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Stictococcus vayssierei is a major pest of root and tuber crops in central Africa. However, data on its ecology are lacking. Here we provide an updated estimate of its distribution with the aim of facilitating the sustainable control of its populations. Surveys conducted in nine countries encompassing 13 ecological regions around the Congo basin showed that African root and tuber scale was present in Cameroon, Central African Republic, Congo, Democratic Republic of Congo, Equatorial Guinea, Gabon and Uganda. It was not found on the sites surveyed in Chad and Nigeria. The pest occurred in the forest and the forest-savannah mosaic as well as in the savannah where it was never recorded before. However, prevalence was higher in the forest (43.1%) where cassava was the most infested crop, compared to the savannah (9.2%) where aroids (cocoyam and taro) were the most infested crops. In the forest habitat, the pest was prevalent in all but two ecological regions: the Congolian swamp forests and the Southern Congolian forest-savanna mosaic. In the savannah habitat, it was restricted to the moist savannah highlands and absent from dry savannahs. The scale was not observed below 277 m asl. Where present, the scale was frequently (87.1% of the sites) attended by the ant Anoplolepis tenella. High densities (>1000 scales per plant) were recorded along the Cameroon–Gabon border. Good regulatory measures within and between countries are required to control the exchange of plant materials and limit its spread. The study provides information for niche modeling and risk mapping.
Large, ‘complex’ pre-Neolithic hunter-gatherer communities thrived in southern China and northern Vietnam, contemporaneous with the expansion of farming. Research at Con Co Ngua in Vietnam suggests that such hunter-gatherer populations shared characteristics with early farming communities: high disease loads, pottery, complex mortuary practices and access to stable sources of carbohydrates and protein. The substantive difference was in the use of domesticated plants and animals—effectively representing alternative responses to optimal climatic conditions. The work here suggests that the supposed correlation between farming and a decline in health may need to be reassessed.
Preparing investigators to competently conduct community-engaged research is critical to achieving Clinical and Translational Science Award (CTSA) program goals. The purpose of this study is to describe the perspectives of members of a long-standing community engagement advisory board (CEAB) on investigators’ readiness to engage communities and indicators of investigator competence in community-engaged research, in order to suggest core competencies to guide the development of CTSA-sponsored educational programs. Two 90-minute focus groups were conducted with a subset of members of a CEAB (n=19) affiliated with the Center for Clinical and Translational Science at the University of Illinois at Chicago. CEAB members identified a range of investigator skills and practices that demonstrate readiness to engage in community-engaged research. Eight competencies were identified that should be incorporated in providing education to enhance the readiness and competency of CTSA-affiliated researchers planning to engage communities in research. CEAB observations demonstrate the necessity of developing competency-based educational programs that prepare clinical and translational scientists at all levels for the important work of community-engaged research.
Community engagement is deemed as critical to the success of the CTSA program. In 2009, to improve research engagement and build capacity for community-engaged research across the translational spectrum, the Center for Clinical and Translational Science at the University of Illinois at Chicago created a Community Engagement Advisory Board (CEAB). Here, we report results of our ongoing evaluation efforts.
CEAB activities are evaluated using mixed methods. Annual CEAB evaluation surveys were completed from 2010 to 2016 (n=106 respondents). In 2014, two 90-minute focus groups were conducted with a subset of recent CEAB members (n=19).
Survey data suggest respondents perceive their consultations to be helpful in improving the capacity of researchers (90%) and the quality of research projects (80%). Further, CEAB members perceive themselves to have personally benefitted from their involvement including obtaining new knowledge (84%), expansion of their networks (76%), and forming new community linkages (51%). Results of the qualitative data were consistent with survey data.
Our CEAB has improved research engagement and developed institutional capacity to conduct community-engaged research in several ways. Our findings can inform the establishment or enhancement of community engagement services for CTSA-affiliated researchers and community partners.
The purpose of this study was to obtain feedback from a diverse group of community advisory board members about different clinic or hospital-based approaches to increasing research participation.
Members of an established community engagement advisory board (n=16) provided qualitative and survey data regarding attitudes and preferences for 3 hospital and clinic system strategies to recruit patients into clinical research including universal consent for research, patient registries, and patient portals.
Overall, there was moderate support for each of the 3 approaches discussed. Board members described advantages and disadvantages of each method. Based on the qualitative data, universal consent was viewed as the best strategy for consenting high volumes of patients for research. However, patient registries and portals were seen as more acceptable, less-intrusive and more likely to result in higher participation rates. Survey data were consistent with qualitative findings.
Input from community stakeholders is needed to identify strategies to enhance participation and increase diversity in clinical research. Members of our CEAB identified patient registries and portals as feasible and nonintrusive approaches to increasing research participation. Additional research is needed to confirm these findings and to establish best practices for supporting patients in using registry approaches.
The purpose of this paper is to describe the formation, operation, and evaluation of a Community Engagement Advisory Board (CEAB) that serves as a resource of the University of Illinois at Chicago’s (UIC) Center for Clinical and Translational Sciences (CCTS).
Current CEAB roles and functions, operating procedures for research consultations and program evaluation strategies were described. Investigators receiving a consultation from 2009 to 2017 (n=91, response rate 78%) were surveyed via an online survey immediately after the consultation and at 12-month follow-up.
Overall, CEAB members were viewed as having sufficient information (92%) and expertise (79%) to provide consultation. Satisfaction levels with the specific consultation received and the overall consultation service were high. The majority of investigators indicated that they would come back to the CEAB for a future consultation, if needed, and would recommend a consultation to others (93% and 96%, respectively). At 12-months, 87% of respondents indicated they had implemented at least some of the recommendations received and 93% said that the consultation influenced their subsequent research.
Data from recent annual evaluations highlight the benefits of CEAB for consulting investigators. Our model can be used to inform the development of future CEAB boards.
The chaotic dynamics of low-dimensional systems, such as Lorenz or Rössler flows, is guided by the infinity of periodic orbits embedded in their strange attractors. Whether this is also the case for the infinite-dimensional dynamics of Navier–Stokes equations has long been speculated, and is a topic of ongoing study. Periodic and relative periodic solutions have been shown to be involved in transitions to turbulence. Their relevance to turbulent dynamics – specifically, whether periodic orbits play the same role in high-dimensional nonlinear systems like the Navier–Stokes equations as they do in lower-dimensional systems – is the focus of the present investigation. We perform here a detailed study of pipe flow relative periodic orbits with energies and mean dissipations close to turbulent values. We outline several approaches to reduction of the translational symmetry of the system. We study pipe flow in a minimal computational cell at
, and report a library of invariant solutions found with the aid of the method of slices. Detailed study of the unstable manifolds of a sample of these solutions is consistent with the picture that relative periodic orbits are embedded in the chaotic saddle and that they guide the turbulent dynamics.
Objectives: Careful characterization of how functional decline co-evolves with cognitive decline in older adults has yet to be well described. Most models of neurodegenerative disease postulate that cognitive decline predates and potentially leads to declines in everyday functional abilities; however, there is mounting evidence that subtle decline in instrumental activities of daily living (IADLs) may be detectable in older individuals who are still cognitively normal. Methods: The present study examines how the relationship between change in cognition and change in IADLs are best characterized among older adults who participated in the ACTIVE trial. Neuropsychological and IADL data were analyzed for 2802 older adults who were cognitively normal at study baseline and followed for up to 10 years. Results: Findings demonstrate that subtle, self-perceived difficulties in performing IADLs preceded and predicted subsequent declines on cognitive tests of memory, reasoning, and speed of processing. Conclusions: Findings are consistent with a growing body of literature suggesting that subjective changes in everyday abilities can be associated with more precipitous decline on objective cognitive measures and the development of mild cognitive impairment and dementia. (JINS, 2018, 24, 104–112)
The star SK 80 in the SMC is classified as 07Iaf by Walborn (1976) who notes that it is the only confirmed Of star in that Galaxy known to date. A knowledge of the mass loss properties of OB stars in the Magellanic Clouds is of interest because of the recent evidence that such stars show reduced mass loss properties than their galactic counterparts (Hutchings 1980) and for Of stars because of the possible link between such stars and Pop I transition WNL stars (Conti 1976).
We have secured HIRES IUE and optical spectra of SK 80 and have attempted to derive the mass loss rate from these data.
The Siwalik fluvial deposits of Pakistan are characterized by varying proportions of red to brown silts, fine sands, and minor clays representing overbank deposition. In the Chinji Formation (~15–10.5 Ma), floodplain facies consist of overlapping packages of: 1) well-bedded siltstones and occasional sheet sands or small channel sands, 2) an overlying transitional zone with increased bioturbation and minor pedogenesis, 3) a capping paleosol. These packages are 5–6 m thick and pinch out laterally over 1–2 km; they appear to represent crevasse-splay lobes that aggraded rapidly into low-lying wet areas and then became stable land surfaces. The cycle was repeated as aggradation of the major rivers and/or local subsidence transformed the topographic highs into lows where sedimentation again buried soil surfaces. Floodplains in the Nagri Formation (~10.5–9 Ma) were associated with a larger channel system and were less complex, and those of the Dhok Pathan Formation (~9–6 Ma) were influenced by several contemporaneous river systems and again became more complex.
Paleosols are superimposed on all lithofacies and occur every 4–10 m thoughout the 3500 m sequence where overbank deposits are dominant. Paleomagnetic calibration of the Siwalik sequence indicates that paleosols represent 10–50K yrs, on average. Individual paleosols are red-orange or red-brown, 1.6–4.8 m thick, have abundant evidence of bioturbation, ped structure, clay cutans and a zone depleted in matrix carbonate above a lower zone with carbonate precipitates. A long-term record of Siwalik vegetation in Pakistan is contained in the carbon isotope ratios of paleosol carbonate. There is no evidence that paleosols varied in maturity with distance from the major channels; instead vertical and lateral facies relationships were controlled by shifting crevasse-splay lobes and overbank channels.
The processes of overbank sedimentation in the Siwalik sequence have important consequences for preservation of vertebrate faunas. Most of the 800+ fossil localities occur in channel fills within overbank facies; relatively few are associated with paleosols or the coarse deposits of major channels. The frequency of overbank channel fills varies through the different formations, resulting in uneven sampling of the vertebrate faunas. Most skeletal remains are attritrional, and bones are disassociated and fragmentary but otherwise well-preserved. This is partly a consequence of bioturbation and minor transport followed by rapid burial within the abandoned channels. The ecological setting of the Siwalik biota was controlled by a mosaic of floodplain environments that changed in complexity through time. In contrast to the Eocene Bighorn Basin floodplains, there was no simple lateral relationship of habitat types with distance from the major channels.
We provide a high-resolution map of elevation change rates at the Juneau Icefield (JIF), southeastern Alaska, in order to quantify its contribution to sea-level rise between 2000 and 2009/2013. We also produce the first high-resolution map of ice speeds at the JIF, which we use to constrain flux and look for acceleration. We calculate using stacked digital elevation models (DEMs) from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument and the Shuttle Radar Topography Mission (SRTM), taking into account SRTM C-band penetration via comparison with SRTM X-band elevations. Overall, the JIF is losing mass less rapidly (0.13 ± 0.12 m w.e. a–1) than other Alaskan icefields (0.79 m w.e. a–1). We determine glacier speeds using pixel-tracking on optical image pairs acquired from 2001 to 2010 by ASTER, from radar image pairs acquired between 2007 and 2011 and from radar interferometry in 1995. We detect seasonal speed variations but no interannual acceleration, ruling out dynamics as the cause of the observed thinning. Thinning must therefore be due to the documented warming in the region. Flux measurements confirm this for Mendenhall Glacier, showing that calving constitutes only 2.5–5% of mass loss there.
Late-summer subglacial water pressures have been measured in a dense array of boreholes in the ablation area of Haut Glacier d’Arolla, Switzerland. Interpolated surfaces of minimum diurnal water pressure and diurnal water-pressure variation suggest the presence of a subglacial channel within a more widespread, distributed drainage system. The channel flows along the centre of a variable pressure axis (VPA), some tens of metres wide, that is characterized by low minimum diurnal water pressures (frequently atmospheric) and high diurnal water-pressure variations. These characteristics are transitional over a lateral distance of c. 70 m to higher and more stable subglacial water pressures in the adjacent distributed system. Water-pressure variations recorded in boreholes located close to the centre of the VPA reflect the delivery of surface-derived meltwater to the glacier bed and result in a diurnally reversing, transverse hydraulic gradient that drives water out from the channel into the distributed system during the afternoon and back to the channel overnight. Subglacial observations suggest that such flow occurs through a vertically confined sediment layer. Borehole turbidity records indicate that the resulting diurnal water flows are responsible for the mobilization and transport of fine debris in suspension. Analysis of the propagation velocity and amplitude attenuation cf the diurnal pressure waves suggests that the hydraulic conductivity of the sediment layer decreases exponentially with distance from the channel, falling from c. 10−4 m s−1 at the channel boundary to c. 10−7 m s−1 70 m away. These apparent hydraulic conductivities are consistent with Darcian flow through clean sand and typical glacial till, respectively.
We suggest that fine material is systematically flushed from basal sediments located adjacent to large, melt-season drainage channels beneath warm-based glaciers. This process may have important implications for patterns of glacier erosion, hydro-chemistry and dynamics.
We present an age-structured mathematical model of malaria and pneumonia to study the effect of two capacity-building interventions: Integrated Management of Infectious Diseases (IMID) and On-site Support Services (OSS). IMID leads to a reduction in malaria prevalence by more than 2·4% across the [0,5), [5,14) and [14,50) age groups. IMID + OSS reduces it by more than 16·0% across all age groups. IMID decreases pneumonia prevalence by more than 3·0% across all age groups while IMID + OSS decreases it by more than 1·0% across all age groups. The number of malaria and pneumonia deaths is reduced by 7·8% by IMID across all age groups and IMID + OSS decreases this number by 30·5% across all age groups, which translates to saving a life of a child per month. Prevalence of malaria-pneumonia for the [0,5) age group is 0·52% at baseline, and IMID and IMID + OSS reduce it by 6·6% and 23·6%, respectively. There is no change in incidence of malaria or pneumonia disease episodes. The results also indicate that triaging of children contributes more than 50% to the effect of the interventions in reduction of deaths and a range of 14–91% in reduction of disease cases.
Considerable attention has been focussed in recent years upon the validity of the radiocarbon dating method by papers whose authors have considered that one or other of the fundamental principles might either be in error or require serious modification (Crowe, 1958; Milojčić, 1957; Elsasser, Ney, and Winkler, 1957; Daniel, 1959). It has even been suggested that errors as great as 800 years might arise between datings on the same sample made in different laboratories (Crowe, 1958). In the light of such criticism, it is clearly of the utmost importance to investigate, and, if possible, justify the basic assumptions on which the validity of the method rests.
A technique for 14C measurement of small volume (0.5L) oceanic water samples by Accelerator Mass Spectrometry (AMS) is described. Samples were taken from a CTD/rosette system used for standard hydrographic work. After CO2 extraction and target preparation, the samples were measured at the Zürich tandem accelerator facility. On the basis of 14C data from samples collected on a station in the northern Weddell Sea, the precision of the measurements is estimated to ca ±8‰. The error in the present AMS results is dominated by the statistical error in 14C detection. From results of duplicate targets, it is concluded that a precision of ±5° can be reached. The 14C data are discussed in relation to the Weddell Sea hydrography.
FUSE1 observations of stellar wind variability in the LMC supergiant Sk–67°166 (O4 If+)
In the framework of our high-frequency survey of giant radio galaxies with the Effelsberg 100-m telescope (Klein et al., 1994; Saripalli et al., 1995) we have obtained radio continuum maps of NGC6251, a source of 1.5 Mpc size (H0 = 75km s–1Mpc–1). Together with low-frequency WSRT observations (Willis & O'Dea, 1990), these measurements form a unique data base which for the first time allows thorough studies of the spectral index over a large frequency range. Theoretical models of particle ageing have been fitted to the spectrum to determine particle ages and other relevant physical parameters. Because of the immense size of NGC6251 these numbers provide information about the physics of the surrounding intergalactic medium.