301 research outputs found
Designing And Validating The Methodology For The Internet Assessment Of Fish Consumption At A University Setting
Assessing fish consumption is complex and involves several factors; however, the use of questionnaires in surveys and the use of the Internet as tool to collect data have been considered promising approaches. Therefore, the objective of this research was to design a data collection technique using a questionnaire to assess fish consumption by making it available on a specific home page on the Internet. A bibliographical survey or review was carried out to identify the features of the instrument, and therefore pre-tests were conducted with previous instruments, followed by the Focus Group technique. Specialists then performed an analysis and conducted an online pre-test. Multivariate data analysis was applied using the SmartPLS software. The results indicate that 1.966 participants belonging to the University of São Paulo (USP) community participated in the test, and after the exclusion of some variables, a statistically significant results were obtained. The final constructs comprised consumption, quality, and general characteristics. The instrument consisted of behavioral statements in a 5-point Likert scale and multiple-choice questions. The Cronbach's alpha reliability coefficient was 0.66 for general characteristics, 0.98 for quality, and 0.91 for consumption, which indicate good reliability of the instrument. In conclusion, the results proved that the Internet assessment is efficient. The instrument of analysis allowed us to better understand the process of buying and consuming fish in the country, and it can be used as base for further research.342315323Bargas-Avila, J.A., Lotscher, J., Orsini, S., Opwis, K., Intranet satisfaction questionnaire: Development and validation of a questionnaire to measure user satisfaction with the Intranet (2009) Computers In Human Behavior, 25 (6), pp. 1241-1250. , http://dx.doi.org/10.1016/j.chb.2009.05.014Batagelj, Z., Vehovar, V., Technical and methodological issues in surveys (1998) Proceedings of the 53° Annual Conference of the American Association For Public Opinion Research (AAPOR), , http://www.ris.org/ris98/stlouis, St. Louis. Retrieved fromBliven, B., Kaufman, S., Spertus, J.A., Electronic collection of health-related quality of life data: Validity, time, benefits and patient preference (2001) Quality Life Research, 10 (1), pp. 15-22. , http://dx.doi.org/10.1023/A:1016740312904Boeckner, L., Pullen, S.C.H., Walker, S.N., Abbott, G.W., Block, T., Use and realiability of Word Wide Web Version of the block health habits and history questionnaire with older rural women (2002) Journal of Nutrition Education and Behavior, 34, pp. S20-S24. , http://dx.doi.org/10.1016/S1499-4046(06)60307-2Cantrell, M.A., Lupinacci, P., Methodological issues in online data collection (2007) Journal of Advanced Nursing, 60 (5), pp. 544-549. , http://dx.doi.org/10.1111/j.1365-2648.2007.04448.xChang, L., Krosnick, J.A., Comparing oral interviewing with self-administered computerized questionnaires an experiment (2010) Public Opinion Quarterly, 74 (1), pp. 154-167. , http://dx.doi.org/10.1093/poq/nfp090Chin, W.W., The partial least squares approach to structural equation modeling (1998) Modern Methods For Business Research, pp. 295-336. , In G. A. Marcoulides (Ed.), Mahwah: Lawrence Erlbaum AssociatesCronk, B.C., West, J.L., Personality research on the Internet: A comparison of web based and traditional instruments in take-home and in-class settings (2002) Behavior Research Methods Instruments and Computers, 34 (2), pp. 177-180. , http://dx.doi.org/10.3758/BF03195440Falk, R.F., Miller, N.B., (1992) A Primer For Soft Modeling, , New York: Akron Presshttp://www.brasilfoodtrends.com.br/Brasil_Food_Trends/index.html, Federação das Industrias do Estado de São Paulo-FIESP. (2010), Brasil food trends, São Paulo: FIESP. Retrieved fromFerri, P., Cavalli, N., Costa, E., Mangiatordi, A., Mizzella, S., Pozzali, A., Scenini, F., Italian university students and digital technologies: Some results from a field research (2009) Communications In Computer and Information Science, 49 (3), pp. 357-365. , http://dx.doi.org/10.1007/978-3-642-04757-2_38(2009) The State of World Fisheries and Aquaculture (SOFIA), , Food and Agriculture Organization of the United Nations-FAO, Rome: FAOGefen, D., Straub, D.W., Boudreau, M.C., Structural equation modeling and regression: Guidelines for research practice (2009) Communications of the Association For Information Systems, 4 (1), pp. 1-77Hair Jr., J.F., Black, W.C., Babin, B.J., Anderson, R.E., Tatham, R.L., (2009) Análise Multivariada De Dados, , 6. ed.). Porto Alegre: BookmanHanning, R.M.D., Royall, J.E., Toews, L., Blashill, L., Wegener, J., Driezen, P., Web-based food behaviour questionnaire: Validation with grades six to eight students (2009) Canadian Journal of Dietetic Practice and Research, 70, pp. 172-178. , http://dx.doi.org/10.3148/70.4.2009.172Hanscom, B., Lurie, J.D., Homa, K., Weinstein, J., Computerized questionnaires and the quality of survey data (2002) Spine, 27 (6), pp. 1797-1801. , http://dx.doi.org/10.1097/00007632-200208150-00020Hershberger, S.L., Marcoulides, G.A., Parramore, M.M., Structural equation modeling: An introduction (2003) Structural Equation Modeling: Applications In Ecological and Evolutionary Biology, , http://dx.doi.org/10.1017/CBO9780511542138.002, In B. H. Pugesek, A. Tomer & A. V. Eye (Eds.), Cambridge: Cambridge University PressKlem, L., Structural equation modeling (2006) Reading and Understanding More Multivariate Statistics, pp. 227-260. , In L. G. Grimm & P. R. Yarnold (Eds.), Washington: American Psychological AssociationMalhotra, N., (2008) Pesquisa De Marketing: Uma Orientação Aplicada, , 5. ed.). Porto Alegre: BookmanMaruayama, G.M., (1998) Basic of Structural Equation Modeling, , Thousand Oaks: Sage PublicationsMatthys, C., Pynaert, I., de Keyzer, W., Henauw, S., Validity and reproducibility of an adolescent Web-based food frequency questionnaire (2007) Journal of the American Dietetic Association, 107 (4), pp. 605-610. , http://dx.doi.org/10.1016/j.jada.2007.01.005Mina, K., Fritschi, L., Knuiman, M., A valid semiquantitative food frequency questionnaire to measure fish consumption (2007) European Journal of Clinical Nutrition, 61, pp. 1023-1031. , http://dx.doi.org/10.1038/sj.ejcn.1602617Morgan, D., (1997) Focus Group As Qualitative Research, pp. 80-88. , London: Sage Publications. Qualitative Research Methods Series 16Mueller, R.O., Structural equation modeling: Back to basics (1997) Structural Equation Modeling, 4 (4), pp. 353-369. , http://dx.doi.org/10.1080/10705519709540081Oetterer, M., (2002) Industrialização Do Pescado Cultivado, , Guaíba: AgropecuáriaPasquali, L., (2003) Psicometria: Teoria Dos Testes Na Psicologia E Na Educação, , Petrópolis: VozesPerez, G., Zwicker, R., Fatores determinantes da adoção de sistemas de informação na área de saúde: Um estudo sobre o prontuário médico eletrônico (2010) Revista De Administração Mackenzie, 11 (1), pp. 174-200. , http://dx.doi.org/10.1590/S1678-69712010000100008Ribeiro, R.C.L., Panato, E., Silva, M.M.S., Rosado, L.E.F., Rosado, G.P., Validade relativa de um questionário de freqüência alimentar para utilização em adultos (2009) Revista De Nutrição, 22 (1), pp. 81-95. , http://dx.doi.org/10.1590/S1415-52732009000100008Rodrigues, D.S., Ramos, R.A.R., Mendes, J.F.G., A system to evaluate and monitor quality of life in a University Campus (2005) Proceedings of the 9th International Conference On Computers In Urban Planning and Urban Management (CUPUM), , http://repositorium.sdum.uminho.pt/bitstream/1822/5064/1/Rodrigues_CI_1_2005.pdf, London. Retrieved fromSantos, F.V., (2001) A Importância Da Atividade Física Na Qualidade De Vida Disseminada Numa Página Da Internet (Dissertação De Mestrado), , Universidade Federal de Santa Catarina, FlorianópolisSirot, V., Dumas, C., Leblanc, J.C., Margarit, I., Food and nutrient intakes of French frequent seafood consumers with regard to fish consumption recommendations: Results from the CALIPSO study (2011) British Journal of Nutrition, 105 (9), pp. 1369-1380. , http://dx.doi.org/10.1017/S0007114510005027Sonoda, D.Y., (2006) Demanda Por Pescado No Brasil Entre 2002 E 2003, , Tese de doutorado). Universidade de São Paulo, PiracicabaSoriano, J.M., Molto, J.C., Manes, J., Dietary intake and food pattern among university students (2000) Nutrition Research, 20 (9), pp. 1249-1258. , http://dx.doi.org/10.1016/S0271-5317(00)00217-7Stanton, J.M., Rogelberg, S.G., Using Internet/intranet web pages to collect organizational research data (2001) Organizational Research Methods, 4 (3), pp. 200-217. , http://dx.doi.org/10.1177/109442810143002Touvier, M., Kesse-Guyot, E., Méjean, C., Pollet, C., Malon, A., Castetbon, K., Hercberg, S., Comparison between an interactive web-based self-administered 24 h dietary record and an interview by a dietitian for large-scale epidemiological studies (2001) British Journal of Nutrition, 105 (7), pp. 1055-1064. , http://dx.doi.org/10.1017/S0007114510004617Trondsen, T., Scholderer, J., Lund, E., Lund, E., Eggen, A., Perceived barriers to consumption of fish among Norwegian women (2003) Appetite, 41 (3), pp. 301-314. , http://dx.doi.org/10.1016/S0195-6663(03)00108-9(2010) Anuário Estatístico, , http://sistemas3.usp.br/anuario, Universidade de São Paulo-USP, Brasil: USP. Retrieved fromVanderslice, J., Laflamme, D.M., Wynkoop-Simmons, K., Comparing fish consumption information collected via a telephone survey and a food frequency questionnaire (2008) Epidemiology, 19 (6), pp. S315Veiga, L., Gondim, S.M.G., A utilização de métodos qualitativos na ciência política e no marketing político (2001) Opinião Pública, 2 (1), pp. 1-15Vinholis, M.M.B., Azevedo, P.F., Segurança do alimento e rastreabilidade: O caso BSE (2002) RAE Eletrônica, 1 (2), pp. 1-19. , http://dx.doi.org/10.1590/S1676-56482002000200008Zwicker, R., Souza, C.A., Bido, D.S., (2008) Uma Revisão Do Modelo Do Grau De Informatização De Empresas: Novas Propostas De Estimação E Modelagem Usando PLS (Partial Least Squares), , In Anais do 32° Encontro da ANPAD, Rio de Janeiro. CD-RO
Application Of Exploratory Factor Analysis To Assess Fish Consumption In A University Community [aplicação De Análise Fatorial Exploratória Para Avaliar O Consumo De Pescado Em Uma Comunidade Universitária]
The objective of this research was to use the technique of Exploratory Factor Analysis (EFA) for the adequacy of a tool for the assessment of fish consumption and the characteristics involved in this process. Data were collected during a campaign to encourage fish consumption in Brazil with the voluntarily participation of members of a university community. An assessment instrument consisting of multiple-choice questions and a five-point Likert scale was designed and used to measure the importance of certain attributes that influence the choice and consumption of fish. This study sample was composed of of 224 individuals, the majority were women (65.6%). With regard to the frequency of fish consumption, 37.67% of the volunteers interviewed said they consume the product two or three times a month, and 29.6% once a week. The Exploratory Factor Analysis (EFA) was used to group the variables; the extraction was made using the principal components and the rotation using the Quartimax method. The results show clusters in two main constructs, quality and consumption with Cronbach Alpha coefficients of 0.75 and 0.69, respectively, indicating good internal consistency.33199106Alves, A.L.S., Padrão alimentar de mulheres adultas (2006) Revista De Saúde Pública, 40 (5), pp. 865-873. , PMid:17301909Anastasi, A., Urbina, S., (2000) Testagem Psicológica, p. 575. , 7. ed. Porto Alegre: ArtMedBlank, L., Community based lifestyle interventions: Changing behaviour and improving health (2007) Public Health Nutrition, 29 (3), pp. 236-245. , http://dx.doi.org/10.1093/pubmed/fdm041, PMid:17601764(2010), http://www.mpa.gov.br/mpa/seap/html/Comercializacao/semana_do_peixe_int2 009.html, BRASIL. Ministério da Pesca e Aquicultura. A campanha vai ressaltar os benefícios do consumo de pescado e o seu prepare MPA, 2010a. Disponível em: Acesso em: 25 out(2010) Consumo Per Capita Aparente De Pescado No Brasil 1996-2009 - O Brasileiro Está Comendo Mais Pescado, , http://www.mpa.gov.br/mpa/seap/Jonathan/mpa3/docs/folder%20consumo%20de% 20pescado%202009%202.pdf, BRASIL. Ministério da Pesca e Aquicultura, MPA, 2010b. Disponível em, Acesso em: 02 outBurger, J., Fishing, fish consumption, and awareness about warnings in a university community in central New Jersey in 2007, and comparisons with 2004 (2008) Environmental Research, 108 (1), pp. 107-116. , http://dx.doi.org/10.1016/j.envres.2008.05.003, PMid:18632098Cooper, D.R., Schindler, P.S., (2003) Métodos De Pesquisa Em Administração, p. 640. , 7. ed. Porto Alegre: BookmanDijk, H.V., Perceptions of health risks and benefits associated with fish consumption among Russian consumers (2011) Appetite, 56 (2), pp. 227-234. , http://dx.doi.org/10.1016/j.appet.2010.12.008, PMid:21147191Dillon, W.R., Goldstein, M., (1984) Multivariate Analysis: Methods and Applications, p. 608. , USA: John Wiley and sons, Inc(2009) The State of World Fisheries and Aquaculture (SOFIA): 2008, p. 196. , FOOD AND AGRICULTURE ORGANIZATION - FAO, FAOFilho, F.D.B., Silva Jr., J.A., Visão além do alcance: Uma introdução à análise fatorial (2010) Opinião Pública, 16 (1), pp. 160-185. , http://dx.doi.org/10.1590/S0104-62762010000100007Hair Jr., F., (2009) Análise Multivariada De Dados, p. 688. , 6. ed. Porto Alegre: BookmanHarris, C.A., Knight, S., Worosz, M.R., Shopping for food safety and the public trust: What supply chain stakeholders need to know about consumer attitudes (2006) Food Safety Magazine, pp. 52-59. , http://www.foodsafetymagazine.com/articleFF.asp?id=723&sub=sub1, Disponível em, Acesso em: 19 marHonkanen, P., Olsen, S.O., Verplanken, B., Intention to consume seafood - the importance of habit (2005) Appetite, 45 (2), pp. 161-168. , http://dx.doi.org/10.1016/j.appet.2005.04.005, PMid:16011859Johnson, R.A., Wichern, D.W., (2000) Métodos Mutivariados Aplicados De Análise De Dados, , México: International Thomson EditoresMaciel, E.S., Inquérito sobre o consumo de pescado em feira comemorativa da "Semana do Peixe" em cidade do interior de São Paulo (2009) Revista Ciência E Tecnologia - UNIMEP, 31 (16), pp. 59-68Malhotra, N., (2006) Pesquisa De Marketing Uma Orientação Aplicada, p. 720. , Porto Alegre: BookmanMichels, I.L., Prochmann, A.M., (2010) Estudo Das Cadeias Produtivas De Mato Grosso Do Sul: Piscicultura, p. 152. , http://pt.scribd.com/doc/14791838/Cadeia-Produtiva-Da-Piscicultura-Em-MS -2003, UFMS, 2002, Disponível, em, Acesso em: 08 novMunõz, M.A., Adherence to the Mediterranean diet is associated with better mental and physical health (2009) British Journal of Nutrition, 101 (12), pp. 1821-1827. , http://dx.doi.org/10.1017/S0007114508143598, PMid:19079848Oetterer, M., (2002) Industrialização Do Pescado Cultivado, p. 200. , Guaíba: Editora AgropecuáriaOlsen, S.O., Exploring the relationship between convenience and fish consumption: A cross-cultural study (2007) Appetite, 49 (1), pp. 84-91. , http://dx.doi.org/10.1016/j.appet.2006.12.002, PMid:17261344Pasquali, L., Extração dos fatores (2005) Análise Fatorial Para Pesquisadores, pp. 55-86. , PASQUALI, L. (Org.), LabPam, PMid:16760627Pieniak, Z., Verbeke, W., Scholderer, J., Health-related beliefs and consumer knowledge as determinants of fish consumption (2010) Journal of Human Nutrition and Dietetics, 23 (5), pp. 480-488. , http://dx.doi.org/10.1111/j.1365-277X.2010.01045.x, PMid:20831707Raspor, P., Faces of foods on the world of food systems (2006) Acta Alimentaria, 35, pp. 247-249Rortveit, A.W., Olsen, S.O., Combining the role of convenience and consideration set size in explaining fish consumption in Norway (2009) Appetite, 52 (2), pp. 313-317. , http://dx.doi.org/10.1016/j.appet.2008.11.001, PMid:19038300Schawb, A.J., (2010) Eletronic Classroom. [online], , http://www.utexas.edu/ssw/eclassroom/schwab.html, Disponível em: Acesso em: 10 setShaw, D., An exploration of values in ethical consumer decision making (2005) Journal of Consumer Behaviour, 4 (3), p. 185. , http://dx.doi.org/10.1002/cb.3Sonoda, D.Y., Caracterização do mercado de pescado no Brasil (2007) Revista Aquicultura E Pesca, 3 (28), pp. 40-44. , jul./ago(1999) Base 10.0 User's Guide, , STATISTICAL PACKAGE FOR THE SOCIAL SCIENCES - SPSS, Chicago: SPSSTrondsen, T., Perceived barriers to consumption of fish among Norwegian women (2003) Appetite, 48, pp. 301-314. , http://dx.doi.org/10.1016/S0195-6663(03)00108-9Tuu, H.H., The role of norms in explaining attitudes, intention and consumption of a common food (fish) in Vietnam (2008) Appetite, 51 (13), pp. 546-551. , http://dx.doi.org/10.1016/j.appet.2008.04.007, PMid:18486275Tyrovolas, S., Panagiotakos, D., The role of Mediterranean type of diet on the development of cancer and cardiovascular disease, in the elderly: A systematic review (2010) Maturitas, 65, pp. 122-130. , http://dx.doi.org/10.1016/j.maturitas.2009.07.003, PMid:19656644Uilde, A.G., Farah, T.G., Flávia, M.M., Caracterização do consumo de carnes no Brasil (2002) Revista Nacional Da Carne, N, p. 310Verbeke, W., Vackier, I., Individual determinants of fish consumption: Application of the theory of planned behavior (2005) Appetite, 44 (1), pp. 67-82. , http://dx.doi.org/10.1016/j.appet.2004.08.006, PMid:15604034Wei, X., Zeng, Y., (2005) Consumer's Attitudes and Willingness-to-pay For Green Food In Beijing, pp. 1-10. , http://sard.ruc.edu.cn/zengyinchu/files/taolunwengao/, Disponível em: Acesso em: 05 fev. 2011Zhou, J.H., Consumer's attitude, perception and purchase behavior - Case from Jiangsu province (2004) Journal of China Agricultural Economics, 11, pp. 44-5
Simultaneous analysis of free amino acids and biogenic amines in honey and wine samples using in loop orthophthalaldeyde derivatization procedure
This work presents a RP-HPLC method for the simultaneous quantification of free amino acids and biogenic amines in liquid food matrices and the results of the application to honey and wine samples obtained from different production processes and geographic origins. The developed methodology is based on a pre-column derivatization with o-phthaldialdehyde carried out in the sample injection loop. The compounds were separated in a Nova-Pack RP-C18 column (150 mm × 3.9 mm, 4 μm) at 35 °C. The mobile phase used was a mixture of phase A: 10 mM sodium phosphate buffer (pH 7.3), methanol and tetrahydrofuran (91:8:1); and phase B: methanol and phosphate buffer (80:20), with a flow rate of 1.0 ml/min. Fluorescence detection was used at an excitation wavelength of 335 nm and an emission wavelength of 440 nm. The separation and quantification of 19 amino acids and 6 amines was carried out in a single run as their OPA/MCE derivatives elute within 80 min, ensuring a reproducible quantification. The method showed to be adequate for the purpose, with an average RSD of 2% for the different amino acids; detection limits varying between 0.71 mg/l (Asn) and 8.26 mg/l (Lys) and recovery rates between 63.0% (Cad) and 98.0% (Asp). The amino acids present at the highest concentration in honey and wine samples were phenylalanine and arginine, respectively. Only residual levels of biogenic amines were detected in the analysed samples
Energy crisis in Brazil: Impact of hydropower reservoir level on the river flow
Water management strategies can have considerable impacts on the regional climate and hydrology. It is usually the case that the construction and operation of hydropower reduce the river flow downstream due to the increase in evaporation. However, this paper shows that in humid regions, such as in Brazil, the hydropower storage reservoirs contribute to increase the flow of the river. This observation has been tested with historical reservoir levels and river flow data from several dams in Brazil. It was found that the operation of reservoirs in Brazil has a considerable impact on its river flows. The higher the storage level at the beginning of the humid period, the higher the river flow during the wet period. The paper proposes strategies to allow the reservoirs to fill up and to maintain the reservoirs filled in the future, with the intention of increasing hydropower generation and reducing the intermittency of other renewable energy sources
Single Spin Asymmetry in Polarized Proton-Proton Elastic Scattering at GeV
We report a high precision measurement of the transverse single spin
asymmetry at the center of mass energy GeV in elastic
proton-proton scattering by the STAR experiment at RHIC. The was measured
in the four-momentum transfer squared range \GeVcSq, the region of a significant interference between the
electromagnetic and hadronic scattering amplitudes. The measured values of
and its -dependence are consistent with a vanishing hadronic spin-flip
amplitude, thus providing strong constraints on the ratio of the single
spin-flip to the non-flip amplitudes. Since the hadronic amplitude is dominated
by the Pomeron amplitude at this , we conclude that this measurement
addresses the question about the presence of a hadronic spin flip due to the
Pomeron exchange in polarized proton-proton elastic scattering.Comment: 12 pages, 6 figure
Longitudinal double-spin asymmetry and cross section for inclusive neutral pion production at midrapidity in polarized proton collisions at sqrt(s) = 200 GeV
We report a measurement of the longitudinal double-spin asymmetry A_LL and
the differential cross section for inclusive Pi0 production at midrapidity in
polarized proton collisions at sqrt(s) = 200 GeV. The cross section was
measured over a transverse momentum range of 1 < p_T < 17 GeV/c and found to be
in good agreement with a next-to-leading order perturbative QCD calculation.
The longitudinal double-spin asymmetry was measured in the range of 3.7 < p_T <
11 GeV/c and excludes a maximal positive gluon polarization in the proton. The
mean transverse momentum fraction of Pi0's in their parent jets was found to be
around 0.7 for electromagnetically triggered events.Comment: 6 pages, 3 figures, submitted to Phys. Rev. D (RC
High non-photonic electron production in + collisions at = 200 GeV
We present the measurement of non-photonic electron production at high
transverse momentum ( 2.5 GeV/) in + collisions at
= 200 GeV using data recorded during 2005 and 2008 by the STAR
experiment at the Relativistic Heavy Ion Collider (RHIC). The measured
cross-sections from the two runs are consistent with each other despite a large
difference in photonic background levels due to different detector
configurations. We compare the measured non-photonic electron cross-sections
with previously published RHIC data and pQCD calculations. Using the relative
contributions of B and D mesons to non-photonic electrons, we determine the
integrated cross sections of electrons () at 3 GeV/10 GeV/ from bottom and charm meson decays to be = 4.0({\rm
stat.})({\rm syst.}) nb and =
6.2({\rm stat.})({\rm syst.}) nb, respectively.Comment: 17 pages, 17 figure
Evolution of the differential transverse momentum correlation function with centrality in Au+Au collisions at GeV
We present first measurements of the evolution of the differential transverse
momentum correlation function, {\it C}, with collision centrality in Au+Au
interactions at GeV. {\it C} exhibits a strong dependence
on collision centrality that is qualitatively similar to that of number
correlations previously reported. We use the observed longitudinal broadening
of the near-side peak of {\it C} with increasing centrality to estimate the
ratio of the shear viscosity to entropy density, , of the matter formed
in central Au+Au interactions. We obtain an upper limit estimate of
that suggests that the produced medium has a small viscosity per unit entropy.Comment: 7 pages, 4 figures, STAR paper published in Phys. Lett.
Longitudinal scaling property of the charge balance function in Au + Au collisions at 200 GeV
We present measurements of the charge balance function, from the charged
particles, for diverse pseudorapidity and transverse momentum ranges in Au + Au
collisions at 200 GeV using the STAR detector at RHIC. We observe that the
balance function is boost-invariant within the pseudorapidity coverage [-1.3,
1.3]. The balance function properly scaled by the width of the observed
pseudorapidity window does not depend on the position or size of the
pseudorapidity window. This scaling property also holds for particles in
different transverse momentum ranges. In addition, we find that the width of
the balance function decreases monotonically with increasing transverse
momentum for all centrality classes.Comment: 6 pages, 3 figure
Energy and system size dependence of \phi meson production in Cu+Cu and Au+Au collisions
We study the beam-energy and system-size dependence of \phi meson production
(using the hadronic decay mode \phi -- K+K-) by comparing the new results from
Cu+Cu collisions and previously reported Au+Au collisions at \sqrt{s_NN} = 62.4
and 200 GeV measured in the STAR experiment at RHIC. Data presented are from
mid-rapidity (|y|<0.5) for 0.4 < pT < 5 GeV/c. At a given beam energy, the
transverse momentum distributions for \phi mesons are observed to be similar in
yield and shape for Cu+Cu and Au+Au colliding systems with similar average
numbers of participating nucleons. The \phi meson yields in nucleus-nucleus
collisions, normalised by the average number of participating nucleons, are
found to be enhanced relative to those from p+p collisions with a different
trend compared to strange baryons. The enhancement for \phi mesons is observed
to be higher at \sqrt{s_NN} = 200 GeV compared to 62.4 GeV. These observations
for the produced \phi(s\bar{s}) mesons clearly suggest that, at these collision
energies, the source of enhancement of strange hadrons is related to the
formation of a dense partonic medium in high energy nucleus-nucleus collisions
and cannot be alone due to canonical suppression of their production in smaller
systems.Comment: 20 pages and 5 figure
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