Relationship Between Fruit Yield and Damage by Codling Moth and Plum Curculio in a Biologically-Managed Apple Orchard

Fruit yield, codling moth (Cydia pomonella) damage, and plum curculio (Conotrachelus nenuphar) damage were monitored over an 8-year period in a O.5-ha, biologically-managed apple orchard in southwestern Michigan. The relationship between yield and damage was examined for both of these pests. The orchard showed clear biennial bearing patterns of alternating high and low yields. A significant negative correlation was found for yield and percent- age damage by codling moth but not for plum curculio damage. However, the estimated amount of fruit damaged by codling moth remained relatively stable over the period, indicating that changes in percentage damage depended on yield dynamics rather than changes in codling moth abundance. In contrast, the amount of fruit damaged by plum curculio showed biennial fluctuations and a positive correlation with yield, indicating that the population of this pest was capable of responding with increased oviposition in years with greater fruit yield. In addition, a comparison of codling moth fruit injury in years with and without the use of pheromone mating disruption showed no statistically significant reduction in damage as a result of using this method, suggesting that the orchard may be too small or codling moth populations too high for effective use of this management tactic

Ecological Observations on Predatory Coccinellidae (Coleoptera) in Southwestern Michigan

Ecological observations on habitat utilization by thirteen species of predatory Coccinellidae were made at a southern Michigan site during 1989 and 1990. Most of species were common during both years and used both agricul- tural and uncultivated habitats. Coccinella septempunctata and Coleomegilla maculata, were the most abundant in agricultural crops (alfalfa, maize, soy- bean and triticale), whereas Adalia bipunctata and Cycloneda munda, were the most abundant in deciduous and bushy habitats

Observations of First Occurrence and Severity of Potato Leafhopper, \u3ci\u3eEmpoasca Fabae\u3c/i\u3e (Harris), (Homoptera: Cicadellidae) in the North Central and Eastern United States.

This paper presents available data on the first occurrence dates and the damage severity of the potato leafhopper in the north central and north eastern United States collected during the past 47 years (1951-1997). The data were collected from a variety of sources including: potato leafhopper literature review; published reports; pest alerts; pest surveys; and delphi surveys. First occurrence and severity data show that the arrival time of potato leafhopper and subsequent damage severity varies substantially from year to year. A correlation analysis between date of first occurrence and severity of damage for Michigan, Minnesota, Wisconsin, the north central region and the northeastern region indicated no significant relationship between first arrival dates and damage severity. The lack of a relationship between the time of arrival of the migrant leafhopper and severity indicate that other factors, including frequency and magnitude of arrivals, weather conditions during the growing season and crop management contribute to the eventual severity of damage caused to crops by this migratory pest. The analysis of potato leafhopper severity data showed significant differences between years. There were no significant differences in severity among states within the north central region, indicating that potato leafhopper severity is a regional phenomenon

Analysis of some global optimization algorithms for space trajectory design

In this paper, we analyze the performance of some global search algorithms on a number of space trajectory design problems. A rigorous testing procedure is introduced to measure the ability of an algorithm to identify the set of ²-optimal solutions. From the analysis of the test results, a novel algorithm is derived. The development of the novel algorithm starts from the redefinition of some evolutionary heuristics in the form of a discrete dynamical system. The convergence properties of this discrete dynamical system are used to derive a hybrid evolutionary algorithm that displays very good performance on the particular class of problems presented in this paper

Criticality for the Gehring link problem

In 1974, Gehring posed the problem of minimizing the length of two linked curves separated by unit distance. This constraint can be viewed as a measure of thickness for links, and the ratio of length over thickness as the ropelength. In this paper we refine Gehring's problem to deal with links in a fixed link-homotopy class: we prove ropelength minimizers exist and introduce a theory of ropelength criticality. Our balance criterion is a set of necessary and sufficient conditions for criticality, based on a strengthened, infinite-dimensional version of the Kuhn--Tucker theorem. We use this to prove that every critical link is C^1 with finite total curvature. The balance criterion also allows us to explicitly describe critical configurations (and presumed minimizers) for many links including the Borromean rings. We also exhibit a surprising critical configuration for two clasped ropes: near their tips the curvature is unbounded and a small gap appears between the two components. These examples reveal the depth and richness hidden in Gehring's problem and our natural extension.Comment: This is the version published by Geometry & Topology on 14 November 200

The nursing contribution to chronic disease management: a whole systems approach: Report for the National Institute for Health Research Service Delivery and Organisation programme

Background Transforming the delivery of care for people with Long Term Conditions (LTCs) requires understanding about how health care policies in England and historical patterns of service delivery have led to different models of chronic disease management (CDM). It is also essential in this transformation to analyse and critique the models that have emerged to provide a more detailed evidence base for future decision making and better patient care. Nurses have made, and continue to make, a particular contribution to the management of chronic diseases. In the context of this study, there is a particular focus on the origins of each CDM model examined, the processes by which nursing care is developed, sustained and mainstreamed, and the outcomes of each case study as experienced by service users and carers. Aims To explore, identify and characterise the origins, processes and outcomes of effective CDM models and the nursing contribution to such models using a whole systems approach Methods The study was divided into three phases: Phase 1: Systematic mapping of published and web-based literature. Phase 2: A consensus conference of nurses working within CDM. Sampling criteria were derived from the conference and selected nurses attended a follow up workshop where case study sites were identified. Phase 3: Multiple case study evaluation Sample: 7 case studies representing 4 CDM models. These were: i) public health nursing model; ii) primary care nursing model; iii) condition specific nurse specialist model; iv) community matron model. Methods: Evaluative case study design with the unit of analysis the CDM model (Yin, 2003): • semi-structured interviews with practitioners, patients, their carers, managers and commissioners • documentary analysis • psycho-social and clinical outcome data from specific conditions • children and young people: focus groups, age-specific survey tools. Benchmarking outcomes: Adults benchmarked against the Health Outcomes Data Repository (HODaR) dataset (Currie et al, 2005). Young people were benchmarked against the Health Behaviour of School aged Children Survey (Currie et al, 2008). Cost analysis: Due to limitations in the available data, a simple costing exercise was undertaken to ascertain the per patient cost of the nurse contribution to CDM in each of the models, and to explore patterns of health and social care utilisation. Analysis: A whole system methodology was used to establish the principles of CDM. i) The causal system is a “network of causal relationships” and focuses on long term trends and processes. ii) The data system recognises that for many important areas there is very little data. Where a particular explanatory factor is important but precise data are lacking, a range of methods should be employed to illuminate each factor as much as possible. iii) The organisational whole system emphasises how various parts of the health and social care system function together as a single system rather than as parallel systems. iv) The patient experience recognises that the whole system comes together and is embodied in the experience of each patient. Key findings While all the models strove to be patient centred in their implementation, all were linked at a causal level to disease centric principles of care which dominated the patient experience. Public Health Model • The users (both parents and children) experienced a well organised and coordinated service that is crossing health and education sectors. • The lead school nurse has provided a vision for asthma management in school-aged children. This has led to the implementation of the school asthma strategy, and the ensuing impacts including growing awareness, prevention of hospital admissions, confidence in schools about asthma management and healthier children. Primary Care Model • GP practices are providing planned and routine management of chronic disease, tending to focus on single diseases treated in isolation. Care is geared to the needs of the uncomplicated stable patient. • More complex cases tend to be escalated to secondary care where they may remain even after the patient has stabilised. • Patients with multiple diagnoses continue to experience difficulty in accessing services or practice that is designed to provide a coherent response to the idiosyncratic range of diseases with which they present. This is as true for secondary care as for primary care. • While the QOF system has clearly been instrumental in developing and sustaining a primary care nursing model of CDM, it has also limited the scope of the model to single diseases recordable on a register, rather than focus on patient centred care needs. Nurse Specialist Model • The model works under a disease focused system underpinned by evidence based medicine exemplified by NICE guidelines and NSF’s. • The model follows a template drawn from medicine and sustainability is significantly dependent on the championship and protectionism offered by senior medical clinicians. • A focus on self-management in LTCs gives particular impetus to nurse-led enablement of self-management. • The shift of LTC services from secondary care to primary care has often not been accompanied by a shift in expertise. Community Matron Model • The community matron model was distinctive in that it had been implemented as a top down initiative. • The model has been championed by the community matrons themselves, and the pressure to deliver observable results such as hospital admission reductions has been significant. • This model was the only one that consistently resulted in open access (albeit not 24 hours) and first point of contact for patients for the management of their ongoing condition. Survey Findings Compared to patients from our case studies those within HODaR visited the GP, practice nurse or NHS walk-in centres more, but had less home visits from nurses or social services within the six weeks prior to survey. HODaR patients also took significantly more time off work and away from normal activities, and needed more care from friends/ relatives than patients from our study within the last six weeks. The differences between the HODaR and case study patients in service use cannot easily be explained but it could be speculated when referring to the qualitative data that the case study patients are benefiting from nurse-led care. Cost analysis – The nurse costs per patient are at least ten times higher for community matrons conducting CDM than for nurses working in other CDM models. The pattern of service utilisation is consistent with the focus of the community matron role to provide intensive input to vulnerable patients. Conclusions Nurses are spearheading the kind of approaches at the heart of current health policies (Department of Health, 2008a). However, tensions in health policy and inherent contradictions in the context of health care delivery are hampering the implementation of CDM models and limiting the contribution nurses are able to make to CDM. These include: ? data systems that were incompatible and recorded patients as a disease entity ? QOF reinforced a disease centric approach ? practice based commissioning was resulting in increasing difficulties in cross health sector working in some sites ? the value of the public health model may not be captured in evaluation tools which focus on the individual patient experience. Recommendations Commissioners and providers 1. Disseminate new roles and innovations and articulate how the role or service fits and enhances existing provision. 2. Promote the role of the nurses in LTC management to patients and the wider community. 3. Actively engage with service users in shaping LTC services to meet patients’ needs. 4. Improve the support and supervision for nurses working within new roles. 5. Develop training and skills of nurses working in the community to enable them to take a more central role in LTC management. 6. Develop organisations that are enabling of innovation and actively seek funding for initiatives that provide an environment where nurses can reach their potential in improving LTC services. 7. Work towards data systems that are compatible between sectors and groups of professionals. Explore ways of enabling patients to access data and information systems for test results and latest information. 8. Promote horizontal as well as vertical integration of LTC services. Practitioners 1. Increase awareness of patient identified needs through active engagement with the service user. 2. Work to develop appropriate measures of nursing outcomes in LTC management including not only bureaucratic and physiological outcomes, but patient-identified outcomes. Implications of research findings 1. Investment should be made into changing patient perceptions about the traditional division of labour, the nurses’ role and skills, and the expertise available in primary care for CDM. 2. Development and evaluation of patient accessible websites where patients can access a range of information, their latest test results and ways of interpreting these. 3. Long-term funding of prospective evaluations to enable identification of CDM outcomes. 4. Mapping of patient experience and patient satisfaction so that the conceptual differences between these two related ideas can be demonstrated. 5. Development of appropriate measures of patient experience that can be used as part of the quality outcome measures. 6. Cost evaluation/effectiveness studies carried out over time that includes national quality outcome indicators and valid measures of patient experience. 7. The importance of whole system working needs to be identified in the planning of services. 8. Research into the role of the health visitor in chronic disease management within a public health model

Measurement of vertical velocity using clear-air Doppler radars

A new clear air Doppler radar was constructed, called the Flatland radar, in very flat terrain near Champaign-Urbana, Illinois. The radar wavelength is 6.02 m. The radar has been measuring vertical velocity every 153 s with a range resolution of 750 m almost continuously since March 2, 1987. The variance of vertical velocity at Flatland is usually quite small, comparable to the variance at radars located near rough terrain during periods of small background wind. The absence of orographic effects over very flat terrain suggests that clear air Doppler radars can be used to study vertical velocities due to other processes, including synoptic scale motions and propagating gravity waves. For example, near rough terrain the shape of frequency spectra changes drastically as the background wind increases. But at Flatland the shape at periods shorter than a few hours changes only slowly, consistent with the changes predicted by Doppler shifting of gravity wave spectra. Thus it appears that the short period fluctuations of vertical velocity at Flatland are alsmost entirely due to the propagating gravity waves

Shaped nozzles for cryogenic buffer gas beam sources

Cryogenic buffer gas beams are important sources of cold molecules. In this work we explore the use of a converging-diverging nozzle with a buffer-gas beam. We find that, under appropriate circumstances, the use of a nozzle can produce a beam with improved collimation, lower transverse temperatures, and higher fluxes per solid angle