs 3–5 rapidly underwent enzymatic hydrolysis to release the parent compound LZDO in 1–3 h in rat liver microsomes and rat plasma. The half-life of the parent compound was prolonged after intragastric administration of prodrug 3, which was found to be a superior prodrug candidate for increasing myocardial contractility.

  16. Thermodynamics of Biological Processes (United States)

    Garcia, Hernan G.; Kondev, Jane; Orme, Nigel; Theriot, Julie A.; Phillips, Rob


    There is a long and rich tradition of using ideas from both equilibrium thermodynamics and its microscopic partner theory of equilibrium statistical mechanics. In this chapter, we provide some background on the origins of the seemingly unreasonable effectiveness of ideas from both thermodynamics and statistical mechanics in biology. After making a description of these foundational issues, we turn to a series of case studies primarily focused on binding that are intended to illustrate the broad biological reach of equilibrium thinking in biology. These case studies include ligand-gated ion channels, thermodynamic models of transcription, and recent applications to the problem of bacterial chemotaxis. As part of the description of these case studies, we explore a number of different uses of the famed Monod–Wyman–Changeux (MWC) model as a generic tool for providing a mathematical characterization of two-state systems. These case studies should provide a template for tailoring equilibrium ideas to other problems of biological interest. PMID:21333788

  17. Hammond Bay Biological Station (United States)

    Federal Laboratory Consortium — Hammond Bay Biological Station (HBBS), located near Millersburg, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). HBBS was established by...

  18. Enhanced Biological Sampling Data (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a database of a variety of biological, reproductive, and energetic data collected from fish on the continental shelf in the northwest Atlantic Ocean. Species...

  19. Chemistry and biology data (United States)

    U.S. Environmental Protection Agency — Chemical monitoring data and biological data from field collected samples. This dataset is associated with the following publication: Biales , A., D. Denton , D....

  20. Laboratory of Biological Modeling (United States)

    Federal Laboratory Consortium — The Laboratory of Biological Modeling is defined by both its methodologies and its areas of application. We use mathematical modeling in many forms and apply it to...

  1. Laboratory of Biological Modeling (United States)

    Federal Laboratory Consortium — The Laboratory of Biological Modeling is defined by both its methodologies and its areas of application. We use mathematical modeling in many forms and apply it to a...

  2. Precision Measurement in Biology (United States)

    Quake, Stephen

    Is biology a quantitative science like physics? I will discuss the role of precision measurement in both physics and biology, and argue that in fact both fields can be tied together by the use and consequences of precision measurement. The elementary quanta of biology are twofold: the macromolecule and the cell. Cells are the fundamental unit of life, and macromolecules are the fundamental elements of the cell. I will describe how precision measurements have been used to explore the basic properties of these quanta, and more generally how the quest for higher precision almost inevitably leads to the development of new technologies, which in turn catalyze further scientific discovery. In the 21st century, there are no remaining experimental barriers to biology becoming a truly quantitative and mathematical science.

  3. Biological satellite Kosmos-936 (United States)

    Vedeshin, L. A.


    A description is given of physiological experiments performed on the biological satellite Kosmos-936. Other experiments to determine the electrostatic and dielectric responses to the effects of cosmic radiation are discussed.

  4. Fishery Biology Database (AGDBS) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Basic biological data are the foundation on which all assessments of fisheries resources are built. These include parameters such as the size and age composition of...

  5. Large Pelagics Biological Survey (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Large Pelagics Biological Survey (LPBS) collects additional length and weight information and body parts such as otoliths, caudal vertebrae, dorsal spines, and...

  6. Vibrations, Quanta and Biology

    CERN Document Server

    Huelga, S F


    Quantum biology is an emerging field of research that concerns itself with the experimental and theoretical exploration of non-trivial quantum phenomena in biological systems. In this tutorial overview we aim to bring out fundamental assumptions and questions in the field, identify basic design principles and develop a key underlying theme -- the dynamics of quantum dynamical networks in the presence of an environment and the fruitful interplay that the two may enter. At the hand of three biological phenomena whose understanding is held to require quantum mechanical processes, namely excitation and charge transfer in photosynthetic complexes, magneto-reception in birds and the olfactory sense, we demonstrate that this underlying theme encompasses them all, thus suggesting its wider relevance as an archetypical framework for quantum biology.

  7. Mechanical Biological Treatment

    DEFF Research Database (Denmark)

    Bilitewski, B-; Oros, Christiane; Christensen, Thomas Højlund


    or residual waste (after some recyclables removed at the source). The concept was originally to reduce the amount of waste going to landfill, but MBT technologies are today also seen as plants recovering fuel as well as material fractions. As the name suggests the technology combines mechanical treatment......The basic processes and technologies of composting and anaerobic digestion, as described in the previous chapters, are usually used for specific or source-separated organic waste flows. However, in the 1990s mechanical biological waste treatment technologies (MBT) were developed for unsorted...... technologies (screens, sieves, magnets, etc.) with biological technologies (composting, anaerobic digestion). Two main technologies are available: Mechanical biological pretreatment (MBP), which first removes an RDF fraction and then biologically treats the remaining waste before most of it is landfilled...

  8. Multiscale Biological Materials

    DEFF Research Database (Denmark)

    Frølich, Simon

    example of biological design. We investigated the architecture of A. simplex and found that an advanced hierarchical biomineralized structure acts as the interface between soft musculature and a stiff substrate, thus securing underwater attachment. In bone, the mechanical properties of the material......, and the nanoscale response of bone in compression. Lastly, a framework for the investigation of biological design principles has been developed. The framework combines parametric modeling, multi-material 3D-printing, and direct mechanical testing to efficiently screen large parameter spaces of biological design. We......Materials formed by organisms, also known as biological materials, exhibit outstanding structural properties. The range of materials formed in nature is remarkable and their functions include support, protection, motion, sensing, storage, and maintenance of physiological homeostasis. These complex...

  9. [Systems biology of cancer]. (United States)

    Barillot, Emmanuel; Calzone, Laurence; Zinovyev, Andrei


    Cancer Systems Biology is now accepted and recognized as a promising field both in biological and clinical research. It relies on a rigorous formalization of regulation networks into precise and unambiguous languages. It provides both detailed and modular views of the complex biological system of interest (which in cancer research is typically an interaction network governing essential cellular events such as proliferation, differentiation, cell death...) in order to facilitate the interpretation of molecular profiles of tumors. The translation of these networks into mathematical models allows prediction of the evolution of the system in time and under certain perturbations. As a result, it can not only propose specific target points for pharmaceutical purposes, but also anticipate the evolution of tumors as well as their classifications. These characteristics emphasize the important role of Systems Biology of Cancer in the future of biomedical research.

  10. Insecticides and Biological Control (United States)

    Furness, G. O.


    Use of insecticides has been questioned due to their harmful effects on edible items. Biological control of insects along with other effective practices for checking spread of parasites on crops are discussed. (PS)

  11. Nestedness across biological scales (United States)

    Marquitti, Flavia M. D.; Raimundo, Rafael L. G.; Sebastián-González, Esther; Coltri, Patricia P.; Perez, S. Ivan; Brandt, Débora Y. C.; Nunes, Kelly; Daura-Jorge, Fábio G.; Floeter, Sergio R.; Guimarães, Paulo R.


    Biological networks pervade nature. They describe systems throughout all levels of biological organization, from molecules regulating metabolism to species interactions that shape ecosystem dynamics. The network thinking revealed recurrent organizational patterns in complex biological systems, such as the formation of semi-independent groups of connected elements (modularity) and non-random distributions of interactions among elements. Other structural patterns, such as nestedness, have been primarily assessed in ecological networks formed by two non-overlapping sets of elements; information on its occurrence on other levels of organization is lacking. Nestedness occurs when interactions of less connected elements form proper subsets of the interactions of more connected elements. Only recently these properties began to be appreciated in one-mode networks (where all elements can interact) which describe a much wider variety of biological phenomena. Here, we compute nestedness in a diverse collection of one-mode networked systems from six different levels of biological organization depicting gene and protein interactions, complex phenotypes, animal societies, metapopulations, food webs and vertebrate metacommunities. Our findings suggest that nestedness emerge independently of interaction type or biological scale and reveal that disparate systems can share nested organization features characterized by inclusive subsets of interacting elements with decreasing connectedness. We primarily explore the implications of a nested structure for each of these studied systems, then theorize on how nested networks are assembled. We hypothesize that nestedness emerges across scales due to processes that, although system-dependent, may share a general compromise between two features: specificity (the number of interactions the elements of the system can have) and affinity (how these elements can be connected to each other). Our findings suggesting occurrence of nestedness

  12. Biological Parameters of Impact (United States)


    zone between no effect and gross injury or death . For example, the pilot who survives an aircraft crash, but who is injured or unconscious so that he...Biological effects were limited to one incidence of bradycardia (116 t36 t and three instances of premature ventricular contractions. However. subjeCtiY" I...R.F.Chandler INTRODUCTION -Investigation of the biological effects of abrupt acceleration (impact) was stimulated by the advent of technical advances

  13. Systems cell biology. (United States)

    Mast, Fred D; Ratushny, Alexander V; Aitchison, John D


    Systems cell biology melds high-throughput experimentation with quantitative analysis and modeling to understand many critical processes that contribute to cellular organization and dynamics. Recently, there have been several advances in technology and in the application of modeling approaches that enable the exploration of the dynamic properties of cells. Merging technology and computation offers an opportunity to objectively address unsolved cellular mechanisms, and has revealed emergent properties and helped to gain a more comprehensive and fundamental understanding of cell biology.

  14. FDA 101: Regulating Biological Products (United States)

    ... Products For Consumers Home For Consumers Consumer Updates FDA 101: Regulating Biological Products Share Tweet Linkedin Pin ... field. back to top What biological products does FDA regulate? The Center for Biologics Evaluation and Research ( ...

  15. Biological markers of oxidative stress: Applications to cardiovascular research and practice

    Directory of Open Access Journals (Sweden)

    Edwin Ho


    Full Text Available Oxidative stress is a common mediator in pathogenicity of established cardiovascular risk factors. Furthermore, it likely mediates effects of emerging, less well-defined variables that contribute to residual risk not explained by traditional factors. Functional oxidative modifications of cellular proteins, both reversible and irreversible, are a causal step in cellular dysfunction. Identifying markers of oxidative stress has been the focus of many researchers as they have the potential to act as an “integrator” of a multitude of processes that drive cardiovascular pathobiology. One of the major challenges is the accurate quantification of reactive oxygen species with very short half-life. Redox-sensitive proteins with important cellular functions are confined to signalling microdomains in cardiovascular cells and are not readily available for quantification. A popular approach is the measurement of stable by-products modified under conditions of oxidative stress that have entered the circulation. However, these may not accurately reflect redox stress at the cell/tissue level. Many of these modifications are “functionally silent”. Functional significance of the oxidative modifications enhances their validity as a proposed biological marker of cardiovascular disease, and is the strength of the redox cysteine modifications such as glutathionylation. We review selected biomarkers of oxidative stress that show promise in cardiovascular medicine, as well as new methodologies for high-throughput measurement in research and clinical settings. Although associated with disease severity, further studies are required to examine the utility of the most promising oxidative biomarkers to predict prognosis or response to treatment.

  16. Stochastic Methods in Biology

    CERN Document Server

    Kallianpur, Gopinath; Hida, Takeyuki


    The use of probabilistic methods in the biological sciences has been so well established by now that mathematical biology is regarded by many as a distinct dis­ cipline with its own repertoire of techniques. The purpose of the Workshop on sto­ chastic methods in biology held at Nagoya University during the week of July 8-12, 1985, was to enable biologists and probabilists from Japan and the U. S. to discuss the latest developments in their respective fields and to exchange ideas on the ap­ plicability of the more recent developments in stochastic process theory to problems in biology. Eighteen papers were presented at the Workshop and have been grouped under the following headings: I. Population genetics (five papers) II. Measure valued diffusion processes related to population genetics (three papers) III. Neurophysiology (two papers) IV. Fluctuation in living cells (two papers) V. Mathematical methods related to other problems in biology, epidemiology, population dynamics, etc. (six papers) An important f...

  17. Biological warfare agents

    Directory of Open Access Journals (Sweden)

    Duraipandian Thavaselvam


    Full Text Available The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies.

  18. Information Complexity and Biology (United States)

    Bagnoli, Franco; Bignone, Franco A.; Cecconi, Fabio; Politi, Antonio

    Kolmogorov contributed directly to Biology in essentially three problems: the analysis of population dynamics (Lotka-Volterra equations), the reaction-diffusion formulation of gene spreading (FKPP equation), and some discussions about Mendel's laws. However, the widely recognized importance of his contribution arises from his work on algorithmic complexity. In fact, the limited direct intervention in Biology reflects the generally slow growth of interest of mathematicians towards biological issues. From the early work of Vito Volterra on species competition, to the slow growth of dynamical systems theory, contributions to the study of matter and the physiology of the nervous system, the first 50-60 years have witnessed important contributions, but as scattered pieces apparently uncorrelated, and in branches often far away from Biology. Up to the 40' it is hard to see the initial loose build up of a convergence, for those theories that will become mainstream research by the end of the century, and connected by the study of biological systems per-se.

  19. Fostering synergy between cell biology and systems biology



    In the shared pursuit of elucidating detailed mechanisms of cell function, systems biology presents a natural complement to ongoing efforts in cell biology. Systems biology aims to characterize biological systems through integrated and quantitative modeling of cellular information. The process of model building and analysis provides value through synthesizing and cataloging information about cells and molecules; predicting mechanisms and identifying generalizable themes; generating hypotheses...

  20. Informing biological design by integration of systems and synthetic biology. (United States)

    Smolke, Christina D; Silver, Pamela A


    Synthetic biology aims to make the engineering of biology faster and more predictable. In contrast, systems biology focuses on the interaction of myriad components and how these give rise to the dynamic and complex behavior of biological systems. Here, we examine the synergies between these two fields.

  1. Biological applications of nanobiotechnology. (United States)

    de Morais, Michele Greque; Martins, Vilásia Guimarães; Steffens, Daniela; Pranke, Patricia; da Costa, Jorge Alberto Vieira


    Nanotechnology is a multidisciplinary field that covers a vast and diverse array of devices derived from engineering, physics, chemistry, and biology. Nanotechnology has opened up by rapid advances in science and technology, creating new opportunities for advances in the fields of medicine, electronics, foods, and the environment. Nanoscale structures and materials (nanoparticles, nanowires, nanofibers, nanotubes) have been explored in many biological applications (biosensing, biological separation, molecular imaging, anticancer therapy) because their novel properties and functions differ drastically from their bulk counterparts. Their high volume/surface ratio, improved solubility, and multifunctionality open many new possibilities. The objective of this review is to describe the potential benefits and impacts of the nanobiotechnology in different areas.

  2. Epigenetics: Biology's Quantum Mechanics

    Directory of Open Access Journals (Sweden)

    Richard A Jorgensen


    Full Text Available The perspective presented here is that modern genetics is at a similar stage of development as were early formulations of quantum mechanics theory in the 1920's and that in 2010 we are at the dawn of a new revolution in genetics that promises to enrich and deepen our understanding of the gene and the genome. The interrelationships and interdependence of two views of the gene - the molecular biological view and the epigenetic view - are explored, and it is argued that the classical molecular biological view is incomplete without incorporation of the epigenetic perspective and that in a sense the molecular biological view has been evolving to include the epigenetic view. Intriguingly, this evolution of the molecular view toward the broader and more inclusive epigenetic view of the gene has an intriguing, if not precise, parallel in the evolution of concepts of atomic physics from Newtonian mechanics to quantum mechanics that are interesting to consider.

  3. Epigenetics: Biology's Quantum Mechanics. (United States)

    Jorgensen, Richard A


    The perspective presented here is that modern genetics is at a similar stage of development as were early formulations of quantum mechanics theory in the 1920s and that in 2010 we are at the dawn of a new revolution in genetics that promises to enrich and deepen our understanding of the gene and the genome. The interrelationships and interdependence of two views of the gene - the molecular biological view and the epigenetic view - are explored, and it is argued that the classical molecular biological view is incomplete without incorporation of the epigenetic perspective and that in a sense the molecular biological view has been evolving to include the epigenetic view. Intriguingly, this evolution of the molecular view toward the broader and more inclusive epigenetic view of the gene has an intriguing, if not precise, parallel in the evolution of concepts of atomic physics from Newtonian mechanics to quantum mechanics that are interesting to consider.

  4. Nutritional Systems Biology

    DEFF Research Database (Denmark)

    Jensen, Kasper

    sites of diet on the disease pathway. We propose a framework for interrogating the critical targets in colon cancer process and identifying plant-based dietary interventions as important modifiers using a systems chemical biology approach. The fifth chapter of the thesis is on discovering of novel anti...... number of thoroughly selected targets. Our need for fundamental understanding of the building blocks of the complex biological systems had been the main reason for the reductionist approach that was mainly applied in the past to elucidate these systems. Nowadays, it is widely recognized that systems...... components with biological systems and their connection to health and disease. The database will be enriched with predicted interactions between food components and protein targets, based on their structural and pharmacophore similarity with known small molecule ligands. Further to this, the associations...

  5. [Biologics in SLE]. (United States)

    Karonitsch, Thomas; Aringer, Martin


    Biologics have become indispensable in the last decade in the treatment of the more common rheumatic diseases. For treating systemic lupus erythematodes (SLE), B-cell depletion, albeit off-label, has been a well-accepted strategy in severe and refractory disease. Unexpectedly, however, the results of the first randomized controlled rituximab trials in SLE were negative. New trials with improved study protocols are ongoing, which should resolve this issue. In 2012, with the approval of belimumab, SLE finally entered the era of approved biological therapies. The anti-Blys/BAFF antibody belimumab showed prevention of SLE flares, glucocorticoid sparing, and significant improvement in the quality of life of SLE patients, in part by drastically reducing immune complex mediated fatigue. Positive reports on further targeting approaches give hope that additional biological agents will be available for SLE therapy soon.

  6. Biological therapy of psoriasis

    Directory of Open Access Journals (Sweden)

    Sivamani Raja


    Full Text Available The treatment of psoriasis has undergone a revolution with the advent of biologic therapies, including infliximab, etanercept, adalimumab, efalizumab, and alefacept. These medications are designed to target specific components of the immune system and are a major technological advancement over traditional immunosuppressive medications. These usually being well tolerated are being found useful in a growing number of immune-mediated diseases, psoriasis being just one example. The newest biologic, ustekinumab, is directed against the p40 subunit of the IL-12 and IL-23 cytokines. It has provided a new avenue of therapy for an array of T-cell-mediated diseases. Biologics are generally safe; however, there has been concern over the risk of lymphoma with use of these agents. All anti-TNF-α agents have been associated with a variety of serious and "routine" opportunistic infections.

  7. Biological Soft Robotics. (United States)

    Feinberg, Adam W


    In nature, nanometer-scale molecular motors are used to generate force within cells for diverse processes from transcription and transport to muscle contraction. This adaptability and scalability across wide temporal, spatial, and force regimes have spurred the development of biological soft robotic systems that seek to mimic and extend these capabilities. This review describes how molecular motors are hierarchically organized into larger-scale structures in order to provide a basic understanding of how these systems work in nature and the complexity and functionality we hope to replicate in biological soft robotics. These span the subcellular scale to macroscale, and this article focuses on the integration of biological components with synthetic materials, coupled with bioinspired robotic design. Key examples include nanoscale molecular motor-powered actuators, microscale bacteria-controlled devices, and macroscale muscle-powered robots that grasp, walk, and swim. Finally, the current challenges and future opportunities in the field are addressed.

  8. Biological therapy and dentistry (United States)

    Radfar, Lida; Ahmadabadi, Roshanak E; Masood, Farah; Scofield, R Hal


    In recent years, a new class of drugs has revolutionized the treatment of autoimmune, allergic, infectious and many more diseases. These drugs are classified into three groups, cytokines, monoclonal antibodies and fusion proteins. Biological drugs have less side effects compared to conventional drugs, and may target special damaged cells, but not all the cells. There may be side effects such as infection, hypersensitivity, hematological disorders, cancer, hepatotoxicity and neurological disorders, but there is not enough evidence or long term studies of the mechanism of action and side effects of these drugs. Patients on biological therapy may need some special consideration in dentistry. This paper is a review regarding the classification, mechanism of action and side effects of these drugs, and dental consideration for patients on biological therapy. PMID:26372436

  9. The biology of personality. (United States)

    Mulder, R


    Historically, models of personality have generally postulated, or assumed, a link with biology. This century has witnessed a major revision of these ideas with both behavioural and psychoanalytic theorists emphasising life experiences as being largely responsible for behaviour as adults. Challenges to this assumption of the overwhelming importance of life experiences are reviewed. An extensive body of data now exists suggesting that biology contributes significantly to individual variability. This biological contribution occurs at a relatively low level in the central nervous system, best defined as temperament. Further research has suffered from the lack of a cohesive psychobiological model. Cloninger's tridimensional theory of personality is presented as a model which attempts to bridge the gap between theoretical temperamental traits, neurotransmitter function and clinical psychiatry. It is to be hoped that new theoretical models will be formulated which will focus on the importance of temperamental variables in psychiatric disorders.

  10. 7th Annual Systems Biology Symposium: Systems Biology and Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Galitski, Timothy P.


    Systems biology recognizes the complex multi-scale organization of biological systems, from molecules to ecosystems. The International Symposium on Systems Biology has been hosted by the Institute for Systems Biology in Seattle, Washington, since 2002. The annual two-day event gathers the most influential researchers transforming biology into an integrative discipline investingating complex systems. Engineering and application of new technology is a central element of systems biology. Genome-scale, or very small-scale, biological questions drive the enigneering of new technologies, which enable new modes of experimentation and computational analysis, leading to new biological insights and questions. Concepts and analytical methods in engineering are now finding direct applications in biology. Therefore, the 2008 Symposium, funded in partnership with the Department of Energy, featured global leaders in "Systems Biology and Engineering."

  11. [Cybernetics and biology]. (United States)

    Vasil'ev, G F


    Owing to methodical disadvantages, the theory of control still lacks the potential for the analysis of biological systems. To get the full benefit of the method in addition to the algorithmic model of control (as of today the only used model in the theory of control) a parametric model of control is offered to employ. The reasoning for it is explained. The approach suggested provides the possibility to use all potential of the modern theory of control for the analysis of biological systems. The cybernetic approach is shown taking a system of the rise of glucose concentration in blood as an example.

  12. PAC research in biology

    Energy Technology Data Exchange (ETDEWEB)

    Chain, C. Y., E-mail: [Universidad Nacional de La Plata, IFLP (Argentina); Ceolin, M. [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas, Dto de Quimica, Fac. Cs. Exactas, UNLP (Argentina); Pasquevich, A. F. [Universidad Nacional de La Plata, IFLP (Argentina)


    In this paper possible applications of the Perturbed Angular Correlations (PAC) technique in Biology are considered. Previous PAC experiments in biology are globally analyzed. All the work that appears in the literature has been grouped in a few research lines, just to make the analysis and discussion easy. The commonly used radioactive probes are listed and the experimental difficulties are analyzed. We also report applications of {sup 181}Hf and {sup 111}In isotopes in life sciences other than their use in PAC. The possibility of extending these studies using the PAC technique is discussed.

  13. Biological and Pharmaceutical Nanomaterials (United States)

    Kumar, Challa S. S. R.


    This first comprehensive yet concise overview of all important classes of biological and pharmaceutical nanomaterials presents in one volume the different kinds of natural biological compounds that form nanomaterials or that may be used to purposefully create them. This unique single source of information brings together the many articles published in specialized journals, which often remain unseen by members of other, related disciplines. Covering pharmaceutical, nucleic acid, peptide and DNA-Chitosan nanoparticles, the book focuses on those innovative materials and technologies needed for the continued growth of medicine, healthcare, pharmaceuticals and human wellness. For chemists, biochemists, cell biologists, materials scientists, biologists, and those working in the pharmaceutical and chemical industries.

  14. Systems biology in animal sciences

    NARCIS (Netherlands)

    Woelders, H.; Pas, te M.F.W.; Bannink, A.; Veerkamp, R.F.; Smits, M.A.


    Systems biology is a rapidly expanding field of research and is applied in a number of biological disciplines. In animal sciences, omics approaches are increasingly used, yielding vast amounts of data, but systems biology approaches to extract understanding from these data of biological processes an

  15. Plant Systems Biology (editorial) (United States)

    In June 2003, Plant Physiology published an Arabidopsis special issue devoted to plant systems biology. The intention of Natasha Raikhel and Gloria Coruzzi, the two editors of this first-of-its-kind issue, was ‘‘to help nucleate this new effort within the plant community’’ as they considered that ‘‘...

  16. Evolution, Entropy, & Biological Information (United States)

    Peterson, Jacob


    A logical question to be expected from students: "How could life develop, that is, change, evolve from simple, primitive organisms into the complex forms existing today, while at the same time there is a generally observed decline and disorganization--the second law of thermodynamics?" The explanations in biology textbooks relied upon by…

  17. Doublethink in Biological Education (United States)

    Cox, Donald D.


    Presents the material given in a talk at the 1974 convention of the National Science Teachers Association in which the author compares practices in biology education to George Orwell's concept of "doublethink," i.e., the ability to hold two contradictory beliefs in one's mind simultaneously and to accept both of them. Developments in curriculum…

  18. Next-generation biology

    DEFF Research Database (Denmark)

    Rodrigues da Fonseca, Rute Andreia; Albrechtsen, Anders; Themudo, Goncalo Espregueira Cruz;


    As sequencing technologies become more affordable, it is now realistic to propose studying the evolutionary history of virtually any organism on a genomic scale. However, when dealing with non-model organisms it is not always easy to choose the best approach given a specific biological question, ...

  19. Openers for Biology Classes. (United States)

    Gridley, C. Robert R.

    This teaching guide contains 200 activities that are suitable for openers and demonstrations in biology classes. Details are provided regarding the use of these activities. Some of the broad topics under which the activities are organized include algae, amphibians, bacteria, biologists, crustaceans, dinosaurs, ecology, evolution, flowering plants,…

  20. Biological Warfare Agents

    Directory of Open Access Journals (Sweden)

    Dev Vrat Kamboj


    Full Text Available There is a long historic record of use of biological warfare (BW agents by warring countriesagainst their enemies. However, the frequency of their use has increased since the beginningof the twentieth century. World war I witnessed the use of anthrax agent against human beingsand animals by Germans, followed by large-scale field trials by Japanese against war prisonersand Chinese population during world war II. Ironically, research and development in biologicalwarfare agents increased tremendously after the Geneva Protocol, signed in 1925, because ofits drawbacks which were overcome by Biological and Toxin Weapons Convention (BTWC in1972. Biological warfare programme took back seat after the 1972 convention but biologicalagents regained their importance after the bioterrorist attacks of anthrax powder in 2001. In thelight of these attacks, many of which turned out to be hoax, general awareness is required aboutbiological warfare agents that can be used against them. This review has been written highlightingimportant biological warfare agents, diseases caused by them, possible therapies and otherprotection measures.

  1. Diversity in Biological Molecules (United States)

    Newbury, H. John


    One of the striking characteristics of fundamental biological processes, such as genetic inheritance, development and primary metabolism, is the limited amount of variation in the molecules involved. Natural selective pressures act strongly on these core processes and individuals carrying mutations and producing slightly sub-optimal versions of…

  2. Next-generation biology

    DEFF Research Database (Denmark)

    Rodrigues da Fonseca, Rute Andreia; Albrechtsen, Anders; Themudo, Goncalo Espregueira Cruz


    we present an overview of the current sequencing technologies and the methods used in typical high-throughput data analysis pipelines. Subsequently, we contextualize high-throughput DNA sequencing technologies within their applications in non-model organism biology. We include tips regarding managing...

  3. Bayes in biological anthropology. (United States)

    Konigsberg, Lyle W; Frankenberg, Susan R


    In this article, we both contend and illustrate that biological anthropologists, particularly in the Americas, often think like Bayesians but act like frequentists when it comes to analyzing a wide variety of data. In other words, while our research goals and perspectives are rooted in probabilistic thinking and rest on prior knowledge, we often proceed to use statistical hypothesis tests and confidence interval methods unrelated (or tenuously related) to the research questions of interest. We advocate for applying Bayesian analyses to a number of different bioanthropological questions, especially since many of the programming and computational challenges to doing so have been overcome in the past two decades. To facilitate such applications, this article explains Bayesian principles and concepts, and provides concrete examples of Bayesian computer simulations and statistics that address questions relevant to biological anthropology, focusing particularly on bioarchaeology and forensic anthropology. It also simultaneously reviews the use of Bayesian methods and inference within the discipline to date. This article is intended to act as primer to Bayesian methods and inference in biological anthropology, explaining the relationships of various methods to likelihoods or probabilities and to classical statistical models. Our contention is not that traditional frequentist statistics should be rejected outright, but that there are many situations where biological anthropology is better served by taking a Bayesian approach. To this end it is hoped that the examples provided in this article will assist researchers in choosing from among the broad array of statistical methods currently available.

  4. Antiprotons get biological

    CERN Multimedia


    After its final run in September, the first results of the Antiproton Cell Experiment (ACE) look very promising. It was the first experiment to take data on the biological effects of antiproton beams to evaluate the potential of antiprotons in radiation therapy.

  5. Biology Curriculum Support Document. (United States)

    North Carolina Dept. of Public Instruction, Raleigh.

    This biology curriculum supplement includes the North Carolina Standard Course of Study Goals, helpful resources, and suggested activities supported by inquiry-based laboratory activities. Contents include a detailed description of content which provides the goals and standards being sough), a materials list for inquiry support labs and…

  6. Biological Isolation Garment (United States)


    A spinoff of astronaut's biological garment will allow hospital patients who are highly vulnerable to infection to leave their sterile habitats for several hours, carrying their germ free environment with them. Garments can be used in any of some 200 hospitals where isolation rooms are installed to treat leukemia.

  7. Commercializing Biological Control (United States)

    LeLeu, K. L.; Young, M. A.


    Describes the only commercial establishment involved in biological control in Australia. The wasp Aphitis melinus, which parasitizes the insect Red Scale, is bred in large numbers and released in the citrus groves where Red Scale is causing damage to the fruit. (JR)

  8. Biological trade and markets. (United States)

    Hammerstein, Peter; Noë, Ronald


    Cooperation between organisms can often be understood, like trade between merchants, as a mutually beneficial exchange of services, resources or other 'commodities'. Mutual benefits alone, however, are not sufficient to explain the evolution of trade-based cooperation. First, organisms may reject a particular trade if another partner offers a better deal. Second, while human trade often entails binding contracts, non-human trade requires unwritten 'terms of contract' that 'self-stabilize' trade and prevent cheating even if all traders strive to maximize fitness. Whenever trading partners can be chosen, market-like situations arise in nature that biologists studying cooperation need to account for. The mere possibility of exerting partner choice stabilizes many forms of otherwise cheatable trade, induces competition, facilitates the evolution of specialization and often leads to intricate forms of cooperation. We discuss selected examples to illustrate these general points and review basic conceptual approaches that are important in the theory of biological trade and markets. Comparing these approaches with theory in economics, it turns out that conventional models-often called 'Walrasian' markets-are of limited relevance to biology. In contrast, early approaches to trade and markets, as found in the works of Ricardo and Cournot, contain elements of thought that have inspired useful models in biology. For example, the concept of comparative advantage has biological applications in trade, signalling and ecological competition. We also see convergence between post-Walrasian economics and biological markets. For example, both economists and biologists are studying 'principal-agent' problems with principals offering jobs to agents without being sure that the agents will do a proper job. Finally, we show that mating markets have many peculiarities not shared with conventional economic markets. Ideas from economics are useful for biologists studying cooperation but need

  9. Systems biology, emergence and antireductionism. (United States)

    Kesić, Srdjan


    This study explores the conceptual history of systems biology and its impact on philosophical and scientific conceptions of reductionism, antireductionism and emergence. Development of systems biology at the beginning of 21st century transformed biological science. Systems biology is a new holistic approach or strategy how to research biological organisms, developed through three phases. The first phase was completed when molecular biology transformed into systems molecular biology. Prior to the second phase, convergence between applied general systems theory and nonlinear dynamics took place, hence allowing the formation of systems mathematical biology. The second phase happened when systems molecular biology and systems mathematical biology, together, were applied for analysis of biological data. Finally, after successful application in science, medicine and biotechnology, the process of the formation of modern systems biology was completed. Systems and molecular reductionist views on organisms were completely opposed to each other. Implications of systems and molecular biology on reductionist-antireductionist debate were quite different. The analysis of reductionism, antireductionism and emergence issues, in the era of systems biology, revealed the hierarchy between methodological, epistemological and ontological antireductionism. Primarily, methodological antireductionism followed from the systems biology. Only after, epistemological and ontological antireductionism could be supported.

  10. Quantum physics meets biology

    CERN Document Server

    Arndt, Markus; Vedral, Vlatko


    Quantum physics and biology have long been regarded as unrelated disciplines, describing nature at the inanimate microlevel on the one hand and living species on the other hand. Over the last decades the life sciences have succeeded in providing ever more and refined explanations of macroscopic phenomena that were based on an improved understanding of molecular structures and mechanisms. Simultaneously, quantum physics, originally rooted in a world view of quantum coherences, entanglement and other non-classical effects, has been heading towards systems of increasing complexity. The present perspective article shall serve as a pedestrian guide to the growing interconnections between the two fields. We recapitulate the generic and sometimes unintuitive characteristics of quantum physics and point to a number of applications in the life sciences. We discuss our criteria for a future quantum biology, its current status, recent experimental progress and also the restrictions that nature imposes on bold extrapolat...

  11. [Cell biology and cosmetology]. (United States)

    Traniello, S; Cavalletti, T


    Cellular biology can become the natural support of research in the field of cosmetics because it is able to provide alternative experimental models which can partially replace the massive use of laboratory animals. Cultures of human skin cells could be used in tests investigating irritation of the skin. We have developed an "in vitro" experimental model that allows to evaluate the damage caused by the free radicals to the fibroblasts in culture and to test the protective action of the lipoaminoacids. Experimenting on human cell cultures presents the advantage of eliminating the extrapolation between the different species, of allowing a determination of the biological action of a substance and of evaluating its dose/response effect. This does not mean that "in vitro" experimenting could completely replace experimenting on living animals, but the "in vitro" model can be introduced in the realisation of preliminary screenings.

  12. Biological scaling and physics

    Indian Academy of Sciences (India)

    A R P Rau


    Kleiber’s law in biology states that the specific metabolic rate (metabolic rate per unit mass) scales as -1/4 in terms of the mass of the organism. A long-standing puzzle is the (- 1/4) power in place of the usual expectation of (- 1/3) based on the surface to volume ratio in three-dimensions. While recent papers by physicists have focused exclusively on geometry in attempting to explain the puzzle, we consider here a specific law of physics that governs fluid flow to show how the (- 1/4) power arises under certain conditions. More generally, such a line of approach that identifies a specific physical law as involved and then examines the implications of a power law may illuminate better the role of physics in biology.

  13. Next-generation biology

    DEFF Research Database (Denmark)

    Rodrigues da Fonseca, Rute Andreia; Albrechtsen, Anders; Themudo, Gonçalo Espregueira;


    we present an overview of the current sequencing technologies and the methods used in typical high-throughput data analysis pipelines. Subsequently, we contextualize high-throughput DNA sequencing technologies within their applications in non-model organism biology. We include tips regarding managing......As sequencing technologies become more affordable, it is now realistic to propose studying the evolutionary history of virtually any organism on a genomic scale. However, when dealing with non-model organisms it is not always easy to choose the best approach given a specific biological question......, a limited budget, and challenging sample material. Furthermore, although recent advances in technology offer unprecedented opportunities for research in non-model organisms, they also demand unprecedented awareness from the researcher regarding the assumptions and limitations of each method. In this review...

  14. Quantum physics meets biology. (United States)

    Arndt, Markus; Juffmann, Thomas; Vedral, Vlatko


    Quantum physics and biology have long been regarded as unrelated disciplines, describing nature at the inanimate microlevel on the one hand and living species on the other hand. Over the past decades the life sciences have succeeded in providing ever more and refined explanations of macroscopic phenomena that were based on an improved understanding of molecular structures and mechanisms. Simultaneously, quantum physics, originally rooted in a world-view of quantum coherences, entanglement, and other nonclassical effects, has been heading toward systems of increasing complexity. The present perspective article shall serve as a "pedestrian guide" to the growing interconnections between the two fields. We recapitulate the generic and sometimes unintuitive characteristics of quantum physics and point to a number of applications in the life sciences. We discuss our criteria for a future "quantum biology," its current status, recent experimental progress, and also the restrictions that nature imposes on bold extrapolations of quantum theory to macroscopic phenomena.

  15. Biological scaling and physics. (United States)

    Rau, A R P


    Kleiber's law in biology states that the specific metabolic rate (metabolic rate per unit mass) scales as M- 1/4 in terms of the mass M of the organism. A long-standing puzzle is the (- 1/4) power in place of the usual expectation of (- 1/3) based on the surface to volume ratio in three-dimensions. While recent papers by physicists have focused exclusively on geometry in attempting to explain the puzzle, we consider here a specific law of physics that governs fluid flow to show how the (- 1/4) power arises under certain conditions. More generally, such a line of approach that identifies a specific physical law as involved and then examines the implications of a power law may illuminate better the role of physics in biology.

  16. Heritability and biological explanation. (United States)

    Turkheimer, E


    Modern neuroscientific and genetic technologies have provoked intense disagreement between scientists who envision a future in which biogenetic theories will enrich or even replace psychological theories, and others who consider biogenetic theories exaggerated, dehumanizing, and dangerous. Both sides of the debate about the role of genes and brains in the genesis of human behavior have missed an important point: All human behavior that varies among individuals is partially heritable and correlated with measurable aspects of brains, but the very ubiquity of these findings makes them a poor basis for reformulating scientists' conceptions of human behavior. Materialism requires psychological processes to be physically instantiated, but more crucial for psychology is the occasional empirical discovery of behavioral phenomena that are specific manifestations of low-level biological variables. Heritability and psychobiological association cannot be the basis for establishing whether behavior is genetic or biological, because to do so leads only to the banal tautology that all behavior is ultimately based in the genotype and brain.

  17. Topology in Molecular Biology

    CERN Document Server

    Monastyrsky, Michail Ilych


    The book presents a class of new results in molecular biology for which topological methods and ideas are important. These include: the large-scale conformation properties of DNA; computational methods (Monte Carlo) allowing the simulation of large-scale properties of DNA; the tangle model of DNA recombination and other applications of Knot theory; dynamics of supercoiled DNA and biocatalitic properties of DNA; the structure of proteins; and other very recent problems in molecular biology. The text also provides a short course of modern topology intended for the broad audience of biologists and physicists. The authors are renowned specialists in their fields and some of the new results presented here are documented for the first time in monographic form.

  18. Traceability of biologicals

    DEFF Research Database (Denmark)

    Vermeer, Niels S; Spierings, Irina; Mantel-Teeuwisse, Aukje K


    not support the routine recording of batch information. Expected changes in supply chain standards provide opportunities to systematically record detailed exposure information. Spontaneous reporting systems are the most vulnerable link in ensuring traceability, due to the manual nature of data transfer...... individual products within pharmacovigilance databases. AREAS COVERED: The authors discuss the present challenges in the traceability of biologicals in relation to pharmacovigilance, by exploring the processes involved in ensuring traceability. They explore both the existing systems that are in place...

  19. Milli-Biology (United States)


    inefficient at low RPM because power is wasted as heat in the coils, requiring gearing at low RPM, and power is required to maintain static position...soldering to join metal parts, epoxy to join the heat -sensitive permanent magnets, and screws to reversibly fasten subassemblies that might require...aerospace, and heliostat pointing for solar power. These are now transitioning to commercial development. The milli-biology workflow for coded

  20. Menstrual Cycle: Basic Biology



    The basic biology of the menstrual cycle is a complex, coordinated sequence of events involving the hypothalamus, anterior pituitary, ovary, and endometrium. The menstrual cycle with all its complexities can be easily perturbed by environmental factors such as stress, extreme exercise, eating disorders, and obesity. Furthermore, genetic influences such as fragile X premutations (Chapter X), X chromosome abnormalities (Chapter X), and galactose-1-phosphate uridyltransferase (GALT) point mutati...

  1. Biological Correlates of Empathy

    Directory of Open Access Journals (Sweden)

    E. Timucin Oral


    Full Text Available Empathy can be defined as the capacity to know emotionally what another is experiencing from within the frame of reference of that other person and the capacity to sample the feelings of another or it can be metaphorized as to put oneself in another’s shoes. Although the concept of empathy was firstly described in psychological theories, researches studying the biological correlates of psychological theories have been increasing recently. Not suprisingly, dinamically oriented psychotherapists Freud, Kohut, Basch and Fenichel had suggested theories about the biological correlates of empathy concept and established the basis of this modality decades ago. Some other theorists emphasized the importance of empathy in the early years of lifetime regarding mother-child attachment in terms of developmental psychology and investigated its role in explanation of psychopathology. The data coming from some of the recent brain imaging and animal model studies also seem to support these theories. Although increased activity in different brain regions was shown in many of the brain imaging studies, the role of cingulate cortex for understanding mother-child relationship was constantly emphasized in nearly all of the studies. In addition to these studies, a group of Italian scientists has defined a group of neurons as “mirror neurons” in their studies observing rhesus macaque monkeys. Later, they also defined mirror neurons in human studies, and suggested them as “empathy neurons”. After the discovery of mirror neurons, the hopes of finding the missing part of the puzzle for understanding the biological correlates of empathy raised again. Although the roles of different biological parameters such as skin conductance and pupil diameter for defining empathy have not been certain yet, they are going to give us the opportunity to revise the inconsistent basis of structural validity in psychiatry and to stabilize descriptive validity. In this review, the

  2. Biological therapies for spondyloarthritis


    Bruner, Vincenzo; Atteno, Mariangela; Spanò, Angelo; Scarpa, Raffaele; Peluso, Rosario


    Biological therapies and new imaging techniques have changed the therapeutic and diagnostic approach to spondyloarthritis. In patients with axial spondyloarthritis, tumor necrosis factor α (TNFα) inhibitor treatment is currently the only effective therapy in patients for whom conventional therapy with nonsteroidal anti-inflammatory drugs (NSAIDs) has failed. TNFα inhibitor treatment is more effective in preventing articular damage in peripheral joints than in axial ones. It is important to tr...

  3. Dominating biological networks.

    Directory of Open Access Journals (Sweden)

    Tijana Milenković

    Full Text Available Proteins are essential macromolecules of life that carry out most cellular processes. Since proteins aggregate to perform function, and since protein-protein interaction (PPI networks model these aggregations, one would expect to uncover new biology from PPI network topology. Hence, using PPI networks to predict protein function and role of protein pathways in disease has received attention. A debate remains open about whether network properties of "biologically central (BC" genes (i.e., their protein products, such as those involved in aging, cancer, infectious diseases, or signaling and drug-targeted pathways, exhibit some topological centrality compared to the rest of the proteins in the human PPI network.To help resolve this debate, we design new network-based approaches and apply them to get new insight into biological function and disease. We hypothesize that BC genes have a topologically central (TC role in the human PPI network. We propose two different concepts of topological centrality. We design a new centrality measure to capture complex wirings of proteins in the network that identifies as TC those proteins that reside in dense extended network neighborhoods. Also, we use the notion of domination and find dominating sets (DSs in the PPI network, i.e., sets of proteins such that every protein is either in the DS or is a neighbor of the DS. Clearly, a DS has a TC role, as it enables efficient communication between different network parts. We find statistically significant enrichment in BC genes of TC nodes and outperform the existing methods indicating that genes involved in key biological processes occupy topologically complex and dense regions of the network and correspond to its "spine" that connects all other network parts and can thus pass cellular signals efficiently throughout the network. To our knowledge, this is the first study that explores domination in the context of PPI networks.

  4. Quantum Effects in Biology (United States)

    Mohseni, Masoud; Omar, Yasser; Engel, Gregory S.; Plenio, Martin B.


    List of contributors; Preface; Part I. Introduction: 1. Quantum biology: introduction Graham R. Fleming and Gregory D. Scholes; 2. Open quantum system approaches to biological systems Alireza Shabani, Masoud Mohseni, Seogjoo Jang, Akihito Ishizaki, Martin Plenio, Patrick Rebentrost, Alàn Aspuru-Guzik, Jianshu Cao, Seth Lloyd and Robert Silbey; 3. Generalized Förster resonance energy transfer Seogjoo Jang, Hoda Hossein-Nejad and Gregory D. Scholes; 4. Multidimensional electronic spectroscopy Tomáš Mančal; Part II. Quantum Effects in Bacterial Photosynthetic Energy Transfer: 5. Structure, function, and quantum dynamics of pigment protein complexes Ioan Kosztin and Klaus Schulten; 6. Direct observation of quantum coherence Gregory S. Engel; 7. Environment-assisted quantum transport Masoud Mohseni, Alàn Aspuru-Guzik, Patrick Rebentrost, Alireza Shabani, Seth Lloyd, Susana F. Huelga and Martin B. Plenio; Part III. Quantum Effects in Higher Organisms and Applications: 8. Excitation energy transfer in higher plants Elisabet Romero, Vladimir I. Novoderezhkin and Rienk van Grondelle; 9. Electron transfer in proteins Spiros S. Skourtis; 10. A chemical compass for bird navigation Ilia A. Solov'yov, Thorsten Ritz, Klaus Schulten and Peter J. Hore; 11. Quantum biology of retinal Klaus Schulten and Shigehiko Hayashi; 12. Quantum vibrational effects on sense of smell A. M. Stoneham, L. Turin, J. C. Brookes and A. P. Horsfield; 13. A perspective on possible manifestations of entanglement in biological systems Hans J. Briegel and Sandu Popescu; 14. Design and applications of bio-inspired quantum materials Mohan Sarovar, Dörthe M. Eisele and K. Birgitta Whaley; 15. Coherent excitons in carbon nanotubes Leonas Valkunas and Darius Abramavicius; Glossary; References; Index.

  5. Synthetic biology: advancing biological frontiers by building synthetic systems


    Chen, Yvonne Yu-Hsuan; Galloway, Kate E; Smolke, Christina D.


    Advances in synthetic biology are contributing to diverse research areas, from basic biology to biomanufacturing and disease therapy. We discuss the theoretical foundation, applications, and potential of this emerging field.

  6. Biological heart valves. (United States)

    Ciubotaru, Anatol; Cebotari, Serghei; Tudorache, Igor; Beckmann, Erik; Hilfiker, Andres; Haverich, Axel


    Cardiac valvular pathologies are often caused by rheumatic fever in young adults, atherosclerosis in elderly patients, or by congenital malformation of the heart in children, in effect affecting almost all population ages. Almost 300,000 heart valve operations are performed worldwide annually. Tissue valve prostheses have certain advantages over mechanical valves such as biocompatibility, more physiological hemodynamics, and no need for life-long systemic anticoagulation. However, the major disadvantage of biological valves is related to their durability. Nevertheless, during the last decade, the number of patients undergoing biological, rather than mechanical, valve replacement has increased from half to more than three-quarters for biological implants. Continuous improvement in valve fabrication includes development of new models and shapes, novel methods of tissue treatment, and preservation and implantation techniques. These efforts are focused not only on the improvement of morbidity and mortality of the patients but also on the improvement of their quality of life. Heart valve tissue engineering aims to provide durable, "autologous" valve prostheses. These valves demonstrate adaptive growth, which may avoid the need of repeated operations in growing patients.

  7. Absolute biological needs. (United States)

    McLeod, Stephen


    Absolute needs (as against instrumental needs) are independent of the ends, goals and purposes of personal agents. Against the view that the only needs are instrumental needs, David Wiggins and Garrett Thomson have defended absolute needs on the grounds that the verb 'need' has instrumental and absolute senses. While remaining neutral about it, this article does not adopt that approach. Instead, it suggests that there are absolute biological needs. The absolute nature of these needs is defended by appeal to: their objectivity (as against mind-dependence); the universality of the phenomenon of needing across the plant and animal kingdoms; the impossibility that biological needs depend wholly upon the exercise of the abilities characteristic of personal agency; the contention that the possession of biological needs is prior to the possession of the abilities characteristic of personal agency. Finally, three philosophical usages of 'normative' are distinguished. On two of these, to describe a phenomenon or claim as 'normative' is to describe it as value-dependent. A description of a phenomenon or claim as 'normative' in the third sense does not entail such value-dependency, though it leaves open the possibility that value depends upon the phenomenon or upon the truth of the claim. It is argued that while survival needs (or claims about them) may well be normative in this third sense, they are normative in neither of the first two. Thus, the idea of absolute need is not inherently normative in either of the first two senses.

  8. Biologics for tendon repair. (United States)

    Docheva, Denitsa; Müller, Sebastian A; Majewski, Martin; Evans, Christopher H


    Tendon injuries are common and present a clinical challenge to orthopedic surgery mainly because these injuries often respond poorly to treatment and require prolonged rehabilitation. Therapeutic options used to repair ruptured tendons have consisted of suture, autografts, allografts, and synthetic prostheses. To date, none of these alternatives has provided a successful long-term solution, and often the restored tendons do not recover their complete strength and functionality. Unfortunately, our understanding of tendon biology lags far behind that of other musculoskeletal tissues, thus impeding the development of new treatment options for tendon conditions. Hence, in this review, after introducing the clinical significance of tendon diseases and the present understanding of tendon biology, we describe and critically assess the current strategies for enhancing tendon repair by biological means. These consist mainly of applying growth factors, stem cells, natural biomaterials and genes, alone or in combination, to the site of tendon damage. A deeper understanding of how tendon tissue and cells operate, combined with practical applications of modern molecular and cellular tools could provide the long awaited breakthrough in designing effective tendon-specific therapeutics and overall improvement of tendon disease management.

  9. Biological surface science (United States)

    Kasemo, Bengt


    Biological surface science (BioSS), as defined here is the broad interdisciplinary area where properties and processes at interfaces between synthetic materials and biological environments are investigated and biofunctional surfaces are fabricated. Six examples are used to introduce and discuss the subject: Medical implants in the human body, biosensors and biochips for diagnostics, tissue engineering, bioelectronics, artificial photosynthesis, and biomimetic materials. They are areas of varying maturity, together constituting a strong driving force for the current rapid development of BioSS. The second driving force is the purely scientific challenges and opportunities to explore the mutual interaction between biological components and surfaces. Model systems range from the unique water structures at solid surfaces and water shells around proteins and biomembranes, via amino and nucleic acids, proteins, DNA, phospholipid membranes, to cells and living tissue at surfaces. At one end of the spectrum the scientific challenge is to map out the structures, bonding, dynamics and kinetics of biomolecules at surfaces in a similar way as has been done for simple molecules during the past three decades in surface science. At the other end of the complexity spectrum one addresses how biofunctional surfaces participate in and can be designed to constructively participate in the total communication system of cells and tissue. Biofunctional surfaces call for advanced design and preparation in order to match the sophisticated (bio) recognition ability of biological systems. Specifically this requires combined topographic, chemical and visco-elastic patterns on surfaces to match proteins at the nm scale and cells at the micrometer scale. Essentially all methods of surface science are useful. High-resolution (e.g. scanning probe) microscopies, spatially resolved and high sensitivity, non-invasive optical spectroscopies, self-organizing monolayers, and nano- and microfabrication

  10. Molecular Biology of Nitrogen Fixation (United States)

    Shanmugam, K. T.; Valentine, Raymond C.


    Reports that as a result of our increasing knowledge of the molecular biology of nitrogen fixation it might eventually be possible to increase the biological production of nitrogenous fertilizer from atmospheric nitrogen. (GS)

  11. Is Our Biology to Blame? (United States)

    Schneider, Scott


    Brief analyses of three recent examples of biological determinism: sex roles, overpopulation, and sociobiology, are presented in this article. Also a brief discussion of biological determinism and education is presented. (MR)

  12. Logical analysis of biological systems

    DEFF Research Database (Denmark)

    Mardare, Radu Iulian


    R. Mardare, Logical analysis of biological systems. Fundamenta Informaticae, N 64:271-285, 2005.......R. Mardare, Logical analysis of biological systems. Fundamenta Informaticae, N 64:271-285, 2005....

  13. Biological treatment of Crohn's disease

    DEFF Research Database (Denmark)

    Nielsen, Ole Haagen; Bjerrum, Jacob Tveiten; Seidelin, Jakob Benedict


    Introduction of biological agents for the treatment of Crohn's disease (CD) has led to a transformation of the treatment paradigm. Several biological compounds have been approved for patients with CD refractory to conventional treatment: infliximab, adalimumab and certolizumab pegol (and...

  14. Logical impossibilities in biological networks

    Directory of Open Access Journals (Sweden)

    Monendra Grover


    Full Text Available Biological networks are complex and involve several kinds of molecules. For proper biological function it is important for these biomolecules to act at an individual level and act at the level of interaction of these molecules. In this paper some of the logical impossibilities that may arise in the biological networks and their possible solutions are discussed. It may be important to understand these paradoxes and their possible solutions in order to develop a holistic view of biological function.

  15. Biological Computing Fundamentals and Futures


    Akula, Balaji; Cusick, James


    The fields of computing and biology have begun to cross paths in new ways. In this paper a review of the current research in biological computing is presented. Fundamental concepts are introduced and these foundational elements are explored to discuss the possibilities of a new computing paradigm. We assume the reader to possess a basic knowledge of Biology and Computer Science

  16. Functions in Biological Kind Classification (United States)

    Lombrozo, Tania; Rehder, Bob


    Biological traits that serve functions, such as a zebra's coloration (for camouflage) or a kangaroo's tail (for balance), seem to have a special role in conceptual representations for biological kinds. In five experiments, we investigate whether and why functional features are privileged in biological kind classification. Experiment 1…

  17. Semiconductor nanostructures in biological applications

    Energy Technology Data Exchange (ETDEWEB)

    Alexson, Dimitri [Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Chen Hongfeng [Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Cho, Michael [Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Department of Physics, University of Illinois at Chicago, Chicago, IL 60607 (United States); Dutta, Mitra [Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Department of Physics, University of Illinois at Chicago, Chicago, IL 60607 (United States); Li Yang [Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Shi, Peng [Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Raichura, Amit [Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Ramadurai, Dinakar [Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Parikh, Shaunak [Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Stroscio, Michael A [Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Department of Physics, University of Illinois at Chicago, Chicago, IL 60607 (United States); Vasudev, Milana [Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607 (United States)


    Semiconductor nanostructures in biological applications are discussed. Results are presented on the use of colloidal semiconductor quantum dots both as biological tags and as structures that interact with and influence biomolecules. Results are presented on the use of semiconducting carbon nanotubes in biological applications. (topical review)


    Directory of Open Access Journals (Sweden)

    T. I. Burak


    Full Text Available The methodology for computer modeling of complex eco-biological models is presented in this paper. It is based on system approach of J. Forrester. Developed methodology is universal for complex ecological and biological systems. Modeling algorithm considers specialties of eco-biological systems and shows adequate and accurate results in practice. 

  19. Marine molecular biology: an emerging field of biological sciences. (United States)

    Thakur, Narsinh L; Jain, Roopesh; Natalio, Filipe; Hamer, Bojan; Thakur, Archana N; Müller, Werner E G


    An appreciation of the potential applications of molecular biology is of growing importance in many areas of life sciences, including marine biology. During the past two decades, the development of sophisticated molecular technologies and instruments for biomedical research has resulted in significant advances in the biological sciences. However, the value of molecular techniques for addressing problems in marine biology has only recently begun to be cherished. It has been proven that the exploitation of molecular biological techniques will allow difficult research questions about marine organisms and ocean processes to be addressed. Marine molecular biology is a discipline, which strives to define and solve the problems regarding the sustainable exploration of marine life for human health and welfare, through the cooperation between scientists working in marine biology, molecular biology, microbiology and chemistry disciplines. Several success stories of the applications of molecular techniques in the field of marine biology are guiding further research in this area. In this review different molecular techniques are discussed, which have application in marine microbiology, marine invertebrate biology, marine ecology, marine natural products, material sciences, fisheries, conservation and bio-invasion etc. In summary, if marine biologists and molecular biologists continue to work towards strong partnership during the next decade and recognize intellectual and technological advantages and benefits of such partnership, an exciting new frontier of marine molecular biology will emerge in the future.

  20. NASA Biological Specimen Repository (United States)

    McMonigal, K. A.; Pietrzyk, R. A.; Sams, C. F.; Johnson, M. A.


    The NASA Biological Specimen Repository (NBSR) was established in 2006 to collect, process, preserve and distribute spaceflight-related biological specimens from long duration ISS astronauts. This repository provides unique opportunities to study longitudinal changes in human physiology spanning may missions. The NBSR collects blood and urine samples from all participating ISS crewmembers who have provided informed consent. These biological samples are collected once before flight, during flight scheduled on flight days 15, 30, 60, 120 and within 2 weeks of landing. Postflight sessions are conducted 3 and 30 days after landing. The number of in-flight sessions is dependent on the duration of the mission. Specimens are maintained under optimal storage conditions in a manner that will maximize their integrity and viability for future research The repository operates under the authority of the NASA/JSC Committee for the Protection of Human Subjects to support scientific discovery that contributes to our fundamental knowledge in the area of human physiological changes and adaptation to a microgravity environment. The NBSR will institute guidelines for the solicitation, review and sample distribution process through establishment of the NBSR Advisory Board. The Advisory Board will be composed of representatives of all participating space agencies to evaluate each request from investigators for use of the samples. This process will be consistent with ethical principles, protection of crewmember confidentiality, prevailing laws and regulations, intellectual property policies, and consent form language. Operations supporting the NBSR are scheduled to continue until the end of U.S. presence on the ISS. Sample distribution is proposed to begin with selections on investigations beginning in 2017. The availability of the NBSR will contribute to the body of knowledge about the diverse factors of spaceflight on human physiology.

  1. Biology Reflective Assessment Curriculum (United States)

    Bayley, Cheryl Ann

    Often students and educators view assessments as an obligation and finality for a unit. In the current climate of high-stakes testing and accountability, the balance of time, resources and emphasis on students' scores related to assessment have been slanted considerably toward the summative side. This tension between assessment for accountability and assessment to inform teaching strains instruction and educators' ability to use that information to design learning opportunities that help students develop deeper conceptual understanding. A substantive body of research indicates that formative and reflective assessment can significantly improve student learning. Biology Reflective Assessment Curriculum (BRAC) examines support provided for high school science students through assessment practices. This investigation incorporates the usage of reflective assessments as a guiding practice for differentiated instruction and student choice. Reflective assessment is a metacognitive strategy that promotes self-monitoring and evaluation. The goals of the curriculum are to promote self-efficacy and conceptual understanding in students learning biology through developing their metacognitive awareness. BRAC was implemented in a high school biology classroom. Data from assessments, metacognitive surveys, self-efficacy surveys, reflective journals, student work, a culminating task and field notes were used to evaluate the effectiveness of the curriculum. The results suggest that students who develop their metacognitive skills developed a deeper conceptual understanding and improved feelings of self-efficacy when they were engaged in a reflective assessment unit embedded with student choice. BRAC is a tool for teachers to use assessments to assist students in becoming metacognitive and to guide student choice in learning opportunities.

  2. The Promises of Biology and the Biology of Promises

    DEFF Research Database (Denmark)

    Lee, Jieun


    commitments with differently imagined futures. I argue that promises are constitutive of the stem cell biology, rather than being derivative of it. Since the biological concept of stem cells is predicated on the future that they promise, the biological life of stem cells is inextricably intertwined...... patients’ bodies in anticipation of materializing the promises of stem cell biology, they are produced as a new form of biovaluable. The promises of biology move beyond the closed circuit of scientific knowledge production, and proliferate in the speculative marketplaces of promises. Part II looks at how...... of technologized biology and biological time can appear promising with the backdrop of the imagined intransigence of social, political, and economic order in the Korean society....

  3. Illuminating Cell Biology (United States)


    NASA's Ames Research Center awarded Ciencia, Inc., a Small Business Innovation Research contract to develop the Cell Fluorescence Analysis System (CFAS) to address the size, mass, and power constraints of using fluorescence spectroscopy in the International Space Station's Life Science Research Facility. The system will play an important role in studying biological specimen's long-term adaptation to microgravity. Commercial applications for the technology include diverse markets such as food safety, in situ environmental monitoring, online process analysis, genomics and DNA chips, and non-invasive diagnostics. Ciencia has already sold the system to the private sector for biosensor applications.

  4. Biological hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Benemann, J.R. [Univ. of California, Berkeley, CA (United States)


    Biological hydrogen production can be accomplished by either thermochemical (gasification) conversion of woody biomass and agricultural residues or by microbiological processes that yield hydrogen gas from organic wastes or water. Biomass gasification is a well established technology; however, the synthesis gas produced, a mixture of CO and H{sub 2}, requires a shift reaction to convert the CO to H{sub 2}. Microbiological processes can carry out this reaction more efficiently than conventional catalysts, and may be more appropriate for the relatively small-scale of biomass gasification processes. Development of a microbial shift reaction may be a near-term practical application of microbial hydrogen production.

  5. Biological Petri Nets

    CERN Document Server

    Wingender, E


    It was suggested some years ago that Petri nets might be well suited to modeling metabolic networks, overcoming some of the limitations encountered by the use of systems employing ODEs (ordinary differential equations). Much work has been done since then which confirms this and demonstrates the usefulness of this concept for systems biology. Petri net technology is not only intuitively understood by scientists trained in the life sciences, it also has a robust mathematical foundation and provides the required degree of flexibility. As a result it appears to be a very promising approach to mode

  6. Systems biology: experimental design. (United States)

    Kreutz, Clemens; Timmer, Jens


    Experimental design has a long tradition in statistics, engineering and life sciences, dating back to the beginning of the last century when optimal designs for industrial and agricultural trials were considered. In cell biology, the use of mathematical modeling approaches raises new demands on experimental planning. A maximum informative investigation of the dynamic behavior of cellular systems is achieved by an optimal combination of stimulations and observations over time. In this minireview, the existing approaches concerning this optimization for parameter estimation and model discrimination are summarized. Furthermore, the relevant classical aspects of experimental design, such as randomization, replication and confounding, are reviewed.

  7. Biology of Nanobots (United States)

    Duan, Wentao; Pavlick, Ryan; Sen, Ayusman


    One of the more interesting recent discoveries has been the ability to design nano/microbots which catalytically harness the chemical energy in their environment to move autonomously. Their potential applications include delivery of materials, self-assembly of superstructures, and roving sensors. One emergent area of research is the study of their collective behavior and how they emulate living systems. The aim of this chapter is to describe the "biology" of nanobots, summarizing the fundamentals physics behind their motion and how the bots interact with each other to initiate complex emergent behavior.

  8. Menstrual Cycle: Basic Biology (United States)

    Hawkins, Shannon M.; Matzuk, Martin M.


    The basic biology of the menstrual cycle is a complex, coordinated sequence of events involving the hypothalamus, anterior pituitary, ovary, and endometrium. The menstrual cycle with all its complexities can be easily perturbed by environmental factors such as stress, extreme exercise, eating disorders, and obesity. Furthermore, genetic influences such as fragile X premutations (Chapter X), X chromosome abnormalities (Chapter X), and galactose-1-phosphate uridyltransferase (GALT) point mutations (galactosemia) also contribute to perturbations of the menstrual cycle. Although not perfect, mouse model have helped to identify and confirm additional components and pathways in menstrual cycle function and dysfunction in humans. PMID:18574203

  9. [Tuberculosis and molecular biology]. (United States)

    Andersen, Ase Bengård; Lillebaek, Troels; Søborg, Christian; Johansen, Isik Somuncu; Thomsen, Vibeke Østergaard


    Mycobacterium tuberculosis, the causative agent of tuberculosis (TB) hunting millions worldwide, is a challenge to work with in the laboratory. Modern molecular biology has provided extremely useful tools which have changed conventional diagnostic procedures in the TB laboratories. Research in molecular epidemiology is currently expanding our knowledge of the natural history of TB. Access to the genome sequence has opened new avenues for research in drug development and new vaccines. However, we are still awaiting the impact of these efforts in the resource-poor TB endemic countries.

  10. Biology of Bilirubin Photoisomers. (United States)

    Hansen, Thor Willy Ruud


    Phototherapy is the main treatment for neonatal hyperbilirubinemia. In acute treatment of extreme hyperbilirubinemia, intensive phototherapy may have a role in 'detoxifying' the bilirubin molecule to more polar photoisomers, which should be less prone to crossing the blood-brain barrier, providing a 'brain-sparing' effect. This article reviews the biology of bilirubin isomers. Although there is evidence supporting the lower toxicity of bilirubin photoisomers, there are studies showing the opposite. There are methodologic weaknesses in most studies and better-designed experiments are needed. In an infant acutely threatened by bilirubin-induced brain damage, intensified phototherapy should be used expediently and aggressively.

  11. Nanoindentation of biological composites (United States)

    Dickinson, M.


    This investigation studied the effect of storage conditions on the mechanical properties as measured by nanoindentation of mineralised tissue samples. The three storage solutions were Hanks balanced salt solution, phosphate buffered saline and deionised water and all had a significant effect on the surface properties, namely hardness and modulus of enamel, dentin and bone tested. The effect was significant with a greater than 70% reduction in surface mechanical properties after 8 days immersion in the solutions. This study highlights the importance of testing biological tissues immediately after extraction, and the possible structural and chemistry changes that may occur by artificially storing the tissues.

  12. Opportunities in plant synthetic biology. (United States)

    Cook, Charis; Martin, Lisa; Bastow, Ruth


    Synthetic biology is an emerging field uniting scientists from all disciplines with the aim of designing or re-designing biological processes. Initially, synthetic biology breakthroughs came from microbiology, chemistry, physics, computer science, materials science, mathematics, and engineering disciplines. A transition to multicellular systems is the next logical step for synthetic biologists and plants will provide an ideal platform for this new phase of research. This meeting report highlights some of the exciting plant synthetic biology projects, and tools and resources, presented and discussed at the 2013 GARNet workshop on plant synthetic biology.

  13. [Biological activity of Spirulina]. (United States)

    Blinkova, L P; Gorobets, O B; Baturo, A P


    In this review information of Spirulina platensis (SP), a blue-green alga (photosynthesizing cyanobacterium) having diverse biological activity is presented. Due to high content of highly valuable proteins, indispensable amino acids, vitamins, beta-carotene and other pigments, mineral substances, indispensable fatty acids and polysaccharides, PS has been found suitable for use as bioactive additive. SP produces an immunostimulating effect by enhancing the resistance of humans, mammals, chickens and fish to infections, the capacity of influencing hemopoiesis, stimulating the production of antibodies and cytokines. Under the influence of SP macrophages, T and B cells are activated. SP sulfolipids have proved to be effective against HIV. Preparations obtained from SP biomass have also been found active against herpesvirus, cytomegalovirus, influenza virus, etc. SP extracts are capable in inhibiting cancerogenesis. SP preparations are regarded as functional products contributing to the preservation of the resident intestinal microflora, especially lactic acid bacilli and bifidobacteria, and to a decrease in the level of Candida albicans. The biological activity of SP with respect to microorganisms holds good promise for using these microalgae as components of culture media.

  14. Biological hydrogen photoproduction

    Energy Technology Data Exchange (ETDEWEB)

    Nemoto, Y. [Univ. of Miami, FL (United States)


    Following are the major accomplishments of the 6th year`s study of biological hydrogen photoproduction which were supported by DOE/NREL. (1) We have been characterizing a biological hydrogen production system using synchronously growing aerobically nitrogen-fixing unicellular cyanobacterium, Synechococcus sp. Miami BG 043511. So far it was necessary to irradiate the cells to produce hydrogen. Under darkness they did not produce hydrogen. However, we found that, if the cells are incubated with oxygen, they produce hydrogen under the dark. Under 80% argon + 20% oxygen condition, the hydrogen production activity under the dark was about one third of that under the light + argon condition. (2) Also it was necessary so far to incubate the cells under argon atmosphere to produce hydrogen in this system. Argon treatment is very expensive and should be avoided in an actual hydrogen production system. We found that, if the cells are incubated at a high cell density and in a container with minimum headspace, it is not necessary to use argon for the hydrogen production. (3) Calcium ion was found to play an important role in the mechanisms of protection of nitrogenase from external oxygen. This will be a clue to understand the reason why the hydrogen production is so resistant to oxygen in this strain. (4) In this strain, sulfide can be used as electron donor for the hydrogen production. This result shows that waste water can be used for the hydrogen production system using this strain.

  15. Synthetic biology in plastids. (United States)

    Scharff, Lars B; Bock, Ralph


    Plastids (chloroplasts) harbor a small gene-dense genome that is amenable to genetic manipulation by transformation. During 1 billion years of evolution from the cyanobacterial endosymbiont to present-day chloroplasts, the plastid genome has undergone a dramatic size reduction, mainly as a result of gene losses and the large-scale transfer of genes to the nuclear genome. Thus the plastid genome can be regarded as a naturally evolved miniature genome, the gradual size reduction and compaction of which has provided a blueprint for the design of minimum genomes. Furthermore, because of the largely prokaryotic genome structure and gene expression machinery, the high transgene expression levels attainable in transgenic chloroplasts and the very low production costs in plant systems, the chloroplast lends itself to synthetic biology applications that are directed towards the efficient synthesis of green chemicals, biopharmaceuticals and other metabolites of commercial interest. This review describes recent progress with the engineering of plastid genomes with large constructs of foreign or synthetic DNA, and highlights the potential of the chloroplast as a model system in bottom-up and top-down synthetic biology approaches.

  16. Oscillations in Mathematical Biology

    CERN Document Server


    The papers in this volume are based on talks given at a one day conference held on the campus of Adelphi University in April 1982. The conference was organized with the title "Oscillations in Mathematical Biology;" however the speakers were allowed considerable latitutde in their choice of topics. In the event, the talks all concerned the dynamics of non-linear systems arising in biology so that the conference achieved a good measure of cohesion. Some of the speakers cho~e not to submit a manuscript for these proceedings, feeling that their material was too conjectural to be committed to print. Also the paper of Rinzel and Troy is a distillation of the two separate talks that the authors gave. Otherwise the material reproduces the conference proceedings. The conference was made possible by the generous support of the Office of the Dean of the College of Arts and Sciences at Adelphi. The bulk of the organization of the conference was carried out by Dr. Ronald Grisell whose energy was in large measure responsib...

  17. Neutron instrumentation for biology

    Energy Technology Data Exchange (ETDEWEB)

    Mason, S.A. [Institut Laue-Langevin, Grenoble (France)


    In the October 1994 round of proposals at the ILL, the external biology review sub- committee was asked to allocate neutron beam time to a wide range of experiments, on almost half the total number of scheduled neutron instruments: on 3 diffractometers, on 3 small angle scattering instruments, and on some 6 inelastic scattering spectrometers. In the 3.5 years since the temporary reactor shutdown, the ILL`s management structure has been optimized, budgets and staff have been trimmed, the ILL reactor has been re-built, and many of the instruments up-graded, many powerful (mainly Unix) workstations have been introduced, and the neighboring European Synchrotron Radiation Facility has established itself as the leading synchrotron radiation source and has started its official user program. The ILL reactor remains the world`s most intense dedicated neutron source. In this challenging context, it is of interest to review briefly the park of ILL instruments used to study the structure and energetics of small and large biological systems. A brief summary will be made of each class of experiments actually proposed in the latest ILL proposal round.

  18. Industrial systems biology. (United States)

    Otero, José Manuel; Nielsen, Jens


    The chemical industry is currently undergoing a dramatic change driven by demand for developing more sustainable processes for the production of fuels, chemicals, and materials. In biotechnological processes different microorganisms can be exploited, and the large diversity of metabolic reactions represents a rich repository for the design of chemical conversion processes that lead to efficient production of desirable products. However, often microorganisms that produce a desirable product, either naturally or because they have been engineered through insertion of heterologous pathways, have low yields and productivities, and in order to establish an economically viable process it is necessary to improve the performance of the microorganism. Here metabolic engineering is the enabling technology. Through metabolic engineering the metabolic landscape of the microorganism is engineered such that there is an efficient conversion of the raw material, typically glucose, to the product of interest. This process may involve both insertion of new enzymes activities, deletion of existing enzyme activities, but often also deregulation of existing regulatory structures operating in the cell. In order to rapidly identify the optimal metabolic engineering strategy the industry is to an increasing extent looking into the use of tools from systems biology. This involves both x-ome technologies such as transcriptome, proteome, metabolome, and fluxome analysis, and advanced mathematical modeling tools such as genome-scale metabolic modeling. Here we look into the history of these different techniques and review how they find application in industrial biotechnology, which will lead to what we here define as industrial systems biology.

  19. Mathematical modeling of biological processes

    CERN Document Server

    Friedman, Avner


    This book on mathematical modeling of biological processes includes a wide selection of biological topics that demonstrate the power of mathematics and computational codes in setting up biological processes with a rigorous and predictive framework. Topics include: enzyme dynamics, spread of disease, harvesting bacteria, competition among live species, neuronal oscillations, transport of neurofilaments in axon, cancer and cancer therapy, and granulomas. Complete with a description of the biological background and biological question that requires the use of mathematics, this book is developed for graduate students and advanced undergraduate students with only basic knowledge of ordinary differential equations and partial differential equations; background in biology is not required. Students will gain knowledge on how to program with MATLAB without previous programming experience and how to use codes in order to test biological hypothesis.

  20. Protein microarrays for systems biology

    Institute of Scientific and Technical Information of China (English)

    Lina Yang; Shujuan Guo; Yang Li; Shumin Zhou; Shengce Tao


    Systems biology holds the key for understanding biological systems on a system level. It eventually holds the key for the treatment and cure of complex diseases such as cancer,diabetes, obesity, mental disorders, and many others. The '-omics' technologies, such as genomics, transcriptomics,proteomics, and metabonomics, are among the major driving forces of systems biology. Featured as highthroughput, miniaturized, and capable of parallel analysis,protein microarrays have already become an important technology platform for systems biology, In this review, we will focus on the system level or global analysis of biological systems using protein microarrays. Four major types of protein microarrays will be discussed: proteome microarrays, antibody microarrays, reverse-phase protein arrays,and lectin microarrays. We will also discuss the challenges and future directions of protein microarray technologies and their applications for systems biology. We strongly believe that protein microarrays will soon become an indispensable and invaluable tool for systems biology.

  1. Microgravity Fluids for Biology, Workshop (United States)

    Griffin, DeVon; Kohl, Fred; Massa, Gioia D.; Motil, Brian; Parsons-Wingerter, Patricia; Quincy, Charles; Sato, Kevin; Singh, Bhim; Smith, Jeffrey D.; Wheeler, Raymond M.


    Microgravity Fluids for Biology represents an intersection of biology and fluid physics that present exciting research challenges to the Space Life and Physical Sciences Division. Solving and managing the transport processes and fluid mechanics in physiological and biological systems and processes are essential for future space exploration and colonization of space by humans. Adequate understanding of the underlying fluid physics and transport mechanisms will provide new, necessary insights and technologies for analyzing and designing biological systems critical to NASAs mission. To enable this mission, the fluid physics discipline needs to work to enhance the understanding of the influence of gravity on the scales and types of fluids (i.e., non-Newtonian) important to biology and life sciences. In turn, biomimetic, bio-inspired and synthetic biology applications based on physiology and biology can enrich the fluid mechanics and transport phenomena capabilities of the microgravity fluid physics community.

  2. Synthetic biology: ethical ramifications 2009. (United States)

    Rabinow, Paul; Bennett, Gaymon


    During 2007 and 2008 synthetic biology moved from the manifesto stage to research programs. As of 2009, synthetic biology is ramifying; to ramify means to produce differentiated trajectories from previous determinations. From its inception, most of the players in synthetic biology agreed on the need for (a) rationalized design and construction of new biological parts, devices, and systems as well as (b) the re-design of natural biological systems for specified purposes, and that (c) the versatility of designed biological systems makes them suitable to address such challenges as renewable energy, the production of inexpensive drugs, and environmental remediation, as well as providing a catalyst for further growth of biotechnology. What is understood by these goals, however, is diverse. Those assorted understandings are currently contributing to different ramifications of synthetic biology. The Berkeley Human Practices Lab, led by Paul Rabinow, is currently devoting its efforts to documenting and analyzing these ramifications as they emerge.

  3. Bridging the gap between systems biology and synthetic biology. (United States)

    Liu, Di; Hoynes-O'Connor, Allison; Zhang, Fuzhong


    Systems biology is an inter-disciplinary science that studies the complex interactions and the collective behavior of a cell or an organism. Synthetic biology, as a technological subject, combines biological science and engineering, allowing the design and manipulation of a system for certain applications. Both systems and synthetic biology have played important roles in the recent development of microbial platforms for energy, materials, and environmental applications. More importantly, systems biology provides the knowledge necessary for the development of synthetic biology tools, which in turn facilitates the manipulation and understanding of complex biological systems. Thus, the combination of systems and synthetic biology has huge potential for studying and engineering microbes, especially to perform advanced tasks, such as producing biofuels. Although there have been very few studies in integrating systems and synthetic biology, existing examples have demonstrated great power in extending microbiological capabilities. This review focuses on recent efforts in microbiological genomics, transcriptomics, proteomics, and metabolomics, aiming to fill the gap between systems and synthetic biology.

  4. Molecular biology of potyviruses. (United States)

    Revers, Frédéric; García, Juan Antonio


    Potyvirus is the largest genus of plant viruses causing significant losses in a wide range of crops. Potyviruses are aphid transmitted in a nonpersistent manner and some of them are also seed transmitted. As important pathogens, potyviruses are much more studied than other plant viruses belonging to other genera and their study covers many aspects of plant virology, such as functional characterization of viral proteins, molecular interaction with hosts and vectors, structure, taxonomy, evolution, epidemiology, and diagnosis. Biotechnological applications of potyviruses are also being explored. During this last decade, substantial advances have been made in the understanding of the molecular biology of these viruses and the functions of their various proteins. After a general presentation on the family Potyviridae and the potyviral proteins, we present an update of the knowledge on potyvirus multiplication, movement, and transmission and on potyvirus/plant compatible interactions including pathogenicity and symptom determinants. We end the review providing information on biotechnological applications of potyviruses.

  5. Networks in Cell Biology (United States)

    Buchanan, Mark; Caldarelli, Guido; De Los Rios, Paolo; Rao, Francesco; Vendruscolo, Michele


    Introduction; 1. Network views of the cell Paolo De Los Rios and Michele Vendruscolo; 2. Transcriptional regulatory networks Sarath Chandra Janga and M. Madan Babu; 3. Transcription factors and gene regulatory networks Matteo Brilli, Elissa Calistri and Pietro Lió; 4. Experimental methods for protein interaction identification Peter Uetz, Björn Titz, Seesandra V. Rajagopala and Gerard Cagney; 5. Modeling protein interaction networks Francesco Rao; 6. Dynamics and evolution of metabolic networks Daniel Segré; 7. Hierarchical modularity in biological networks: the case of metabolic networks Erzsébet Ravasz Regan; 8. Signalling networks Gian Paolo Rossini; Appendix 1. Complex networks: from local to global properties D. Garlaschelli and G. Caldarelli; Appendix 2. Modelling the local structure of networks D. Garlaschelli and G. Caldarelli; Appendix 3. Higher-order topological properties S. Ahnert, T. Fink and G. Caldarelli; Appendix 4. Elementary mathematical concepts A. Gabrielli and G. Caldarelli; References.

  6. The biology of strigolactones

    KAUST Repository

    Ruyter-Spira, Carolien P.


    The strigolactones are rhizosphere signaling molecules as well as a new class of plant hormones with a still increasing number of biological functions being uncovered. Here, we review a recent major breakthrough in our understanding of strigolactone biosynthesis, which has revealed the unexpected simplicity of the originally postulated complex pathway. Moreover, the discovery and localization of a strigolactone exporter sheds new light on putative strigolactone fluxes to the rhizosphere as well as within the plant. The combination of these data with information on the expression and regulation of strigolactone biosynthetic and downstream signaling genes provides new insights into how strigolactones control the many different aspects of plant development and how their rhizosphere signaling role may have evolved. © 2012 Elsevier Ltd.

  7. Plant Vascular Biology 2010

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Biao


    This grant supported the Second International Conference on Plant Vascular Biology (PVB 2010) held July 24-28, 2010 on the campus of Ohio State University, Columbus, Ohio. Biao Ding (Ohio State University; OSU) and David Hannapel (Iowa State University; ISU) served as co-chairs of this conference. Biao Ding served as the local organizer. PVB is defined broadly here to include studies on the biogenesis, structure and function of transport systems in plants, under conditions of normal plant growth and development as well as of plant interactions with pathogens. The transport systems cover broadly the xylem, phloem, plasmodesmata and vascular cell membranes. The PVB concept has emerged in recent years to emphasize the integrative nature of the transport systems and approaches to investigate them.

  8. A Biologically Inspired Classifier

    CERN Document Server

    Bagnoli, Franco


    We present a method for measuring the distance among records based on the correlations of data stored in the corresponding database entries. The original method (F. Bagnoli, A. Berrones and F. Franci. Physica A 332 (2004) 509-518) was formulated in the context of opinion formation. The opinions expressed over a set of topic originate a ``knowledge network'' among individuals, where two individuals are nearer the more similar their expressed opinions are. Assuming that individuals' opinions are stored in a database, the authors show that it is possible to anticipate an opinion using the correlations in the database. This corresponds to approximating the overlap between the tastes of two individuals with the correlations of their expressed opinions. In this paper we extend this model to nonlinear matching functions, inspired by biological problems such as microarray (probe-sample pairing). We investigate numerically the error between the correlation and the overlap matrix for eight sequences of reference with r...

  9. Biology of Sexual Dysfunction

    Directory of Open Access Journals (Sweden)

    Anil Kumar Mysore Nagaraj


    Full Text Available Sexual activity is a multifaceted activity, involving complex interactions between the nervous system, the endocrine system, the vascular system and a variety of structures that are instrumental in sexual excitement, intercourse and satisfaction. Sexual function has three components i.e., desire, arousal and orgasm. Many sexual dysfunctions can be categorized according to the phase of sexual response that is affected. In actual clinical practice however, sexual desire, arousal and orgasmic difficulties more often than not coexist, suggesting an integration of phases. Sexual dysfunction can result from a wide variety of psychological and physiological causes including derangements in the levels of sex hormones and neurotrensmitters. This review deals with the biology of different phases of sexual function as well as implications of hormones and neurotransmitters in sexual dysfunction

  10. Evolutionary biology of cancer. (United States)

    Crespi, Bernard; Summers, Kyle


    Cancer is driven by the somatic evolution of cell lineages that have escaped controls on replication and by the population-level evolution of genes that influence cancer risk. We describe here how recent evolutionary ecological studies have elucidated the roles of predation by the immune system and competition among normal and cancerous cells in the somatic evolution of cancer. Recent analyses of the evolution of cancer at the population level show how rapid changes in human environments have augmented cancer risk, how strong selection has frequently led to increased cancer risk as a byproduct, and how anticancer selection has led to tumor-suppression systems, tissue designs that slow somatic evolution, constraints on morphological evolution and even senescence itself. We discuss how applications of the tools of ecology and evolutionary biology are poised to revolutionize our understanding and treatment of this disease.

  11. Biology of Schwann cells. (United States)

    Kidd, Grahame J; Ohno, Nobuhiko; Trapp, Bruce D


    The fundamental roles of Schwann cells during peripheral nerve formation and regeneration have been recognized for more than 100 years, but the cellular and molecular mechanisms that integrate Schwann cell and axonal functions continue to be elucidated. Derived from the embryonic neural crest, Schwann cells differentiate into myelinating cells or bundle multiple unmyelinated axons into Remak fibers. Axons dictate which differentiation path Schwann cells follow, and recent studies have established that axonal neuregulin1 signaling via ErbB2/B3 receptors on Schwann cells is essential for Schwann cell myelination. Extracellular matrix production and interactions mediated by specific integrin and dystroglycan complexes are also critical requisites for Schwann cell-axon interactions. Myelination entails expansion and specialization of the Schwann cell plasma membrane over millimeter distances. Many of the myelin-specific proteins have been identified, and transgenic manipulation of myelin genes have provided novel insights into myelin protein function, including maintenance of axonal integrity and survival. Cellular events that facilitate myelination, including microtubule-based protein and mRNA targeting, and actin based locomotion, have also begun to be understood. Arguably, the most remarkable facet of Schwann cell biology, however, is their vigorous response to axonal damage. Degradation of myelin, dedifferentiation, division, production of axonotrophic factors, and remyelination all underpin the substantial regenerative capacity of the Schwann cells and peripheral nerves. Many of these properties are not shared by CNS fibers, which are myelinated by oligodendrocytes. Dissecting the molecular mechanisms responsible for the complex biology of Schwann cells continues to have practical benefits in identifying novel therapeutic targets not only for Schwann cell-specific diseases but other disorders in which axons degenerate.

  12. The Promises of Biology and the Biology of Promises

    DEFF Research Database (Denmark)

    Lee, Jieun


    This dissertation considers the ontology of stem cells as a future-oriented life form characterized by its potentiality in relation to the anticipatory mode of living in contemporary Korea. The biological notion that stem cells have the potential for differentiation and the capacity for self-rene...... of technologized biology and biological time can appear promising with the backdrop of the imagined intransigence of social, political, and economic order in the Korean society....

  13. Systems biology: a biologist's viewpoint. (United States)

    Bose, Biplab


    The debate over reductionism and antireductionism in biology is very old. Even the systems approach in biology is more than five decades old. However, mainstream biology, particularly experimental biology, has broadly sidestepped those debates and ideas. Post-genome data explosion and development of high-throughput techniques led to resurfacing of those ideas and debates as a new incarnation called Systems Biology. Though experimental biologists have co-opted systems biology and hailed it as a paradigm shift, it is practiced in different shades and understood with divergent meanings. Biology has certain questions linked with organization of multiple components and processes. Often such questions involve multilevel systems. Here in this essay we argue that systems theory provides required framework and abstractions to explore those questions. We argue that systems biology should follow the logical and mathematical approach of systems theory and transmogrification of systems biology to mere collection of higher dimensional data must be avoided. Therefore, the questions that we ask and the priority of those questions should also change. Systems biology should focus on system-level properties and investigate complexity without shying away from it.

  14. Biology of biological meshes used in hernia repair. (United States)

    Novitsky, Yuri W


    Successful repair of most hernias requires the use of a prosthetic implant for reinforcement of the defect. Because of the need for prosthetic implants to resist infections as well to support repairs in contaminated or potentially contaminated fields, biological meshes have been developed to take the place of nondegradable synthetic meshes in cases where mesh infection is of high concern. The ideal is a biological matrix that resists infection while providing durable reinforcement of a hernia repair. This article reviews the validity of assumptions that support the purported notion of the biological behavior of biological meshes.

  15. Biological half-lives and organ distribution of tritiated 8-lysine-vasopressin and 1-deamino-8-D-arginine-vasopressin in Brattleboro rats

    Energy Technology Data Exchange (ETDEWEB)

    Janaky, T.; Laczi, F.; Laszlo, F.A.


    The biological half-lives and organ distribution of tritiated 8-lysine-vasopressin and 1-deamino-8-D-arginine-vasopressin were determined in R-Amsterdam rats and in homozygous and heterozygous Brattleboro rats with hereditary central diabetes insipidus. It was found that the biological half-lives of (/sup 3/H)LVP and (/sup 3/H)dDAVP in the Brattleboro rats did not differ significantly from that found in the control R-Amsterdam rats. The half-life of (/sup 3/H)dDAVP proved longer than that of (/sup 3/H)LVP in all three groups of animals. In the case of (/sup 3/H)LVP the highest radioactivities were observed in the neurohypophyses, adenohypophyses, and kidneys of both the R-Amsterdam and Brattleboro rats. The accumulation of tritiated material was higher in the small intestine of the Brattleboro rats than in that of the R-Amsterdam animals. In all three groups of rats, (/sup 3/H)dDAVP was accumulated to the greatest extent in the kidney and the small intestine. The kidney and small intestine contained less radioactivity in homozygous Brattleboro rats than in the controls. There was only a slight radioactivity accumulation in the adenohypophysis and neurohypophysis. From the results it was concluded that the decrease in the rate of enzymatic decomposition may play a role in the increased duration of antidiuretic action of dDAVP. The results have led to the conclusion that the accelerated elimination of vasopressin and its pathologic organ accumulation are probably not involved in the water metabolism disturbance of Brattleboro rats with hereditary diabetes insipidus.

  16. Microfluidic Technologies for Synthetic Biology

    Directory of Open Access Journals (Sweden)

    Sung Kuk Lee


    Full Text Available Microfluidic technologies have shown powerful abilities for reducing cost, time, and labor, and at the same time, for increasing accuracy, throughput, and performance in the analysis of biological and biochemical samples compared with the conventional, macroscale instruments. Synthetic biology is an emerging field of biology and has drawn much attraction due to its potential to create novel, functional biological parts and systems for special purposes. Since it is believed that the development of synthetic biology can be accelerated through the use of microfluidic technology, in this review work we focus our discussion on the latest microfluidic technologies that can provide unprecedented means in synthetic biology for dynamic profiling of gene expression/regulation with high resolution, highly sensitive on-chip and off-chip detection of metabolites, and whole-cell analysis.

  17. Quantum Effects in Biological Systems

    CERN Document Server


    Since the last decade the study of quantum mechanical phenomena in biological systems has become a vibrant field of research. Initially sparked by evidence of quantum effects in energy transport that is instrumental for photosynthesis, quantum biology asks the question of how methods and models from quantum theory can help us to understand fundamental mechanisms in living organisms. This approach entails a paradigm change challenging the related disciplines: The successful framework of quantum theory is taken out of its low-temperature, microscopic regimes and applied to hot and dense macroscopic environments, thereby extending the toolbox of biology and biochemistry at the same time. The Quantum Effects in Biological Systems conference is a platform for researchers from biology, chemistry and physics to present and discuss the latest developments in the field of quantum biology. After meetings in Lisbon (2009), Harvard (2010), Ulm (2011), Berkeley (2012), Vienna (2013), Singapore (2014) and Florence (2015),...

  18. Values, Advocay and Conservation Biology



    In this essay, I examine the controversy concerning the advocacy of ethical values in conservation biology. First, I argue, as others have, that conservation biology is a science laden with values both ethical and non-ethical. Second, after clarifying the notion of advocacy at work, I contend that conservation biologists should advocate the preservation of biological diversity. Third, I explore what ethical grounds should be used for advocating the preservation of ecological systems by conser...

  19. Relations between intuitive biological thinking and biological misconceptions in biology majors and nonmajors. (United States)

    Coley, John D; Tanner, Kimberly


    Research and theory development in cognitive psychology and science education research remain largely isolated. Biology education researchers have documented persistent scientifically inaccurate ideas, often termed misconceptions, among biology students across biological domains. In parallel, cognitive and developmental psychologists have described intuitive conceptual systems--teleological, essentialist, and anthropocentric thinking--that humans use to reason about biology. We hypothesize that seemingly unrelated biological misconceptions may have common origins in these intuitive ways of knowing, termed cognitive construals. We presented 137 undergraduate biology majors and nonmajors with six biological misconceptions. They indicated their agreement with each statement, and explained their rationale for their response. Results indicate frequent agreement with misconceptions, and frequent use of construal-based reasoning among both biology majors and nonmajors in their written explanations. Moreover, results also show associations between specific construals and the misconceptions hypothesized to arise from those construals. Strikingly, such associations were stronger among biology majors than nonmajors. These results demonstrate important linkages between intuitive ways of thinking and misconceptions in discipline-based reasoning, and raise questions about the origins, persistence, and generality of relations between intuitive reasoning and biological misconceptions.

  20. NASA space biology accomplishments, 1982 (United States)

    Halstead, T. W.; Pleasant, L. G.


    Summaries of NASA's Space Biology Program projects are provided. The goals, objectives, accomplishments, and future plans of each project are described in this publication as individual technical summaries.

  1. Engineering Nanoscale Biological Molecular Motors


    Korosec, Chapin; Forde, Nancy R.


    Understanding the operation of biological molecular motors, nanoscale machines that transduce electrochemical energy into mechanical work, is enhanced by bottom-up strategies to synthesize novel motors.

  2. Telemetry System of Biological Parameters

    Directory of Open Access Journals (Sweden)

    Jan Spisak


    Full Text Available The mobile telemetry system of biological parameters serves for reading and wireless data transfer of measured values of selected biological parameters to an outlying computer. It concerns basically long time monitoring of vital function of car pilot.The goal of this projects is to propose mobile telemetry system for reading, wireless transfer and processing of biological parameters of car pilot during physical and psychical stress. It has to be made with respect to minimal consumption, weight and maximal device mobility. This system has to eliminate signal noise, which is created by biological artifacts and disturbances during the data transfer.

  3. Biological and medical sensor technologies

    CERN Document Server

    Iniewski, Krzysztof


    Biological and Medical Sensor Technologies presents contributions from top experts who explore the development and implementation of sensors for various applications used in medicine and biology. Edited by a pioneer in the area of advanced semiconductor materials, the book is divided into two sections. The first part covers sensors for biological applications. Topics include: Advanced sensing and communication in the biological world DNA-derivative architectures for long-wavelength bio-sensing Label-free silicon photonics Quartz crystal microbalance-based biosensors Lab-on-chip technologies fo

  4. American Institute of Biological Sciences (United States)

    ... organizations advancing biology through membership in AIBS News Trump's FY 2018 Budget Request Would Slash Most Science Programs President Trump's first budget request seeks historically deep budget cuts ...

  5. Synthetic biology for therapeutic applications. (United States)

    Abil, Zhanar; Xiong, Xiong; Zhao, Huimin


    Synthetic biology is a relatively new field with the key aim of designing and constructing biological systems with novel functionalities. Today, synthetic biology devices are making their first steps in contributing new solutions to a number of biomedical challenges, such as emerging bacterial antibiotic resistance and cancer therapy. This review discusses some synthetic biology approaches and applications that were recently used in disease mechanism investigation and disease modeling, drug discovery and production, as well as vaccine development and treatment of infectious diseases, cancer, and metabolic disorders.

  6. Computer algebra in systems biology

    CERN Document Server

    Laubenbacher, Reinhard


    Systems biology focuses on the study of entire biological systems rather than on their individual components. With the emergence of high-throughput data generation technologies for molecular biology and the development of advanced mathematical modeling techniques, this field promises to provide important new insights. At the same time, with the availability of increasingly powerful computers, computer algebra has developed into a useful tool for many applications. This article illustrates the use of computer algebra in systems biology by way of a well-known gene regulatory network, the Lac Operon in the bacterium E. coli.

  7. Bioinspired materials: Boosting plant biology (United States)

    Scholes, Gregory D.; Sargent, Edward H.


    Chloroplasts with extended photosynthetic activity beyond the visible absorption spectrum, and living leaves that perform non-biological functions, are made possible by localizing nanoparticles within plant organelles.

  8. Rotating Biological Contractors (RBC's). Instructor's Guide. Biological Treatment Process Control. (United States)

    Zickefoose, Charles S.

    This two-lesson unit on rotating biological contactors (RBC's) is designed to be used with students who have had some experience in wastewater treatment and a basic understanding of biological treatment. The first lesson provides information on the concepts and components of RBC treatment systems. The second lesson focuses on design operation and…

  9. Exploring Visuomotor Priming Following Biological and Non-Biological Stimuli (United States)

    Gowen, E.; Bradshaw, C.; Galpin, A.; Lawrence, A.; Poliakoff, E.


    Observation of human actions influences the observer's own motor system, termed visuomotor priming, and is believed to be caused by automatic activation of mirror neurons. Evidence suggests that priming effects are larger for biological (human) as opposed to non-biological (object) stimuli and enhanced when viewing stimuli in mirror compared to…

  10. Quantitative biology: where modern biology meets physical sciences. (United States)

    Shekhar, Shashank; Zhu, Lian; Mazutis, Linas; Sgro, Allyson E; Fai, Thomas G; Podolski, Marija


    Quantitative methods and approaches have been playing an increasingly important role in cell biology in recent years. They involve making accurate measurements to test a predefined hypothesis in order to compare experimental data with predictions generated by theoretical models, an approach that has benefited physicists for decades. Building quantitative models in experimental biology not only has led to discoveries of counterintuitive phenomena but has also opened up novel research directions. To make the biological sciences more quantitative, we believe a two-pronged approach needs to be taken. First, graduate training needs to be revamped to ensure biology students are adequately trained in physical and mathematical sciences and vice versa. Second, students of both the biological and the physical sciences need to be provided adequate opportunities for hands-on engagement with the methods and approaches necessary to be able to work at the intersection of the biological and physical sciences. We present the annual Physiology Course organized at the Marine Biological Laboratory (Woods Hole, MA) as a case study for a hands-on training program that gives young scientists the opportunity not only to acquire the tools of quantitative biology but also to develop the necessary thought processes that will enable them to bridge the gap between these disciplines.

  11. "Protected biological control"- Biological pest management in the greenhouse industry

    NARCIS (Netherlands)

    Pilkington, L.J.; Messelink, G.J.; Lenteren, van J.C.; Mottee, Le K.


    This paper briefly describes the foundations and characteristics of biological control in protected cropping and what drivers are behind adoption of this management system within this industry. Examining a brief history of biological control in greenhouses and what makes it a successful management s

  12. Crystallogenesis of biological macromolecules. Biological, microgravity and other physicochemical aspects

    NARCIS (Netherlands)

    Giege, R; Drenth, J; Ducruix, A; McPherson, A; Saenger, W


    After an historical introduction and justification of the importance of proteins (as well as other macromolecules or macromolecular assemblies of biological origin) in modern biology but also in physics, this review presents the state of the field of macromolecular crystallogenesis. The basic questi

  13. [Hemodialysis with biological object]. (United States)

    Eventov, V L; Maksimenko, V A; Zhidkov, I L; Andrianova, M Iu


    The essence of the method of biodialysis (hemodialysis with biological object) developed and suggested by the authors for clinical use consists in that the healthy organism exerts, through a system of mass transfer, a therapeutic action on the sick organism. Blood from the affected and healthy organisms is perfused through individual mass exchangers (dialyzers, hemodiafilters and hemofilters), which are hydraulically connected by a circulating transport medium. Metabolites that accumulate in blood of the affected organism diffuse into the transport medium and, from there, into blood of the healthy organism, which metabolizes them. The reverse process occurs simultaneously: substances, whose concentration in blood of the sick organism is less versus the healthy organism, diffuse from blood of the healthy organism to blood of patient. The method suggested by us can be used in clinical practice for normalizing a variety of parameters in patients with hepatic and renal insufficiency. Besides, a number of substances can be transferred from the healthy donor to patient in the process of biodialysis, which opens promising potentialities for the treatment of many diseases.

  14. Consciousness and biological evolution. (United States)

    Lindahl, B I


    It has been suggested that if the preservation and development of consciousness in the biological evolution is a result of natural selection, it is plausible that consciousness not only has been influenced by neural processes, but has had a survival value itself; and it could only have had this, if it had also been efficacious. This argument for mind-brain interaction is examined, both as the argument has been developed by William James and Karl Popper and as it has been discussed by C.D. Broad. The problem of identifying mental phenomena with certain neural phenomena is also addressed. The main conclusion of the analysis is that an explanation of the evolution of consciousness in Darwinian terms of natural selection does not rule out that consciousness may have evolved as a mere causally inert effect of the evolution of the nervous system, or that mental phenomena are identical with certain neural phenomena. However, the interactionistic theory still seems, more plausible and more fruitful for other reasons brought up in the discussion.

  15. Flotation of Biological Materials

    Directory of Open Access Journals (Sweden)

    George Z. Kyzas


    Full Text Available Flotation constitutes a gravity separation process, which originated from the minerals processing field. However, it has, nowadays, found several other applications, as for example in the wastewater treatment field. Concerning the necessary bubble generation method, typically dispersed-air or dissolved-air flotation was mainly used. Various types of biological materials were tested and floated efficiently, such as bacteria, fungi, yeasts, activated sludge, grape stalks, etc. Innovative processes have been studied in our Laboratory, particularly for metal ions removal, involving the initial abstraction of heavy metal ions onto a sorbent (including a biosorbent: in the first, the application of a flotation stage followed for the efficient downstream separation of metal-laden particles. The ability of microorganisms to remove metal ions from dilute aqueous solutions (as most wastewaters are is a well-known property. The second separation process, also applied effectively, was a new hybrid cell of microfiltration combined with flotation. Sustainability in this field and its significance for the chemical and process industry is commented.

  16. [Biology molecular of glioblastomas]. (United States)

    Franco-Hernández, C; Martínez-Glez, V; Rey, J A


    Glioblastomas, the most frequent and malignant human brain tumors, may develop de novo (primary glioblastoma) or by progression from low-grade or anapalsic astrocytoma (secondary glioblastoma). The molecular alteration most frequent in these tumor-like types is the loss of heterozygosity on chromosome 10, in which several genes have been identified as tumors suppressor. The TP53/MDM2/P14arf and CDK4/RB1/ P16ink4 genetic pathways involved in cycle control are deregulated in the majority of gliomas as well as genes that promote the cellular division, EGFR. Finally the increase of growth and angiogenics factors is also involved in the development of glioblastomas. One of the objectives of molecular biology in tumors of glial ancestry is to try to find the genetic alterations that allow to approach better the classification of glioblastomas, its evolution prediction and treatment. The new pathmolecular classification of gliomas should improve the old one, especially being concerned about the oncogenesis and heterogeneity of these tumors. It is desirable that this classification had clinical applicability and integrates new molecular findings with some known histological features with pronostic value. In this paper we review the most frequent molecular mechanisms involved in the patogenesis of glioblastomas.

  17. Mesangial cell biology

    Energy Technology Data Exchange (ETDEWEB)

    Abboud, Hanna E., E-mail:


    Mesangial cells originate from the metanephric mesenchyme and maintain structural integrity of the glomerular microvascular bed and mesangial matrix homeostasis. In response to metabolic, immunologic or hemodynamic injury, these cells undergo apoptosis or acquire an activated phenotype and undergo hypertrophy, proliferation with excessive production of matrix proteins, growth factors, chemokines and cytokines. These soluble factors exert autocrine and paracrine effects on the cells or on other glomerular cells, respectively. MCs are primary targets of immune-mediated glomerular diseases such as IGA nephropathy or metabolic diseases such as diabetes. MCs may also respond to injury that primarily involves podocytes and endothelial cells or to structural and genetic abnormalities of the glomerular basement membrane. Signal transduction and oxidant stress pathways are activated in MCs and likely represent integrated input from multiple mediators. Such responses are convenient targets for therapeutic intervention. Studies in cultured MCs should be supplemented with in vivo studies as well as examination of freshly isolated cells from normal and diseases glomeruli. In addition to ex vivo morphologic studies in kidney cortex, cells should be studied in their natural environment, isolated glomeruli or even tissue slices. Identification of a specific marker of MCs should help genetic manipulation as well as selective therapeutic targeting of these cells. Identification of biological responses of MCs that are not mediated by the renin–angiotensin system should help development of novel and effective therapeutic strategies to treat diseases characterized by MC pathology.

  18. Biological rhythms and preeclampsia

    Directory of Open Access Journals (Sweden)

    Agnès eDitisheim


    Full Text Available The impact of impaired circadian rhythm on health has been widely studied in shift workers and trans-meridian travelers. A part from its correlation with sleep and mood disorders, biological rhythm impairment is a recognized risk factor for cardiovascular diseases and breast cancer.Preeclampsia is a major public health issue, associated with a significant maternal and fetal morbidity and mortality worldwide. While the risks factors for this condition such as obesity, diabetes, pre-existing hypertension have been identified, the underlying mechanism of this multi-factorial disease is yet not fully understood.The disruption of the light/dark cycle in pregnancy has been associated with adverse outcomes. Slightly increased risk for small for gestational age babies, low birth weight babies and preterm deliveries has been reported in shift working women. Whether altered circadian cycle represents a risk factor for preeclampsia or preeclampsia is itself linked with an abnormal circadian cycle is less clear. There are only few reports available, showing conflicting results. In this review, we will discuss recent observations concerning circadian pattern of blood pressure in normotensive and hypertensive pregnancies. We explore the hypothesis that circadian misalignments may represent a risk factor for preeclampsia. Unraveling potential link between circadian clock gene and preeclampsia could offer a novel approach to our understanding of this multi-system disease specific to pregnancy.

  19. Biological control of ticks (United States)

    Samish, M.; Ginsberg, H.; Glazer, I.; Bowman, A.S.; Nuttall, P.


    Ticks have numerous natural enemies, but only a few species have been evaluated as tick biocontrol agents (BCAs). Some laboratory results suggest that several bacteria are pathogenic to ticks, but their mode of action and their potential value as biocontrol agents remain to be determined. The most promising entomopathogenic fungi appear to be Metarhizium anisopliae and Beauveria bassiana, strains of which are already commercially available for the control of some pests. Development of effective formulations is critical for tick management. Entomopathogenic nematodes that are pathogenic to ticks can potentially control ticks, but improved formulations and selection of novel nematode strains are needed. Parasitoid wasps of the genus Ixodiphagus do not typically control ticks under natural conditions, but inundative releases show potential value. Most predators of ticks are generalists, with a limited potential for tick management (one possible exception is oxpeckers in Africa). Biological control is likely to play a substantial role in future IPM programmes for ticks because of the diversity of taxa that show high potential as tick BCAs. Considerable research is required to select appropriate strains, develop them as BCAs, establish their effectiveness, and devise production strategies to bring them to practical use.

  20. Aristotle's biopolitics: a defense of biological teleology against biological nihilism. (United States)

    Arnhart, L


    Modern Darwinian biology seems to promote nihilism, for it seems to teach that there is no rationally discoverable standard in nature for giving meaning to life. The purpose of this article is to argue for a revival of Aristotle's biological teleology as a reasonable alternative to biological nihilism. The article begins with Edward Wilson's vain struggle against nihilism. Then it is argued that a teleological understanding of nature is assumed in the practice of medicine, as illustrated by one case from Oliver Sacks' neurological practice. The article then considers the importance of biological teleology for Aristotle's moral and political philosophy, and attention is given to some points of agreement and disagreement with contemporary sociobiologists. The main part of the article is then devoted to a defense of Aristotle's biology against the five objections that might be made by a Darwinian biologist. Finally, the article illustrates the practical implications of this issue for bioethics by considering the recent work of Engelhardt.

  1. Introduction to Biology, Tropical Edition. (United States)

    Mackean, D. G.

    This pupil's reference book is intended to provide biological information, using plants and animals which are suitable for study over a wide range of tropical countries. Its topics are taken mostly from the biology syllabi for the British General Certification of Education at the Ordinary Level and are written principally for pupils in the last…

  2. Biology and Water Pollution Control. (United States)

    Warren, Charles E.

    Within this text, the reader is attuned to the role biology can and should play in combating the alarming increase in water pollution. Both the urgency of the problem and the biological techniques that are being developed to cope with the water pollution crisis are scrutinized; what is and is not known about the problem is explained; past,…

  3. Space Biology: Patterns of Life (United States)

    Salisbury, Frank B.


    Present knowledge about Mars is compared with past beliefs about the planet. Biological experiments that indicate life may exist on Mars are interpreted. Life patterns or biological features that might be postulated for extraterrestrial life are presented at the molecular, cellular, organism, and ecosystem levels. (DS)

  4. Marine Biology and Human Affairs (United States)

    Russell, F. S.


    Marine biology has become an important area for study throughout the world. The author of this article discusses some of the important discoveries and fields of research in marine biology that are useful for mankind. Topics include food from the sea, fish farming, pesticides, pollution, and conservation. (MA)

  5. Querying Large Biological Network Datasets (United States)

    Gulsoy, Gunhan


    New experimental methods has resulted in increasing amount of genetic interaction data to be generated every day. Biological networks are used to store genetic interaction data gathered. Increasing amount of data available requires fast large scale analysis methods. Therefore, we address the problem of querying large biological network datasets.…

  6. Validation of systems biology models

    NARCIS (Netherlands)

    Hasdemir, D.


    The paradigm shift from qualitative to quantitative analysis of biological systems brought a substantial number of modeling approaches to the stage of molecular biology research. These include but certainly are not limited to nonlinear kinetic models, static network models and models obtained by the

  7. Structural Biology Guides Antibiotic Discovery (United States)

    Polyak, Steven


    Modern drug discovery programs require the contribution of researchers in a number of specialist areas. One of these areas is structural biology. Using X-ray crystallography, the molecular basis of how a drug binds to its biological target and exerts its mode of action can be defined. For example, a drug that binds into the active site of an…

  8. Biological Effectiveness of Antiproton Annihilation

    DEFF Research Database (Denmark)

    Maggiore, C.; Agazaryan, N.; Bassler, N.;


    from the annihilation of antiprotons produce an increase in ‘‘biological dose’’ in the vicinity of the narrow Bragg peak for antiprotons compared to protons. This experiment is the first direct measurement of the biological effects of antiproton annihilation. The background, description, and status...

  9. Static Analysis for Systems Biology

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nielson, Hanne Riis; Rosa, D. Schuch da


    This paper shows how static analysis techniques can help understanding biological systems. Based on a simple example we illustrate the outcome of performing three different analyses extracting information of increasing precision. We conclude by reporting on the potential impact and exploitation o...... of these techniques in systems biology....

  10. Interfacing DNA nanodevices with biology

    DEFF Research Database (Denmark)

    Vinther, Mathias; Kjems, Jørgen


    in biology and biomedicine acting as a molecular ‘nanorobot’ or smart drug interacting with the cellular machinery. In this review, we will explore and examine the perspective of DNA nanotechnology for such use. We summarize which requirements DNA nanostructures must fulfil to function in cellular...... environments and inside living organisms. In addition, we highlight recent advances in interfacing DNA nanostructures with biology....

  11. From Biology to Quality (BQ)

    DEFF Research Database (Denmark)

    Nielsen, Michael Engelbrecht; Ingerslev, Hans-Christian


    “Quality is never an accident; it is always the result of high intention, sincere effort, intelligent direction and skilful execution; it represents the wise choice of many alternatives.” (William A. Foster) The quality of fish meat is dependent upon a wide range of biological and non-biological ...

  12. The Ethics of Synthetic Biology

    DEFF Research Database (Denmark)

    Christiansen, Andreas

    The dissertation analyses and discusses a number of ethical issues that have been raised in connection with the development of synthetic biology. Synthetic biology is a set of new techniques for DNA-level design and construction of living beings with useful properties. The dissertation especially...

  13. Biological clocks: riding the tides. (United States)

    de la Iglesia, Horacio O; Johnson, Carl Hirschie


    Animals with habitats in the intertidal zone often display biological rhythms that coordinate with both the tidal and the daily environmental cycles. Two recent studies show that the molecular components of the biological clocks mediating tidal rhythms are likely different from the phylogenetically conserved components that mediate circadian (daily) rhythms.

  14. BIological Psychology, Exercise, and Stress. (United States)

    Dishman, Rod K.


    Reviews theory and methods used by the field of biological psychology to study stress that have potential for understanding how behavioral and biological adaptations to the stress of exercise are integrated. The overview focuses on anxiety, depression, and physiological responsiveness to nonexercise stressors from the perspective of biological…

  15. Virtual Environments in Biology Teaching (United States)

    Mikropoulos, Tassos A.; Katsikis, Apostolos; Nikolou, Eugenia; Tsakalis, Panayiotis


    This article reports on the design, development and evaluation of an educational virtual environment for biology teaching. In particular it proposes a highly interactive three-dimensional synthetic environment involving certain learning tasks for the support of teaching plant cell biology and the process of photosynthesis. The environment has been…

  16. An Exercise in Biological Control. (United States)

    Lennox, John; Duke, Michael


    Discusses the history of the use of pesticides and biological control. Introduces the concept of biological control as illustrated in the use of the entomopathogenic bacterium Bacillus thuringiensis and highlights laboratory demonstrations of Koch's postulates. Includes an exercise that offers the student and teacher several integrated learning…

  17. Vitalism in Naive Biological Thinking. (United States)

    Morris, Suzanne C.; Taplin, John E.; Gelman, Susan A.


    Three experiments investigated use of vitalistic explanations for biological phenomena by 5- and 10-year-olds and by adults. Results replicated the original Japanese finding of vitalistic thinking among English-speaking 5-year-olds, identified the more active component of vitalism as a belief in the transfer of energy during biological processes,…

  18. Modification of PBDEs (BDE-15, BDE-47, BDE-85 and BDE-126) biological toxicity, bio-concentration, persistence and atmospheric long-range transport potential based on the pharmacophore modeling assistant with the full factor experimental design. (United States)

    Jiang, Long; Li, Yu


    In this study, the properties of AhR binding affinity, bio-concentration factor, half-life and vapor pressure were selected as the typical indicators of biological toxicity, bio-concentration, persistence and atmospheric long-range transport potential for polybrominated diphenyl ethers (PBDEs), respectively. A three-dimensional pharmacophore modeling assistant with a full factor experimental design for each property was used to reveal the significant pharmacophore features and the substituent effects to obtain reasonable modified schemes for the selected target PBDEs. Finally, the performances of the persistent organic pollutant (POP) properties, the synthesis feasibility and the fire resistance of the modified compounds were evaluated. The most influential pharmacophore feature for all POP properties was the hydrophobic group, especially the vinyl and propyl groups. Modified compounds with two additional hydrophobic groups exhibited a better regulatory performance. The average reduction in the proportions of the four POP properties for the modified compounds (except for 3-phenyl-BDE-15) was 70.60%, 52.44%, 47.04% and 70.88%. In addition, the energy and the C-Br bond dissociation enthalpy of the four typical PBDEs were higher than those of the modified compounds (except for 3-phenyl-BDE-15), indicating the synthesis feasibility and the lower energy barrier of the modified compounds to release Br free radicals to provide fire resistance.

  19. Meta-analysis of on-the-road experimental studies of hypnotics : effects of time after intake, dose, and half-life

    NARCIS (Netherlands)

    Roth, T; Eklov, S D; Drake, C L; Verster, J C


    BACKGROUND: The use of hypnotics is prevalent in the general population. Though these drugs have been shown to be effective, their residual effects may cause significant impairment to the user's driving ability. The objective of this meta-analysis is to determine whether there is a residual effect o

  20. Half-life systematics across the N=126 shell closure: role of first-forbidden transitions in the β decay of heavy neutron-rich nuclei. (United States)

    Morales, A I; Benlliure, J; Kurtukián-Nieto, T; Schmidt, K-H; Verma, S; Regan, P H; Podolyák, Z; Górska, M; Pietri, S; Kumar, R; Casarejos, E; Al-Dahan, N; Algora, A; Alkhomashi, N; Álvarez-Pol, H; Benzoni, G; Blazhev, A; Boutachkov, P; Bruce, A M; Cáceres, L S; Cullen, I J; Denis Bacelar, A M; Doornenbal, P; Estévez-Aguado, M E; Farrelly, G; Fujita, Y; Garnsworthy, A B; Gelletly, W; Gerl, J; Grebosz, J; Hoischen, R; Kojouharov, I; Kurz, N; Lalkovski, S; Liu, Z; Mihai, C; Molina, F; Mücher, D; Rubio, B; Shaffner, H; Steer, S J; Tamii, A; Tashenov, S; Valiente-Dobón, J J; Walker, P M; Wollersheim, H J; Woods, P J


    This Letter reports on a systematic study of β-decay half-lives of neutron-rich nuclei around doubly magic (208)Pb. The lifetimes of the 126-neutron shell isotone (204)Pt and the neighboring (200-202)Ir, (203)Pt, (204)Au are presented together with other 19 half-lives measured during the "stopped beam" campaign of the rare isotope investigations at GSI collaboration. The results constrain the main nuclear theories used in calculations of r-process nucleosynthesis. Predictions based on a statistical macroscopic description of the first-forbidden β strength reveal significant deviations for most of the nuclei with Nforbidden transitions reproduce more satisfactorily the trend in the measured half-lives for the nuclei in this region, where the r-process pathway passes through during β decay back to stability.

  1. Investigation of the Efficiencies of Bioaerosol Samplers for Collecting Aerosolized Bacteria Using a Fluorescent Tracer. II: Sampling Efficiency and Half-Life Time

    NARCIS (Netherlands)

    Zhao, Y.; Aarnink, A.J.A.; Doornenbal, P.; Huynh, T.T.T.; Groot Koerkamp, P.W.G.; Landman, W.J.M.; Jong, de M.C.M.


    Using uranine as a physical tracer, this study assessed the sampling efficiencies of four bioaerosol samplers (Andersen 6-stage impactor, all glass impinger “AGI-30,” OMNI-3000, and Airport MD8 with gelatin filter) for collecting Gram-positive bacteria (Enterococcus faecalis), Gram-negative bacteria

  2. Integrative analysis of mRNA expression and half-life data reveals trans-acting genetic variants associated with increased expression of stable transcripts.

    Directory of Open Access Journals (Sweden)

    Thong T Nguyen

    Full Text Available Genetic variation in gene expression makes an important contribution to phenotypic variation and susceptibility to disease. Recently, a subset of cis-acting expression quantitative loci (eQTLs has been found to result from polymorphisms that affect RNA stability. Here we carried out a search for trans-acting variants that influence RNA stability. We first demonstrate that differences in the activity of trans-acting factors that stabilize RNA can be detected by comparing the expression levels of long-lived (stable and short-lived (unstable transcripts in high-throughput gene expression experiments. Using gene expression microarray data generated from eight HapMap3 populations, we calculated the relative expression ranks of long-lived transcripts versus short-lived transcripts in each sample. Treating this as a quantitative trait, we applied genome-wide association and identified a single nucleotide polymorphism (SNP, rs6137010, on chromosome 20p13 with which it is strongly associated in two Asian populations (p = 4×10(-10 in CHB - Han Chinese from Beijing; p = 1×10(-4 in JPT - Japanese from Tokyo. This SNP is a cis-eQTL for SNRPB in CHB and JPT but not in the other six HapMap3 populations. SNRPB is a core component of the spliceosome, and has previously been shown to affect the expression of many RNA processing factors. We propose that a cis-eQTL of SNRPB may be directly responsible for inter-individual variation in relative expression of long-lived versus short-lived transcript in Asian populations. In support of this hypothesis, knockdown of SNRPB results in a significant reduction in the relative expression of long-lived versus short-lived transcripts. Samples with higher relative expression of long-lived transcripts also had higher relative expression of coding compared to non-coding RNA and of RNA from housekeeping compared to non-housekeeping genes, due to the lower decay rates of coding RNAs, particularly those that perform housekeeping functions, compared to non-coding RNAs.

  3. 医学期刊被引半衰期分析%An Analysis on Medical Journal Cited Half-life

    Institute of Scientific and Technical Information of China (English)

    戴丽琼; 毛文明; 姜美萍



  4. Half-life Model: the Scale of Kaizen%半生命周期--持续改进的标尺

    Institute of Scientific and Technical Information of China (English)

    郭春明; 韩之俊



  5. From J. J. Thomson to FAIR, what do we learn from Large-Scale Mass and Half-Life Measurements of Bare and Few-Electron Ions? (United States)

    Münzenberg, Gottfried; Geissel, Hans; Litvinov, Yuri A.


    This contribution is based on the combination of the talks: "What can we learn from large-scale mass measurements," "Present and future experiments with stored exotic nuclei at relativistic energies," and "Beta decay of highly-charged ions." Studying the nuclear mass surface gives information on the evolution of nuclear structure such as nuclear shells, the onset of deformation and the drip-lines. Previously, most of the masses far-off stability has been obtained from decay data. Modern methods allow direct mass measurements. They are much more sensitive, down to single atoms, access short-lived species and have high accuracy. Large-scale explorations of the nuclear mass surface are ideally performed with the combination of the in-flight FRagment Separator FRS and the Experimental Storage Ring ESR. After a brief historic introduction selected examples such as the evolution of shell closures far-off stability and the proton-neutron interaction will be discussed in the framework of our data. Recently, the experiments have been extended and led to the discovery of new heavy neutron-rich isotopes along with their mass and lifetime measurements. Storage rings applied at relativistic energies are a unique tool to study the radioactive decay of bare or few-electron atomic nuclei. New features observed with the analysis of stored circulating mother and daughter ions including oscillations in the decay curves of hydrogen-like nuclei will be addressed. Future experiments with NUSTAR at FAIR will further extend our knowledge to the borderlines of nuclear existence.

  6. Influência dos sucos de frutas sobre a biodisponibilidade e meia-vida dos medicamentos = Fruit juices influence in the bioavailability and half-life of drugs

    Directory of Open Access Journals (Sweden)

    Salvi, Rosane Maria


    Conclusão: O estudo evidenciou que interações entre sucos de laranja e toranja consistem nas ocorrências mais comumente citadas, muitas vezes responsáveis por variações sobre a biodisponibilidade e meia-vida de fármacos o que, em última instância, determina variações na resposta terapêutica

  7. Influência dos sucos de frutas sobre a biodisponibilidade e meia-vida dos medicamentos Influence of fruit juices on bioavailability and half-life of drugs

    Directory of Open Access Journals (Sweden)

    Carolina Mariante de Abreu


    Full Text Available Introdução: A administração de medicamentos juntamente com sucos de frutas pode determinar variações na farmacocinética e farmacodinâmica, comprometendo a biodisponibilidade e meia-vida dos compostos envolvidos. Objetivo: Verificar e classificar informações sobre ocorrências de interações que resultam da co-administração de medicamentos e sucos de frutas. Materiais e Métodos: Foi realizada uma revisão na literatura a cerca do tema proposto. Os dados sobre interações foram obtidos de pesquisa em diferentes bancos de dados e livros relacionados, realizada no período de 2008/2009. O método utilizado no estudo incluiu a análise de informações obtidas a partir de bases de dados como PUBMED, SCIELO, BDENF, BBO e natural medicine comprehensive database, sendo que os descritores utilizados consistiram em: interações, interactions, sucos de frutas, fruit juice, CYP 450, P-glicoproteínas e OATP (organic anion transporter polypeptide. Resultados: Ficou evidente a existência de um número significativo de interações, identificadas a partir de estudos experimentais, casos-controle e relatos de caso. Referências sobre agravamento de um efeito ou ineficácia terapêutica, decorrentes da associação de fármacos com sucos de frutas, foram citadas por diversos autores. Conclusão: O estudo evidenciou que interações entre sucos de laranja e toranja consistem nas ocorrências mais comumente citadas, muitas vezes responsáveis por variações sobre a biodisponibilidade e meia-vida de fármacos o que, em última instância, determina variações na resposta terapêutica.Administering medications together with fruit juices may lead to variations in pharmacokinetics and pharmacodynamics, with repercussions on the bioavailability and half –life of the compounds. Pharmacokinetic mechanisms are usually related to intestinal and hepatic enzymes of cytochrome P-450 (CYP 450 interference, as well as in transporter enzymes of the mucosa (P-glycoproteín, organic anion transporter polypeptide - OATP. Based on the data above, the aforementioned article seeks information on interaction events involving the co-administration of medications and fruit juices. The review was based on research performed in different databases and related books. The results showed a significant number of interactions, identified in experimental studies, cases-controls and case report. References to the potentiation of an effect, or to therapeutic inefficacy, as a result of the association of pharmaceuticals with fruit juice, were mentioned by several authors, which justify the relevance of diagnosing these phenomenon.

  8. Human FcRn can mediate the transport across intestinal mucosal barrier and prolong the half-life of rabbit IgG in vivo

    Directory of Open Access Journals (Sweden)

    Guangchang Pang


    Full Text Available FcRn (neonatal Fc receptor plays an important role in IgG transportation, antigen presentation and signal transmission. In this study, the complement fixation test and flow cytometry test were performed to verify whether the heterologous antibody could be transmitted to the serum or leukocyte with FcγR (Fc gamma receptor across the intestinal mucosa. The results showed that rabbit anti-bovine IgG could be detected in both the serum and the leukocytes, which indicated that the heterologous antibody could transport across the intestinal mucosa to enter the blood and be effectively delivered to the leukocytes with FcγR. In addition, the results also showed that the rabbit anti-bovine IgG still could be detected in the leukocyte group (P=0.044<0.05 after 21 days. It indicated that the rabbit IgG could exist in the body for a long term (up to 21 days after being transported to the cells containing FcγR.

  9. Life is a journey: source-path-goal structure in the videogames "Half-Life 2", "Heavy Rain", and "Grim Fandango"

    NARCIS (Netherlands)

    Kromhout, R.; Forceville, C.


    The debate between narrativists and ludologists has long enlivened discussions among game theorists. Should videogames be seen as an offshoot of (film) stories, and thus be studied primarily from the perspective of narratology? Or do they represent a truly different phenomenon, and thus require an a

  10. Synthetic biology and genetic causation. (United States)

    Oftedal, Gry; Parkkinen, Veli-Pekka


    Synthetic biology research is often described in terms of programming cells through the introduction of synthetic genes. Genetic material is seemingly attributed with a high level of causal responsibility. We discuss genetic causation in synthetic biology and distinguish three gene concepts differing in their assumptions of genetic control. We argue that synthetic biology generally employs a difference-making approach to establishing genetic causes, and that this approach does not commit to a specific notion of genetic program or genetic control. Still, we suggest that a strong program concept of genetic material can be used as a successful heuristic in certain areas of synthetic biology. Its application requires control of causal context, and may stand in need of a modular decomposition of the target system. We relate different modularity concepts to the discussion of genetic causation and point to possible advantages of and important limitations to seeking modularity in synthetic biology systems.

  11. Combining supramolecular chemistry with biology. (United States)

    Uhlenheuer, Dana A; Petkau, Katja; Brunsveld, Luc


    Supramolecular chemistry has primarily found its inspiration in biological molecules, such as proteins and lipids, and their interactions. Currently the supramolecular assembly of designed compounds can be controlled to great extent. This provides the opportunity to combine these synthetic supramolecular elements with biomolecules for the study of biological phenomena. This tutorial review focuses on the possibilities of the marriage of synthetic supramolecular architectures and biological systems. It highlights that synthetic supramolecular elements are for example ideal platforms for the recognition and modulation of proteins and cells. The unique features of synthetic supramolecular systems with control over size, shape, valency, and interaction strength allow the generation of structures fitting the demands to approach the biological problems at hand. Supramolecular chemistry has come full circle, studying the biology and its molecules which initially inspired its conception.

  12. Engineering life through Synthetic Biology. (United States)

    Chopra, Paras; Kamma, Akhil


    Synthetic Biology is a field involving synthesis of novel biological systems which are not generally found in nature. It has brought a new paradigm in science as it has enabled scientists to create life from the scratch, hence helping better understand the principles of biology. The viability of living organisms that use unnatural molecules is also being explored. Unconventional projects such as DNA playing tic-tac-toe, bacterial photographic film, etc. are taking biology to its extremes. The field holds a promise for mass production of cheap drugs and programming bacteria to seek-and-destroy tumors in the body. However, the complexity of biological systems make the field a challenging one. In addition to this, there are other major technical and ethical challenges which need to be addressed before the field realizes its true potential.

  13. Grand challenges for biological engineering. (United States)

    Yoon, Jeong-Yeol; Riley, Mark R


    Biological engineering will play a significant role in solving many of the world's problems in medicine, agriculture, and the environment. Recently the U.S. National Academy of Engineering (NAE) released a document "Grand Challenges in Engineering," covering broad realms of human concern from sustainability, health, vulnerability and the joy of living. Biological engineers, having tools and techniques at the interface between living and non-living entities, will play a prominent role in forging a better future. The 2010 Institute of Biological Engineering (IBE) conference in Cambridge, MA, USA will address, in part, the roles of biological engineering in solving the challenges presented by the NAE. This letter presents a brief outline of how biological engineers are working to solve these large scale and integrated problems of our society.

  14. Grand challenges for biological engineering

    Directory of Open Access Journals (Sweden)

    Riley Mark R


    Full Text Available Abstract Biological engineering will play a significant role in solving many of the world's problems in medicine, agriculture, and the environment. Recently the U.S. National Academy of Engineering (NAE released a document "Grand Challenges in Engineering," covering broad realms of human concern from sustainability, health, vulnerability and the joy of living. Biological engineers, having tools and techniques at the interface between living and non-living entities, will play a prominent role in forging a better future. The 2010 Institute of Biological Engineering (IBE conference in Cambridge, MA, USA will address, in part, the roles of biological engineering in solving the challenges presented by the NAE. This letter presents a brief outline of how biological engineers are working to solve these large scale and integrated problems of our society.

  15. Hierarchical structure of biological systems (United States)

    Alcocer-Cuarón, Carlos; Rivera, Ana L; Castaño, Victor M


    A general theory of biological systems, based on few fundamental propositions, allows a generalization of both Wierner and Berthalanffy approaches to theoretical biology. Here, a biological system is defined as a set of self-organized, differentiated elements that interact pair-wise through various networks and media, isolated from other sets by boundaries. Their relation to other systems can be described as a closed loop in a steady-state, which leads to a hierarchical structure and functioning of the biological system. Our thermodynamical approach of hierarchical character can be applied to biological systems of varying sizes through some general principles, based on the exchange of energy information and/or mass from and within the systems. PMID:24145961

  16. Loop Quantum Theory Applied to Biology and Nonlinear Whole Biology

    CERN Document Server

    Chang, Yi-Fang


    The loop quantum theory, which constitutes a very small discontinuous space, as new method is applied to biology. The model of protein folding and lungs is proposed. In the model, some known results are used, and four approximate conclusions are obtained: their structures are quantized, their space regions are finite, various singularities correspond to folding and crossed points, and different types of catastrophe exist. Further, based on the inseparability and correlativity of the biological systems, the nonlinear whole biology is proposed, and four basic hypotheses are formed. It may unify reductionism and holism, structuralism and functionalism. Finally, the medical meaning of the theory is discussed briefly.

  17. Biology and Economics: Metaphors that Economists usually take from Biology

    Directory of Open Access Journals (Sweden)

    Danny García Callejas


    Full Text Available Adam Smith, Alfred Marshall, Stanley Jevons, Karl Marx, Francois Quesnay and Joseph Schumpeter all have at least one thing in common: they used biological metaphors when speaking about economics. Nonetheless, today, this relation subsists and biology and economics are viewed as complementary sciences that have a lot to gain from joint research in fields like: evolutionary economics, economic growth, cognitive economics and environmental and ecological economics, among others. This paper, divided in four sections, will show this conclusion and explain that biology and economics are more sisters than strangers

  18. Biological Systems, Energy Sources, and Biology Teaching. Biology and Human Welfare. (United States)

    Tribe, Michael; Pritchard, Alan J.

    This five-chapter document (part of a series on biology and human welfare) focuses on biological systems as energy sources and on the teaching of this subject area. Chapter 1 discusses various topics related to energy and ecology, including biomass, photosynthesis and world energy balances, energy flow through ecosystems, and others. Chapter 2…

  19. Biological modulation of tectonics (United States)

    Sleep, N. H.; Bird, D. K.


    Photosynthesis has had geologic consequences over the Earth's history. In addition to modifying Earth's atmosphere and ocean chemistry, it has also modulated tectonic processes through enhanced weathering and modification of the nature and composition of sedimentary rocks within fold mountain belts and convergent margins. Molecular biological studies indicate that bacterial photosynthesis evolved just once and that most bacterial clades descend from this photosynthetic common ancestor. Iron-based photosynthesis (ideally 4FeO + CO2 + H2O = 2Fe2O3 + CH2O) was the most bountiful anoxygenic niche on land. The back reaction provided energy to heterotrophic microbes and returned FeO to the photosynthetic microbes. Bacterial land colonists evolved into ecosystems that effectively weathered FeO-bearing minerals and volcanic glass. Clays, sands, and dissolved cations from the weathering process entered the ocean and formed our familiar classes sedimentary rocks: shales, sandstones, and carbonates. Marine photosynthesis caused organic carbon to accumulate in black shales. In contrast, non-photosynthetic ecosystems do not cause organic carbon to accumulate in shale. These evolutionary events occurred before 3.8 Ga as black shales are among the oldest rock types (Rosing and Frei, Earth Planet. Sci. Lett. 217, 237-244, 2004). Thick sedimentary sequences deformed into fold mountain belts. They remelted at depth to form granitic rocks (Rosing et al., Palaeoclimatol. Palaeoecol. 232, 99-11, 2006). Regions of outcropping low-FeO rocks including granites, quartzites, and some shales were a direct result. This dearth of FeO favored the evolution of oxic photosynthesis of cyanobacteria from photosynthetic soil bacteria. Black shales have an additional modulation effect on tectonics as they concentrate radioactive elements, particularly uranium (e.g. so that the surface heat flow varies by a factor of ca. 2). Thick sequences of black shales at continental rises of passive margins are

  20. The Relationships between Epistemic Beliefs in Biology and Approaches to Learning Biology among Biology-Major University Students in Taiwan (United States)

    Lin, Yi-Chun; Liang, Jyh-Chong; Tsai, Chin-Chung


    The aim of this study was to investigate the relationships between students' epistemic beliefs in biology and their approaches to learning biology. To this end, two instruments, the epistemic beliefs in biology and the approaches to learning biology surveys, were developed and administered to 520 university biology students, respectively. By and…

  1. The meaning of biological information. (United States)

    Koonin, Eugene V


    Biological information encoded in genomes is fundamentally different from and effectively orthogonal to Shannon entropy. The biologically relevant concept of information has to do with 'meaning', i.e. encoding various biological functions with various degree of evolutionary conservation. Apart from direct experimentation, the meaning, or biological information content, can be extracted and quantified from alignments of homologous nucleotide or amino acid sequences but generally not from a single sequence, using appropriately modified information theoretical formulae. For short, information encoded in genomes is defined vertically but not horizontally. Informally but substantially, biological information density seems to be equivalent to 'meaning' of genomic sequences that spans the entire range from sharply defined, universal meaning to effective meaninglessness. Large fractions of genomes, up to 90% in some plants, belong within the domain of fuzzy meaning. The sequences with fuzzy meaning can be recruited for various functions, with the meaning subsequently fixed, and also could perform generic functional roles that do not require sequence conservation. Biological meaning is continuously transferred between the genomes of selfish elements and hosts in the process of their coevolution. Thus, in order to adequately describe genome function and evolution, the concepts of information theory have to be adapted to incorporate the notion of meaning that is central to biology.

  2. Digital 'faces' of synthetic biology. (United States)

    Friedrich, Kathrin


    In silicio design plays a fundamental role in the endeavour to synthesise biological systems. In particular, computer-aided design software enables users to manage the complexity of biological entities that is connected to their construction and reconfiguration. The software's graphical user interface bridges the gap between the machine-readable data on the algorithmic subface of the computer and its human-amenable surface represented by standardised diagrammatic elements. Notations like the Systems Biology Graphical Notation (SBGN), together with interactive operations such as drag & drop, allow the user to visually design and simulate synthetic systems as 'bio-algorithmic signs'. Finally, the digital programming process should be extended to the wet lab to manufacture the designed synthetic biological systems. By exploring the different 'faces' of synthetic biology, I argue that in particular computer-aided design (CAD) is pushing the idea to automatically produce de novo objects. Multifaceted software processes serve mutually aesthetic, epistemic and performative purposes by simultaneously black-boxing and bridging different data sources, experimental operations and community-wide standards. So far, synthetic biology is mainly a product of digital media technologies that structurally mimic the epistemological challenge to take both qualitative as well as quantitative aspects of biological systems into account in order to understand and produce new and functional entities.

  3. Synthetic biology and metabolic engineering. (United States)

    Stephanopoulos, Gregory


    Metabolic engineering emerged 20 years ago as the discipline occupied with the directed modification of metabolic pathways for the microbial synthesis of various products. As such, it deals with the engineering (design, construction, and optimization) of native as well as non-natural routes of product synthesis, aided in this task by the availability of synthetic DNA, the core enabling technology of synthetic biology. The two fields, however, only partially overlap in their interest in pathway engineering. While fabrication of biobricks, synthetic cells, genetic circuits, and nonlinear cell dynamics, along with pathway engineering, have occupied researchers in the field of synthetic biology, the sum total of these areas does not constitute a coherent definition of synthetic biology with a distinct intellectual foundation and well-defined areas of application. This paper reviews the origins of the two fields and advances two distinct paradigms for each of them: that of unit operations for metabolic engineering and electronic circuits for synthetic biology. In this context, metabolic engineering is about engineering cell factories for the biological manufacturing of chemical and pharmaceutical products, whereas the main focus of synthetic biology is fundamental biological research facilitated by the use of synthetic DNA and genetic circuits.

  4. Synthetic biology as red herring. (United States)

    Preston, Beth


    It has become commonplace to say that with the advent of technologies like synthetic biology the line between artifacts and living organisms, policed by metaphysicians since antiquity, is beginning to blur. But that line began to blur 10,000 years ago when plants and animals were first domesticated; and has been thoroughly blurred at least since agriculture became the dominant human subsistence pattern many millennia ago. Synthetic biology is ultimately only a late and unexceptional offshoot of this prehistoric development. From this perspective, then, synthetic biology is a red herring, distracting us from more thorough philosophical consideration of the most truly revolutionary human practice-agriculture. In the first section of this paper I will make this case with regard to ontology, arguing that synthetic biology crosses no ontological lines that were not crossed already in the Neolithic. In the second section I will construct a parallel case with regard to cognition, arguing that synthetic biology as biological engineering represents no cognitive advance over what was required for domestication and the new agricultural subsistence pattern it grounds. In the final section I will make the case with regard to human existence, arguing that synthetic biology, even if wildly successful, is not in a position to cause significant existential change in what it is to be human over and above the massive existential change caused by the transition to agriculture. I conclude that a longer historical perspective casts new light on some important issues in philosophy of technology and environmental philosophy.

  5. Fostering synergy between cell biology and systems biology. (United States)

    Eddy, James A; Funk, Cory C; Price, Nathan D


    In the shared pursuit of elucidating detailed mechanisms of cell function, systems biology presents a natural complement to ongoing efforts in cell biology. Systems biology aims to characterize biological systems through integrated and quantitative modeling of cellular information. The process of model building and analysis provides value through synthesizing and cataloging information about cells and molecules, predicting mechanisms and identifying generalizable themes, generating hypotheses and guiding experimental design, and highlighting knowledge gaps and refining understanding. In turn, incorporating domain expertise and experimental data is crucial for building towards whole cell models. An iterative cycle of interaction between cell and systems biologists advances the goals of both fields and establishes a framework for mechanistic understanding of the genome-to-phenome relationship.

  6. Agroterrorism, Biological Crimes, and Biological Warfare Targeting Animal Agriculture

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Terry M.; Logan-Henfrey, Linda; Weller, Richard E.; Kellman, Brian


    There is a rising level of concern that agriculture might be targeted for economic sabotage by terrorists. Knowledge gathered about the Soviet Union biological weapons program and Iraq following the Gulf War, confirmed that animals and agricultural crops were targets of bioweapon development. These revelations are particularly disturbing in light of the fact that both countries are States Parties to the Biological and Toxin Weapons Convention that entered into force in 1975. The potential for misusing biotechnology to create more virulent pathogens and the lack of international means to detect unethical uses of new technologies to create destructive bioweapons is of increasing concern. Disease outbreaks, whether naturally occurring or intentionally, involving agricultural pathogens that destroy livestock and crops would have a profound impact on a country's infrastructure, economy and export markets. This chapter deals with the history of agroterrorism, biological crimes and biological warfare directed toward animal agriculture, specifically, horses, cattle, swine, sheep, goats, and poultry.

  7. Marine molecular biology: An emerging field of biological sciences

    Digital Repository Service at National Institute of Oceanography (India)

    Thakur, N.L.; Jain, R.; Natalio, F.; Hamer, B.; Thakur, A.N.; Muller, W.E.G.

    to tackle problems associated with global climate changes, bio- diversity, environmental quality and use of marine living re- sources (Molecular biology in marine science, 1994). Marine biologists study oceanic life in relation to marine environment... that often range from small to global scale, whereas, molecular biologist study biological events in terms of the physiochemical properties of molecules. The immediate benefits of the collab- orative research between these two disciplines could include...

  8. Biological Databases for Human Research

    Institute of Scientific and Technical Information of China (English)

    Dong Zou; Lina Ma; Jun Yu; Zhang Zhang


    The completion of the Human Genome Project lays a foundation for systematically studying the human genome from evolutionary history to precision medicine against diseases. With the explosive growth of biological data, there is an increasing number of biological databases that have been developed in aid of human-related research. Here we present a collection of human-related biological databases and provide a mini-review by classifying them into different categories according to their data types. As human-related databases continue to grow not only in count but also in volume, challenges are ahead in big data storage, processing, exchange and curation.

  9. The Ethics of Synthetic Biology

    DEFF Research Database (Denmark)

    Christiansen, Andreas

    The dissertation analyses and discusses a number of ethical issues that have been raised in connection with the development of synthetic biology. Synthetic biology is a set of new techniques for DNA-level design and construction of living beings with useful properties. The dissertation especially......) popular responsesto them succeed, and whether the objections are ultimately persuasive.2. Given that synthetic biology is a new technology, there is a certain degree of uncertainty about its ultimate effects, and many perceive the technology as risky. I discuss two common approaches in risk regulation...

  10. Bilingual teaching of molecular biology

    Institute of Scientific and Technical Information of China (English)


    Recently bilingual teaching in China's universities has been widely carried out and become a popular subject for study. In this paper, the reasons for bilingual teaching of molecular biology are pointed out, the textbook of molecular biology and teaching method in bilingual teaching classes are determined after investigation and the practice of bilingually teaching molecular biology use both English and Chinese in a class. The effect has proved good. The bilingual teaching methods, the problem of bilingual teaching, the importance of understanding its significance and the possibilities of improving such teaching of the subject are also discussed.

  11. The renaissance of developmental biology. (United States)

    St Johnston, Daniel


    Since its heyday in the 1980s and 90s, the field of developmental biology has gone into decline; in part because it has been eclipsed by the rise of genomics and stem cell biology, and in part because it has seemed less pertinent in an era with so much focus on translational impact. In this essay, I argue that recent progress in genome-wide analyses and stem cell research, coupled with technological advances in imaging and genome editing, have created the conditions for the renaissance of a new wave of developmental biology with greater translational relevance.

  12. Ten questions about systems biology

    DEFF Research Database (Denmark)

    Joyner, Michael J; Pedersen, Bente K


    to understand how whole animals adapt to the real world. We argue that a lack of fluency in these concepts is a major stumbling block for what has been narrowly defined as 'systems biology' by some of its leading advocates. We also point out that it is a failure of regulation at multiple levels that causes many......In this paper we raise 'ten questions' broadly related to 'omics', the term systems biology, and why the new biology has failed to deliver major therapeutic advances for many common diseases, especially diabetes and cardiovascular disease. We argue that a fundamentally narrow and reductionist...

  13. Basic radiotherapy physics and biology

    CERN Document Server

    Chang, David S; Das, Indra J; Mendonca, Marc S; Dynlacht, Joseph R


    This book is a concise and well-illustrated review of the physics and biology of radiation therapy intended for radiation oncology residents, radiation therapists, dosimetrists, and physicists. It presents topics that are included on the Radiation Therapy Physics and Biology examinations and is designed with the intent of presenting information in an easily digestible format with maximum retention in mind. The inclusion of mnemonics, rules of thumb, and reader-friendly illustrations throughout the book help to make difficult concepts easier to grasp. Basic Radiotherapy Physics and Biology is a

  14. Biological Optimisation for Nurse Scheduling

    CERN Document Server

    Twycross, Jamie


    Artificial immune systems (AISs) to date have generally been inspired by naive biological metaphors. This has limited the effectiveness of these systems. In this position paper two ways in which AISs could be made more biologically realistic are discussed. We propose that AISs should draw their inspiration from organisms which possess only innate immune systems, and that AISs should employ systemic models of the immune system to structure their overall design. An outline of plant and invertebrate immune systems is presented, and a number of contemporary research that more biologically-realistic AISs could have is also discussed.

  15. Robust design of biological circuits: evolutionary systems biology approach. (United States)

    Chen, Bor-Sen; Hsu, Chih-Yuan; Liou, Jing-Jia


    Artificial gene circuits have been proposed to be embedded into microbial cells that function as switches, timers, oscillators, and the Boolean logic gates. Building more complex systems from these basic gene circuit components is one key advance for biologic circuit design and synthetic biology. However, the behavior of bioengineered gene circuits remains unstable and uncertain. In this study, a nonlinear stochastic system is proposed to model the biological systems with intrinsic parameter fluctuations and environmental molecular noise from the cellular context in the host cell. Based on evolutionary systems biology algorithm, the design parameters of target gene circuits can evolve to specific values in order to robustly track a desired biologic function in spite of intrinsic and environmental noise. The fitness function is selected to be inversely proportional to the tracking error so that the evolutionary biological circuit can achieve the optimal tracking mimicking the evolutionary process of a gene circuit. Finally, several design examples are given in silico with the Monte Carlo simulation to illustrate the design procedure and to confirm the robust performance of the proposed design method. The result shows that the designed gene circuits can robustly track desired behaviors with minimal errors even with nontrivial intrinsic and external noise.

  16. Systems biology of human atherosclerosis. (United States)

    Shalhoub, Joseph; Sikkel, Markus B; Davies, Kerry J; Vorkas, Panagiotis A; Want, Elizabeth J; Davies, Alun H


    Systems biology describes a holistic and integrative approach to understand physiology and pathology. The "omic" disciplines include genomics, transcriptomics, proteomics, and metabolic profiling (metabonomics and metabolomics). By adopting a stance, which is opposing (yet complimentary) to conventional research techniques, systems biology offers an overview by assessing the "net" biological effect imposed by a disease or nondisease state. There are a number of different organizational levels to be understood, from DNA to protein, metabolites, cells, organs and organisms, even beyond this to an organism's context. Systems biology relies on the existence of "nodes" and "edges." Nodes are the constituent part of the system being studied (eg, proteins in the proteome), while the edges are the way these constituents interact. In future, it will be increasingly important to collaborate, collating data from multiple studies to improve data sets, making them freely available and undertaking integrative analyses.

  17. VT Biodiversity Project - Biological Hotspots (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This dataset is the result of an effort to map biological "hotspots" in Vermont based on the "element occurrences" in the Nongame and Natural...

  18. Quivira NWR biological baseline data (United States)

    US Fish and Wildlife Service, Department of the Interior — This dataset is biological baseline data for Quivira National Wildlife Refuge as of January 2016. It contains data on species found on the refuge, when and where...

  19. Sex and the Biology Teacher (United States)

    Keller, Dolores Elaine


    Summarizes evidence that mammals are basically female, with masculine characteristics being imposed by hormonal changes in embryos or post-natally. Advocates the removal of male-dominant terminology in biological research and teaching. (AL)

  20. Synthetic Biology for Specialty Chemicals. (United States)

    Markham, Kelly A; Alper, Hal S


    In this review, we address recent advances in the field of synthetic biology and describe how those tools have been applied to produce a wide variety of chemicals in microorganisms. Here we classify the expansion of the synthetic biology toolbox into three different categories based on their primary function in strain engineering-for design, for construction, and for optimization. Next, focusing on recent years, we look at how chemicals have been produced using these new synthetic biology tools. Advances in producing fuels are briefly described, followed by a more thorough treatment of commodity chemicals, specialty chemicals, pharmaceuticals, and nutraceuticals. Throughout this review, an emphasis is placed on how synthetic biology tools are applied to strain engineering. Finally, we discuss organism and host strain diversity and provide a future outlook in the field.

  1. Systems biology and cardiac arrhythmias. (United States)

    Grace, Andrew A; Roden, Dan M


    During the past few years, the development of effective, empirical technologies for treatment of cardiac arrhythmias has exceeded the pace at which detailed knowledge of the underlying biology has accumulated. As a result, although some clinical arrhythmias can be cured with techniques such as catheter ablation, drug treatment and prediction of the risk of sudden death remain fairly primitive. The identification of key candidate genes for monogenic arrhythmia syndromes shows that to bring basic biology to the clinic is a powerful approach. Increasingly sophisticated experimental models and methods of measurement, including stem cell-based models of human cardiac arrhythmias, are being deployed to study how perturbations in several biologic pathways can result in an arrhythmia-prone heart. The biology of arrhythmia is largely quantifiable, which allows for systematic analysis that could transform treatment strategies that are often still empirical into management based on molecular evidence.

  2. Aging and computational systems biology. (United States)

    Mooney, Kathleen M; Morgan, Amy E; Mc Auley, Mark T


    Aging research is undergoing a paradigm shift, which has led to new and innovative methods of exploring this complex phenomenon. The systems biology approach endeavors to understand biological systems in a holistic manner, by taking account of intrinsic interactions, while also attempting to account for the impact of external inputs, such as diet. A key technique employed in systems biology is computational modeling, which involves mathematically describing and simulating the dynamics of biological systems. Although a large number of computational models have been developed in recent years, these models have focused on various discrete components of the aging process, and to date no model has succeeded in completely representing the full scope of aging. Combining existing models or developing new models may help to address this need and in so doing could help achieve an improved understanding of the intrinsic mechanisms which underpin aging.

  3. Inference problems in structural biology

    DEFF Research Database (Denmark)

    Olsson, Simon

    The structure and dynamics of biological molecules are essential for their function. Consequently, a wealth of experimental techniques have been developed to study these features. However, while experiments yield detailed information about geometrical features of molecules, this information is of...

  4. The relativity of biological function. (United States)

    Laubichler, Manfred D; Stadler, Peter F; Prohaska, Sonja J; Nowick, Katja


    Function is a central concept in biological theories and explanations. Yet discussions about function are often based on a narrow understanding of biological systems and processes, such as idealized molecular systems or simple evolutionary, i.e., selective, dynamics. Conflicting conceptions of function continue to be used in the scientific literature to support certain claims, for instance about the fraction of "functional DNA" in the human genome. Here we argue that all biologically meaningful interpretations of function are necessarily context dependent. This implies that they derive their meaning as well as their range of applicability only within a specific theoretical and measurement context. We use this framework to shed light on the current debate about functional DNA and argue that without considering explicitly the theoretical and measurement contexts all attempts to integrate biological theories are prone to fail.

  5. Text mining for systems biology. (United States)

    Fluck, Juliane; Hofmann-Apitius, Martin


    Scientific communication in biomedicine is, by and large, still text based. Text mining technologies for the automated extraction of useful biomedical information from unstructured text that can be directly used for systems biology modelling have been substantially improved over the past few years. In this review, we underline the importance of named entity recognition and relationship extraction as fundamental approaches that are relevant to systems biology. Furthermore, we emphasize the role of publicly organized scientific benchmarking challenges that reflect the current status of text-mining technology and are important in moving the entire field forward. Given further interdisciplinary development of systems biology-orientated ontologies and training corpora, we expect a steadily increasing impact of text-mining technology on systems biology in the future.

  6. Language from a biological perspective

    Indian Academy of Sciences (India)

    Mohinish Shukla


    The faculty of language is unique to the human species. This implies that there are human-specific biological changes that lie at the basis of human language. However, it is not clear what the nature of such changes are, and how they could be shaped by evolution. In this paper, emphasis is laid on describing language in a Chomskyan manner, as a mental object. This serves as a standpoint to speculate about the biological basis of the emergence and evolution of language.

  7. Feller's Contributions to Mathematical Biology


    Baake, Ellen; Wakolbinger, Anton


    This is a review of William Feller's important contributions to mathematical biology. The seminal paper [Feller1951] "Diffusion processes in genetics" was particularly influential on the development of stochastic processes at the interface to evolutionary biology, and interesting ideas in this direction (including a first characterization of what is nowadays known as "Feller's branching diffusion") already shaped up in the paper [Feller 1939] (written in German) "The foundations of a probabis...

  8. How physics can inspire biology (United States)

    Kornyshev, Alexei


    In July 1997 Adrian Parsegian, a biophysicist at the National Institutes of Health in the US and a former president of the Biophysical Society, published an article in Physics Today in which he outlined his thoughts about the main obstacles to a happy marriage between physics and biology. Parsegian started his article with a joke about a physicist talking to his biology-trained friend.

  9. Biological Effects of Acoustic Cavitation (United States)


    rectified diffusion. 56 III. STABLE CAVITATION A. Introduction There are manv areas associated with the biological effects of ultrasound in which the...used said as cavitation indicators. Further, if clinical ultrasound systems are found to be inducing cavitation , either stable or transient, it will...O BIOLOGICAL EFFECTS OF ACOUSTIC CAVITATION by Lawrence A. Crum -- Physical Acoustics Research Laboratory Department of Physics and Astronomy ’ CTE

  10. Researchers Discover Plants Biological Clock

    Institute of Scientific and Technical Information of China (English)



    Scientists who created glow-in-the-dark plants by shooting up seedlingswith firefly DNA have identified the first biological clock gene in plants. Discovery of the timepiece gene, which controls such biological rhythmsas daily leaf movements and proe openings, flower-blooming schedules andphotosynthesis cycles, could lead to a host of applications in ornamental horti-culture, agriculture and even human health. Many researchers believe that

  11. Nanoscale technology in biological systems

    CERN Document Server

    Greco, Ralph S; Smith, R Lane


    Reviewing recent accomplishments in the field of nanobiology Nanoscale Technology in Biological Systems introduces the application of nanoscale matrices to human biology. It focuses on the applications of nanotechnology fabrication to biomedical devices and discusses new physical methods for cell isolation and manipulation and intracellular communication at the molecular level. It also explores the application of nanobiology to cardiovascular diseases, oncology, transplantation, and a range of related disciplines. This book build a strong background in nanotechnology and nanobiology ideal for

  12. US Competitiveness in Synthetic Biology. (United States)

    Gronvall, Gigi Kwik


    Synthetic biology is an emerging technical field that aims to make biology easier to engineer; the field has applications in strategically important sectors for the US economy. While the United States currently leads in synthetic biology R&D, other nations are heavily investing in order to boost their economies, which will inevitably diminish the US leadership position. This outcome is not entirely negative--additional investments will expand markets--but it is critical that the US government take steps to remain competitive: There are applications from which the US population and economy may benefit; there are specific applications with importance for national defense; and US technical leadership will ensure that US experts have a leading role in synthetic biology governance, regulation, and oversight. Measures to increase competitiveness in S&T generally are broadly applicable for synthetic biology and should be pursued. However, the US government will also need to take action on fundamental issues that will affect the field's development, such as countering anti-GMO (genetically modified organism) sentiments and anti-GMO legislation. The United States should maintain its regulatory approach so that it is the product that is regulated, not the method used to create a product. At the same time, the United States needs to ensure that the regulatory framework is updated so that synthetic biology products do not fall into regulatory gaps. Finally, the United States needs to pay close attention to how synthetic biology applications may be governed internationally, such as through the Nagoya Protocol of the Convention on Biological Diversity, so that beneficial applications may be realized.

  13. Issues in Biological Shape Modelling

    DEFF Research Database (Denmark)

    Hilger, Klaus Baggesen

    This talk reflects parts of the current research at informatics and Mathematical Modelling at the Technical University of Denmark within biological shape modelling. We illustrate a series of generalizations, modifications, and applications of the elements of constructing models of shape or appear......This talk reflects parts of the current research at informatics and Mathematical Modelling at the Technical University of Denmark within biological shape modelling. We illustrate a series of generalizations, modifications, and applications of the elements of constructing models of shape...

  14. US Competitiveness in Synthetic Biology (United States)


    Synthetic biology is an emerging technical field that aims to make biology easier to engineer; the field has applications in strategically important sectors for the US economy. While the United States currently leads in synthetic biology R&D, other nations are heavily investing in order to boost their economies, which will inevitably diminish the US leadership position. This outcome is not entirely negative—additional investments will expand markets—but it is critical that the US government take steps to remain competitive: There are applications from which the US population and economy may benefit; there are specific applications with importance for national defense; and US technical leadership will ensure that US experts have a leading role in synthetic biology governance, regulation, and oversight. Measures to increase competitiveness in S&T generally are broadly applicable for synthetic biology and should be pursued. However, the US government will also need to take action on fundamental issues that will affect the field's development, such as countering anti-GMO (genetically modified organism) sentiments and anti-GMO legislation. The United States should maintain its regulatory approach so that it is the product that is regulated, not the method used to create a product. At the same time, the United States needs to ensure that the regulatory framework is updated so that synthetic biology products do not fall into regulatory gaps. Finally, the United States needs to pay close attention to how synthetic biology applications may be governed internationally, such as through the Nagoya Protocol of the Convention on Biological Diversity, so that beneficial applications may be realized. PMID:26690379

  15. The aesthetics of chemical biology. (United States)

    Parsons, Glenn


    Scientists and philosophers have long reflected on the place of aesthetics in science. In this essay, I review these discussions, identifying work of relevance to chemistry and, in particular, to the field of chemical biology. Topics discussed include the role of aesthetics in scientific theory choice, the aesthetics of molecular images, the beauty-making features of molecules, and the relation between the aesthetics of chemical biology and the aesthetics of industrial design.

  16. Market study: Biological isolation garment (United States)


    The biological isolation garment was originally designed for Apollo astronauts to wear upon their return to earth from the moon to avoid the possibility of their contaminating the environment. The concept has been adapted for medical use to protect certain patients from environmental contamination and the risk of infection. The nature and size of the anticipated market are examined with certain findings and conclusions relative to clinical acceptability and potential commercial viability of the biological isolation garment.

  17. Biological Activities of Hydrazone Derivatives

    Directory of Open Access Journals (Sweden)

    S. Güniz Küçükgüzel


    Full Text Available There has been considerable interest in the development of novel compounds with anticonvulsant, antidepressant, analgesic, antiinflammatory, antiplatelet, antimalarial, antimicrobial, antimycobacterial, antitumoral, vasodilator, antiviral and antischistosomiasis activities. Hydrazones possessing an azometine -NHN=CH- proton constitute an important class of compounds for new drug development. Therefore, many researchers have synthesized these compounds as target structures and evaluated their biological activities. These observations have been guiding for the development of new hydrazones that possess varied biological activities.

  18. Biological markets explain human ultrasociality. (United States)

    Sheskin, Mark; Lambert, Stéphane; Baumard, Nicolas


    The evidence Gowdy & Krall (G&K) provide is more consistent with a biological markets explanation of human ultrasociality than a group selection explanation. Specifically, large-scale societies provide a better biological market for cooperation than do small-scale societies, allowing individuals to increase their fitness. Importantly, many of the quality-of-life costs G&K discuss (e.g., patriarchy) are not fitness costs.

  19. Biological atomism and cell theory. (United States)

    Nicholson, Daniel J


    Biological atomism postulates that all life is composed of elementary and indivisible vital units. The activity of a living organism is thus conceived as the result of the activities and interactions of its elementary constituents, each of which individually already exhibits all the attributes proper to life. This paper surveys some of the key episodes in the history of biological atomism, and situates cell theory within this tradition. The atomistic foundations of cell theory are subsequently dissected and discussed, together with the theory's conceptual development and eventual consolidation. This paper then examines the major criticisms that have been waged against cell theory, and argues that these too can be interpreted through the prism of biological atomism as attempts to relocate the true biological atom away from the cell to a level of organization above or below it. Overall, biological atomism provides a useful perspective through which to examine the history and philosophy of cell theory, and it also opens up a new way of thinking about the epistemic decomposition of living organisms that significantly departs from the physicochemical reductionism of mechanistic biology.

  20. Where Synthetic Biology Meets ET (United States)

    Rothschild, Lynn J.


    Synthetic biology - the design and construction of new biological parts and systems and the redesign of existing ones for useful purposes - has the potential to transform fields from pharmaceuticals to fuels. Our lab has focused on the potential of synthetic biology to revolutionize all three major parts of astrobiology: Where do we come from? Where are we going? and Are we alone? For the first and third, synthetic biology is allowing us to answer whether the evolutionary narrative that has played out on planet earth is likely to have been unique or universal. For example, in our lab we are re-evolving the biosynthetic pathways of amino acids in order to understand potential capabilities of an early organism with a limited repertoire of amino acids and developing techniques for the recovery of metals from spent electronics on other planetary bodies. And what about the limits for life? Can we create organisms that expand the envelope for life? In the future synthetic biology will play an increasing role in human activities both on earth, in fields as diverse as human health and the industrial production of novel bio-composites. Beyond earth, we will rely increasingly on biologically-provided life support, as we have throughout our evolutionary history. In order to do this, the field will build on two of the great contributions of astrobiology: studies of the origin of life and life in extreme environments.