Hubble Space Telescope weak lensing study of the z=0.83 cluster MS 1054-03

We have measured the weak gravitational lensing signal of MS 1054-03, a rich and X-ray luminous cluster of galaxies at a redshift of z=0.83, using a two-colour mosaic of deep WFPC2 images. The small corrections for the size of the PSF and the high number density of background galaxies obtained in these observations result in an accurate and well calibrated measurement of the lensing induced distortion. The strength of the lensing signal depends on the redshift distribution of the background galaxies. We used photometric redshift distributions from the Northern and Southern Hubble Deep Fields to relate the lensing signal to the mass. The predicted variations of the signal as a function of apparent source magnitude and colour agrees well with the observed lensing signal. We determine a mass of (1.2+-0.2)x10^15 Msun within an aperture of radius 1 Mpc. Under the assumption of an isothermal mass distribution, the corresponding velocity dispersion is 1311^{+83}_{-89} km/s. For the mass-to-light ratio we find 269+-37 Msun/Lsun. The errors in the mass and mass-to-light ratio include the contribution from the random intrinsic ellipticities of the source galaxies, but not the (systematic) error due to the uncertainty in the redshift distribution. However, the estimates for the mass and mass-to-light ratio of MS 1054-03 agree well with other estimators, suggesting that the mass calibration works well. The reconstruction of the projected mass surface density shows a complex mass distribution, consistent with the light distribution. The results indicate that MS 1054-03 is a young system. The timescale for relaxation is estimated to be at least 1 Gyr. Averaging the tangential shear around the cluster galaxies, we find that the velocity dispersion of an Lstar galaxy is 203+-33 km/s.Comment: 21 pages, Latex, with 27 figures (3 figures bitmapped), ApJ, in press. Version (with non-bitmapped figures) available at http://www.astro.rug.nl/~hoekstra/papers.htm

Teachers Attitude to Curriculum Change: Implications for Inclusive Education in Nigeria

The study investigated teachers’ attitude towards implementing inclusive education in secondary schools in Owerri Education Zone of Imo State, Nigeria. The study adopted a survey research design and was guided by three research questions. The instrument for data collection was a researcher designed questionnaire of three parts. Part A dealt with teachers attitude towards inclusion (TAIS), part B dealt with teachers’ views on inclusive education (TVIS) while the third part dealt with teachers barriers to inclusion (TBIS). The sample comprised 255 secondary school teachers from the zone. Data collected were analyzed using mean and standard deviation. Findings indicated that secondary school teachers in Owerri Education zone have positive attitude and views towards inclusive education. However, lack of training and instructional materials as well as disenabling environment were major barriers to the adoption of inclusive practices. It was recommended that teachers should be exposed to in-service training, workshops and conferences to equip them for the challenges of inclusion. Special education should also be a core subject in all teacher training colleges, Colleges of Education and Faculties of Education in Nigeria. Government should endeavour to restructure school environment to suit inclusive standards and also provide assistive technology in order to meet the UNESCO global objectives of inclusion. Keywords: Attitude, Change, Implementation, Inclusive Education, teache

Recent epidemiologic trends in periodontitis in the USA

The most important development in the epidemiology of periodontitis in the USA during the last decade is the result of improvements in survey methodologies and statistical modeling of periodontitis in adults. Most of these advancements have occurred as the direct outcome of work by the joint initiative known as the Periodontal Disease Surveillance Project by the Centers for Disease Control and Prevention and the American Academy of Periodontology that was established in 2006. This report summarizes some of the key findings of this important initiative and its impact on our knowledge of the epidemiology of periodontitis in US adults. This initiative first suggested new periodontitis case definitions for surveillance in 2007 and revised them slightly in 2012. This classification is now regarded as the global standard for periodontitis surveillance and is used worldwide. First, application of such a standard in reporting finally enables results from different researchers in different countries to be meaningfully compared. Second, this initiative tackled the concern that prior national surveys, which used partial‐mouth periodontal examination protocols, grossly underestimated the prevalence of periodontitis of potentially more than 50%. Consequently, because previous national surveys significantly underestimated the true prevalence of periodontitis, it is not possible to extrapolate any trend in periodontitis prevalence in the USA over time. Any difference calculated may not represent any actual change in periodontitis prevalence, but rather is a consequence of using different periodontal examination protocols. Finally, the initiative addressed the gap in the need for state and local data on periodontitis prevalence. Through the direct efforts of the Centers for Disease Control and Prevention and the American Academy of Periodontology initiative, full‐mouth periodontal probing at six sites around all nonthird molar teeth was included in the 6 years of National Health and Nutrition Examination Surveys from 2009‐2014, yielding complete data for 10 683 dentate community‐dwelling US adults aged 30 to 79 years. Applying the 2012 periodontitis case definitions to the 2009‐2014 National Health and Nutrition Examination Surveys data, the periodontitis prevalence turned out to be much greater than previously estimated, namely affecting 42.2% of the population with 7.8% of people experiencing severe periodontitis. It was also discovered that only the moderate type of periodontitis is driving the increase in periodontitis prevalence with age, not the mild or the severe types whose prevalence do not increase consistently with age, but remain ~ 10%‐15% in all age groups of 40 years and older. The greatest risk for having periodontitis of any type was seen in older people, in males, in minority race/ethnic groups, in poorer and less educated groups, and especially in cigarette smokers. The Centers for Disease Control and Prevention and the American Academy of Periodontology initiative reported, for the first time, the periodontitis prevalence estimated at both local and state levels, in addition to the national level. Also, this initiative developed and validated in field studies a set of eight items for self‐reported periodontitis for use in direct survey estimates of periodontitis prevalence in existing state‐based surveys. These items were also included in the 2009‐2014 National Health and Nutrition Examination Surveys for validation against clinically determined cases of periodontitis. Another novel result of this initiative is that, for the first time, the geographic distribution of practicing periodontists in relation to the geographic distribution of people with severe periodontitis is illustrated. In summary, the precise periodontitis prevalence and distribution among subgroups in the dentate US noninstitutionalized population aged 30‐79 years is better understood because of application of valid periodontitis case definitions to full‐mouth periodontal examination, in combination with reliable information on demographic and health‐related measures. We now can monitor the trend of periodontitis prevalence over time as well as guide public health preventive and intervention initiatives for the betterment of the health of the adult US population.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153044/1/prd12323.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/153044/2/prd12323_am.pd

Breaking Seed Dormancy: Effect of Heat and Vimpel® on Oil Palm Seed Germination (EIaeis guineensis Jacq)

Oil palm (E. guineensis) is native to Africa and among highest oilseeds crop in the world, having a dormant seeds which require pre-treatments to quicken the germination process. The objective of this experiment is to evaluate the effects of Vimpel growth regulator on germination of Oil palm seedlings. The viable seeds of oil palm were treated with vimpel solution at different stages of the germination process tagged as A (+ Vimpel before heat), B (+Vimpel after heat), C (+Vimpel without heat) D (0 vimpel) E (+ Vimpel prior and after heat) and F (Water prior and after heating/Control) and then subjected to six different temperature regime i.e. 2,4,6,8, 10 and 12 weeks in the germination chamber. The result indicates that group A had the highest germination percentage at 10 weeks of heat treatment followed by B at 8 weeks of temperature while group F (control) had the lowest percentage. Conclusively, the vimpel growth regulator has significant effects in facilitating the germination process by 40 days against 80 days of heat treatment currently use in the oil palm seed germination

Use of Java RMI on Mobile Devices for Peer to Peer Computing

In this paper, the use of Java RMI on mobile devices for peer-to-peer computing is presented. An overview of the commonly used distributed middleware systems are described by looking into remote procedure call (RPC) and object oriented middleware java remote method invocation (Java RMI). The differences between this middleware are equally detailed in this work. A review of some related literature was carried out and some of the features required for the proposed prototype were also extracted accordingly. This paper also provides an overview of peer-to-peer networking and some of the application areas linked to the platform implementation. Detailed design and implementation of the artifact for peer-to-peer network using Java 2 platform programming language were carried out. Finally, on the process of this research, three applications were developed and peered together to show that java RMI is a tool for peer-to-peer computing. Keywords: - Remote method invocation, Remote procedure call, Stub, Skeleton, Peer-to-Pee

Weak Lensing by High-Redshift Clusters of Galaxies - I: Cluster Mass Reconstruction

We present the results of a weak lensing survey of six high-redshift (z > 0.5), X-ray selected clusters of galaxies. We have obtained ultra-deep R-band images of each cluster with the Keck Telescope, and have measured a weak lensing signal from each cluster. From the background galaxy ellipticities we create two-dimensional maps of the surface mass density of each cluster. We find that the substructure seen in the mass reconstructions typically agree well with substructure in both the cluster galaxy distributions and X-ray images of the clusters. We also measure the one-dimensional radial profiles of the lensing signals and fit these with both isothermal spheres and "universal" CDM profiles. We find that the more massive clusters are less compact and not as well fit by isothermal spheres as the less massive clusters, possibly indicating that they are still in the process of collapse.Comment: 43 pages, 15 figures, uses aastex, submitted to ApJ 4 color plates produced here as jpg's, larger versions of the jpgs can be found at http://www.mpa-garching.mpg.de/~clow

Dental visits among adult Hispanics – BRFSS 1999 and 2006

Objectives: This study examined and compared utilization of dental services by adult US Hispanics 18 years and older in the years 1999 and 2006. Methods: Dental utilization data collected by telephone interviews by the state‐based Behavioral Risk Factor Surveillance System (BRFSS) were analyzed. Results: In 2006, the state mean and median prevalence of adult Hispanics with dental visits during the past year were 56.2 percent and 62.1 percent, respectively, and had not changed significantly since 1999. In 40 states, utilization was well below the national prevalence of 70.3 percent. Frequency of dental visits was significantly higher among females and those with higher income (>$50,000), higher education, nonsmokers, and persons having medical health insurance. Conclusions: Findings from this study suggest that barriers to utilization of dental services among Hispanic adults exist in most states and may contribute to existing oral health disparities. The magnitude of this problem may increase in the future with the expansion of the US Hispanic population.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87091/1/j.1752-7325.2011.00259.x.pd