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X-ray microscopy is a field that has developed rapidly in recent years. Two different approaches have been used. Zone plates have been employed to produce focussed beams with sizes as low as 0.07 pm for x-ray energies below 1 keV. Images of biological materials and elemental maps for major and minor low Z have been produced using above and below absorption edge differences. At higher energies collimators and focussing mirrors have been used to make small diameter beams for excitation of characteristic K— or L-x rays of all elements in the periodic
Health and social care face growing and conflicting pressures: mounting complex needs of an ageing population, restricted funding and a workforce recruitment and retention crisis. In response, in the UK the NHS Long Term Plan promises increased investment and an emphasis on better ‘integrated’ care. We describe key aspects of integration that need addressing.
Declaration of interest
D.K.T. and S.S.S. are on the editorial board of the British Journal of Psychiatry and executives of the Academic Faculty at the Royal College of Psychiatrists. A.J.B.J., H.P. and Z.M. have roles at the Royal College of Psychiatrists that include evaluation of integrated care systems. A.J.B.J. is married to Dr Sarah Wollaston, Member of Parliament for Totnes and Chair of the Health Select Committee.
There is a need to improve geographical and financial access to healthy foods for limited resource populations in rural areas. Community Supported Agriculture (CSA) programs can improve access to healthy foods in rural and limited-resource populations. However, research is needed to discern the most appealing conditions for a CSA (e.g. price, frequency, food quantity) among rural, low-income customers. The goal of this study was to understand low-income consumers' preferences related to participation in a CSA program, considering price, frequency, food quantity and accessibility (e.g. distance) conditions. A modified exploratory choice experiment exercise was embedded within in-depth interviews to examine willingness to participate in CSA under a variety of conditions among 42 low-income adults with at least one child in the household in North Carolina, New York, Vermont and Washington. Willingness to participate in a CSA under each condition was summed and compared across conditions. Results were stratified by race, number of children and household members and McNemar's test and Student's t-test were used to examine differences in willingness between conditions. Salient quotes were extracted to support themes related to each condition. Our analysis suggests that the ideal CSA would be a full-sized share of eight to nine items of mixed variety, distributed every other week, priced at less than US$15, no more than 10 min further than the supermarket (SM) from their home and preferably less expensive but no more than 20% more expensive than SM prices. CSAs interested in reaching rural low-income populations may benefit from considering these consumer-level preferences.
Herbicide resistance is ‘wicked’ in nature; therefore, results of the many educational efforts to encourage diversification of weed control practices in the United States have been mixed. It is clear that we do not sufficiently understand the totality of the grassroots obstacles, concerns, challenges, and specific solutions needed for varied crop production systems. Weed management issues and solutions vary with such variables as management styles, regions, cropping systems, and available or affordable technologies. Therefore, to help the weed science community better understand the needs and ideas of those directly dealing with herbicide resistance, seven half-day regional listening sessions were held across the United States between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide resistance management. The major goals of the sessions were to gain an understanding of stakeholders and their goals and concerns related to herbicide resistance management, to become familiar with regional differences, and to identify decision maker needs to address herbicide resistance. The messages shared by listening-session participants could be summarized by six themes: we need new herbicides; there is no need for more regulation; there is a need for more education, especially for others who were not present; diversity is hard; the agricultural economy makes it difficult to make changes; and we are aware of herbicide resistance but are managing it. The authors concluded that more work is needed to bring a community-wide, interdisciplinary approach to understanding the complexity of managing weeds within the context of the whole farm operation and for communicating the need to address herbicide resistance.
Seven half-day regional listening sessions were held between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide-resistance management. The objective of the listening sessions was to connect with stakeholders and hear their challenges and recommendations for addressing herbicide resistance. The coordinating team hired Strategic Conservation Solutions, LLC, to facilitate all the sessions. They and the coordinating team used in-person meetings, teleconferences, and email to communicate and coordinate the activities leading up to each regional listening session. The agenda was the same across all sessions and included small-group discussions followed by reporting to the full group for discussion. The planning process was the same across all the sessions, although the selection of venue, time of day, and stakeholder participants differed to accommodate the differences among regions. The listening-session format required a great deal of work and flexibility on the part of the coordinating team and regional coordinators. Overall, the participant evaluations from the sessions were positive, with participants expressing appreciation that they were asked for their thoughts on the subject of herbicide resistance. This paper details the methods and processes used to conduct these regional listening sessions and provides an assessment of the strengths and limitations of those processes.
To examine perspectives on food access among low-income families participating in a cost-offset community-supported agriculture (CO-CSA) programme.
Farm Fresh Foods for Healthy Kids (F3HK) is a multicentre randomized intervention trial assessing the effect of CO-CSA on dietary intake and quality among children from low-income families. Focus groups were conducted at the end of the first CO-CSA season. Participants were interviewed about programme experiences, framed by five dimensions of food access: availability, accessibility, affordability, acceptability and accommodation. Transcribed data were coded on these dimensions plus emergent themes.
Nine communities in the US states of New York, North Carolina, Washington and Vermont.
Fifty-three F3HK adults with children.
CSA models were structured by partner farms. Produce quantity was abundant; however, availability was enhanced for participants who were able to select their own produce items. Flexible CSA pick-up times and locations made produce pick-up more accessible. Despite being affordable to most, payment timing was a barrier for some. Unfamiliar foods and quick spoilage hindered acceptability through challenging meal planning, despite accommodations that included preparation advice.
Although CO-CSA may facilitate increased access to fruits and vegetables for low-income families, perceptions of positive diet change may be limited by the ability to incorporate share pick-up into regular travel patterns and meal planning. Food waste concerns may be particularly acute for families with constrained resources. Future research should examine whether CO-CSA with flexible logistics and produce self-selection are sustainable for low-income families and CSA farms.
The study objective was to determine the prevalence of Staphylococcus aureus colonisation in the nares and oropharynx of healthy persons and identify any risk factors associated with such S. aureus colonisation. In total 263 participants (177 adults and 86 minors) comprising 95 families were enrolled in a year-long prospective cohort study from one urban and one rural county in eastern Iowa, USA, through local newspaper advertisements and email lists and through the Keokuk Rural Health Study. Potential risk factors including demographic factors, medical history, farming and healthcare exposure were assessed. Among the participants, 25.4% of adults and 36.1% minors carried S. aureus in their nares and 37.9% of adults carried it in their oropharynx. The overall prevalence was 44.1% among adults and 36.1% for minors. Having at least one positive environmental site for S. aureus in the family home was associated with colonisation (prevalence ratio: 1.34, 95% CI: 1.07–1.66). The sensitivity of the oropharyngeal cultures was greater than that of the nares cultures (86.1% compared with 58.2%, respectively). In conclusion, the nares and oropharynx are both important colonisation sites for healthy community members and the presence of S. aureus in the home environment is associated with an increased probability of colonisation.
The Vulnerable snow leopard Panthera uncia experiences persecution across its habitat in Central Asia, particularly from herders because of livestock losses. Given the popularity of snow leopards worldwide, transferring some of the value attributed by the international community to these predators may secure funds and support for their conservation. We administered contingent valuation surveys to 406 international visitors to the Annapurna Conservation Area, Nepal, between May and June 2014, to determine their willingness to pay a fee to support the implementation of a Snow Leopard Conservation Action Plan. Of the 49% of visitors who stated they would pay a snow leopard conservation fee in addition to the existing entry fee, the mean amount that they were willing to pay was USD 59 per trip. The logit regression model showed that the bid amount, the level of support for implementing the Action Plan, and the number of days spent in the Conservation Area were significant predictors of visitors’ willingness to pay. The main reasons stated by visitors for their willingness to pay were a desire to protect the environment and an affordable fee. A major reason for visitors’ unwillingness to pay was that the proposed conservation fee was too expensive for them. This study represents the first application of economic valuation to snow leopards, and is relevant to the conservation of threatened species in the Annapurna Conservation Area and elsewhere.
Nine species of the gall-associated doryctine genus Allorhogas Gahan (Hymenoptera: Braconidae) are described from Brazil (A. clidemiae Martínez and Zaldívar-Riverón new species, A. granivorus Zaldívar-Riverón and Martínez new species, A. mineiro Zaldívar-Riverón and Martínez new species, and A. vulgaris Zaldívar-Riverón and Martínez new species) and Costa Rica (A. brevithorax Zaldívar-Riverón and Martínez new species, A. pallidus Martínez and Zaldívar-Riverón new species, A. psychotria Zaldívar-Riverón and Martínez new species, A. punctatus Martínez and Zaldívar-Riverón new species, and A. tico Martínez and Zaldívar-Riverón new species). We provide host plant records for the described species, including information that reveals that at least three of them feed on seeds. Allorhogas granivorus had previously been confirmed to represent a natural enemy of the invasive weed Miconia calvescens de Candolle (Melastomataceae). Updated keys to the species of Allorhogas from Brazil and Costa Rica are provided.
Using the finite-element we have modeled the stress field near the calving face of an idealized tidewater glacier under a variety of assumptions about submarine calving-face height, subaerial calving-face height, and ice rheology. These simulations all suggest that a speed maximum should be present at the calving face near the waterline. In experiments without crevassing, the decrease in horizontal velocity above this maximum culminates in a zone of longitudinal compression at the surface somewhat up-glacier from the face. This zone of compression appears to be a consequence of the non-linear rheology of ice. It disappears when a linear rheology is assumed. Explorations of the near-surface stress field indicate that when pervasive crevassing of the surface ice is accounted for in the simulations (by rheological softening), the zone of compressive strain rates does not develop. Variations in the pattern of horizontal velocity with glacier thickness support the contention that calving rates should increase with water depth at the calving face. In addition, the height of the subaerial calving face may have an importance that is not visible in current field data owing to the lack of variation in height of such faces in nature. Glaciers with lower calving faces may not have sufficient tensile stress to calve actively, while tensile stresses in simulated higher faces are sufficiently high that such faces will be unlikely to build in nature.
Proper motion surveys offer a great deal of data bearing on important astronomical problems such as stellar kinematics and the luminosity function in the solar neighborhood. Major obstacles to the full use of proper motions have long been posed by: (1) incompleteness of proper motion surveys, (2) proper motion bias in kinematic studies, and (3) the indirect approaches and kinematical assumptions needed in traditional luminosity studies.
This paper reports the first results of solar motion and galactic rotation studies which are being done at Lick Observatory, using the new data from the Lick Northern Proper Motion (NPM) Program. This study finds: (1) A = +11.31 ± 1.06 and B = −13.91 ± 0.92 km/s/kpc, consistent with a nearly flat galactic rotation curve with a local circular velocity near 200 km/s; (2) solar apex locations lying near the standard apex for low galactic latitudes, but trending strongly toward the direction of galactic rotation for high galactic latitudes; (3) RMS external error estimates for the Lick proper motions: for the absolute zero-point in a typical NPM field, and for the overall systematic zero-point error. A more detailed presentation of these results has been given by Hanson (1987). The NPM program is reviewed in another paper in this Symposium, and has been described in detail by Klemola, Jones, and Hanson (1987).
This paper reviews the Lick Northern Proper Motion (NPM) program, describing its goals, organization, and methods, summarizing its progress, and outlining the work remaining for the future. The first phase of the NPM program (outside the Milky Way) is now nearing completion. A detailed description of the NPM program has been given by Klemola, Jones, and Hanson (1987). Recent results using the NPM data in a study of solar motion and galactic rotation are presented in a separate paper in this Symposium.
Two examples of anionic complexes having vapochromic behavior are investigated: [K(H2O)][Pt(ppy)(CN)2] “Pt(ppy)” and [K(H2O)][Pt(bzq)(CN)2] “Pt(bzq)”, where ppy = 2-phenylpyridinate and bzq = 7,8-benzoquinolate. These monohydrate-potassium salts exhibit a change in color from purple to yellow [Pt(ppy)] and from red to yellow [Pt(bzq)] upon heating to 110 °C, and they transform back into the original color upon absorption of water molecules from the environment. Available only in the form of polycrystalline samples, no structural information on such compounds is accessible, due to highly overlapping peaks in powder diffraction profiles. We use in situ Pair Distribution Function measurements on powder samples to investigate the dynamics of the structural changes induced by temperature variations. By means of a multivariate approach, we were able to extract dynamic structural information from collected profiles without using prior knowledge on the static crystal structure of the compounds. The critical temperature and the characteristics of the vapochromic transition have been identified, as well as the main structural changes causing it.
Adverse psychosocial working environments characterized by job strain (the combination of high demands and low control at work) are associated with an increased risk of depressive symptoms among employees, but evidence on clinically diagnosed depression is scarce. We examined job strain as a risk factor for clinical depression.
We identified published cohort studies from a systematic literature search in PubMed and PsycNET and obtained 14 cohort studies with unpublished individual-level data from the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) Consortium. Summary estimates of the association were obtained using random-effects models. Individual-level data analyses were based on a pre-published study protocol.
We included six published studies with a total of 27 461 individuals and 914 incident cases of clinical depression. From unpublished datasets we included 120 221 individuals and 982 first episodes of hospital-treated clinical depression. Job strain was associated with an increased risk of clinical depression in both published [relative risk (RR) = 1.77, 95% confidence interval (CI) 1.47–2.13] and unpublished datasets (RR = 1.27, 95% CI 1.04–1.55). Further individual participant analyses showed a similar association across sociodemographic subgroups and after excluding individuals with baseline somatic disease. The association was unchanged when excluding individuals with baseline depressive symptoms (RR = 1.25, 95% CI 0.94–1.65), but attenuated on adjustment for a continuous depressive symptoms score (RR = 1.03, 95% CI 0.81–1.32).
Job strain may precipitate clinical depression among employees. Future intervention studies should test whether job strain is a modifiable risk factor for depression.
This paper briefly describes the principle of operation and science goals of the AMANDA high energy neutrino telescope located at the South Pole, Antarctica. Results from an earlier phase of the telescope, called AMANDA-BIO, demonstrate both reliable operation and the broad astrophysical reach of this device, which includes searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, Gamma-Ray Bursts and diffuse sources. The predicted sensitivity and angular resolution of the telescope were confirmed by studies of atmospheric muon and neutrino backgrounds. We also report on the status of the analysis from AMANDA-II, a larger version with far greater capabilities. At this stage of analysis, details of the ice properties and other systematic uncertainties of the AMANDA-II telescope are under study, but we have made progress toward critical science objectives. In particular, we present the first preliminary flux limits from AMANDA-II on the search for continuous emission from astrophysical point sources, and report on the search for correlated neutrino emission from Gamma Ray Bursts detected by BATSE before decommissioning in May 2000. During the next two years, we expect to exploit the full potential of AMANDA-II with the installation of a new data acquisition system that records full waveforms from the in-ice optical sensors.
In this study, the development of a boundary layer past a change in surface roughness (from rough to smooth,
) is examined. Measurements of the flow were made by hot wires, whereas the friction velocity was estimated by Preston tube measurements. By means of a diagnostic plot of the turbulence intensity, it is shown that above the internal layer the flow exhibits characteristics of a rough, wall-bounded flow, whereas near the wall the turbulence intensity is similar to that of an isolated smooth wall. Similarly, viscous scaling of the mean streamwise velocity shows an excessive wake region downstream of the
wall surface change that diminishes with the fetch from the surface change. Above the internal layer a second peak in the streamwise Reynolds stress was associated with the upstream rough-wall flow. Examination of the turbulent spectra revealed the presence of large-scale motions within this region that gradually diminish in strength with increasing distance from the change in surface roughness. The magnitude of the near-wall peak failed to collapse to that of a comparable smooth-wall boundary layer under viscous scaling, however, the wall-normal location of the peak appears to be at
at all downstream distances. A new mixed scaling is proposed for the near-wall peak based on the corrected wake deficit and the friction velocity. This shows the importance of outer region to the growth of near-wall peak in this non-equilibrium boundary layer.
The Lick Northern Proper Motion (NPM) and the Yale-San Juan Southern Proper Motion (SPM) programs have been described on several occasions (Wright 1950; Deutsch and Klemola 1974; Vasilevskis 1973; and Wesselink 1974). The two programs represent an attempt to measure the coordinates and proper motions, with respect to the extragalactic reference frames, for large numbers of stars representing most of the astrophysically-recognized classes. The photographic plate material forming the basis of the NPM program derives from the first (1947-1954) and second (1970-present) epoch phases for 1246 fields with the Lick 51 cm Carnegie double-astrograph for centers at -20° and northward (Shane and Wirtanen 1967). A southern supplement of 144 additional fields takes the program to -30°. The SPM consists of 632 fields with centers at -20° and southward. The first epoch plates were taken between 1965 and 1974 and a partial extension of 72 fields to more northerly declinations is essentially complete. One short and one long exposure permit the measurement of positions and approximate photometry for selected stars and reference galaxies over the blue magnitude range from about 8 to 17-18.
This paper reviews recent astrometric progress in determining the Hyades cluster distance, emphasizing critical assessment of the precision and accuracy of the observations. Substantial improvement in the trigonometric parallaxes yields a mean Hyades distance modulus m - M = 3.25 ± 0.08 mag, nearly twice as precise as previous parallax results. New proper motions from three independent sources yield a mean distance modulus 3.31 ± 0.06 mag. The close agreement of the recent astrometric results suggests that the overall mean Hyades distance modulus 3.30 mag may be used with confidence in cosmic distance scale calibrations.
To assess nasal morbidity resulting from nasoseptal flap use in the repair of skull base defects in endoscopic anterior skull base surgery.
Thirty-six patients awaiting endoscopic anterior skull base surgery were prospectively recruited. A nasoseptal flap was used for reconstruction in all cases. Patients were assessed pre-operatively and 90 days post-operatively via the Sino-Nasal Outcome Test 20 questionnaire and visual analogue scales for nasal obstruction, pain, secretions and smell; endoscopic examination findings and mucociliary clearance times were also recorded.
Sino-Nasal Outcome Test 20 questionnaire data and visual analogue scale scores for pain, smell and secretions showed no significant differences between pre- and post-operative outcomes, with visual analogue scale scores for nasal obstruction actually showing a significant improvement (p = 0.0007). A significant deterioration for both flap and non-flap sides was demonstrated post-operatively on endoscopic examination (p = 0.002 and p = 0.02 respectively).
Whilst elevation of a nasoseptal flap in endoscopic surgery of the anterior skull base engendered significant clinical deterioration on examination post-operatively, quality of life outcomes showed that no such deterioration was subjectively experienced by the patient. In fact, there was significant nasal airway improvement following nasoseptal flap reconstruction.