245 research outputs found

    Climate Change, Woodpeckers, and Forests: Current Trends and Future Modeling Needs

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    The structure and composition of forest ecosystems are expected to shift with climate‐induced changes in precipitation, temperature, fire, carbon mitigation strategies, and biological disturbance. These factors are likely to have biodiversity implications. However, climate‐driven forest ecosystem models used to predict changes to forest structure and composition are not coupled to models used to predict changes to biodiversity. We proposed integrating woodpecker response (biodiversity indicator) with forest ecosystem models. Woodpeckers are a good indicator species of forest ecosystem dynamics, because they are ecologically constrained by landscape‐scale forest components, such as composition, structure, disturbance regimes, and management activities. In addition, they are correlated with forest avifauna community diversity. In this study, we explore integrating woodpecker and forest ecosystem climate models. We review climate–woodpecker models and compare the predicted responses to observed climate‐induced changes. We identify inconsistencies between observed and predicted responses, explore the modeling causes, and identify the models pertinent to integration that address the inconsistencies. We found that predictions in the short term are not in agreement with observed trends for 7 of 15 evaluated species. Because niche constraints associated with woodpeckers are a result of complex interactions between climate, vegetation, and disturbance, we hypothesize that the lack of adequate representation of these processes in the current broad‐scale climate–woodpecker models results in model–data mismatch. As a first step toward improvement, we suggest a conceptual model of climate–woodpecker–forest modeling for integration. The integration model provides climate‐driven forest ecosystem modeling with a measure of biodiversity while retaining the feedback between climate and vegetation in woodpecker climate change modeling

    Alginate and tunicate nanocellulose composite microbeads – Preparation, characterization and cell encapsulation

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    Alginate has been used for decades for cell encapsulation. Cellulose nanofibrils (CNF) from tunicates are desirable in biomedicine due to high molecular weight, purity, crystallinity, and sustainable production. We prepared microbeads of 400–600 ÎŒm of alginate and tunicate CNF. Greater size, dispersity and aspect ratio were observed in microbeads with higher fractions of CNF. CNF content in Ca-crosslinked alginate microbeads decreased stability upon saline exposure, whereas crosslinking with calcium (50 mM) and barium (1 mM) yielded stable microbeads. The Young's moduli of gel cylinders decreased when exchanging alginate with CNF, and slightly increased permeability to dextran was observed in microbeads containing CNF. Encapsulation of MC3T3 cells revealed high cell viability after encapsulation (83.6 ± 0.4%) in beads of alginate and CNF. NHDFs showed lower viability but optimizing mixing and production techniques of microbeads increased cell viability (from 66.2 ± 5.3% to 72.7 ± 7.5%).publishedVersio

    Current communication practices between obstetrics and gynecology residency applicants and program directors

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    Importance: In order to equitably improve the residency application process, it is essential to understand the problems we need to address. Objective: To determine how obstetrics and gynecology (OBGYN) applicants and faculty communicate applicants\u27 interest to residency programs, and how program directors report being influenced by these communications. Design, Setting, and Participants: This survey study was conducted with email surveys of OBGYN application stakeholders in 2022. Included participants were OBGYN applicants, clerkship directors, and residency program directors in medical education associations\u27 email listservs. Exposures: Surveys sent by the American Association of Medical Colleges, Association of Professors of Gynecology and Obstetrics, and Council on Resident Education in Obstetrics and Gynecology. Main Outcomes and Measures: Whether applicants themselves, or faculty on their behalf, communicated to residency programs, and the influence program directors reported placing on these communications for their decision-making. Descriptive statistics and χ2 tests were used to analyze differences. Results: A total 726 of 2781 applicants (26.1%) responded to the survey and were included in analysis (79 of 249 [31.7%] clerkship directors; 200 of 280 [71.4%] program directors). The self-reported racial and ethnic demographics of the 726 applicant respondents were 86 Asian (11.8%), 54 Black (7.4%), 41 Latinx (5.6%), 1 Native Hawaiian or Pacific Islander (0.1%), 369 White (52.2%), 45 with multiple racial identities (6.2%), and 91 (21.5%) preferring not to answer. The majority of applicants (590 [82.9%]) sent communications at some point in the application process. Applicants who identified as White (336 [88.7%]) or Asian (75 [87.2%]) were more likely than those who identified as Black (40 [74.1%]) or Latinx (33 [80.5%]) to reach out to programs (P = .02). There were also differences in type of medical school, with 377 of 427 MD applicants (88.3%), 109 of 125 DO applicants (87.2%), and 67 of 87 International Medical Graduate applicants (77.7%) reporting sending communications (P = .02). Approximately one-third (254 applicants [35.7%]) had faculty reach out to programs on their behalf. White (152 [40.1%]) and Asian (37 [43.0%]) applicants were more likely to have faculty reach out compared with Black (6 [11.1%]) and Latinx (12 [29.3%]) applicants (P = .01). Program directors reported that preinterview communications from faculty they knew (64 [32.2%]) and other program directors (25 [12.6%]) strongly influenced their decisions, and otherwise rarely reported that communications strongly influenced their decisions. Conclusions and Relevance: The current state of communications may increase inequities in residency application processes; differences between faculty communications for applicants from different racial and ethnic backgrounds are particularly concerning given that program directors are more likely to weigh communications from faculty in their decision-making. A centralized, equitable means for applicants to signal their interest to programs is urgently needed

    Reliability of translaryngeal airway resistance measurements during maximal exercise

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    Objective Exercise-induced laryngeal obstruction is an important cause of exertional dyspnoea. The diagnosis rests on visual judgement of relative changes of the laryngeal inlet during continuous laryngoscopy exercise (CLE) tests, but we lack objective measures that reflect functional consequences. We aimed to investigate repeatability and normal values of translaryngeal airway resistance measured at maximal intensity exercise. Methods 31 healthy nonsmokers without exercise-related breathing problems were recruited. Participants performed two CLE tests with verified positioning of two pressure sensors, one at the tip of the epiglottis (supraglottic) and one by the fifth tracheal ring (subglottic). Airway pressure and flow data were continuously collected breath-by-breath and used to calculate translaryngeal resistance at peak exercise. Laryngeal obstruction was assessed according to a standardised CLE score system. Results Data from 26 participants (16 females) with two successful tests and equal CLE scores on both test sessions were included in the translaryngeal resistance repeatability analyses. The coefficient of repeatability (CR) was 0.62 cmH2O·L−1·s−1, corresponding to a CR% of 21%. Mean±sd translaryngeal airway resistance (cmH2O·L−1·s−1) in participants with no laryngeal obstruction (n=15) was 2.88±0.50 in females and 2.18±0.50 in males. Higher CLE scores correlated with higher translaryngeal resistance in females (r=0.81, p<0.001). Conclusions This study establishes translaryngeal airway resistance obtained during exercise as a reliable parameter in respiratory medicine, opening the door for more informed treatment decisions and future research on the role of the larynx in health and disease.publishedVersio

    Chitosan-Modified Polyethyleneimine Nanoparticles for Enhancing the Carboxylation Reaction and Plants' CO2 Uptake

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    Increasing plants' photosynthetic efficienc y is a major challenge that must be addressed in order to cover the food demands of the growing population in the changing climate. Photosynthes i s is greatly limited at the initial carboxylation reaction, where CO2 is converted to the organic acid 3-PGA, catalyzed by the RuBisCO enzyme. RuBisCO has poor affinity for CO2, but also the CO2 concentration at the RuBisCO site is limited by the diffusion of atmospheric CO2 through the various leaf compartments to the reaction site. Beyond genetic engineer-ing, nanotechnology can offer a materials-based approach for enhancing photosynthesis, and yet, it has mostly been explored for the light-dependent reactions. In this work, we developed polyethyleneimine-based nanoparticl e s for enhancing the carbox-ylation reaction. We demonstrate that the nanoparticles can capture CO2 in the form of bicarbonate and increase the CO2 that reacts with the RuBisCO enzyme, enhancing the 3-PGA production in in vitro assays by 20%. The nanoparticles can be introduced to the plant via leaf infiltration and, because of the functionalization with chitosan oligomers, they do not induce any toxic effect to the plant. In the leaves, the nanoparticles localize in the apoplastic space but also spontaneously reach the chloroplasts where photosynthetic activity takes place. Their CO2 loading-dependent fluorescence verifies that, in vivo, they maintain their abi l i t y to capture CO2 and can be therefore reloaded with atmospheric CO2 while in planta. Our results contribute to the development of a nanomaterials-based CO2-concentrating mechanism in plants t h a t can potentially increase photosynthetic efficiency and overall plants' CO2 storage

    Putting the self in self-correction: findings from the loss-of-confidence project

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    Science is often perceived to be a self-correcting enterprise. In principle, the assessment of scientific claims is supposed to proceed in a cumulative fashion, with the reigning theories of the day progressively approximating truth more accurately over time. In practice, however, cumulative self-correction tends to proceed less efficiently than one might naively suppose. Far from evaluating new evidence dispassionately and infallibly, individual scientists often cling stubbornly to prior findings. Here we explore the dynamics of scientific self-correction at an individual rather than collective level. In 13 written statements, researchers from diverse branches of psychology share why and how they have lost confidence in one of their own published findings. We qualitatively characterize these disclosures and explore their implications. A cross-disciplinary survey suggests that such loss-of-confidence sentiments are surprisingly common among members of the broader scientific population yet rarely become part of the public record. We argue that removing barriers to self-correction at the individual level is imperative if the scientific community as a whole is to achieve the ideal of efficient self-correction

    Identification of response signatures for tankyrase inhibitor treatment in tumor cell lines

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    Small-molecule tankyrase 1 and tankyrase 2 (TNKS1/2) inhibitors are effective antitumor agents in selected tumor cell lines and mouse models. Here, we characterized the response signatures and the in-depth mechanisms for the antiproliferative effect of tankyrase inhibition (TNKSi). The TNKS1/2-specific inhibitor G007-LK was used to screen 537 human tumor cell lines and a panel of particularly TNKSi-sensitive tumor cell lines was identified. Transcriptome, proteome, and bioinformatic analyses revealed the overall TNKSi-induced response signatures in the selected panel. TNKSi-mediated inhibition of wingless-type mammary tumor virus integration site/b-catenin, yes-associated protein 1 (YAP), and phosphatidylinositol-4,5-bisphosphate 3-kinase/AKT signaling was validated and correlated with lost expression of the key oncogene MYC and impaired cell growth. Moreover, we show that TNKSi induces accumulation of TNKS1/2-containing b-catenin degradasomes functioning as core complexes interacting with YAP and angiomotin proteins during attenuation of YAP signaling. These findings provide a contextual and mechanistic framework for using TNKSi in anticancer treatment that warrants further comprehensive preclinical and clinical evaluations.publishedVersio

    Population-level effects of human papillomavirus vaccination programs on infections with nonvaccine genotypes

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    We analyzed human papillomavirus (HPV) prevalences during prevaccination and postvaccination periods to consider possible changes in nonvaccine HPV genotypes after introduction of vaccines that confer protection against 2 high-risk types, HPV16 and HPV18. Our meta-analysis included 9 studies with data for 13,886 girls and women ≀19 years of age and 23,340 women 20–24 years of age. We found evidence of cross-protection for HPV31 among the younger age group after vaccine introduction but little evidence for reductions of HPV33 and HPV45. For the group this same age group, we also found slight increases in 2 nonvaccine high-risk HPV types (HPV39 and HPV52) and in 2 possible high-risk types (HPV53 and HPV73). However, results between age groups and vaccines used were inconsistent, and the increases had possible alternative explanations; consequently, these data provided no clear evidence for type replacement. Continued monitoring of these HPV genotypes is important
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