Galactic S Stars: Investigations of Color, Motion, and Spectral Features

Known bright S stars, recognized as such by their enhanced s-process abundances and C/O ratio, are typically members of the asymptotic giant branch (AGB) or the red giant branch (RGB). Few modern digital spectra for these objects have been published, from which intermediate resolution spectral indices and classifications could be derived. For published S stars we find accurate positions using the Two-Micron All Sky Survey (2MASS), and use the FAST spectrograph of the Tillinghast reflector on Mt. Hopkins to obtain the spectra of 57 objects. We make available a digital S star spectral atlas consisting of 14 spectra of S stars with diverse spectral features. We define and derive basic spectral indices that can help distinguish S stars from late-type (M) giants and carbon stars. We convolve all our spectra with the SDSS bandpasses, and employ the resulting gri magnitudes together with 2MASS JHK mags to investigate S star colors. S stars have colors similar to carbon and M stars, and are therefore difficult to distinguish by color alone. Using near and mid-infrared colors from IRAS and AKARI, we identify some of the stars as intrinsic (AGB) or extrinsic (with abundances enhanced by past mass-transfer). We also use V band and 2MASS magnitudes to calculate a temperature index for stars in the sample. We analyze the proper motions and parallaxes of our sample stars to determine upper and lower limit absolute magnitudes and distances, and confirm that most are probably giants.Comment: 11 pages. Accepted for publication in ApJS July 19, 2011. Spectra available as http://hea-www.harvard.edu/~pgreen/SStarAtlas.ta

Carbon enrichment of the evolved stars in the Sagittarius dwarf spheroidal

We present spectra of 1142 colour-selected stars in the direction of the Sagittarius Dwarf Spheroidal (Sgr dSph) galaxy, of which 1058 were taken with VLT/FLAMES multi-object spectrograph and 84 were taken with the SAAO Radcliffe 1.9-m telescope grating spectrograph. Spectroscopic membership is confirmed (at >99% confidence) for 592 stars on the basis of their radial velocity, and spectral types are given. Very slow rotation is marginally detected around the galaxy's major axis. We identify five S stars and 23 carbon stars, of which all but four carbon stars are newly-determined and all but one (PQ Sgr) are likely Sgr dSph members. We examine the onset of carbon-richness in this metal-poor galaxy in the context of stellar models. We compare the stellar death rate (one star per 1000-1700 years) to known planetary nebula dynamical ages and find that the bulk population produce the observed (carbon-rich) planetary nebulae. We compute average lifetimes of S and carbon stars as 60-250 and 130-500 kyr, compared to a total thermal-pulsing asymptotic giant branch lifetime of 530-1330 kyr. We conclude by discussing the return of carbon-rich material to the ISM.Comment: 14 pages, 10 figures, accepted MNRA

BMP2 commitment to the osteogenic lineage involves activation of Runx2 by DLX3 and a homeodomain transcriptional network

Several homeodomain (HD) proteins are critical for skeletal patterning and respond directly to BMP2 as an early step in bone formation. RUNX2, the earliest transcription factor proven essential for commitment to osteoblastogenesis, is also expressed in response to BMP2. However, there is a gap in our knowledge of the regulatory cascade from BMP2 signaling to the onset of osteogenesis. Here we show that BMP2 induces DLX3, a homeodomain protein that activates Runx2 gene transcription. Small interfering RNA knockdown studies in osteoblasts validate that DLX3 is a potent regulator of Runx2. Furthermore in Runx2 null cells, DLX3 forced expression suffices to induce transcription of Runx2, osteocalcin, and alkaline phosphatase genes, thus defining DLX3 as an osteogenic regulator independent of RUNX2. Our studies further show regulation of the Runx2 gene by several homeodomain proteins: MSX2 and CDP/cut repress whereas DLX3 and DLX5 activate endogenous Runx2 expression and promoter activity in non-osseous cells and osteoblasts. These HD proteins exhibit distinct temporal expression profiles during osteoblast differentiation as well as selective association with Runx2 chromatin that is related to Runx2 transcriptional activity and recruitment of RNA polymerase II. Runx2 promoter mutagenesis shows that multiple HD elements control expression of Runx2 in relation to the stages of osteoblast maturation. Our studies establish mechanisms for commitment to the osteogenic lineage directly through BMP2 induction of HD proteins DLX3 and DLX5 that activate Runx2, thus delineating a transcriptional regulatory pathway mediating osteoblast differentiation. We propose that the three homeodomain proteins MSX2, DLX3, and DLX5 provide a key series of molecular switches that regulate expression of Runx2 throughout bone formation. <br/

Strategies to control odours in livestock facilities: a critical review

[EN] Los olores generados en instalaciones ganaderas constituyen uno de los temas más relevantes de calidad del aire de la ganadería intensiva de producción . La reducción de los episodios molestos relacionados con la exposición de olores por tanto, es esencial para una ganadería sostenible producción . En este estudio, se revisa críticamente el estado - del- arte en las técnicas de reducción de olores en alojamientos para el ganado . Los avances científicos en la última década se revisan y necesidades de investigación también se identifican . La naturaleza compleja de la ganadería y los olores es una parte crítica . Aqui, las estrategias de control de olores más relevantes se analizan en términos de los conocimientos actuales y las necesidades futuras . Las estrategias que se consideran son : estrategias nutricionales , aditivos para estiércol, construcción diseño, filtración de aire , tapas de estiércol, los sistemas de tratamiento del estiércol y cortavientos . Por último , la investigación futura necesita y se identifican las prioridades al establecer técnicas de mitigación . A pesar de los importantes avances recientes, todavía hay algunos desafíos para los científicos, los productores y los reguladores , en particular relacionados con la evaluación de campo de los olores . Por lo tanto , para controlar los olores del ganado de manera efectiva , el uso de técnicas de evaluación de campo estandarizados serán requeridos . además, que investigan los errores de medición y de modelo pueden ser útiles para comprender mejor las limitaciones de los métodos actuales , así como para identificar las prioridades de investigación .This work has been possible within the framework of the research project “Línea multidisciplinar para aplicación de las técnicas de la mecánica de fluidos computacional a modelación de movimiento de flujos ambientales (2614)” from Vicerrectorado de Investigación, Universidad Politécnica de Valencia, Spain.Úbeda Sánchez, Y.; López Jiménez, PA.; Nicolas, J.; Calvet Sanz, S. (2013). Strategies to control odours in livestock facilities: a critical review. Spanish Journal of Agricultural Research. 11(4):1004-1015. doi:10.5424/sjar/2013114-4180S10041015114Aguilar M, Abaigar A, Irujo E, Calvet S, Merino P, 2012. Performance of floating covers for slurry storage in Northern Spain. Paper No 0955. Proc. Int Conf Agric Eng CIGR-AgEng 2012. Valencia (Spain).Amon, M., Dobeic, M., Sneath, R. W., Phillips, V. R., Misselbrook, T. H., & Pain, B. F. (1997). A farm-scale study on the use of clinoptilolite zeolite and De-Odorase® for reducing odour and ammonia emissions from broiler houses. Bioresource Technology, 61(3), 229-237. doi:10.1016/s0960-8524(97)00005-9Banhazi, T., Hudson, N., Dunlop, M., Dyson, C., & Thomas, R. (2009). Development and testing of an evaluation procedure for commercial manure additive products. Biosystems Engineering, 103(3), 321-328. doi:10.1016/j.biosystemseng.2009.04.011Blanes-Vidal, V., Hansen, M. N., Adamsen, A. P. S., Feilberg, A., Petersen, S. O., & Jensen, B. B. (2009). Characterization of odor released during handling of swine slurry: Part I. Relationship between odorants and perceived odor concentrations. Atmospheric Environment, 43(18), 2997-3005. doi:10.1016/j.atmosenv.2008.10.016Blanes-Vidal, V., Hansen, M. N., & Sousa, P. (2009). Reduction of Odor and Odorant Emissions from Slurry Stores by Means of Straw Covers. Journal of Environment Quality, 38(4), 1518. doi:10.2134/jeq2008.0412Bottcher, R. W. (2001). An Environmental Nuisance: Odor Concentrated and Transported by Dust. Chemical Senses, 26(3), 327-331. doi:10.1093/chemse/26.3.327CEN, 2003. Air quality-determination of odour concentration by dynamic olfactometry. EN 13725. European Committee for Standardization (CEN). Brussels, Belgium.L. Chen, & S. J. Hoff. (2009). Mitigating Odors from Agricultural Facilities: A Review of Literature Concerning Biofilters. Applied Engineering in Agriculture, 25(5), 751-766. doi:10.13031/2013.28854C. J. Clanton, D. R. Schmidt, R. E. Nicolai, P. R. Goodrich, L. D. Jacobson, K. A. Janni, … J. A. Buckel. (1999). DYNAMIC OLFACTOMETRY VARIABILITY IN DETERMINING ODOR DILUTIONS-TO-THRESHOLD. Transactions of the ASAE, 42(4), 1103-1112. doi:10.13031/2013.13258Clark, O. G., Moehn, S., Edeogu, I., Price, J., & Leonard, J. (2005). Manipulation of Dietary Protein and Nonstarch Polysaccharide to Control Swine Manure Emissions. Journal of Environment Quality, 34(5), 1461. doi:10.2134/jeq2004.0434Filipy, J., Rumburg, B., Mount, G., Westberg, H., & Lamb, B. (2006). Identification and quantification of volatile organic compounds from a dairy. Atmospheric Environment, 40(8), 1480-1494. doi:10.1016/j.atmosenv.2005.10.048Gay SW, Schmidt DR, Clanton CJ, Janni KA, Jacobson LD, Weisberg S, 2003. Odor, total reduced sulfur, and ammonia emissions from animal housing facilities and manure storage units in Minnesota. Appl Eng Agric 19(3): 347-360.M. N. Hansen, P. Kai, & H. B. Møller. (2006). EFFECTS OF ANAEROBIC DIGESTION AND SEPARATION OF PIG SLURRY ON ODOR EMISSION. Applied Engineering in Agriculture, 22(1), 135-139. doi:10.13031/2013.20192Hayes, E. ., Leek, A. B. ., Curran, T. ., Dodd, V. ., Carton, O. ., Beattie, V. ., & O’Doherty, J. . (2004). The influence of diet crude protein level on odour and ammonia emissions from finishing pig houses. Bioresource Technology, 91(3), 309-315. doi:10.1016/s0960-8524(03)00184-6Hobbs, P. J., Pain, B. F., Kay, R. M., & Lee, P. A. (1996). Reduction of Odorous Compounds in Fresh Pig Slurry by Dietary Control of Crude Protein. Journal of the Science of Food and Agriculture, 71(4), 508-514. doi:10.1002/(sici)1097-0010(199608)71:43.0.co;2-0Hong, S., Lee, I., Hwang, H., Seo, I., Bitog, J., Kwon, K., … Chung, S. (2011). CFD modelling of livestock odour dispersion over complex terrain, part II: Dispersion modelling. Biosystems Engineering, 108(3), 265-279. doi:10.1016/j.biosystemseng.2010.12.008HUDSON, N., AYOKO, G., COLLMAN, G., GALLAGHER, E., DUNLOP, M., & DUPEROUZEL, D. (2008). Long-term assessment of efficacy of permeable pond covers for odour reduction. Bioresource Technology, 99(14), 6409-6418. doi:10.1016/j.biortech.2007.11.058A. Ikeguchi, G. Zhang, L. Okushima, & J. C. Bennetsen. (2003). WINDWARD WINDBREAK EFFECTS ON AIRFLOW IN AND AROUND A SCALE MODEL OF A NATURALLY VENTILATED PIG BARN. Transactions of the ASAE, 46(3). doi:10.13031/2013.13594ISO, 1995. Guide to the expression of uncertainty in measurement, 1st edition, International Organization for Standardization, Genève (Switzerland), pp: 1-101.P. Kai, B. Kaspers, & T. van Kempen. (2006). Modeling Sources of Gaseous Emissions in a Pig House with Recharge Pit. Transactions of the ASABE, 49(5), 1479-1485. doi:10.13031/2013.22040Kerr BJ, Ziemer CJ, Trabue SL, Crouse JD, Parkin TB, 2006. Manure composition of swine as affected by dietary protein and cellulose concentrations. J Anim Sci 84(6): 1584-1592.Le, P. D., Aarnink, A. J. A., Ogink, N. W. M., Becker, P. M., & Verstegen, M. W. A. (2005). Odour from animal production facilities: its relationship to diet. Nutrition Research Reviews, 18(1), 3-30. doi:10.1079/nrr200592Le, P. D., Aarnink, A. J. A., Jongbloed, A. W., Peet-Schwering, C. M. C. V. der, Ogink, N. W. M., & Verstegen, M. W. A. (2007). Effects of dietary crude protein level on odour from pig manure. animal, 1(05), 734. doi:10.1017/s1751731107710303Le, P. D., Aarnink, A. J. A., Jongbloed, A. W., van der Peet-Schwering, C. M. C., Ogink, N. W. M., & Verstegen, M. W. A. (2008). Interactive effects of dietary crude protein and fermentable carbohydrate levels on odour from pig manure. Livestock Science, 114(1), 48-61. doi:10.1016/j.livsci.2007.04.009LEEK, A., HAYES, E., CURRAN, T., CALLAN, J., BEATTIE, V., DODD, V., & ODOHERTY, J. (2007). The influence of manure composition on emissions of odour and ammonia from finishing pigs fed different concentrations of dietary crude protein. Bioresource Technology, 98(18), 3431-3439. doi:10.1016/j.biortech.2006.11.003Lin, X.-J., Barrington, S., Nicell, J., Choinière, D., & Vézina, A. (2006). Influence of windbreaks on livestock odour dispersion plume in the field. Agriculture, Ecosystems & Environment, 116(3-4), 263-272. doi:10.1016/j.agee.2006.02.014Lin, X.-J., Barrington, S., Nicell, J., Choinière, D., & King, S. (2007). Livestock Odour Dispersion as Affected by Natural Windbreaks. Water, Air, and Soil Pollution, 182(1-4), 263-273. doi:10.1007/s11270-007-9337-9Lin, X.-J., Barrington, S., Choinière, D., & Prasher, S. (2009). Effect of weather conditions on windbreak odour dispersion. Journal of Wind Engineering and Industrial Aerodynamics, 97(11-12), 487-496. doi:10.1016/j.jweia.2009.06.012Lynch, M. B., O’Shea, C. J., Sweeney, T., Callan, J. J., & O’Doherty, J. V. (2008). Effect of crude protein concentration and sugar-beet pulp on nutrient digestibility, nitrogen excretion, intestinal fermentation and manure ammonia and odour emissions from finisher pigs. animal, 2(3), 425-434. doi:10.1017/s1751731107001267Mackie RI, Stroot PG, Varel VH, 1998. Biochemical identification and biological origin of key odor components in livestock waste. J Anim Sci 76(5): 1331-1342.Mc Alpine, P. O., O’Shea, C. J., Varley, P. F., Solan, P., Curran, T., & O’Doherty, J. V. (2012). The effect of protease and nonstarch polysaccharide enzymes on manure odor and ammonia emissions from finisher pigs. Journal of Animal Science, 90(suppl_4), 369-371. doi:10.2527/jas.53948McCrory, D. F., & Hobbs, P. J. (2001). Additives to Reduce Ammonia and Odor Emissions from Livestock Wastes. Journal of Environment Quality, 30(2), 345. doi:10.2134/jeq2001.302345xR. W. Melse, & N. W. M. Ogink. (2005). AIR SCRUBBING TECHNIQUES FOR AMMONIA AND ODOR REDUCTION AT LIVESTOCK OPERATIONS: REVIEW OF ON-FARM RESEARCH IN THE NETHERLANDS. Transactions of the ASAE, 48(6), 2303-2313. doi:10.13031/2013.20094Melse, R. W., Ogink, N. W. M., & Rulkens, W. H. (2009). Air Treatment Techniques for Abatement of Emissions from Intensive Livestock Production. The Open Agriculture Journal, 3(1), 6-12. doi:10.2174/1874331500903010006Mol G, Ogink NWM, 2004. The effect of two ammonia-emission-reducing pig housing systems on odour emission. Water Sci Technol 50(4): 335-340.Mussio, P., Gnyp, A. ., & Henshaw, P. . (2001). A fluctuating plume dispersion model for the prediction of odour-impact frequencies from continuous stationary sources. Atmospheric Environment, 35(16), 2955-2962. doi:10.1016/s1352-2310(00)00419-2Nahm, K. H. (2002). Efficient Feed Nutrient Utilization to Reduce Pollutants in Poultry and Swine Manure. Critical Reviews in Environmental Science and Technology, 32(1), 1-16. doi:10.1080/10643380290813435Nahm, K. H. (2003). Current Pollution and Odor Control Technologies for Poultry Production. Avian and Poultry Biology Reviews, 14(4), 151-174. doi:10.3184/147020603783637472Ndegwa, P. M., Zhu, J., & Luo, A. (2002). SE—Structures and Environment. Biosystems Engineering, 81(1), 127-133. doi:10.1006/bioe.2001.0008Nicell, J. A. (2009). Assessment and regulation of odour impacts. Atmospheric Environment, 43(1), 196-206. doi:10.1016/j.atmosenv.2008.09.033Nicolas, J., Delva, J., Cobut, P., & Romain, A.-C. (2008). Development and validating procedure of a formula to calculate a minimum separation distance from piggeries and poultry facilities to sensitive receptors. Atmospheric Environment, 42(30), 7087-7095. doi:10.1016/j.atmosenv.2008.06.007O’Connell, J. M., Callan, J. J., & O’Doherty, J. V. (2006). The effect of dietary crude protein level, cereal type and exogenous enzyme supplementation on nutrient digestibility, nitrogen excretion, faecal volatile fatty acid concentration and ammonia emissions from pigs. Animal Feed Science and Technology, 127(1-2), 73-88. doi:10.1016/j.anifeedsci.2005.09.002O’Neill, D. H., & Phillips, V. R. (1991). A review of the control of odour nuisancefrom livestock buildings: Part 1, influence of the techniques for managing waste within the building. Journal of Agricultural Engineering Research, 50, 1-10. doi:10.1016/s0021-8634(05)80001-0O’Shea, C. J., Sweeney, T., Lynch, M. B., Callan, J. J., & O’Doherty, J. V. (2011). Modification of selected bacteria and markers of protein fermentation in the distal gastrointestinal tract of pigs upon consumption of chitosan is accompanied by heightened manure odor emissions1. Journal of Animal Science, 89(5), 1366-1375. doi:10.2527/jas.2010-2922Ogink NWM, Koerkamp PWGG, 2001. Comparison of odour emissions from animal housing systems with low ammonia emission. Water Sci Technol 44(9): 245-252.Otto ER, Yokoyama M, Hengemuehle S, von Bermuth RD, van Kempen T, Trottier NL, 2003. Ammonia, volatile fatty acids, phenolics, and odor offensiveness in manure from growing pigs fed diets reduced in protein concentration. J Anim Sci 81(7): 1754-1763.Powers WJ, 1999. Odor control for livestock systems. J Anim Sci 77: 169-176.Revah, S., & Morgan-Sagastume, J. M. (s. f.). Methods of Odor and VOC Control. Biotechnology for Odor and Air Pollution Control, 29-63. doi:10.1007/3-540-27007-8_3Schiffman SS, Williams CM, 2005. Science of odor as a potential health issue. J Environ Qual 34(1): 129-138.Schiffman, S. S., Bennett, J. L., & Raymer, J. H. (2001). Quantification of odors and odorants from swine operations in North Carolina. Agricultural and Forest Meteorology, 108(3), 213-240. doi:10.1016/s0168-1923(01)00239-8Seginer, I. (1975). Atmospheric-stability effect on windbreak shelter and drag. Boundary-Layer Meteorology, 8(3-4), 383-400. doi:10.1007/bf02153559Shusterman, D. (1999). The health significance of environmental odour pollution: revisited. Journal of Environmental Medicine, 1(4), 249-258. doi:10.1002/jem.38Smeets, M. A. M., Bulsing, P. J., van Rooden, S., Steinmann, R., de Ru, J. A., Ogink, N. W. M., … Dalton, P. H. (2006). Odor and Irritation Thresholds for Ammonia: A Comparison between Static and Dynamic Olfactometry. Chemical Senses, 32(1), 11-20. doi:10.1093/chemse/bjl031Smith E, Gordon R, Campbell A, Bourque CPA, 2007. An assessment of odour emissions from land applied swine manure. Can Biosyst Eng 49(6): 33-40.Smith, R. J. (1993). Dispersion of Odours From Ground Level Agricultural Sources. Journal of Agricultural Engineering Research, 54(3), 187-200. doi:10.1006/jaer.1993.1013Sutton AL, Kephart KB, Verstegen MWA, Canh TT, Hobbs PJ, 1999. Potential for reduction of odorous compounds in swine manure through diet modification. J Anim Sci 77(2): 430-439.Sykes, R. I., & Gabruk, R. S. (1997). A Second-Order Closure Model for the Effect of Averaging Time on Turbulent Plume Dispersion. Journal of Applied Meteorology, 36(8), 1038-1045. doi:10.1175/1520-0450(1997)0362.0.co;2Tyndall, J., & Colletti, J. (2006). Mitigating swine odor with strategically designed shelterbelt systems: a review. Agroforestry Systems, 69(1), 45-65. doi:10.1007/s10457-006-9017-6Tyndall, J. C., & Grala, R. K. (2008). Financial feasibility of using shelterbelts for swine odor mitigation. Agroforestry Systems, 76(1), 237-250. doi:10.1007/s10457-008-9140-7Ubeda-Sanchez Y, Calvet S, Lopez-Jimenez PA, Torres AG, 2010. Guía técnica para la gestión de las emisiones odoríferas generadas por las explotaciones ganaderas intensivas. Conselleria de Medi Ambient, Aigua, Urbanisme i Habitatge, Valencia (Spain), 101 pp.Ullman JL, Mukhtar S, Lacey RE, Carey JB, 2004. A review of literature concerning odors, ammonia and dust from broiler production facilities: 4. Remedial management practices. J Appl Poult Res 13(3): 521-531.Van Buggenhout, S., Van Brecht, A., Eren Özcan, S., Vranken, E., Van Malcot, W., & Berckmans, D. (2009). Influence of sampling positions on accuracy of tracer gas measurements in ventilated spaces. Biosystems Engineering, 104(2), 216-223. doi:10.1016/j.biosystemseng.2009.04.018Van Harreveld AP, 2001. From odorant formation to odour nuisance: new definitions for discussing a complex process. Water Sci Technol 44(9): 9-15.A. C. VanderZaag, R. J. Gordon, V. M. Glass, & R. C. Jamieson. (2008). Floating Covers to Reduce Gas Emissions from Liquid Manure Storages: A Review. Applied Engineering in Agriculture, 24(5), 657-671. doi:10.13031/2013.25273Varel VH, 2002. Livestock manure odor abatement with plant-derived oils and nitrogen conservation with urease inhibitors: a review. J Anim Sci 80: E1-E7.Verdoes N, Ogink NWM, 1997. Odour emission from pig houses with low ammonia emission. Proc Int Symposium on Ammonia and Odour Control from Animal Production Facilities (Voermans JAM & Monteny GJ, eds). Rosmalen, The Netherlands. pp: 317–325.Wang, K., Wei, B., Zhu, S., & Ye, Z. (2011). Ammonia and odour emitted from deep litter and fully slatted floor systems for growing-finishing pigs. Biosystems Engineering, 109(3), 203-210. doi:10.1016/j.biosystemseng.2011.04.001P. W. Westerman, & R. H. Zhang. (1997). AERATION OF LIVESTOCK MANURE SLURRY AND LAGOON LIQUID FOR ODOR CONTROL: A REVIEW. Applied Engineering in Agriculture, 13(2), 245-249. doi:10.13031/2013.21596Z. Yu, H. Guo, & C. Laguë. (2010). Livestock Odor Dispersion Modeling: A Review. Transactions of the ASABE, 53(4), 1231-1244. doi:10.13031/2013.32588R. H. Zhang, & P. W. Westerman. (1997). SOLID-LIQUID SEPARATION OF ANNUAL MANURE FOR ODOR CONTROL AND NUTRIENT MANAGEMENT. Applied Engineering in Agriculture, 13(3), 385-393. doi:10.13031/2013.21614Zhang, S., Cai, L., Koziel, J. A., Hoff, S. J., Schmidt, D. R., Clanton, C. J., … Heber, A. J. (2010). Field air sampling and simultaneous chemical and sensory analysis of livestock odorants with sorbent tubes and GC–MS/olfactometry. Sensors and Actuators B: Chemical, 146(2), 427-432. doi:10.1016/j.snb.2009.11.028Zhang, Z., Zhu, J., & Park, K. J. (2004). Effects of Duration and Intensity of Aeration on Solids Decomposition in Pig Slurry for Odour Control. Biosystems Engineering, 89(4), 445-456. doi:10.1016/j.biosystemseng.2004.08.00

Methicillin Resistant Staphylococcus aureus ST398 in Veal Calf Farming: Human MRSA Carriage Related with Animal Antimicrobial Usage and Farm Hygiene

Introduction Recently a specific MRSA sequence type, ST398, emerged in food production animals and farmers. Risk factors for carrying MRSA ST398 in both animals and humans have not been fully evaluated. In this cross-sectional study, we investigated factors associated with MRSA colonization in veal calves and humans working and living on these farms. Methods A sample of 102 veal calf farms were randomly selected and visited from March 2007–February 2008. Participating farmers were asked to fill in a questionnaire (n = 390) to identify potential risk factors. A nasal swab was taken from each participant. Furthermore, nasal swabs were taken from calves (n = 2151). Swabs were analysed for MRSA by selective enrichment and suspected colonies were confirmed as MRSA by using slide coagulase test and PCR for presence of the mecA-gene. Spa types were identified and a random selection of each spa type was tested with ST398 specific PCR. The Sequence Type of non ST398 strains was determined. Data were analyzed using logistic regression analysis. Results Human MRSA carriage was strongly associated with intensity of animal contact and with the number of MRSA positive animals on the farm. Calves were more often carrier when treated with antibiotics, while farm hygiene was associated with a lower prevalence of MRSA. Conclusion This is the first study showing direct associations between animal and human carriage of ST398. The direct associations between animal and human MRSA carriage and the association between MRSA and antimicrobial use in calves implicate prudent use of antibiotics in farm animals

Allocation, not male resistance, increases male frequency during epidemics: a case study in facultatively sexual hosts

Why do natural populations vary in the frequency of sexual reproduction? Virulent parasites may help explain why sex is favored during disease epidemics. To illustrate, we show a higher frequency of males and sexually produced offspring in natural populations of a facultative parthenogenetic host during fungal epidemics. In a multi‐year survey of 32 lakes, the frequency of males (an index of sex) was higher in populations of zooplankton hosts with larger epidemics. A lake mesocosm experiment established causality: experimental epidemics produced a higher frequency of males relative to disease‐free controls. One common explanation for such a pattern involves Red Queen (RQ) dynamics. However, this particular system lacks key genetic specificity mechanisms required for the RQ, so we evaluated two other hypotheses. First, individual females, when stressed by infection, could increase production of male offspring vs. female offspring (a tenant of the “Abandon Ship” theory). Data from a life table experiment supports this mechanism. Second, higher male frequency during epidemics could reflect a purely demographic process (illustrated with a demographic model): males could resist infection more than females (via size‐based differences in resistance and mortality). However, we found no support for this resistance mechanism. A size‐based model of resistance, parameterized with data, revealed why: higher male susceptibility negated the lower exposure (a size‐based advantage) of males. These results suggest that parasite‐mediated increases in allocation to sex by individual females, rather than male resistance, increased the frequency of sex during larger disease epidemics.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/139080/1/ecy1976-sup-0001-AppendixS1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139080/2/ecy1976.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139080/3/ecy1976-sup-0002-AppendixS2.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139080/4/ecy1976_am.pd

Ankyrin–Tiam1 Interaction Promotes Rac1 Signaling and Metastatic Breast Tumor Cell Invasion and Migration

Tiam1 (T-lymphoma invasion and metastasis 1) is one of the known guanine nucleotide (GDP/GTP) exchange factors (GEFs) for Rho GTPases (e.g., Rac1) and is expressed in breast tumor cells (e.g., SP-1 cell line). Immunoprecipitation and immunoblot analyses indicate that Tiam1 and the cytoskeletal protein, ankyrin, are physically associated as a complex in vivo. In particular, the ankyrin repeat domain (ARD) of ankyrin is responsible for Tiam1 binding. Biochemical studies and deletion mutation analyses indicate that the 11–amino acid sequence between amino acids 717 and 727 of Tiam1 (717GEGTDAVKRS727L) is the ankyrin-binding domain. Most importantly, ankyrin binding to Tiam1 activates GDP/GTP exchange on Rho GTPases (e.g., Rac1)

Revival of the magnetar PSR J1622-4950: observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

New radio (MeerKAT and Parkes) and X-ray (XMM-Newton, Swift, Chandra, and NuSTAR) observations of PSR J1622-4950 indicate that the magnetar, in a quiescent state since at least early 2015, reactivated between 2017 March 19 and April 5. The radio flux density, while variable, is approximately 100x larger than during its dormant state. The X-ray flux one month after reactivation was at least 800x larger than during quiescence, and has been decaying exponentially on a 111+/-19 day timescale. This high-flux state, together with a radio-derived rotational ephemeris, enabled for the first time the detection of X-ray pulsations for this magnetar. At 5%, the 0.3-6 keV pulsed fraction is comparable to the smallest observed for magnetars. The overall pulsar geometry inferred from polarized radio emission appears to be broadly consistent with that determined 6-8 years earlier. However, rotating vector model fits suggest that we are now seeing radio emission from a different location in the magnetosphere than previously. This indicates a novel way in which radio emission from magnetars can differ from that of ordinary pulsars. The torque on the neutron star is varying rapidly and unsteadily, as is common for magnetars following outburst, having changed by a factor of 7 within six months of reactivation.Comment: Published in ApJ (2018 April 5); 13 pages, 4 figure

An empirical model for probabilistic decadal prediction: global attribution and regional hindcasts

Empirical models, designed to predict surface variables over seasons to decades ahead, provide useful benchmarks for comparison against the performance of dynamical forecast systems; they may also be employable as predictive tools for use by climate services in their own right. A new global empirical decadal prediction system is presented, based on a multiple linear regression approach designed to produce probabilistic output for comparison against dynamical models. A global attribution is performed initially to identify the important forcing and predictor components of the model . Ensemble hindcasts of surface air temperature anomaly fields are then generated, based on the forcings and predictors identified as important, under a series of different prediction ‘modes’ and their performance is evaluated. The modes include a real-time setting, a scenario in which future volcanic forcings are prescribed during the hindcasts, and an approach which exploits knowledge of the forced trend. A two-tier prediction system, which uses knowledge of future sea surface temperatures in the Pacific and Atlantic Oceans, is also tested, but within a perfect knowledge framework. Each mode is designed to identify sources of predictability and uncertainty, as well as investigate different approaches to the design of decadal prediction systems for operational use. It is found that the empirical model shows skill above that of persistence hindcasts for annual means at lead times of up to 10 years ahead in all of the prediction modes investigated. It is suggested that hindcasts which exploit full knowledge of the forced trend due to increasing greenhouse gases throughout the hindcast period can provide more robust estimates of model bias for the calibration of the empirical model in an operational setting. The two-tier system shows potential for improved real-time prediction, given the assumption that skilful predictions of large-scale modes of variability are available. The empirical model framework has been designed with enough flexibility to facilitate further developments, including the prediction of other surface variables and the ability to incorporate additional predictors within the model that are shown to contribute significantly to variability at the local scale. It is also semi-operational in the sense that forecasts have been produced for the coming decade and can be updated when additional data becomes available