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Biodiversity faces unprecedented threats from rapid global change1. Signals of biodiversity change come from time-series abundance datasets for thousands of species over large geographic and temporal scales. Analyses of these biodiversity datasets have pointed to varied trends in abundance, including increases and decreases. However, these analyses have not fully accounted for spatial, temporal and phylogenetic structures in the data. Here, using a new statistical framework, we show across ten high-profile biodiversity datasets2-11 that increases and decreases under existing approaches vanish once spatial, temporal and phylogenetic structures are accounted for. This is a consequence of existing approaches severely underestimating trend uncertainty and sometimes misestimating the trend direction. Under our revised average abundance trends that appropriately recognize uncertainty, we failed to observe a single increasing or decreasing trend at 95% credible intervals in our ten datasets. This emphasizes how little is known about biodiversity change across vast spatial and taxonomic scales. Despite this uncertainty at vast scales, we reveal improved local-scale prediction accuracy by accounting for spatial, temporal and phylogenetic structures. Improved prediction offers hope of estimating biodiversity change at policy-relevant scales, guiding adaptive conservation responses.

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A long-standing question in ecology is whether phenotypic plasticity, rather than selection per se, is responsible for phenotypic variation among populations. Plasticity can increase or decrease variation, but most previous studies have been limited to single populations, single traits and a small number of environments assessed using univariate reaction norms. Here, examining two genetically distinct populations of Daphnia pulex with different predation histories, we quantified predator-induced plasticity among 11 traits along a fine-scale gradient of predation risk by a predator (Chaoborus) common to both populations. We test the hypothesis that plasticity can be responsible for convergence in phenotypes among different populations by experimentally characterizing multivariate reaction norms with phenotypic trajectory analysis (PTA). Univariate analyses showed that all genotypes increased age and size at maturity, and invested in defensive spikes (neckteeth), but failed to quantitatively describe whole-organism response. In contrast, PTA quantified and qualified the phenotypic strategy the organism mobilized against the selection pressure. We demonstrate, at the whole-organism level, that the two populations occupy different areas of phenotypic space in the absence of predation but converge in phenotypic space as predation threat increases.

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Phenotypic plasticity is one major source of variation in natural populations. Inducible defences, which can be considered threshold traits, are a form of plasticity that generates ecological and evolutionary consequences. A simple cost-benefit model underpins the maintenance and evolution of these threshold, inducible traits. In this model, a rank-order switch in expected fitness, defined by costs and benefits of induction between defended and undefended morphs, predicts the risk level at which individuals should induce defences. Here, taking predator-induced morphological defences in Daphnia pulex as a threshold trait, we provide the first comprehensive investigation into the costs and benefits of a threshold trait, and how they combine to reflect fitness and predict the switchpoint at which induction should occur. We develop reaction norms that show genetic variation in switchpoints. Further experiments show that induction can confer a survival benefit and a cost in terms of lifetime reproductive success. Together, these two traits combine to estimate expected fitness and can predict the switchpoint between an undefended and a defended strategy. The predictions match the reaction norm data for clones that experience these costs and benefits, and correspond well to independent field data on induction. However, predictions do not, and cannot, match for clones that do not gain a benefit from induction. This study confirms that a simple theory, based on life history costs and benefits, is a sufficient framework for understanding the ecology and evolution of inducible, threshold traits.

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Many natural enemies do not immediately kill their host, and the lag this creates between attack and host death results in mixed populations of uninfected and infected hosts. Both competition and parasitism are known to be major structuring forces in ecological communities; however, surprisingly little is known about how the competitive nature of infected hosts could affect the survival and dynamics of remaining uninfected host populations. Using a laboratory system comprising the Indian meal moth, Plodia interpunctella, and a solitary koinobiont parasitoid, Venturia canescens, we address this question by conducting replicated competition experiments between the unparasitized and parasitized classes of host larvae. For varying proportions of parasitized host larvae and competitor densities, we consider the effects of competition within (intraclass) and between (interclass) unparasitized and parasitized larvae on the survival, development time, and size of adult moths and parasitoid wasps. The greatest effects were on survival: increased competitor densities reduced survival of both parasitized and unparasitized larvae. However, unparasitized larvae survival, but not parasitized larvae survival, was reduced by increasing interclass competition. To our knowledge, this is the first experimental demonstration of the competitive superiority of parasitized over unparasitized hosts for limiting resources. We discuss possible mechanisms for this phenomenon, why it may have evolved, and its possible influence on the stability of host-parasite dynamics.

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The way that mothers provision their offspring can have important consequences for their offspring's performance throughout life. Models suggest that maternally induced variation in life histories may have large population dynamical effects, even perhaps driving cycles such as those seen in forest Lepidoptera. The evidence for large maternal influences on population dynamics is unconvincing, principally because of the difficulty of conducting experiments at both the individual and population level. In the soil mite, Sancassania berlesei, we show that there is a trade-off between a female's fecundity and the per-egg provisioning of protein. The mother's position on this trade-off depends on her current food availability and her age. Populations initiated with 250 eggs of different mean sizes showed significant differences in the population dynamics, converging only after three generations. Differences in the growth, maturation and fecundity of the initial cohort caused differences in the competitive environment for the next generation, which, in turn, created differences in their growth and reproduction. Maternal effects in one generation can therefore lead to population dynamical consequences over many generations. Where animals live in environments that are temporally variable, we conjecture that maternal effects could result in long-term dynamical effects.

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This study aims to evaluate the efficacy of the Histofreezer (a mobile aerosol cryotherapy device) treatment for women with cervical contact bleeding. Ten healthy women aged 22-50 years referred to our outpatient colposcopy clinic for recurrent postcoital or contact bleeding, and who suffered from mild to wide ectropion with bleeding on contact were studied. All women had a normal pelvic examination and ultrasound and a normal colposcopy and PAP smear. They were treated with the Histofreezer, which freezes the tissue to a temperature of -55 degrees C. A picture of the cervix was taken by a cervical camera before, after the procedure and during follow-up visits 4 and 8 weeks afterwards. There was a complete resolution of bleeding ectropion with a good healing of squamous metaplasia in seven patients. Two women showed partial improvement. Based on this initial study, this short and simple ambulatory treatment shows good results, both subjectively and on follow-up colposcopy.

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Case workers involved in permanency planning for children whose mothers are incarcerated must assess the family's strengths, the mother's capacity to assume parental responsibilities, and the integrity of the parent-child relationship; and address concerns regarding the short- and long-term effects of the children's socioemotional dislocation and the merits of their retaining a relationship with their mothers. At the same time, correctional policies and practices delineate the nature and extent of contacts with the mother and the mother's access to rehabilitative programs. Agency guidelines, practice tools, and advocacy initiatives must be developed to help practitioners meet these challenges. An initial review of the Adoption and Safe Families Act suggests the need for close monitoring of the impact of its mandates to shorten the time for moving children toward permanency and its weakening of the expectation for "reasonable efforts" to be made to reunify families.

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Predators of herbivorous animals can affect plant populations by altering herbivore density, behavior, or both. To test whether the indirect effect of predators on plants arises from density or behavioral responses in a herbivore population, we experimentally examined the dynamics of terrestrial food chains comprised of old field plants, leaf-chewing grasshoppers, and spider predators in Northeast Connecticut. To separate the effects of predators on herbivore density from the effects on herbivore behavior, we created two classes of spiders: (i) risk spiders that had their feeding mouth parts glued to render them incapable of killing prey and (ii) predator spiders that remained unmanipulated. We found that the effect of predators on plants resulted from predator-induced changes in herbivore behavior (shifts in activity time and diet selection) rather than from predator-induced changes in grasshopper density. Neither predator nor risk spiders had a significant effect on grasshopper density relative to a control. This demonstrates that the behavioral response of prey to predators can have a strong impact on the dynamics of terrestrial food chains. The results make a compelling case to examine behavioral as well as density effects in theoretical and empirical research on food chain dynamics.

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The term "alternate level of care" (ALC) refers to the status of hospitalized patients who are no longer acutely ill but cannot be discharged because posthospital plans are not yet in place. ALC is a major problem for patients, families, and hospitals. This article describes the experiences of an urban teaching hospital with ALC and the development of a computerized database to better manage the ALC population. Among the findings were that age, waiting for a nursing home placement, family-related discharge problems, and pending Medicaid eligibility all significantly contributed to length of stay beyond the acute phase of the illness. Using these data, the hospital developed an innovative program in which the preparation of Medicaid applications was transferred from the Department of Finance to the Department of Social Work Services.

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OBJECTIVE: To identify the patients' experience of cardiac catheterization. DESIGN: Descriptive, qualitative, phenomenologic. SETTING: Large southeastern teaching hospital with an active cardiac catheterization laboratory and research center. PATIENTS: Ten men, between 44 and 73 years of age, who had undergone their first cardiac catheterization. RESULTS: The participants described feelings of loss of control of physical and personal self; an increased fear of the unknown during the test and especially of outcomes that might affect their future; a focus on time and its relationship to complication; a need not to be alone and not to be isolated after the test; and an awareness of spiritual belief in the good of others, trusting in their competencies. CONCLUSIONS: This study suggests the need for more attention to the psychologic aspects of the test, especially to the outcomes, negative as well as positive, and how they may affect the patient.

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In this article the author, through a process of contemplation, sought to put into words the inner feelings and experiences of caring depicted in six works of art. The questions the author explored were, Is the language of caring present in all environments? Are there similarities or dissimilarities? Evidence of caring was found in all the paintings, some of which were painted during the Holocaust. The paintings and the journaling process are described.

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This article describes a study of incarcerated mothers in New York State prisons who had children in foster care. Prerequisite conditions for permanency planning activities between mothers and caseworkers are examined, with a focus on the incidence of correspondence, telephone contact, and notification of court hearings. Although most of the mothers questioned reported having telephone contact or correspondence with caseworkers, a sizable number reported having neither, and less than half were familiar with the procedures that would enable them to appear for court hearings. Failure to engage in such activities jeopardizes the parental status of the incarcerated mother. Recommendations are made for changes in policies and practice that facilitate increased correspondence and telephone contact as well as notification of and attendance at court hearings.

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1. The older patient has unique needs and vulnerabilities that pose a challenge to nursing. 2. Excess nosocomial infections, incontinence, confusion, activity limitations, skin breakdown, and increased posthospitalization mortality are potential negative outcomes of older adult hospitalization. 3. There is some evidence of age bias in clinical decisions made regarding the older patient. 4. Additional preparation in gerontological nursing, increased sensitization to the needs of older patients, more specialized units, and greater emphasis on basic needs in the acute care setting are necessary to enhance quality nursing care for the frail older patient.

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The Community Residence Program described is sponsored by an urban teaching hospital and supported by state funds. The program uses scatter-site apartments in the community to house 120 patients in a therapeutic milieu as part of their comprehensive aftercare treatment. The program stresses teaching the skills of daily living to patients with chronic, psychiatric illnesses. The conceptual model used is based on challenges and tasks appropriate for this population. Preliminary evaluation findings suggest that the program is successful in teaching patients social skills, helping them adhere to medical regimens, perform household chores and observe fire safety regulations.

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While the term "drug-nutrient interactions" tends to conjure up a concept of an adverse combination, such as anticonvulsants impairing folate metabolism or alcohol blocking active thiamine absorption, there are situations in which a drug and nutrient can act in a complementary manner, to correct a metabolic defect. This case history illustrates such a positive interaction of glucocorticoids and L-carnitine supplements improving muscle function in a patient with myopathic carnitine deficiency.

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