3,367 research outputs found

    Global to local genetic diversity indicators of evolutionary potential in tree species within and outside forests

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    There is a general trend of biodiversity loss at global, regional, national and local levels. To monitor this trend, international policy processes have created a wealth of indicators over the last two decades. However, genetic diversity indicators are regrettably absent from comprehensive bio-monitoring schemes. Here, we provide a review and an assessment of the different attempts made to provide such indicators for tree genetic diversity from the global level down to the level of the management unit. So far, no generally accepted indicators have been provided as international standards, nor tested for their possible use in practice. We suggest that indicators for monitoring genetic diversity and dynamics should be based on ecological and demographic surrogates of adaptive diversity as well as genetic markers capable of identifying genetic erosion and gene flow. A comparison of past and present genecological distributions (patterns of genetic variation of key adaptive traits in the ecological space) of selected species is a realistic way of assessing the trend of intra-specific variation, and thus provides a state indicator of tree genetic diversity also able to reflect possible pressures threatening genetic diversity. Revealing benefits of genetic diversity related to ecosystem services is complex, but current trends in plantation performance offer the possibility of an indicator of benefit. Response indicators are generally much easier to define, because recognition and even quantification of, e.g., research, education, breeding, conservation, and regulation actions and programs are relatively straightforward. Only state indicators can reveal genetic patterns and processes, which are fundamental for maintaining genetic diversity. Indirect indicators of pressure, benefit, or response should therefore not be used independently of state indicators. A coherent set of indicators covering diversity–productivity–knowledge–management based on the genecological approach is proposed for application on appropriate groups of tree species in the wild and in cultivation worldwide. These indicators realistically reflect the state, trends and potentials of the world’s tree genetic resources to support sustainable growth. The state of the genetic diversity will be based on trends in population distributions and diversity patterns for selected species. The productivity of the genetic resource of trees in current use will reflect the possible potential of mobilizing the resource further. Trends in knowledge will underpin the potential capacity for development of the resource and current management of the genetic resource itself will reveal how well we are actually doing and where improvements are required

    Herkunftsvergleiche von Legehennen in Station und Feld unter besonderer BerĂŒcksichtigung ökologischer Haltungsverfahren

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    Der Beitrag beschreibt die Bedingungen von LegeleistungsprĂŒfungen in Deutschland mit Bezug auf Genotyp Umwelt-Interaktionen. Außerdem werden die Besonderheiten der Eierproduktion auf ökologischer Basis herausgestellt. Daraus werden Anregungen fĂŒr ein Konzept einer zukĂŒnftigen FeldprĂŒfung von Legehennen erarbeitet. In Deutschland werden keine offiziellen LegeleistungsprĂŒfungen der LĂ€nder mehr durchgefĂŒhrt. UnabhĂ€ngige Leistungsinformationen aus Herkunftsvergleichen stehen daher nur aus einzelnen PrĂŒfungen (LfL Bayern, 2006) zur VerfĂŒgung. Interaktionen zwischen LegehennenherkĂŒnften und unterschiedlichen Haltungssystemen sind nach Literaturangaben gut belegt. FĂŒr die Ökoproduktion von Eiern ist aufgrund der produktionstechnischen Unterschiede zur konventionellen Produktion ebenfalls mit solchen Wechselwirkungen zu rechnen. Deshalb braucht die ökologische Eierproduktion eine LeistungsprĂŒfung, die auf die speziellen Produktionsbedingungen abgestimmt ist. Die Entwicklung eines Feldtests fĂŒr Legehennen in ökologischer Haltung kann daher ein Weg sein, das gegenwĂ€rtige Informationsdefizit der Landwirte ĂŒber die Leistung und das Verhalten erhĂ€ltlicher Zuchtprodukte unter Öko-Bedingungen zu verringern. Das Konzept muss eine praktikable Datenerfassung gewĂ€hrleisten. Ein geeignetes und kostengĂŒnstig durchfĂŒhrbares Versuchsdesign zur Ermittlung der durchschnittlichen Eignung von LegehennenherkĂŒnften fĂŒr die ökologische Haltung muss dazu entwickelt werden

    The Estimation of the Effective Centre of Mass Energy in q-qbar-gamma Events from DELPHI

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    The photon radiation in the initial state lowers the energy available for the e+^+e−^- collisions; this effect is particularly important at LEP2 energies (above the mass of the Z boson). Being aligned to the beam direction, such initial state radiation is mostly undetected. This article describes the procedure used by the DELPHI experiment at LEP to estimate the effective centre-of-mass energy in hadronic events collected at energies above the Z peak. Typical resolutions ranging from 2 to 3 GeV on the effective center-of-mass energy are achieved, depending on the event topology.Comment: 12 pages, 6 figure

    Cross-calibration of the Siemens mMR:easily acquired accurate PET phantom measurements, long-term stability and reproducibility

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    BACKGROUND: We present a quick and easy method to perform quantitatively accurate PET scans of typical water-filled PET plastic shell phantoms on the Siemens Biograph mMR PET/MR system. We perform regular cross-calibrations (Xcal) of our PET systems, including the PET/MR, using a Siemens mCT water phantom. LONG-TERM STABILITY: The mMR calibration stability was evaluated over a 3-year period where 54 cross-calibrations were acquired, showing that the mMR on average underestimated the concentration by 16 %, consistently due to the use of MR-based ÎŒ-maps. The mMR produced the narrowest calibration ratio range with the lowest standard deviation, implying it is the most stable of the six systems in the study over a 3-year period. MMR ACCURACY WITH PREDEFINED ÎŒ-MAPS: With the latest mMR software version, VB20P, it is possible to utilize predefined phantom ÎŒ-maps. We evaluated both the system-integrated, predefined ÎŒ-map of the long mMR water phantom and our own user-defined CT-based ÎŒ-map of the mCT water phantom, which is used for cross-calibration. For seven scans, which were reconstructed with correctly segmented ÎŒ-maps, the mMR produced cross-calibration ratios of 1.00–1.02, well within the acceptance range [0.95–1.05], showing high accuracy. CONCLUSIONS: The mMR is the most stable PET system in this study, and the mean underestimation is no longer an issue with the easily accessible ÎŒ-map, which resulted in correct cross-calibration ratios in all seven tests. We will share the user-defined ÎŒ-map of the mCT phantom and the protocol with interested mMR users

    Article ID 932564

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    Abstract Quality in its contemporary incarnation is commonly referred to as organizational excellence, enterprise excellence, business excellence, or performance excellence. While technology may serve as a key enabler of enterprise excellence, enterprise excellence itself is in large enabled by the human dimension both in terms of ideation and effort. The human dimension manifests in many ways, with people-centered innovation representing a critical intersection of the market environment and the enterprise's human capital or the individual inventor. Innovation in all its faces and forms can be more effectively and strategically attained through collaboration that extends throughout the enterprise, to its supply chain, and ultimately to the marketplace itself, that is, cooperation between the enterprise and the culture(s) it serves via the process of co-creation. Understanding of, sensitivity to, and leverage of culture as broadly construed is an underdeveloped aspect enterprise excellence. As considered herein, innovation contributes to enterprise excellence through conscious and customer-centric collaboration between the enterprise and the culture. As such we explore intersections among cultural anthropology, innovation, and enterprise excellence by more thoughtfully elaborating the interface between the enterprise and the customer (user) culture, including society

    Prevalence and tracking of back pain from childhood to adolescence

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    <p>Abstract</p> <p>Background</p> <p>It is generally acknowledged that back pain (BP) is a common condition already in childhood. However, the development until early adulthood is not well understood and, in particular, not the individual tracking pattern. The objectives of this paper are to show the prevalence estimates of BP, low back pain (LBP), mid back pain (MBP), neck pain (NP), and care-seeking because of BP at three different ages (9, 13 and15 years) and how the BP reporting tracks over these age groups over three consecutive surveys.</p> <p>Methods</p> <p>A longitudinal cohort study was carried out from the years of 1997 till 2005, collecting interview data from children who were sampled to be representative of Danish schoolchildren. BP was defined overall and specifically in the three spinal regions as having reported pain within the past month. The prevalence estimates and the various patterns of BP reporting over time are presented as percentages.</p> <p>Results</p> <p>Of the 771 children sampled, 62%, 57%, and 58% participated in the three back surveys and 34% participated in all three. The prevalence estimates for children at the ages of 9, 13, and 15, respectively, were for BP 33%, 28%, and 48%; for LBP 4%, 22%, and 36%; for MBP 20%, 13%, and 35%; and for NP 10%, 7%, and 15%. Seeking care for BP increased from 6% and 8% at the two youngest ages to 34% at the oldest. Only 7% of the children who participated in all three surveys reported BP each time and 30% of these always reported no pain. The patterns of development differed for the three spinal regions and between genders. Status at the previous survey predicted status at the next survey, so that those who had pain before were more likely to report pain again and vice versa. This was most pronounced for care-seeking.</p> <p>Conclusion</p> <p>It was confirmed that BP starts early in life, but the patterns of onset and development over time vary for different parts of the spine and between genders. Because of these differences, it is recommended to report on BP in youngsters separately for the three spinal regions, and to differentiate in the analyses between the genders and age groups. Although only a small minority reported BP at two or all three surveys, tracking of BP (particularly NP) and care seeking was noted from one survey to the other. On the positive side, individuals without BP at a previous survey were likely to remain pain free at the subsequent survey.</p

    Determinants of Acceptance of Cervical Cancer Screening in Dar es Salaam, Tanzania.

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    To describe how demographic characteristics and knowledge of cervical cancer influence screening acceptance among women living in Dar es Salaam, Tanzania. Multistage cluster sampling was carried out in 45 randomly selected streets in Dar es Salaam. Women between the ages of 25-59 who lived in the sampled streets were invited to a cervical cancer screening; 804 women accepted and 313 rejected the invitation. Information on demographic characteristics and knowledge of cervical cancer were obtained through structured questionnaire interviews. Women aged 35-44 and women aged 45-59 had increased ORs of 3.52 and 7.09, respectively, for accepting screening. Increased accepting rates were also found among single women (OR 2.43) and among women who had attended primary or secondary school (ORs of 1.81 and 1.94). Women who had 0-2 children were also more prone to accept screening in comparison with women who had five or more children (OR 3.21). Finally, knowledge of cervical cancer and awareness of the existing screening program were also associated with increased acceptance rates (ORs of 5.90 and 4.20). There are identifiable subgroups where cervical cancer screening can be increased in Dar es Salaam. Special attention should be paid to women of low education and women of high parity. In addition, knowledge and awareness raising campaigns that goes hand in hand with culturally acceptable screening services will likely lead to an increased uptake of cervical cancer screening
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