Species traits and observer behaviors that bias data assimilation and how to accommodate them.

Datasets that monitor biodiversity capture information differently depending on their design, which influences observer behavior and can lead to biases across observations and species. Combining different datasets can improve our ability to identify and understand threats to biodiversity, but this requires an understanding of the observation bias in each. Two datasets widely used to monitor bird populations exemplify these general concerns: eBird is a citizen science project with high spatiotemporal resolution but variation in distribution, effort, and observers, whereas the Breeding Bird Survey (BBS) is a structured survey of specific locations over time. Analyses using these two datasets can identify contradictory population trends. To understand these discrepancies and facilitate data fusion, we quantify species-level reporting differences across eBird and the BBS in three regions across the United States by jointly modeling bird abundances using data from both datasets. First, we fit a joint Species Distribution Model that accounts for environmental conditions and effort to identify reporting differences across the datasets. We then examine how these differences in reporting are related to species traits. Finally, we analyze species reported to one dataset but not the other and determine whether traits differ between reported and unreported species. We find that most species are reported more in the BBS than eBird. Specifically, we find that compared to eBird, BBS observers tend to report higher counts of common species and species that are usually detected by sound. We also find that species associated with water are reported less in the BBS. Species typically identified by sound are reported more at sunrise than later in the morning. Our results quantify reporting differences in eBird and the BBS to enhance our understanding of how each captures information and how they should be used. The reporting rates we identify can also be incorporated into observation models through detectability or effort to improve analyses across species and datasets. The method demonstrated here can be used to compare reporting rates across any two or more datasets to examine biases.

North American tree migration paced by climate in the West, lagging in the East.

Tree fecundity and recruitment have not yet been quantified at scales needed to anticipate biogeographic shifts in response to climate change. By separating their responses, this study shows coherence across species and communities, offering the strongest support to date that migration is in progress with regional limitations on rates. The southeastern continent emerges as a fecundity hotspot, but it is situated south of population centers where high seed production could contribute to poleward population spread. By contrast, seedling success is highest in the West and North, serving to partially offset limited seed production near poleward frontiers. The evidence of fecundity and recruitment control on tree migration can inform conservation planning for the expected long-term disequilibrium between climate and forest distribution.

Is there tree senescence? The fecundity evidence.

Despite its importance for forest regeneration, food webs, and human economies, changes in tree fecundity with tree size and age remain largely unknown. The allometric increase with tree diameter assumed in ecological models would substantially overestimate seed contributions from large trees if fecundity eventually declines with size. Current estimates are dominated by overrepresentation of small trees in regression models. We combined global fecundity data, including a substantial representation of large trees. We compared size-fecundity relationships against traditional allometric scaling with diameter and two models based on crown architecture. All allometric models fail to describe the declining rate of increase in fecundity with diameter found for 80% of 597 species in our analysis. The strong evidence of declining fecundity, beyond what can be explained by crown architectural change, is consistent with physiological decline. A downward revision of projected fecundity of large trees can improve the next generation of forest dynamic models.

Flower orientation influences floral temperature, pollinator visits and plant fitness.

Effective insect pollination requires appropriate responses to internal and external environmental cues in both the plant and the pollinator. Helianthus annuus, a highly outcrossing species, is marked for its uniform eastward orientation of mature pseudanthia, or capitula. Here we investigate how this orientation affects floral microclimate and the consequent effects on plant and pollinator interactions and reproductive fitness. We artificially manipulated sunflower capitulum orientation and temperature in both field and controlled conditions and assessed flower physiology, pollinator visits, seed traits and siring success. East-facing capitula were found to have earlier style elongation, pollen presentation and pollinator visits compared with capitula manipulated to face west. East-facing capitula also sired more offspring than west-facing capitula and under some conditions produced heavier and better-filled seeds. Local ambient temperature change on the capitulum was found to be a key factor regulating the timing of style elongation, pollen emergence and pollinator visits. These results indicate that eastward capitulum orientation helps to control daily rhythms in floral temperature, with direct consequences on the timing of style elongation and pollen emergence, pollinator visitation, and plant fitness.

Continent-wide tree fecundity driven by indirect climate effects.

Indirect climate effects on tree fecundity that come through variation in size and growth (climate-condition interactions) are not currently part of models used to predict future forests. Trends in species abundances predicted from meta-analyses and species distribution models will be misleading if they depend on the conditions of individuals. Here we find from a synthesis of tree species in North America that climate-condition interactions dominate responses through two pathways, i) effects of growth that depend on climate, and ii) effects of climate that depend on tree size. Because tree fecundity first increases and then declines with size, climate change that stimulates growth promotes a shift of small trees to more fecund sizes, but the opposite can be true for large sizes. Change the depresses growth also affects fecundity. We find a biogeographic divide, with these interactions reducing fecundity in the West and increasing it in the East. Continental-scale responses of these forests are thus driven largely by indirect effects, recommending management for climate change that considers multiple demographic rates.

Application of remote sensing technology to estimate productivity and assess phylogenetic heritability.

PREMISE: Measuring plant productivity is critical to understanding complex community interactions. Many traditional methods for estimating productivity, such as direct measurements of biomass and cover, are resource intensive, and remote sensing techniques are emerging as viable alternatives. METHODS: We explore drone-based remote sensing tools to estimate productivity in a tallgrass prairie restoration experiment and evaluate their ability to predict direct measures of productivity. We apply these various productivity measures to trace the evolution of plant productivity and the traits underlying it. RESULTS: The correlation between remote sensing data and direct measurements of productivity varies depending on vegetation diversity, but the volume of vegetation estimated from drone-based photogrammetry is among the best predictors of biomass and cover regardless of community composition. The commonly used normalized difference vegetation index (NDVI) is a less accurate predictor of biomass and cover than other equally accessible vegetation indices. We found that the traits most strongly correlated with productivity have lower phylogenetic signal, reflecting the fact that high productivity is convergent across the phylogeny of prairie species. This history of trait convergence connects phylogenetic diversity to plant community assembly and succession. DISCUSSION: Our study demonstrates (1) the importance of considering phylogenetic diversity when setting management goals in a threatened North American grassland ecosystem and (2) the utility of remote sensing as a complement to ground measurements of grassland productivity for both applied and fundamental questions.

The emergent interactions that govern biodiversity change.

Observational studies have not yet shown that environmental variables can explain pervasive nonlinear patterns of species abundance, because those patterns could result from (indirect) interactions with other species (e.g., competition), and models only estimate direct responses. The experiments that could extract these indirect effects at regional to continental scales are not feasible. Here, a biophysical approach quantifies environment- species interactions (ESI) that govern community change from field data. Just as species interactions depend on population abundances, so too do the effects of environment, as when drought is amplified by competition. By embedding dynamic ESI within framework that admits data gathered on different scales, we quantify responses that are induced indirectly through other species, including probabilistic uncertainty in parameters, model specification, and data. Simulation demonstrates that ESI are needed for accurate interpretation. Analysis demonstrates how nonlinear responses arise even when their direct responses to environment are linear. Applications to experimental lakes and the Breeding Bird Survey (BBS) yield contrasting estimates of ESI. In closed lakes, interactions involving phytoplankton and their zooplankton grazers play a large role. By contrast, ESI are weak in BBS, as expected where year-to-year movement degrades the link between local population growth and species interactions. In both cases, nonlinear responses to environmental gradients are induced by interactions between species. Stability analysis indicates stability in the closed-system lakes and instability in BBS. The probabilistic framework has direct application to conservation planning that must weigh risk assessments for entire habitats and communities against competing interests.

Exploring the potential of gametic reconstruction of parental genotypes by F1 hybrids as a bridge for rapid introgression.

Interspecific hybridization and genetic introgression are commonly observed in natural populations of many species, especially trees. Among oaks, gene flow between closely related species has been well documented. And yet, hybridization does not lead to a "melting pot", i.e., the homogenization of phenotypic traits. Here, we explore how the combination of several common reproductive and genomic traits could create an avenue for interspecific gene flow that partially explains this apparent paradox. During meiosis, F1 hybrids will produce approximately (½)n "reconstructed" parental gametes, where n equals the number of chromosomes. Crossing over would introduce a small amount of introgressive material. The resulting parental-type gametophytes would probably possess a similar fertilization advantage as conspecific pollen. The resulting "backcross" would actually be the genetic equivalent of a conspecific out-cross, with a small amount of heterospecific DNA captured through crossing over. Even with detailed genomic analysis, the resulting offspring would not appear to be a backcross. This avenue for rapid introgression between species through the F1 hybrid will be viable for organisms that meet certain conditions: low base chromosome number, conserved genomic structure and size, production of billions of gametes/gametophytes during each reproductive event, and conspecific fertilization advantage.

A new biomaterial of nanofibers with the microalga Spirulina as scaffolds to cultivate with stem cells for use in tissue engineering.

The association of stem cells (SCs) with biomaterials promises to be the protagonist for future regenerative medicine in the treatment of tissue and organ lesions. Stem cells were cultivated in scaffolds constructed by the electrospinning technique, using poly-D,L-lactic acid (PDLLA) associated or not with Spirulina biomass (PDLLA/Sp), which has bioactive components of interest for tissue engineering (TE). Physicochemical analyses were performed, such as morphology, fiber diameter, degradability, residual solvent, roughness, contact angle with water, among others. SCs adhesion, proliferation and scaffold cytotoxicity were also evaluated. Nanofibers without beads and with characteristics similar to the natural extracellular matrix (ECM) in terms of mechanical and topographical properties were obtained. In biological tests it was found that SCs adhered more and had greater viability in the PDLLA/Sp molds, when compared with the PDLLA scaffolds. The scaffolds were shown to be atoxic for the SCs. It can be concluded that the scaffolds developed in this work have the characteristics to be a new biomaterial suitable for use in TE.

Early-onset scleral and corneal ectasias following low-dose mitomycin-C-augmented trabeculectomy in a uveitic glaucoma patient.

A case of early-onset sclerolimbal ectasia following low-dose topical mitomycin C application during uveitic glaucoma surgery is reported. Intraoperative and postoperative clinical courses were consistent with sclerolimbal ectasia. Adjunctive utilization of intraoperative low-dose 0.02% mitomycin C for the management of chronic uveitic glaucoma patients who are under concomitant systemic immunosuppressive regimen may enhance the risk of subacute postoperative sclerolimbal ectasia. Mitomycin C concentrations < 0.02%, decreased scleral exposure time, and a strict informed consent policy are strongly recommended in this subset of uveitic patients.

Impact of chronic transfusion on incidence of pain and acute chest syndrome during the Stroke Prevention Trial (STOP) in sickle-cell anemia.

OBJECTIVE: The Stroke Prevention Trial (STOP) demonstrated that chronic transfusion is highly effective in reducing the risk of stroke in children with sickle-cell disease and an abnormal transcranial Doppler ultrasonography examination result. Our objective was to determine whether chronic transfusion therapy reduces the incidence of pain and acute chest syndrome. METHODS: During STOP, 130 children with sickle-cell anemia or sickle beta(0)-thalassemia and abnormal transcranial Doppler ultrasonography examination result were randomly assigned to chronic transfusion (n = 63) or observation (n = 67). In addition to monitoring for stroke, nonneurologic sickle-cell complications were identified and recorded. RESULTS: Mean age at STOP study entry was 8.3 +/- 3.3 years, and mean follow-up was 19.6 +/- 6.5 months. Hospitalization rates (based on intent-to-treat analysis) for acute chest syndrome were 4.8 and 15.3 per 100 patient-years (P =.0027) and for pain were 16.2 and 27.6 per 100 patient-years (P =.13) in the chronic transfusion and observed groups, respectively. If analyzed according to treatment actually received, the difference in pain rate becomes significant (9.7 vs 27.1 events per 100 patient-years, P =.014), and transfusion remains protective from acute chest syndrome (2.2 vs 15.7 events per 100 patient-years, P =.0001). CONCLUSIONS: Compliance with aggressive chronic transfusion reduces the frequency of acute chest syndrome and pain episodes.

Factorial validity of the Childhood Trauma Questionnaire in men and women.

In an effort to confirm the factorial validity of the Childhood Trauma Questionnaire (CTQ) across sex, the items from the CTQ for 916 university students were subjected to confirmatory factor analysis. Results indicated that the factor structure for the CTQ was significantly different for men and women. For women, the items from the Physical Abuse subscale did not create a stable factor and thus appear not to be conceptually valid. Conversely, for men, the five-factor model provided a relatively good fit to the data. This investigation provides important information regarding sex differences in the factorial validity of the CTQ. Implications and future research directions are discussed.

The childhood trauma questionnaire in a community sample: psychometric properties and normative data.

Interpretation of research on the prevalence and sequelae of childhood trauma has been hindered by the use of assessment instruments with unknown psychometric properties. Thus, we examined the psychometric properties of a new childhood trauma measure, the Childhood Trauma Questionnaire (CTQ). The CTQ has demonstrated strong psychometric properties in clinical samples; limited information exists on its psychometric properties in community samples. Therefore, we explored the factor structure and reliability of the CTQ in a community sample and calculated normative data. Consistent with previous literature, a 5-factor model best described the CTQ, with a hierarchical model also providing excellent fit. Additionally, the CTQ demonstrated acceptable internal consistency. Overall, our findings suggest that the CTQ is appropriate for use in a community sample.

Anxiety disorders in the elderly.

Although the epidemiology, neurobiology, and treatment of anxiety disorders have received considerable attention in the child and adult literature, they have not received the same consideration in the geriatric population. This disparity is remarkable given the prevalence and associated costs of these disorders that can persist into late life. Further, although a considerable amount is known about these disorders in younger age groups, it is unclear whether the phenomenology of anxiety evolves over the course of the aging process. Thus, conclusions drawn based on younger populations of anxious adults may not hold true for older cohorts. This article reviews issues of epidemiology, phenomenology, neurobiology, and medical comorbidity, as well as pharmacologic and psychotherapeutic treatments in older adults.

Systemic toxicity of topical and periocular corticosteroid therapy in an 11-year-old male with posterior uveitis.

PURPOSE: To report a case of systemic corticosteroid toxicity resulting from topical and periocular therapy. METHODS: Treatment and follow-up of an 11-year-old male with uveitis are illustrated. Initial presentation of the patient was bilateral iridocyclitis, for which he was treated with prednisolone acetate 1% every 2 hours for 6 months. Subsequently, posterior uveitis developed, necessitating posterior subtenon injections. RESULTS: After initial topical corticosteroid therapy, the patient developed a cushingoid habitus accompanied by increased lanugo hair, acanthosis nigricans, posterior subcapsular lens opacities, and increased intraocular pressure. Cushingoid stigmata worsened after administration of posterior subtenon injection of corticosteroids. The patient's truncal obesity worsened, and his linear growth stopped. CONCLUSIONS: Systemic toxic effects may develop as a result of topical and local use of ophthalmic corticosteroid preparations in susceptible patients.

Novel multiagent chemotherapy for bone marrow relapse of pediatric acute lymphoblastic leukemia.

BACKGROUND: Despite improvements in the treatment of pediatric acute lymphoblastic leukemia, approximately one in five patients will develop recurrent disease. The majority of these patients do not survive. This limited institution study sought to improve event-free survival (EFS) by intensification of chemotherapy. PROCEDURE: Twenty-one patients with either an isolated marrow (n = 16) or a combined marrow and central nervous system relapse (n = 5) received treatment according to Children's Hospital of Philadelphia protocol CHP-540. Six patients had an initial remission of <36 months, and five patients had relapsed within 1 year of completion of phase III therapy. Induction and reinduction therapy consisted of idarubicin, vincristine, dexamethasone, asparaginase, and triple intrathecal chemotherapy. Consolidation and reconsolidation therapy employed high-dose cytarabine, etoposide, and asparaginase given in a sequential manner. Maintenance therapy included courses of high- or low-dose cytarabine followed by sequential etoposide and asparaginase pulse, moderate-dose methotrexate with delayed leukovorin rescue, and vincristine/dexamethasone pulses. Therapy continued for 2 years from the start of interim maintenance in the 16 patients who did not receive a bone marrow transplant (BMT). Two patients underwent an HLA-identical sibling BMT specified by protocol. Four received a nonprotocol-prescribed alternative donor BMT. RESULTS: The complete remission induction rate was 95%. With a median follow-up from date of relapse of 49 months in survivors, the actuarial EFS based on intent to treat is 75%. There were three toxic deaths in patients in CR and two deaths from relapse. CONCLUSIONS: This regimen is toxic but effective and deserves study in a larger setting.

The self-reporting of psychiatric medications in patients scheduled for elective surgery.

STUDY OBJECTIVE: To determine by survey the percentage of patients, over the age of 21 years, reporting for elective surgery who also are taking psychotropic medications. DESIGN: Institution-approved, anonymous survey. SETTING: Teaching hospital. PATIENTS: 169 patients who were scheduled for elective surgery. INTERVENTIONS: After completion of the preoperative evaluation by members of the anesthesia care team, all patients were given an institution-approved survey of medications they were taking in addition to their nonpsychiatric medications. The survey listed 33 drugs known to affect central nervous system neurotransmitters, and included the most commonly prescribed antidepressants, antipsychotics, benzodiazapines, and lithium. Over-the-counter drugs known to affect mood, such as melatonin, also were included in the survey. Patients were not asked the indications for the medications, and no psychiatric questions were asked of the patients. MEASUREMENTS AND MAIN RESULTS: 300 surveys were distributed, and 169 patients completed the survey for a response rate of 53%. Forty-three percent of all patients who completed the survey admitted to taking one or more of the psychotropic medications. Of these patients, 35% were taking antidepressants, 34% were taking benzodiazapines, 19% were taking combination therapies, and 11% took antipsychotics, lithium, or over-the-counter drugs such as melatonin. CONCLUSION: The number of patients taking psychotropic medications and who present for elective surgery is high. The anesthetic implications of this drug usage are essentially unknown. Additional study of these medications and their impact on anesthetic care is warranted.

Stroke prevention trial in sickle cell anemia.

Stroke occurs in 7-8% of children with Sickle Cell Disease (Hb SS) and is a major cause of morbidity. Rates of recurrence have been reduced from 46-90% to less than 10% through chronic blood transfusions. Prevention of first stroke, however, would be preferable because even one stroke can cause irreversible brain injury. Transcranial Doppler (TCD) ultrasound can detect arterial blood flow rates associated with subsequent stroke risk. By combining TCD screening and a potentially effective treatment, first stroke may be prevented. The Stroke Prevention Trial in Sickle Cell Anemia (STOP) is the first stroke prevention trial in Hb SS and the first randomized, controlled use of transfusion in Hb SS. This multi-center trial is designed to test whether reducing sickle hemoglobin to 30% or less with periodic blood transfusions will reduce first-time stroke by at least 70% compared to standard care. Primary endpoints will be clinically evident symptoms of cerebral infarction with consistent findings on Magnetic Resonance Imaging and Angiography (MRI/MRA) or symptomatic intracranial hemorrhage. Secondary endpoints will be asymptomatic brain lesions detected by MRI in brain areas not involved in primary endpoints. The design calls for a 6-month start-up interval, 18 months of TCD screening and randomization, and observation for stroke from entry through month 54. Key features of the trial are standardized TCD and MRI/MRA protocols interpreted blindly, and blinded adjudication of endpoints. The sample size (60 per treatment group) is based on prospective data relating TCD velocity to risk of stroke. A time-averaged mean velocity of > or = 200 cm/sec is associated with a 46% risk of cerebral infarction over 39 months. The sample size is sufficient to detect 70% reduction in the primary endpoint at 90% power. This trial will determine if transfusion is effective in the primary prevention of stroke. Secondary aims may further the understanding of the effects of transfusion on the brain and guide future research into cerebrovascular disease in Hb SS.

Factor V Leiden is not responsible for stroke in patients with sickling disorders and is uncommon in African Americans with sickle cell disease.

Cerebrovascular accidents in patients with sickle cell anemia are among the most devastating complications of the disease. It has recently been demonstrated that some patients have a hypercoagulable state on the basis of the presence of an abnormal factor V molecule, factor V Leiden. We undertook this study to evaluate the presence of factor V Leiden in sickle cell patients with stroke. Eighty-two patients with either Hgb SS, Hgb SC, or Hgb S(beta+)-thalassemia comprised the study population. Of the 82 patients in the study, 19 of them had a history of stroke. In our study population, none of the stroke patients possessed the factor V Leiden mutation. One of the non-stroke patients was a heterozygote for the mutation (P = 1.00). The overall frequency of the factor V Leiden allele in our population is 0.6%. The estimated prevalence for this mutation is reportedly between 3 and 7% in Caucasian populations. We conclude that the gene frequency for factor V Leiden is less common in Africa Americans with sickle cell disease. Furthermore, factor V Leiden does not appear to be responsible for the development of stroke in sickle cell patients.