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Forecasting plant responses under global change is a critical but challenging endeavour. Despite seemingly idiosyncratic responses of species to global change, greater generalisation of 'winners' and 'losers' may emerge from considering how species functional traits influence responses and how these responses scale to the community level. Here, we synthesised six long-term global change experiments combined with locally measured functional traits. We quantified the change in abundance and probability of establishment through time for 70 alpine plant species and then assessed if leaf and stature traits were predictive of species and community responses across nitrogen addition, snow addition and warming treatments. Overall, we found that plants with more resource-acquisitive trait strategies increased in abundance but each global change factor was related to different functional strategies. Nitrogen addition favoured species with lower leaf nitrogen, snow addition favoured species with cheaply constructed leaves and warming showed few consistent trends. Community-weighted mean changes in trait values in response to nitrogen addition, snow addition and warming were often different from species-specific trait effects on abundance and establishment, reflecting in part the responses and traits of dominant species. Together, these results highlight that the effects of traits can differ by scale and response of interest.

Accompanying the climate crisis is the more enigmatic biodiversity crisis. Rapid reorganization of biodiversity due to global environmental change has defied prediction and tested the basic tenets of conservation and restoration. Conceptual and practical innovation is needed to support decision making in the face of these unprecedented shifts. Critical questions include: How can we generalize biodiversity change at the community level? When are systems able to reorganize and maintain integrity, and when does abiotic change result in collapse or restructuring? How does this understanding provide a template to guide when and how to intervene in conservation and restoration? To this end, we frame changes in community organization as the modulation of external abiotic drivers on the internal topology of species interactions, using plant-plant interactions in terrestrial communities as a starting point. We then explore how this framing can help translate available data on species abundance and trait distributions to corresponding decisions in management. Given the expectation that community response and reorganization are highly complex, the external-driver internal-topology (EDIT) framework offers a way to capture general patterns of biodiversity that can help guide resilience and adaptation in changing environments.

Neurological disorders are often debilitating conditions with no cure. The majority of current therapies are palliative rather than disease-modifying; therefore, new strategies for treating neurological disorders are greatly needed. mRNA-based therapeutics have great potential for treating such neurological disorders; however, challenges with delivery have limited their clinical potential. Lipid nanoparticles (LNPs) are a promising delivery vector for the brain, given their safer toxicity profile and higher efficacy. Despite this, very little is known about LNP-mediated delivery of mRNA into the brain. Here, we employ MC3-based LNPs and successfully deliver Cre mRNA and Cas9 mRNA/Ai9 sgRNA to the adult Ai9 mouse brain; greater than half of the entire striatum and hippocampus was found to be penetrated along the rostro-caudal axis by direct intracerebral injections of MC3 LNP mRNAs. MC3 LNP Cre mRNA successfully transfected cells in the striatum (∼52% efficiency) and hippocampus (∼49% efficiency). In addition, we demonstrate that MC3 LNP Cas9 mRNA/Ai9 sgRNA edited cells in the striatum (∼7% efficiency) and hippocampus (∼3% efficiency). Further analysis demonstrates that MC3 LNPs mediate mRNA delivery to multiple cell types including neurons, astrocytes, and microglia in the brain. Overall, LNP-based mRNA delivery is effective in brain tissue and shows great promise for treating complex neurological disorders.

Taq DNA polymerase functions at elevated temperatures with fast conformational dynamics-regimes previously inaccessible to mechanistic, single-molecule studies. Here, single-walled carbon nanotube transistors recorded the motions of Taq molecules processing matched or mismatched template-deoxynucleotide triphosphate pairs from 22° to 85°C. By using four enzyme orientations, the whole-enzyme closures of nucleotide incorporations were distinguished from more rapid, 20-μs closures of Taq's fingers domain testing complementarity and orientation. On average, one transient closure was observed for every nucleotide binding event; even complementary substrate pairs averaged five transient closures between each catalytic incorporation at 72°C. The rate and duration of the transient closures and the catalytic events had almost no temperature dependence, leaving all of Taq's temperature sensitivity to its rate-determining open state.

Rapid climate warming is altering Arctic and alpine tundra ecosystem structure and function, including shifts in plant phenology. While the advancement of green up and flowering are well-documented, it remains unclear whether all phenophases, particularly those later in the season, will shift in unison or respond divergently to warming. Here, we present the largest synthesis to our knowledge of experimental warming effects on tundra plant phenology from the International Tundra Experiment. We examine the effect of warming on a suite of season-wide plant phenophases. Results challenge the expectation that all phenophases will advance in unison to warming. Instead, we find that experimental warming caused: (1) larger phenological shifts in reproductive versus vegetative phenophases and (2) advanced reproductive phenophases and green up but delayed leaf senescence which translated to a lengthening of the growing season by approximately 3%. Patterns were consistent across sites, plant species and over time. The advancement of reproductive seasons and lengthening of growing seasons may have significant consequences for trophic interactions and ecosystem function across the tundra.

Single-molecule measurements of protein dynamics help unveil the complex conformational changes and transitions that occur during ligand binding and catalytic processes. Using high-resolution single-molecule nanocircuit techniques, we have investigated differences in the conformational dynamics and transitions of lysozyme interacting with three ligands: peptidoglycan substrate, substrate-based chitin analogue, and indole derivative inhibitors. While processing peptidoglycan, lysozyme followed one of the two mechanistic pathways for the hydrolysis of the glycosidic bonds: a concerted mechanism inducing direct conformational changes from open to fully closed conformations or a nonconcerted mechanism involving transient pauses in intermediate conformations between the open and closed conformations. In the presence of either chitin or an indole inhibitor, lysozyme was unable to access the fully closed conformation where catalysis occurs. Instead, lysozymes' conformational closures terminated at slightly closed, "excited" conformations that were approximately one-quarter of the full hinge-bending range. With the indole inhibitor, lysozyme reached this excited conformation in a single step without any evidence of rate-liming intermediates, but the same conformational motions with chitin involved three hidden, intermediate processes and features similar to the nonconcerted peptidoglycan mechanism. The similarities suggest that these hidden processes involve attempts to accommodate imperfectly aligned polysaccharides in the active site. The results provide a detailed glimpse of the enzyme-ligand interplay at the crux of molecular recognition, enzyme specificity, and catalysis.

Hopelessness is associated with decreased physical activity (PA) and increased adverse events and death in patients with ischemic heart disease (IHD). Rates of PA in patients with IHD continue to be low in both hospital-based cardiac rehabilitation and home settings. While researchers have investigated strategies to increase PA among patients with IHD, interventions to promote PA specifically in IHD patients who report hopelessness are lacking. We describe the protocol for a NIH-funded randomized controlled trial designed to establish the effectiveness of a 6-week intervention (Heart Up!) to promote increased PA in IHD patients who report hopelessness. Participants (n = 225) are randomized to one of three groups: (1) motivational social support (MSS) from a nurse, (2) MSS from a nurse plus significant other support (SOS), or (3) attention control. Aims are to: (1) test the effectiveness of 6 weeks of MSS and MSS with SOS on increasing mean minutes per day of moderate to vigorous PA; (2) determine the effects of change in moderate to vigorous PA on hopelessness; and (3) determine if perceived social support and motivation (exercise self-regulation) mediate the effects of the intervention on PA. A total of 69 participants have been enrolled to date. The protocol has been consistently and accurately used by research personnel. We address the protocol challenges presented by the COVID-19 pandemic and steps taken to maintain fidelity to the intervention. Findings from this study could transform care for IHD patients who report hopelessness by promoting self-management of important PA goals that can contribute to better health outcomes.

BackgroundInvestigators conducting studies that include potentially suicidal individuals are obligated to develop a suicide risk management (SRM) protocol. There is little available in the literature to guide researchers in SRM protocol development.ObjectivesThe aim of the study was to describe an SRM protocol developed for a randomized controlled trial (RCT) currently enrolling cardiac patients who report moderate to severe levels of hopelessness.MethodsThe SRM protocol identifies suicidal ideation and measures ideation severity through use of the Columbia-Suicide Severity Rating Scale risk factor questions. Based on responses, study participants are deemed safe or at low, moderate, or high risk for suicide. The SRM protocol guides research staff through a plan of action based on risk level. The protocol further guides staff through a plan over the course of this prospective study-from hospital enrollment to home-based visits.ResultsResearch staff are well trained to identify suicidal ideation risk factors, initiate specific questioning about suicidal intent, determine level of risk, identify protective factors and a safe environment, and make referrals if needed. Of the 51 patients hospitalized with cardiac disease who reported moderate to severe hopelessness, 43 scored at a safe suicide risk level and 8 scored at low risk. Thirty-five of the 51 patients enrolled in the RCT. Of the 35 participants who received home visits to date, there have been three instances of low and one instance of moderate suicide risk. The SRM protocol has been consistently and accurately used by research personnel in both hospital and home settings. One modification has been made to the protocol since study activation, namely, the addition of an assessment of counseling history and encouragement of continued counseling. Booster training sessions of research staff will continue throughout the course of the RCT.DiscussionUse of the SRM protocol identifies study participants who are safe or at risk for suicide in both hospital and home settings, and research staff can refer participants accordingly.ConclusionThe SRM protocol developed for this RCT can serve as a model in the development of SRM protocols for future research in acute care, community, or home-based settings.

Global climate and land use change are causing woody plant encroachment in arctic, alpine, and arid/semi-arid ecosystems around the world, yet our understanding of the belowground impacts of this phenomenon is limited. We conducted a globally distributed field study of 13 alpine sites across four continents undergoing woody plant encroachment and sampled soils from both woody encroached and nearby herbaceous plant community types. We found that woody plant encroachment influenced soil microbial richness and community composition across sites based on multiple factors including woody plant traits, site level climate, and abiotic soil conditions. In particular, root symbiont type was a key determinant of belowground effects, as Nitrogen-fixing woody plants had higher soil fungal richness, while Ecto/Ericoid mycorrhizal species had higher soil bacterial richness and symbiont types had distinct soil microbial community composition. Woody plant leaf traits indirectly influenced soil microbes through their impact on soil abiotic conditions, primarily soil pH and C:N ratios. Finally, site-level climate affected the overall magnitude and direction of woody plant influence, as soil fungal and bacterial richness were either higher or lower in woody encroached versus herbaceous soils depending on mean annual temperature and precipitation. All together, these results document global impacts of woody plant encroachment on soil microbial communities, but highlight that multiple biotic and abiotic pathways must be considered to scale up globally from site- and species-level patterns. Considering both the aboveground and belowground effects of woody encroachment will be critical to predict future changes in alpine ecosystem structure and function and subsequent feedbacks to the global climate system.

A person's beliefs about their chronic condition (illness representations) influence health and treatment outcomes. Recently, researchers have used clustering approaches to identify subgroups with different patterns of beliefs about their illness, with some subgroups having more favorable health outcomes than others. To date, these findings have not been synthesized. The purpose of this systematic review of the literature was to synthesize results of studies that used clustering approaches to analyze illness representation in chronic disease populations, in order to characterize the clusters and their relationship to health outcomes. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines we searched CINAHL, PsycInfo, and PubMed. To be included, studies had to be (a) peer reviewed, (b) in English, (c) performing a cluster analysis (CA), latent class analysis (LCA), or latent profile analysis (LPA), (d) using only illness representation (IR) subscales to form clusters, (e) measuring illness representation with the Illness Perception Questionnaire (IPQ-R), (f) in a chronic condition sample, and (g) measuring health-related outcomes. Twelve studies were included. Across studies, the number of clusters found ranged from two to three. In all studies, an association was found between illness representation group and at least one of their health outcomes. Illness representation clusters associated with favorable outcomes usually included lower disease-related consequences, fewer symptoms, less negative emotion, and a more stable disease pattern. The results of this review indicate that the relationship between the patterns of the illness representation profiles and health outcomes transcend diseases. Additionally, some dimensions of illness representation may be more important drivers of group membership than others.

Advances in bioconjugation, the ability to link biomolecules to each other, small molecules, surfaces, and more, can spur the development of advanced materials and therapeutics. We have discovered that pyrocinchonimide, the dimethylated analogue of maleimide, undergoes a surprising transformation with biomolecules. The reaction targets amines and involves an imide transfer, which has not been previously reported for bioconjugation purposes. Despite their similarity to maleimides, pyrocinchonimides do not react with free thiols. Though both lysine residues and the N-termini of proteins can receive the transferred imide, the reaction also exhibits a marked preference for certain amines that cannot solely be ascribed to solvent accessibility. This property is peculiar among amine-targeting reactions and can reduce combinatorial diversity when many available reactive amines are available, such as in the formation of antibody-drug conjugates. Unlike amides, the modification undergoes very slow reversion under high pH conditions. The reaction offers a thermodynamically controlled route to single or multiple modifications of proteins for a wide range of applications.

Nanoscale materials provide new opportunities to interface solid-state electronics with biomolecules and biochemical activity. For example, single-walled carbon nanotubes (SWNTs) have the special property of electronic resistance that is sensitive to single electrons. We have exploited this sensitivity to build nanoelectronic biosensors that monitor the biochemical activity of individual proteins [1]. As an attached protein moves, binds, or performs catalysis, its charged amino acid sidechains induce resistance fluctuations in the SWNT device that may be monitored with microsecond resolution [2]. Recently, we have used this measurement platform for single-molecule measurements of DNA polymerases [3]. Polymerases are the key enzymes for converting single-stranded DNA to double-stranded helices, the primary step in DNA replication, amplification, and most sequencing technologies. When a polymerase processing DNA is also attached to a SWNT device, the electrical signal provides a high-resolution readout of single-nucleotide incorporations and exciting possibilities for high-density, high-throughput electronic DNA sequencing. To investigate the feasibility of electronic DNA sequencing, we have compared single-molecule transduction by DNA polymerases from three different organisms. By working with multiple families of DNA polymerases, we have tested the applicability of the electronic technique while also generating detailed records of differences among the enzymes. For example, we observe an anomalous rate variability when measuring the polymerase from the bacillus phage φ29. Base incorporation rates average 20 s-1 for most the enzymes processing single-stranded DNA templates, but rates up to 200 and 400 s-1 occurred when φ29 encountered homopolymeric sequences of poly(dT) or poly(dC), respectively. When processing poly(dA) and poly(dG) sequences, on the other hand, φ29 had bursts of activity interrupted by pauses lasting 50 to 300 s. This sequence-dependent activity illustrates one way that single-molecule methods reveal information hidden in ensemble-based techniques. Another workhorse protein in DNA sequencing technologies is the DNA polymerase derived from the thermophilic bacteria Thermus aquaticus (Taq). Anomalous stability at high temperatures makes Taq a unique enzyme for the polymerase chain reaction (PCR) and commercial amplification of DNA. In a first for single-molecule biophysics, SWNT devices have recorded Taq activity over a wide temperature range from 22 to 94 °C, including the typical PCR operating temperature of 72 °C. Even operating at this high temperature, the technique resolved Taq testing incoming nucleotides for complementarity and incorporating correct matches in the base-by-base construction of Watson-Crick pairs. The detailed recordings reveal the similarities of Taq’s operation to other, room temperature polymerases. [1] Y. Choi, et. al., Science 335, 319 (2012). [2] M. V. Akhterov, et. al., ACS Chem. Biol. 10, 1495 (2015). [3] T. J. Olsen et. al., JACS 135, 7855 (2013); O. T. Gul et. al., Biosensors 6, 29 (2016)

Purpose: Motivation declines as children reach adolescence. Poor motivation inhibits participation and engagement in language-based interventions. The purpose of this tutorial is to demonstrate how intervention can be designed to increase client motivation to participate while improving language-based literacy skills. Method: Motivation and behavior change techniques based on self-determination theory are presented, as are examples of how to integrate these techniques into contextualized language intervention with adolescent clients. Conclusion: Incorporating motivation and behavior change techniques into contextualized language interventions with adolescents promotes self-determination and motivation through satisfaction of their need for autonomy, relatedness, and competence while simultaneously addressing language-based literacy deficits.

As we transition from child to adult, we navigate the worlddifferently. In this world, many of the relationships betweenevents are unclear or uncertain because they are probabilisticin nature. We wanted to know how learning about probabilis-tic relationships changes with development and to interrogatethe underlying processes. We investigated these questions in aprobabilistic reinforcement learning task (The Butterfly Task)with 302 participants aged 8-30. We found performance in thistask increased with age through early-twenties, then stabilized.Using hierarchical Bayesian methods to fit computational rein-forcement learning models, we showed that this performanceincrease was driven by 1) an increase in learning rate (i.e. de-crease in integration time horizon); 2) a decrease in exploratorychoices. By contrast, forgetting rates did not change with age.We discuss our findings in the context of other studies and hy-potheses about adolescent brain development.

n reinforcement learning (RL) experiments, participantslearn to associate stimuli with rewarding responses. RLmodels capture such learning by estimating stimulus-responsevalues. But what is a response? RL algorithms can model anyresponse type, whether it is a basic motor action (e.g. pressinga key), or a more abstract, non-motor choice (e.g. selectingpizza at the restaurant). Are these different responses learnedthe same way? In this study, we examine differences betweenlearning a rewarding association between (1) a stimulus and amotor action and (2) two stimuli. We show that learningdiffers between these two conditions, contrary to the commonimplicit assumption that response type does not matter.Specifically, participants were slower and less accurate inlearning to select a rewarding stimulus. Using computationalmodeling, we show that the values of motor actions interferedwith the values of stimulus responses, resulting in moreincorrect choices in the latter condition.

"Mystery, Medicine, and the Magnificent Mile," the theme for the annual Midwest Reproductive Symposium International (MRSi) in Chicago, IL, captured the attention of reproductive professionals all over the world. Each year, the conference agenda encompasses emerging technologies in assisted reproduction, updates in the management of reproductive diseases, and common challenges encountered in clinical practice. The structure of the meeting, offering a mixture of lectures, panel discussions, and interactive workshops, creates a collaborative environment for physicians, geneticists, embryologists, nurses, mental health professionals, basic scientists, business administrative professionals, reproductive endocrinology and infertility fellows, and obstetrics and gynecology residents. The goal of the MRSi meeting is to provide all reproductive professionals the opportunity to exchange ideas, foster relationships, and deliver quality patient care. As the field continues to evolve, MRSi provides an exciting venue to uncover the mysteries of reproductive medicine with enthusiasm and collaboration.

Rural students are at risk for vocabulary underdevelopment and often have less access to educational resources. The purpose of this investigation was to examine the effectiveness of an Internet-based Speech/Language Pathologist (SLP)-teacher consultation to support rural teachers' vocabulary instruction to improve their students' lexical inferencing skills. The investigators probed rural fourth-graders' lexical inferencing skills three times throughout a semester. The experimental group's teachers participated in SLP-teacher consultation, while the control group's teachers did not. Although both groups demonstrated increases in lexical inferencing skills, there were significant differences in the groups' error patterns. Clinical implications of these findings are discussed.

Chronic illness affects >50% of adults in the United States and accounts for >80% of healthcare spending. The purpose of this study was to determine whether beliefs about one's chronic disease (illness representation) are associated with self-care activation, emergency department (ED) visits, or hospitalizations. Using a cross-sectional design, we recruited older adults with heart failure, chronic obstructive pulmonary disease (COPD), and chronic kidney disease. The Revised Illness Perception Questionnaire (IPQ-R) measured perceptions about disease. The Patient Activation Measure measured self-care activation. ED visits and hospitalizations were measured by self-report. IPQ-R scores were analyzed using latent profile analysis to identify subgroups. Participants included 187 adults (mean age 65 years, 54% female, 74% Black). We found three subgroups (stable, overwhelmed, and confident). Groups did not differ demographically or by disease. The stable group (few consequences, non-fluctuating pattern) had the fewest hospitalizations. The overwhelmed group (many consequences, fluctuating pattern, high negative emotion) had high hospitalizations and low self-care ability. The confident group (high disease control, well-understood) had the highest self-care ability, but also high hospitalizations. ED visits did not differ by group. We found three subgroups that differ in their illness representation and health outcomes. Findings suggest that assessing patients' illness representations may have important implications for subgroup-specific interventions.

Global climate and land use change are altering plant and soil microbial communities worldwide, particularly in arctic and alpine biomes where warming is accelerated. The widespread expansion of woody shrubs into historically herbaceous alpine plant zones is likely to interact with climate to affect soil microbial community structure and function; however, our understanding of alpine soil ecology remains limited. This study aimed to (i) determine whether the diversity and community composition of soil fungi vary across elevation gradients and to (ii) assess the impact of woody shrub expansion on these patterns. In the White Mountains of California, sagebrush (Artemisia rothrockii) shrubs have been expanding upwards into alpine areas since 1960. In this study, we combined observational field data with a manipulative shrub removal experiment along an elevation transect of alpine shrub expansion. We utilized next-generation sequencing of the ITS1 region for fungi and joint distribution modelling to tease apart effects of the environment and intracommunity interactions on soil fungi. We found that soil fungal diversity declines and community composition changes with increasing elevation. Both abiotic factors (primarily soil moisture and soil organic C) and woody sagebrush range expansion had significant effects on these patterns. However, fungal diversity and relative abundance had high spatial variation, overwhelming the predictive power of vegetation type, elevation and abiotic soil conditions at the landscape scale. Finally, we observed positive and negative associations among fungal taxa which may be important in structuring community responses to global change.

The article critiques the public/private rights framework in federal adjudication, focusing on how the distinction between public and private rights has evolved and been challenged, particularly in the context of land claims and administrative adjudication.

The predictive performance equation (PPE) is a mathematicalmodel of learning and retention that uses regularities seen inhuman learning to predict future performance. Previous research(Collins, Gluck, Walsh Krusmark & Gunzelmann, , 2016) foundthat prior data could be used to inform PPE’s free parameterswhen generating predictions of a group’s aggregate performance,allowing for more accurate initial performance predictions. Herewe investigate an extension of this methodology to predictperformance of individuals, rather than aggregate samples. Thispaper documents the results of that investigation, which is on thecritical path to the use of this cognitive technology in educationand training.

As biosensing devices shrink smaller and smaller, they approach a scale in which single molecule electronic sensing becomes possible. Here, we review the operation of single-enzyme transistors made using single-walled carbon nanotubes. These novel hybrid devices transduce the motions and catalytic activity of a single protein into an electronic signal for real-time monitoring of the protein's activity. Analysis of these electronic signals reveals new insights into enzyme function and proves the electronic technique to be complementary to other single-molecule methods based on fluorescence. As one example of the nanocircuit technique, we have studied the Klenow Fragment (KF) of DNA polymerase I as it catalytically processes single-stranded DNA templates. The fidelity of DNA polymerases makes them a key component in many DNA sequencing techniques, and here we demonstrate that KF nanocircuits readily resolve DNA polymerization with single-base sensitivity. Consequently, template lengths can be directly counted from electronic recordings of KF's base-by-base activity. After measuring as few as 20 copies, the template length can be determined with

Objective: Hopelessness is present in 27% of patients with ischaemic heart disease (IHD), can persist for 12 months and is associated with lack of physical activity (PA). No interventions have been tested to increase PA in IHD patients who report hopelessness. This study evaluated the feasibility of conducting a randomised controlled trial to investigate the effectiveness of the Heart Up! intervention, designed to reduce hopelessness through enhanced PA in IHD patients. It was hypothesised that increased PA would be identified in the intervention group. Setting: Patients were recruited from a large teaching hospital in the Midwestern USA. Data collection occurred in the patient's home at 1 and 8 weeks after hospital discharge. Methods: A three-group design was used. Eligible patients were randomised to (1) motivational social support (MSS) from a nurse, (2) MSS from a nurse with social support from a significant other support (SOS) or (3) control. MSS-only and MSS-SOS recipients received motivational interviewing followed by 6 weeks of social support text messages from a nurse. MSS-SOS participants additionally received social support text messages from a significant other. Control participants received the usual care. Feasibility outcomes included recruitment and retention rates, patient acceptability and patient satisfaction. An accelerometer measured PA. Results: Of the 156 patients screened for the study, 43 met the inclusion criteria. Of eligible patients, 69.8% (n = 30) enrolled and 67% (n = 20) completed the study. Patients in the MSS and MSS-SOS groups expressed satisfaction with the intervention components (86% with motivational interviewing, 77% with nurse texts and 100% with significant other texts). Although differences were not statistically significant, a medium effect size for change in PA was identified in the MSS-SOS group compared to the other two groups. Conclusion: Study findings demonstrate the feasibility of the "Heart Up!" intervention and support testing its efficacy in a randomised controlled trial.