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Bridge-funding by tertiary-educational institutions allows researchers to continue their research in times of funding loss. With the ever-declining funding rates for major medical research institutions in North America, and the global economic downturn, it is crucial to critically assess institutional policies surrounding the allocation of bridge-funding. We review the theoretical framework of bridge-funding decisions and present theoretical factors that determine the success of bridge-funding. We also report the results of an online survey of bridge-funding policies in major medical research institutions in North America.

Highly pathogenic avian influenza (HPAI) viruses have potential to cross species barriers and cause pandemics. Since 2022, HPAI A(H5N1) belonging to the goose/Guangdong 2.3.4.4b hemagglutinin phylogenetic clade have infected poultry, wild birds, and mammals across North America. Continued circulation in birds and infection of multiple mammalian species with strains possessing adaptation mutations increase the risk for infection and subsequent reassortment with influenza A viruses endemic in swine. We assessed the susceptibility of swine to avian and mammalian HPAI H5N1 clade 2.3.4.4b strains using a pathogenesis and transmission model. All strains replicated in the lung of pigs and caused lesions consistent with influenza A infection. However, viral replication in the nasal cavity and transmission was only observed with mammalian isolates. Mammalian adaptation and reassortment may increase the risk for incursion and transmission of HPAI viruses in feral, backyard, or commercial swine. [ABSTRACT FROM AUTHOR]

Objective : This study evaluated the effectiveness of academic screening measures in relation to parent-reported diagnoses. Design : Multicenter, retrospective cohort study including structured interviews, questionnaires, and chart reviews. Setting : Six North American cleft centers. Participants : Children (n = 391) with cleft lip and/or palate, ages 8 to 10 years of age (192 male) and their guardians were recruited during regular clinic visits. Main Outcome Measures : Parent and child ratings on the Pediatric Quality of Life Inventory (PedsQL) School Scale, child report on CleftQ School Scale, parent report on the Adaptive Behavior Assessment System-Third Edition Functional Academics (ABAS-FA) Scale and Child Behavior Checklist (CBCL) School Competency Scale, parent interview, and medical chart review. Results : Risk for concerns ranged from 12% to 41%, with higher risk reflected on the CBCL-SC compared to other measures. Males with cleft palate were consistently at the highest risk. Only 9% of the sample had a parent-reported diagnosis of a learning or language disability. Ratings from the ABAS-FA and CBCL-SC had the highest utility in identifying those with language and/or learning concerns. Conclusions : As cleft teams work to develop standardized batteries for screening and monitoring of patients, it is important to evaluate the effectiveness of measures in identifying those at highest risk. When screening for language and learning disorders, questions related to potential academic struggles, such as increased school effort or increased school distress, are most useful. Referrals for follow-up evaluation are recommended for those identified at high risk. [ABSTRACT FROM AUTHOR]

We sought to examine current practices and changes in practice regarding initial counseling for families of patients with hypoplastic left heart syndrome (HLHS) given the evolution of options and outcomes over time. Counseling (Norwood with Blalock-Taussig-Thomas shunt (NW-BTT), NW with right ventricle to pulmonary artery conduit (NW-RVPA), hybrid palliation, heart transplantation, or non-intervention/hospice (NI)) for patients with HLHS were queried via questionnaire of pediatric care professionals in 2021 and compared to identical questionnaire from 2011. Of 322 respondents in 2021 (39% female), 299 respondents were cardiologists (92.9%), 17cardiothoracic surgeons (5.3%), and 6 were nurse practitioners (1.9%). Respondents were largely from North America (96.9%). In 2021, NW-RVPA procedure was the preferred palliation for standard risk HLHS patient (61%) and was preferred across all US regions (p < 0.001). NI was offered as an option by 71.4% of respondents for standard risk patients and was the predominant strategy for patients with end-organ dysfunction, chromosomal abnormality, and prematurity (52%, 44%, and 45%, respectively). The hybrid procedure was preferred for low birth-weight infants (51%). In comparison to the identical 2011 questionnaire (n = 200), the NW-RVPA was endorsed more in 2021 (61% vs 52%, p = 0.04). For low birth-weight infants, hybrid procedure was more recommended than in 2011 (51% vs 21%, p < 0.001). The NW-RVPA operation is the most recommended strategy throughout the US for infants with HLHS. The hybrid procedure for low birth-weight infants is increasingly recommended. NI continues to be offered even in standard risk patients with HLHS. [ABSTRACT FROM AUTHOR]

Management of waterfowl that migrate seasonally across North America occurs within four flyways that were delineated in the early 1900s to include the annual movements of populations. Movements may have changed over the past century since the administrative flyways were established, and may do so while management plans are in use, so information about transitions among flyways through time can illustrate how management assumptions may change. Today there are more than 12 million records from 60 years of migratory waterfowl band recoveries to assess adaptive management approaches that will be most effective when they account for movements within and between flyways. We examined how much the movement of North American waterfowl occurs between flyways, whether those movements have changed through time, and whether movements of mallards are representative of multiple species, as suggested by current harvest management strategies. We estimated the probability a duck would transition from one flyway to another and the strength of migratory connectivity (MC) for each species within and among flyways. We used capture–mark–recovery models to estimate population‐specific movement within and among flyways (transition probabilities) for 15 migratory waterfowl species that were banded during breeding and recovered during winter. We developed new functionality in the R package MigConnectivity to estimate the species‐specific strength of MC using transition probability samples from the capture–mark–recovery models. We found the regular movement of duck populations among flyways, overall weak MC, and no consistent change in migratory movements through time. Mallard movements were median among all duck species, but significantly different from many species, particularly diving ducks. Despite the significant movement between flyways, our work suggests flyway management of waterfowl matches many of the seasonal movements of these species when considering mid‐continent flyway management. We recommend models accounting for all transition probabilities between populations and regularly estimating harvest derivations, transition probabilities, and MC metrics to verify that the current movements match model assumptions. [ABSTRACT FROM AUTHOR]

Human‐induced salinization increasingly threatens inland waters; yet we know little about the multifaceted response of lake communities to salt contamination. By conducting a coordinated mesocosm experiment of lake salinization across 16 sites in North America and Europe, we quantified the response of zooplankton abundance and (taxonomic and functional) community structure to a broad gradient of environmentally relevant chloride concentrations, ranging from 4 to ca. 1400 mg Cl− L−1. We found that crustaceans were distinctly more sensitive to elevated chloride than rotifers; yet, rotifers did not show compensatory abundance increases in response to crustacean declines. For crustaceans, our among‐site comparisons indicate: (1) highly consistent decreases in abundance and taxon richness with salinity; (2) widespread chloride sensitivity across major taxonomic groups (Cladocera, Cyclopoida, and Calanoida); and (3) weaker loss of functional than taxonomic diversity. Overall, our study demonstrates that aggregate properties of zooplankton communities can be adversely affected at chloride concentrations relevant to anthropogenic salinization in lakes. [ABSTRACT FROM AUTHOR]

Influenza A viruses (IAVs) of the H1N1 classical swine lineage became endemic in North American swine following the 1918 pandemic. Additional human-to-swine transmission events after 1918, and a spillover of H1 viruses from wild birds in Europe, potentiated a rapid increase in genomic diversity via reassortment between introductions and the endemic classical swine lineage. To determine mechanisms affecting reassortment and evolution, we conducted a phylogenetic analysis of N1 and paired HA swine IAV genes in North America between 1930 and 2020. We described fourteen N1 clades within the N1 Eurasian avian lineage (including the N1 pandemic clade), the N1 classical swine lineage, and the N1 human seasonal lineage. Seven N1 genetic clades had evidence for contemporary circulation. To assess antigenic drift associated with N1 genetic diversity, we generated a panel of representative swine N1 antisera and quantified the antigenic distance between wild-type viruses using enzyme-linked lectin assays and antigenic cartography. Within the N1 genes, the antigenic similarity was variable and reflected shared evolutionary history. Sustained circulation and evolution of N1 genes in swine had resulted in a significant antigenic distance between the N1 pandemic clade and the classical swine lineage. Between 2010 and 2020, N1 clades and N1–HA pairings fluctuated in detection frequency across North America, with hotspots of diversity generally appearing and disappearing within 2 years. We also identified frequent N1–HA reassortment events (n = 36), which were rarely sustained (n = 6) and sometimes also concomitant with the emergence of new N1 genetic clades (n = 3). These data form a baseline from which we can identify N1 clades that expand in range or genetic diversity that may impact viral phenotypes or vaccine immunity and subsequently the health of North American swine. [ABSTRACT FROM AUTHOR]

Demographic compensation—the opposing responses of vital rates along environmental gradients—potentially delays anticipated species' range contraction under climate change, but no consensus exists on its actual contribution. We calculated population growth rate (λ) and demographic compensation across the distributional ranges of 81 North American tree species and examined their responses to simulated warming and tree competition. We found that 43% of species showed stable population size at both northern and southern edges. Demographic compensation was detected in 25 species, yet 15 of them still showed a potential retraction from southern edges, indicating that compensation alone cannot maintain range stability. Simulated climatic warming caused larger decreases in λ for most species and weakened the effectiveness of demographic compensation in stabilising ranges. These findings suggest that climate stress may surpass the limited capacity of demographic compensation and pose a threat to the viability of North American tree populations. [ABSTRACT FROM AUTHOR]

Excellent outcomes for patients with Wilms' tumour (WT), >90% for all stages together, have been achieved through researching WT in multicentre and multinational trials and studies in the last 50 years, led by two major groups—the International Society of Paediatric Oncology (SIOP) and the Children's Oncology Group (COG) (previously the National Wilms' Tumour Study Group). Despite the two groups having different approaches, the survival outcomes are remarkably similar. In general, in the SIOP approach, which is followed in Europe and most other countries around the world, patients are first treated with preoperative chemotherapy; this is followed by surgery and, if necessary, postoperative chemotherapy and radiotherapy. In the COG approach, which is mainly followed in North America, patients are treated with upfront surgery, followed, if necessary, by postoperative chemotherapy and radiotherapy. In both groups, postoperative treatment primarily depends on tumour histological classification and stage, although, in recent studies, other prognostic factors have also been included (tumour volume, response to preoperative chemotherapy, and molecular markers). Owing to separate initial treatments, there are differences in histological assessment and subtyping of WT, and, more importantly, in staging criteria. In this review, we discuss the similarities and differences between the two groups in order to help pathologists who are dealing with WT to understand and follow the pathological protocol that is appropriate for a particular case, because, in many centres, both approaches may be followed, depending on individual case/patient circumstances. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to evaluate possible relationships between number of surgeries and parent ratings of academic functioning among children with isolated oral clefts. Design: Multicenter, retrospective cohort study including structured interviews, questionnaires, and chart reviews. Setting: Completion of questionnaires occurred during clinical visits at 6 different cleft centers across North America. Participants: Parents of 285 children with isolated clefts of the lip and/or palate, aged 8 to 10 years old, participated in structured interviews and completed questionnaires regarding the academic and behavioral functioning of their children. Main Outcome Measures: Parent interview and medical chart review of number of surgeries to date and parent ratings on the Adaptive Behavior Assessment System, Third Edition-Functional Academics Scale (ABAS-FA) and Child Behavior Checklist (CBCL) Total Competency Scale. Results: Parent ratings of ABAS-FA were at or above normative expectations, while ratings across CBCL Competency Scales were lower than normative expectations. Socioeconomic status (SES), age, and race were consistent predictors of parent ratings (higher SES, older age, and Caucasian race were associated with better functioning). Number of surgeries did not add significantly to academic ratings but did significantly contribute to ratings of social and activity participation. Patients with more surgeries were rated with lower functioning in these domains. Conclusions: Findings do not support a connection between number of surgeries and later ratings of academic functioning but do support a connection to social and activity involvement. Recommendations for conducting direct studies of the connection between surgeries and academic functioning as well as clinical considerations for surgeries and impact on social and activity involvement are discussed. [ABSTRACT FROM AUTHOR]

Populations of wild and managed pollinators are declining in North America, and causes include increases in disease pressure and decreases in flowering resources. Tallgrass prairies can provide floral resources for managed honey bees (Hymenoptera: Apidae, Apis mellifera Linnaeus) and wild bees. Honey bees kept near prairies may compete with wild bees for floral resources, and potentially transfer viral pathogens to wild bees. Measurements of these potential interactions are lacking, especially in the context of native habitat conservation. To address this, we assessed abundance and richness of wild bees in prairies with and without honey bee hives present, and the potential spillover of several honey bee viruses to bumble bees (Hymenoptera: Apidae, Bombus Latrielle). We found no indication that the presence of honey bee hives over 2 yr had a negative effect on population size of wild bee taxa, though a potential longer-term effect remains unknown. All levels of viruses quantified in bumble bees were lower than those observed in honey bees. Higher levels of deformed wing virus and Israeli acute paralysis virus were found in Bombus griseocollis DeGeer (Hymenoptera: Apidae) collected at sites with hives than those without hives. These data suggest that the presence of honey bees in tallgrass prairie could increase wild bee exposure to viruses. Additional studies on cross-species transmission of viruses are needed to inform decisions regarding the cohabitation of managed bees within habitat utilized by wild bees. [ABSTRACT FROM AUTHOR]

Aim: Climate change poses significant challenges for tree species, which are slow to adapt and migrate. Insight into genetic and phenotypic variation under current landscape conditions can be used to gauge persistence potential to future conditions and determine conservation priorities, but landscape effects have been minimally tested in trees. Here, we use Pinus contorta, one of the most widely distributed conifers in North America, to evaluate the influence of landscape heterogeneity on genetic structure as well as the magnitude of local adaptation versus phenotypic plasticity in a widespread tree species. Location: Western North America. Methods: We paired landscape genetics with fully reciprocal in situ common gardens to evaluate landscape influence on neutral and adaptive variation across all subspecies of P. contorta. Results: Landscape barriers alone play a minor role in limiting gene flow, creating marginal geographically‐based structure. Local climate determines population performance, with survival highest at home but growth greatest in mild climates (e.g., warm, wet). Survival of two of the three populations tested was consistent with patterns of local adaptation documented for P. contorta, while growth was indicative of plasticity for populations grown under novel conditions and suggesting that some populations are not currently occupying their climatic optimum. Main Conclusions: Our findings provide insight into the role of the landscape in shaping population genetic structure in a widespread tree species as well as the potential response of local populations to novel conditions, knowledge critical to understanding how widely distributed species may respond to climate change. Geographically based genetic structure and reduced survival under water‐limited conditions may make some populations of widespread tree species more vulnerable to local maladaptation and extirpation. However, genetically diverse and phenotypically plastic populations of widespread trees, such as many of the P. contorta populations sampled and tested here, likely possess high persistence potential. [ABSTRACT FROM AUTHOR]

Horses are a highly mobile population, with many travelling locally, nationally, and internationally to participate in shows and sporting events. However, the nature and extent of these movements, as well as the potential impact they may have on disease introduction and spread, is not well documented. The objective of this study was to characterise the movement network of a sample of horses in Ontario, Canada, over a 7-month equestrian season. Horse owners (n = 141) documented their travel patterns with their horse(s) (n = 330) by completing monthly online questionnaires between May and November 2015. Directed networks were constructed to represent horse movements in 1-month time periods. A total of 1754 horse movements met the inclusion criteria for analysis. A variety of location types were included in each monthly network, with many including non-facilities such as parks, trails, and private farms. Only 34.3% of competitions attended by participants during the study period were regulated by an official equestrian organisation. Comparisons of the similarity between monthly networks indicated that participants did not travel to the same locations each month, and the most connected locations varied between consecutive months. While the findings should not be generalized to the wider horse population, they have provided greater insight into the nature and extent of observed horse movement patterns. The results support the need to better understand the variety of locations to which horses can travel in Ontario, as different types of locations may have different associated risks of disease introduction and spread. [ABSTRACT FROM AUTHOR]

We report a first record of the widely invasive bryozoan Bugula neritina in Ketchikan, Alaska (USA), on Revillagigedo Island (southeast Alaska). This represents the northernmost record of this fouling organism in the northeast Pacific Ocean. We also report a new occurrence of the solitary ascidian Ciona savignyi not found in Alaska since 1903, along with recent occurrences of the invasive colonial ascidians Botryllus schlosseri and Botrylloides violaceus in new localities. The high level of vessel traffic in this region and the precedent for historical ship-borne invasions worldwide suggest that future population growth and establishment of these taxa in the Ketchikan area could set the stage for further poleward range expansion, highlighting the need for continued monitoring. [ABSTRACT FROM AUTHOR]

Lake surface water temperatures are warming worldwide, raising concerns about the future integrity of valuable lake ecosystem services. In contrast to surface water temperatures, we know far less about what is happening to water temperature beneath the surface, where most organisms live. Moreover, we know little about which characteristics make lakes more or less sensitive to climate change and other environmental stressors. We examined changes in lake thermal structure for 231 lakes across northeastern North America (NENA), a region with an exceptionally high density of lakes. We determined how lake thermal structure has changed in recent decades (1975-2012) and assessed which lake characteristics are related to changes in lake thermal structure. In general, NENA lakes had increasing near-surface temperatures and thermal stratification strength. On average, changes in deepwater temperatures for the 231 lakes were not significantly different than zero, but individually, half of the lakes experienced warming and half cooling deepwater temperature through time. More transparent lakes (Secchi transparency >5 m) tended to have higher near-surface warming and greater increases in strength of thermal stratification than less transparent lakes. Whole-lake warming was greatest in polymictic lakes, where frequent summer mixing distributed heat throughout the water column. Lakes often function as important sentinels of climate change, but lake characteristics within and across regions modify the magnitude of the signal with important implications for lake biology, ecology and chemistry. [ABSTRACT FROM AUTHOR]

The use of natural products (NPs), including herbal medicines and other dietary supplements, by North Americans continues to increase across all age groups. This population has access to conventional medications, with significant polypharmacy observed in older adults. Thus, the safety of the interactions between multi-ingredient NPs and drugs is a topic of paramount importance. Considerations such as history of safe use, literature data from animal toxicity and human clinical studies, and NP constituent characterization would provide guidance on whether to assess NP-drug interactions experimentally. The literature is replete with reports of various NP extracts and constituents as potent inhibitors of drug metabolizing enzymes, and transporters. However, without standard methods for NP characterization or in vitro testing, extrapolating these reports to clinically-relevant NP-drug interactions is difficult. This lack of a clear definition of risk precludes clinicians and consumers from making informed decisions about the safety of taking NPs with conventional medications. A framework is needed that describes an integrated robust approach for assessing NP-drug interactions; and, translation of the data into formulation alterations, dose adjustment, labelling, and/or post-marketing surveillance strategies. A session was held at the 41st Annual Summer Meeting of the Toxicology Forum in Colorado Springs, CO, to highlight the challenges and critical components that should be included in a framework approach. [ABSTRACT FROM AUTHOR]

The concept of 'natural' populations is a foundation of modern ecology and conservation, with a large body of theoretical literature using these discrete demographic units to understand population dynamics and prioritize conservation strategies. To date, there are currently no objective methods for empirically delineating large-scale population boundaries using demographic data., We present a novel approach for using large-scale, citizen-science monitoring data to quantify geographic structure in trend and abundance and identify distinct natural populations. We demonstrate this approach by delineating populations of eight passerine species using data collected as part of the North American Breeding Bird Survey., Our approach was able to identify geographic structure in both trend and abundance and to delineate distinct populations for all eight species. An independent validation of three species indicated this demographic variation was reflected in underlying vital rates., Synthesis and applications. Natural populations are biologically based alternatives to the traditional geographically defined units that can improve the ability of researchers and managers to quantify spatial variation in population dynamics. Our analysis of natural population structure in breeding songbirds demonstrates that species can show substantial geographic variation in population attributes and underlying demography. We recommend managers define spatial units using natural populations when setting regional population objectives for both single and multispecies conservation plans. [ABSTRACT FROM AUTHOR]

Until recently, the little brown bat (Myotis lucifugus) was one of the most common bat species in North America. However, this species currently faces a significant threat from the emerging fungal disease white-nose syndrome (WNS). The aims of this study were to examine the population genetic structure of M. lucifugus hibernating colonies in Pennsylvania (PA) and West Virginia (WV), and to determine whether that population structure may have influenced the pattern of spread of WNS. Samples were obtained from 198 individuals from both uninfected and recently infected colonies located at the crest of the disease front. Both mitochondrial (636bp of cytochrome oxidase I) and nuclear (8 microsatellites) loci were examined. Although no substructure was evident from nuclear DNA, female-mediated gene flow was restricted between hibernacula in western PA and the remaining colonies in eastern and central PA and WV. This mitochondrial genetic structure mirrors topographic variation across the region: 3 hibernating colonies located on the western Appalachian plateau were significantly differentiated from colonies located in the central mountainous and eastern lowland regions, suggesting reduced gene flow between these clusters of colonies. Consistent with the hypothesis that WNS is transmitted primarily through bat-to-bat contact, these same 3 hibernating colonies in westernmost PA remained WNS-free for 1–2 years after the disease had swept through the rest of the state, suggesting that female migration patterns may influence the spread of WNS across the landscape. [ABSTRACT FROM AUTHOR]

The invasive emerald ash borer ( EAB) beetle is a significant threat to the survival of North American ash. In previous work, we identified putative biochemical and molecular markers of constitutive EAB resistance in Manchurian ash, an Asian species co-evolved with EAB. Here, we employed high-throughput high-performance liquid chromatography with photodiode array detection and mass spectrometry ( HPLC-PDA- MS) to characterize the induced response of soluble phloem phenolics to EAB attack in resistant Manchurian and susceptible black ash under conditions of either normal or low water availability, and the effects of water availability on larval performance. Total larval mass per tree was lower in Manchurian than in black ash. Low water increased larval numbers and mean larval mass overall, but more so in Manchurian ash. Low water did not affect levels of phenolics in either host species, but six phenolics decreased in response to EAB. In both ashes, pinoresinol A was induced by EAB, especially in Manchurian ash. Pinoresinol A and pinoresinol B were negatively correlated with each other in both species. The higher accumulation of pinoresinol A in Manchurian ash after attack may help explain the resistance of this species to EAB, but none of the responses measured here could explain increased larval performance in trees subjected to low water availability. [ABSTRACT FROM AUTHOR]

The emerald ash borer (Agrilus planipennis Fairmaire, EAB) is an alien, invasive wood-boring insect that is responsible for killing millions of ash trees since its discovery in North America in 2002. All North American ash species (Fraxinus spp.) that EAB has encountered have shown various degrees of susceptibility, while Manchurian ash (Fraxinus mandshurica Ruprecht), which shares a co-evolutionary history with this insect, is resistant. Recent studies have looked into constitutive resistance mechanisms in Manchurian ash, concentrating on the secondary phloem, which is the feeding substrate for the insect. In addition to specialized metabolism and defense-related components, primary metabolites and nutritional summaries can also be important to understand the feeding behavior of insect herbivores. Here, we have compared the nutritional characteristics (water content, total protein, free amino acids, total soluble sugars and starch, percent carbon and nitrogen, and macro- and micronutrients) of outer bark and phloem from black, green, white and Manchurian ash to determine their relevance to resistance or susceptibility to EAB. Water content and concentrations of Al, Ba, Cu, Fe, K, Li, tryptophan and an unknown compound were found to separate black and Manchurian ash from green and white ash in a principal component analysis (PCA), confirming their phylogenetic placements into two distinct clades. The traits that distinguished Manchurian ash from black ash in the PCA were water content and concentrations of total soluble sugars, histidine, lysine, methionine, ornithine, proline, sarcosine, tyramine, tyrosol, Al, Fe, K, Na, V and an unknown compound. However, only proline, tyramine and tyrosol were significantly different, and higher, in Manchurian ash than in black ash. [ABSTRACT FROM AUTHOR]

Aim Beringia, the unglaciated region encompassing the former Bering land bridge, as well as the land between the Lena and Mackenzie rivers, is recognized as an important refugium for arctic plants during the last ice age. Compelling palaeobotanical evidence also supports the presence of small populations of boreal trees within Beringia during the Last Glacial Maximum. The occurrence of balsam poplar ( Populus balsamifera) in Beringia provides a unique opportunity to assess the implications of persistence in a refugium on present-day genetic diversity for this boreal tree species. Location North America. Methods We sequenced three variable non-coding regions of the chloroplast genome (cpDNA) from 40 widely distributed populations of balsam poplar across its North American range. We assessed patterns of genetic diversity, geographic structure and historical demography between glaciated and unglaciated regions of the balsam poplar's range. We also utilized a coalescent model to test for divergence between regions. Results Levels of genetic diversity were consistently greater for populations at the southern margin (θW = 0.00122) than in the central (θW = 0.00086) or northern (θW = 0.00034) regions of the current distribution of balsam poplar, and diversity decreased with increasing latitude ( R2 = 0.49, P < 0.01). We detected low, but significant, structure ( FCT = 0.05, P = 0.05), among regions of P. balsamifera's distribution. The cpDNA genealogy was shallow, however, showing an absence of highly differentiated chloroplast haplotypes. Coalescent analyses supported a model of divergence between the southern ice margin and the northern unglaciated region of balsam poplar's distribution, but analyses of other regional comparisons did not converge. Main conclusions The palaeobotanical record supports the presence of a Beringian refugium for balsam poplar, but we were unable to definitively identify the presence of known refugial populations based on genetic data alone. Balsam poplar populations from Beringia are not a significant reservoir of cpDNA diversity today. Unique alleles that may have been present in the small, isolated populations that survived within Beringia were probably lost through genetic drift or swamped by post-glacial, northward migration from populations south of the ice sheets. [ABSTRACT FROM AUTHOR]

A literary criticism of the book "Five Miles Away, A World Apart" by James Ryan is presented. It discusses the division of schools based on income, class, and race and looks at Ryan's suggestion that income integration will promote racial diversity within schools in the U.S. The author argues that the book's focus on academic achievement ignores parents' fear of antisocial attitudes and disruptive behaviors of poor and minority students.

Abstract: The gene constellation of the 2009 pandemic A/H1N1 virus is a unique combination from swine influenza A viruses (SIV) of North American and Eurasian lineages, but prior to April 2009 had never before been identified in swine or other species. Although its hemagglutinin gene is related to North American H1 SIV, it is unknown if vaccines currently used in U.S. swine would cross-protect against infection with the pandemic A/H1N1. The objective of this study was to evaluate the efficacy of inactivated vaccines prepared with North American swine influenza viruses as well as an experimental homologous A/H1N1 vaccine to prevent infection and disease from 2009 pandemic A/H1N1. All vaccines tested provided partial protection ranging from reduction of pneumonia lesions to significant reduction in virus replication in the lung and nose. The multivalent vaccines demonstrated partial protection; however, none was able to prevent all nasal shedding or clinical disease. An experimental homologous 2009 A/H1N1 monovalent vaccine provided optimal protection with no virus detected from nose or lung at any time point in addition to amelioration of clinical disease. Based on cross-protection demonstrated with the vaccines evaluated in this study, the U.S. swine herd likely has significant immunity to the 2009 A/H1N1 from prior vaccination or natural exposure. However, consideration should be given for development of monovalent homologous vaccines to best protect the swine population thus limiting shedding and the potential transmission of 2009 A/H1N1 from pigs to people. [Copyright &y& Elsevier]

Background: The norovirus group (NVG) of caliciviruses are the etiological agents of most institutional outbreaks of gastroenteritis in North America and Europe. Identification of NVG is complicated by the non-culturable nature of this virus, and the absence of a diagnostic gold standard makes traditional evaluation of test characteristics problematic. Methods: We evaluated 189 specimens derived from 440 acute gastroenteritis outbreaks investigated in Ontario in 2006-07. Parallel testing for NVG was performed with real-time reversetranscriptase polymerase chain reaction (RT2-PCR), enzyme immunoassay (EIA) and electron microscopy (EM). Test characteristics (sensitivity and specificity) were estimated using latent class models and composite reference standard methods. The practical implications of test characteristics were evaluated using binomial probability models. Results: Latent class modelling estimated sensitivities of RT[sub2]-PCR, EIA, and EM as 100%, 86%, and 17% respectively; specificities were 84%, 92%, and 100%; estimates obtained using a composite reference standard were similar. If all specimens contained norovirus, RT[sub2]-PCR or EIA would be associated with > 99.9% likelihood of at least one test being positive after three specimens tested. Testing of more than 5 true negative specimens with RT[sub2]-PCR would be associated with a greater than 50% likelihood of a false positive test. Conclusion: Our findings support the characterization of EM as lacking sensitivity for NVG outbreaks. The high sensitivity of RT[sub2]-PCR and EIA permit identification of NVG outbreaks with testing of limited numbers of clinical specimens. Given risks of false positive test results, it is reasonable to limit the number of specimens tested when RT[sub2]-PCR or EIA are available. [ABSTRACT FROM AUTHOR]

African painted dogs (Lycaon pictus, APD) are highly endangered, with fewer than 7000 remaining in nature. Captive breeding programs can preserve a genetically diverse population and provide a source of individuals for reintroductions. However, most programs are initiated from few founders and suffer from low genetic diversity and inbreeding. The aims of this study were to use molecular markers to assess genetic variation, inbreeding, and relatedness among APDs in the North American captive population, to use these data to realign studbook records, and to compare these data to wild populations and to the European captive population to facilitate the development of a global management plan. We sequenced mitochondrial and major histocompatibility (MHC) class II loci and genotyped 14 microsatellite loci from 109 APDs from 34 institutions in North America. We identified three likely studbook errors and resolved ten cases of uncertain paternity. Overall, microsatellite heterozygosity was higher than reported in Europe, but effective population size estimates were lower. Mitochondrial sequence variation was extremely limited, and there were fewer MHC haplotypes than in Europe or the wild. Although the population did not show evidence of significant inbreeding overall, several individuals shared high relatedness values, which should be incorporated into future breeding programs. [ABSTRACT FROM AUTHOR]

Simple Summary: Honey bees rely on pollen and nectar to provide nutrients to support their yearly colony cycle. Specifics of the cycle differ among geographic regions as do the species of flowering plants and the nutrients they provide. We examined responses of honey bees from two different queen lines fed pollens from locations that differed in floral species composition and yearly colony cycles. We detected differences between the queen lines in the amount of pollen they consumed and the size of their hypopharyngeal glands (HPG). There were also seasonal differences between the nutrient composition of pollens. Spring pollens collected from colonies in both locations had higher amino and fatty acid concentrations than fall pollens. There also were seasonal differences in responses to the pollens consumed by bees from both queen lines. Bees consumed more spring than fall pollen, but digested less of it so that bees consumed more protein from fall pollens. Though protein consumption was higher with fall pollen, HPG were larger in spring bees. Honey bee colonies have a yearly cycle that is supported nutritionally by the seasonal progression of flowering plants. In the spring, colonies grow by rearing brood, but in the fall, brood rearing declines in preparation for overwintering. Depending on where colonies are located, the yearly cycle can differ especially in overwintering activities. In temperate climates of Europe and North America, colonies reduce or end brood rearing in the fall while in warmer climates bees can rear brood and forage throughout the year. To test the hypothesis that nutrients available in seasonal pollens and honey bee responses to them can differ we analyzed pollen in the spring and fall collected by colonies in environments where brood rearing either stops in the fall (Iowa) or continues through the winter (Arizona). We fed both types of pollen to worker offspring of queens that emerged and open mated in each type of environment. We measured physiological responses to test if they differed depending on the location and season when the pollen was collected and the queen line of the workers that consumed it. Specifically, we measured pollen and protein consumption, gene expression levels (hex 70, hex 110, and vg) and hypopharyngeal gland (HPG) development. We found differences in macronutrient content and amino and fatty acids between spring and fall pollens from the same location and differences in nutrient content between locations during the same season. We also detected queen type and seasonal effects in HPG size and differences in gene expression between bees consuming spring vs. fall pollen with larger HPG and higher gene expression levels in those consuming spring pollen. The effects might have emerged from the seasonal differences in nutritional content of the pollens and genetic factors associated with the queen lines we used. [ABSTRACT FROM AUTHOR]

Dreissenid mussels (including the zebra mussel Dreissena polymorpha and the quagga mussel D. rostriformis) are among the world's most notorious invasive species, with large and widespread ecological and economic effects. However, their long‐term population dynamics are poorly known, even though these dynamics are critical to determining impacts and effective management. We gathered and analyzed 67 long‐term (>10 yr) data sets on dreissenid populations from lakes and rivers across Europe and North America. We addressed five questions: (1) How do Dreissena populations change through time? (2) Specifically, do Dreissena populations decline substantially after an initial outbreak phase? (3) Do different measures of population performance (biomass or density of settled animals, veliger density, recruitment of young) follow the same patterns through time? (4) How do the numbers or biomass of zebra mussels or of both species combined change after the quagga mussel arrives? (5) How does body size change over time? We also considered whether current data on long‐term dynamics of Dreissena populations are adequate for science and management. Individual Dreissena populations showed a wide range of temporal dynamics, but we could detect only two general patterns that applied across many populations: (1) Populations of both species increased rapidly in the first 1–2 yr after appearance, and (2) quagga mussels appeared later than zebra mussels and usually quickly caused large declines in zebra mussel populations. We found little evidence that combined Dreissena populations declined over the long term. Different measures of population performance were not congruent; the temporal dynamics of one life stage or population attribute cannot generally be accurately inferred from the dynamics of another. We found no consistent patterns in the long‐term dynamics of body size. The long‐term dynamics of Dreissena populations probably are driven by the ecological characteristics (e.g., predation, nutrient inputs, water temperature) and their temporal changes at individual sites rather than following a generalized time course that applies across many sites. Existing long‐term data sets on dreissenid populations, although clearly valuable, are inadequate to meet research and management needs. Data sets could be improved by standardizing sampling designs and methods, routinely collecting more variables, and increasing support. [ABSTRACT FROM AUTHOR]

Novel H3N2 influenza viruses (H3N2v) containing seven genome segments from swine lineage triple-reassortant H3N2 viruses and a 2009 pandemic H1N1 (H1N1pdm09) matrix protein segment (pM) were isolated from 12 humans in the United States between August and December 2011. To understand the evolution of these novel H3N2 viruses in swine and humans, we undertook a phylogenetic analysis of 674 M sequences and 388 HA and NA sequences from influenza viruses isolated from North American swine during 2009-2011, as well as HA, NA, and M sequences from eight H3N2v viruses isolated from humans. We identified 34 swine influenza viruses (termed rH3N2p) with the same combination of H3, N2, and pM segments as the H3N2v viruses isolated from humans. Notably, these rH3N2p viruses were generated in swine via reassortment events between H3N2 viruses and the pM segment approximately 4 to 10 times since 2009. The pM segment has also reassorted with multiple distinct lineages of H1 virus, especially H1d viruses. Importantly, the N2 segment of all H3N2v viruses isolated from humans is derived from a genetically distinct N2 lineage that has circulated in swine since being acquired by reassortment with seasonal human H3N2 viruses in 2001-2002, rather than from the N2 that is associated with the 1998 H3N2 swine lineage. The identification of this N2 variant may have implications for influenza vaccine design and the potential pandemic threat of H3N2v to human age groups with differing levels of prior exposure and immunity. [ABSTRACT FROM AUTHOR]

There are numerous emergency department visits in the United States for all types of marine animal injuries each year. These injuries may result in significant morbidity or mortality if not managed appropriately. Accurate identification of the offending species, thorough wound hygiene, and judicious use of antibiotics are important for preventing infections. This review aims to describe management strategies and antimicrobial considerations for nonmammalian marine vertebrate penetrating trauma in North America, the Caribbean, and Hawaii. A literature search was performed to identify studies on this subject. This literature consisted of clinical case reports and case series. Reports extracted included those on sharks, barracuda, eels, catfish, stingrays, lionfish, stonefish, and scorpionfish. The majority of reported trauma occurred to beachgoers, fishermen, or commercial aquarium employees who routinely handle these animals. Injury patterns depended on the species but most commonly affected the lower extremities. Infections were seen from saltwater bacteria, human skin flora, or marine animal oral flora. After thorough wound irrigation and exploration, most authors recommended prophylactic antimicrobials to cover Vibrio species, in addition to other gram-negative and gram-positive species. The literature is notable for the lack of controlled studies. Some authors recommended radiographic and/or ultrasonographic imaging to identify retained foreign bodies, such as spines, sand, or teeth., (Copyright © 2022. Published by Elsevier Inc.)

Human-induced salinization caused by the use of road deicing salts, agricultural practices, mining operations, and climate change is a major threat to the biodiversity and functioning of freshwater ecosystems. Yet, it is unclear if freshwater ecosystems are protected from salinization by current water quality guidelines. Leveraging an experimental network of land-based and in-lake mesocosms across North America and Europe, we tested how salinization-indicated as elevated chloride (Cl - ) concentration-will affect lake food webs and if two of the lowest Cl - thresholds found globally are sufficient to protect these food webs. Our results indicated that salinization will cause substantial zooplankton mortality at the lowest Cl - thresholds established in Canada (120 mg Cl - /L) and the United States (230 mg Cl - /L) and throughout Europe where Cl - thresholds are generally higher. For instance, at 73% of our study sites, Cl - concentrations that caused a ≥50% reduction in cladoceran abundance were at or below Cl - thresholds in Canada, in the United States, and throughout Europe. Similar trends occurred for copepod and rotifer zooplankton. The loss of zooplankton triggered a cascading effect causing an increase in phytoplankton biomass at 47% of study sites. Such changes in lake food webs could alter nutrient cycling and water clarity and trigger declines in fish production. Current Cl - thresholds across North America and Europe clearly do not adequately protect lake food webs. Water quality guidelines should be developed where they do not exist, and there is an urgent need to reassess existing guidelines to protect lake ecosystems from human-induced salinization., Competing Interests: The authors declare no competing interest.

Campylobacter is the second leading cause of foodborne illness in the United States. Although many food production animals carry Campylobacter as commensal bacteria, consumption of poultry is the main source of human infection. Previous research suggests that the biology of Campylobacter results in complete flock colonization within days. However, a recent systematic review found that the on-farm prevalence of Campylobacter varies widely, with some flocks reporting low prevalence. We hypothesized that the low prevalence of Campylobacter in some flocks may be driven by a delayed introduction of the pathogen. The objectives of this study were to (a) develop a deterministic compartmental model that represents the biology of Campylobacter, (b) identify the parameter values that best represent the natural history of the pathogen in poultry flocks and (c) examine the possibility that a delayed introduction of the pathogen is sufficient to replicate the observed low prevalence examples documented in the literature. A deterministic compartmental model was developed to examine the dynamics of Campylobacter in chicken flocks over a 56-day time period prior to movement to the abattoir. The model outcome of interest was the final population prevalence of Campylobacter at day 56. The resulting model that incorporated a high transmission rate (β = 1.04) was able to reproduce the wide range of prevalence estimates observed in the literature when pathogen introduction time is varied. Overall, we established that the on-farm transmission rate of Campylobacter in chickens is likely high and can result in complete colonization of a flock when introduced early. However, delaying the time at which the pathogen enters the flock can reduce the prevalence observed at 56 days. These results highlight the importance of enforcing strict biosecurity measures to prevent or delay the introduction of the bacteria to a flock., (© 2021 Wiley-VCH GmbH.)

Objectives: The objective of this study was to determine the prevalence of ICU delirium in children less than 18 years old that underwent cardiac surgery within the last 30 days. The secondary aim of the study was to identify risk factors associated with ICU delirium in postoperative pediatric cardiac surgical patients., Design: A 1-day, multicenter point-prevalence study of delirium in pediatric postoperative cardiac surgery patients., Setting: Twenty-seven pediatric cardiac and general critical care units caring for postoperative pediatric cardiac surgery patients in North America., Patients: All children less than 18 years old hospitalized in the cardiac critical care units at 06:00 on a randomly selected, study day., Interventions: Eligible children were screened for delirium using the Cornell Assessment of Pediatric Delirium by the study team in collaboration with the bedside nurse., Measurement and Main Results: Overall, 181 patients were enrolled and 40% (n = 73) screened positive for delirium. There were no statistically significant differences in patient demographic information, severity of defect or surgical procedure, past medical history, or postoperative day between patients screening positive or negative for delirium. Our bivariate analysis found those patients screening positive had a longer duration of mechanical ventilation (12.8 vs 5.1 d; p = 0.02); required more vasoactive support (55% vs 26%; p = 0.0009); and had a higher number of invasive catheters (4 vs 3 catheters; p = 0.001). Delirium-positive patients received more total opioid exposure (1.80 vs 0.36 mg/kg/d of morphine equivalents; p < 0.001), did not have an ambulation or physical therapy schedule (p = 0.02), had not been out of bed in the previous 24 hours (p < 0.0002), and parents were not at the bedside at time of data collection (p = 0.008). In the mixed-effects logistic regression analysis of modifiable risk factors, the following variables were associated with a positive delirium screen: 1) pain score, per point increase (odds ratio, 1.3; 1.06-1.60); 2) total opioid exposure, per mg/kg/d increase (odds ratio, 1.35; 1.06-1.73); 3) SBS less than 0 (odds ratio, 4.01; 1.21-13.27); 4) pain medication or sedative administered in the previous 4 hours (odds ratio, 3.49; 1.32-9.28); 5) no progressive physical therapy or ambulation schedule in their medical record (odds ratio, 4.40; 1.41-13.68); and 6) parents not at bedside at time of data collection (odds ratio, 2.31; 1.01-5.31)., Conclusions: We found delirium to be a common problem after cardiac surgery with several important modifiable risk factors., Competing Interests: The authors have disclosed that they do not have any potential conflicts of interest., (Copyright © 2020 by the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies.)

Objective: The objective of the mapping project was to develop an expert derived map between the International Statistical Classification of Diseases and Related Health Problems (ICD) clinical modifications (CM) and the Abbreviated Injury Scale (AIS) to be able to relate AIS severity to ICD coded data road traffic collision data in EU datasets. The maps were developed to enable the identification of serious AIS3+ injury and provide details of the mapping process for assumptions to be made about injury severity from mass datasets. This article describes in detail the mapping process of the International Classification of Diseases Ninth Revision, Clinical Modification (ICD-9-CM) and the International Classification of Diseases Tenth Revision, Clinical Modification (ICD-10-CM) codes to the Abbreviated Injury Scale 2005, Update 2008 (AIS08) codes to identify injury with an AIS severity of 3 or more (AIS3+ severity) to determine 'serious' (MAIS3+) road traffic injuries. Methods: Over 19,000 ICD codes were mapped from the following injury categories; injury ICD-9-CM (Chapter 17) codes between '800 and 999.9' and injury ICD-10-CM (Chapter 19) 'S' and 'T' prefixed codes were reviewed and mapped to an AIS08 category and then relate the severity to three groups; AIS3+, AIS < =2 and AIS 9 (no-map). The mapping was undertaken by ICD coding experts and certified AIS specialists from Europe, North America, Australia and Canada in face-to-face working groups and subsequent webinars between May 2014 and October 2015. During the process, the business rules were documented to define guidelines for the mapping process and enable inter-rater discrepancies to be resolved. Results: In total 2,504 ICD-9-CM codes were mapped to the AIS, of which 780 (31%) were assigned an AIS3+ severity. For the16,508 ICD-10-CM mapped codes a total of 2,323 (14%) were assigned an AIS3+ severity. Some 17% (n = 426) and 27% (n = 4,485) of ICD-9-CM and ICD-10-CM codes respectively were assigned to AIS9 (no-map) following the mapping process. It was evident there were 'problem' codes that could not be easily mapped to an AIS code to reflect severity. Problem maps affect the specificity of the map and severity when used to translate historical data in large datasets. Conclusions: The Association for the Advancement in Automotive Medicine, AAAM-endorsed expert-derived map offers a unique tool to road safety researchers to establish the number of MAIS3+ serious injuries occurring on the roads. The detailed process offered in this paper will enable researchers to understand the decision making and identify limitations when using the AIS08/ICD map on country-specific data. The results could inform protocols for dealing with problem codes to enable country comparisons of MAIS3+ serious injury rates.

Securing environmental flows in support of freshwater biodiversity is an evolving field of practice. An example of a large-scale program dedicated to restoring environmental flows is the Columbia Basin Water Transactions Program in the Pacific Northwest region of North America, which has been restoring flows in dewatered tributary habitats for imperiled salmon species over the past decade. This paper discusses a four-tiered flow restoration accounting framework for tracking the implementation and impacts of water transactions as an effective tool for adaptive management. The flow restoration accounting framework provides compliance and flow accounting information to monitor transaction efficacy. We review the implementation of the flow restoration accounting framework monitoring framework to demonstrate (a) the extent of water transactions that have been implemented over the past decade, (b) the volumes of restored flow in meeting flow targets for restoring habitat for anadromous fish species, and (c) an example of aquatic habitat enhancement that resulted from Columbia Basin Water Transactions Program investments. Project results show that from 2002 to 2015, the Columbia Basin Water Transactions Program has completed more than 450 water rights transactions, restoring approximately 1.59 million megaliters to date, with an additional 10.98 million megaliters of flow protected for use over the next 100 years. This has resulted in the watering of over 2414 stream kilometers within the Columbia Basin. We conclude with a discussion of the insights gained through the implementation of the flow restoration accounting framework. Understanding the approach and efficacy of a monitoring framework applied across a large river basin can be informative to emerging flow-restoration and adaptive management efforts in areas of conservation concern.

Multiple genetically and antigenically distinct hemagglutinin genes of the H1 and H3 influenza A virus (IAV) subtypes co-circulate in North American swine. This diversity has evolved by repeated transmission of IAVs from humans to swine and subsequent antigenic drift in swine. To understand the evolutionary dynamics of these diverse HA lineages in North American swine, we undertook a phylogenetic analysis of 1576 H1 and 607 H3 HA gene segments, as well as 834 N1 and 1293 N2 NA gene segments, and 2126 M gene segments. These data revealed yearly co-circulation of H1N1, H1N2, and H3N2 viruses, with three HA clades representing the majority of the HA sequences: of the H1 viruses, 42% were classified as H1δ1 and 40.6% were classified as H1γ; and of the H3 viruses 53% were classified as cluster IV-A H3N2. We detected a genetically distinct minor clade consisting of 37 H1 viruses isolated between 2003 and 2013, which we classified as H1γ-2. We estimated that this clade circulated in swine since approximately 1995, but it was not detected in swine until 2003. Though this clade only represents 1.07% of swine H1 sequences reported over the past 10 years, hemagglutination inhibition (HI) assays demonstrated that representatives of this clade of viruses are antigenically distinct, and, when measured using antigenic cartography, were as many as 7 antigenic units from other H1γ viruses. Therefore vaccines against the contemporary H1γ viruses are not likely to cross-protect against γ-2 viruses. The long-term circulation of these γ-2 viruses suggests that minor populations of viruses may be underreported in the national dataset given the long branch lengths and gaps in detections. The identification of these γ-2 viruses demonstrates the need for robust surveillance to capture the full diversity IAVs in swine in the USA and the importance of antigenic drift in the diversification and emergence of new antigenic variants in swine, which complicates vaccine design., (Published by Elsevier B.V.)

The complex and unresolved evolutionary origins of the 2009 H1N1 influenza pandemic exposed major gaps in our knowledge of the global spatial ecology and evolution of influenza A viruses in swine (swIAVs). Here we undertake an expansive phylogenetic analysis of swIAV sequence data and demonstrate that the global live swine trade strongly predicts the spatial dissemination of swIAVs, with Europe and North America acting as sources of viruses in Asian countries. In contrast, China has the world's largest swine population but is not a major exporter of live swine, and is not an important source of swIAVs in neighbouring Asian countries or globally. A meta-population simulation model incorporating trade data predicts that the global ecology of swIAVs is more complex than previously thought, and the United States and China's large swine populations are unlikely to be representative of swIAV diversity in their respective geographic regions, requiring independent surveillance efforts throughout Latin America and Asia.

The geographic ranges of closely related species can vary dramatically, yet we do not fully grasp the mechanisms underlying such variation. The niche breadth hypothesis posits that species that have evolved broad environmental tolerances can achieve larger geographic ranges than species with narrow environmental tolerances. In turn, plasticity and genetic variation in ecologically important traits and adaptation to environmentally variable areas can facilitate the evolution of broad environmental tolerance. We used five pairs of western North American monkeyflowers to experimentally test these ideas by quantifying performance across eight temperature regimes. In four species pairs, species with broader thermal tolerances had larger geographic ranges, supporting the niche breadth hypothesis. As predicted, species with broader thermal tolerances also had more within-population genetic variation in thermal reaction norms and experienced greater thermal variation across their geographic ranges than species with narrow thermal tolerances. Species with narrow thermal tolerance may be particularly vulnerable to changing climatic conditions due to lack of plasticity and insufficient genetic variation to respond to novel selection pressures. Conversely, species experiencing high variation in temperature across their ranges may be buffered against extinction due to climatic changes because they have evolved tolerance to a broad range of temperatures., (© 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.)

The 2009 pandemic H1N1 infection in humans has been one of the greatest concerns for public health in recent years. However, influenza in pigs is a zoonotic viral disease well-known to virologists for almost one century with the classical H1N1 subtype the only responsible agent for swine influenza in the United States for many decades. Swine influenza was first recognized clinically in pigs in the Midwestern U.S. in 1918 and since that time it has remained important to the swine industry throughout the world. Since 1988, however, the epidemiology of swine influenza changed dramatically. A number of emerging subtypes and genotypes have become established in the U.S. swine population. The ability of multiple influenza virus lineages to infect pigs is associated with the emergence of reassortant viruses with new genomic arrangements, and the introduction of the 2009 pandemic H1N1 from humans to swine represents a well-known example. The recent epidemiological data regarding the current state of influenza A virus subtypes circulating in the Canadian and American swine population is discussed in this review.

Revealing the frequency and determinants of reassortment among RNA genome segments is fundamental to understanding basic aspects of the biology and evolution of the influenza virus. To estimate the extent of genomic reassortment in influenza viruses circulating in North American swine, we performed a phylogenetic analysis of 139 whole-genome viral sequences sampled during 1998-2011 and representing seven antigenically distinct viral lineages. The highest amounts of reassortment were detected between the H3 and the internal gene segments (PB2, PB1, PA, NP, M and NS), while the lowest reassortment frequencies were observed among the H1γ, H1pdm and neuraminidase segments, particularly N1. Less reassortment was observed among specific haemagglutinin-neuraminidase combinations that were more prevalent in swine, suggesting that some genome constellations may be evolutionarily more stable.

Determining how species' geographic ranges are governed by current climates and how they will respond to rapid climatic change poses a major biological challenge. Geographic ranges are often spatially fragmented and composed of genetically differentiated populations that are locally adapted to different thermal regimes. Tradeoffs between different aspects of thermal performance, such as between tolerance to high temperature and tolerance to low temperature or between maximal performance and breadth of performance, suggest that the performance of a given population will be a subset of that of the species. Therefore, species-level projections of distribution might overestimate the species' ability to persist at any given location. However, current approaches to modeling distributions often do not consider variation among populations. Here, we estimated genetically-based differences in thermal performance curves for growth among 12 populations of the scarlet monkeyflower, Mimulus cardinalis, a perennial herb of western North America. We inferred the maximum relative growth rate (RGR(max)), temperature optimum (T(opt)), and temperature breadth (T(breadth)) for each population. We used these data to test for tradeoffs in thermal performance, generate mechanistic population-level projections of distribution under current and future climates, and examine how variation in aspects of thermal performance influences forecasts of range shifts. Populations differed significantly in RGR(max) and had variable, but overlapping, estimates of T(opt) and T(breadth). T(opt) declined with latitude and increased with temperature of origin, consistent with tradeoffs between performances at low temperatures versus those at high temperatures. Further, T(breadth) was negatively related to RGR(max), as expected for a specialist-generalist tradeoff. Parameters of the thermal performance curve influenced properties of projected distributions. For both current and future climates, T(opt) was negatively related to latitudinal position, while T(breadth) was positively related to projected range size. The magnitude and direction of range shifts also varied with T(opt) and T(breadth), but sometimes in unexpected ways. For example, the fraction of habitat remaining suitable increased with T(opt) but decreased with T(breadth). Northern limits of all populations were projected to shift north, but the magnitude of shift decreased with T(opt) and increased with T(breadth). Median latitude was projected to shift north for populations with high T(breadth) and low T(opt), but south for populations with low T(breadth) and high T(opt). Distributions inferred by integrating population-level projections did not differ from a species-level projection that ignored variation among populations. However, the species-level approach masked the potential array of divergent responses by populations that might lead to genotypic sorting within the species' range. Thermal performance tradeoffs among populations within the species' range had important, but sometimes counterintuitive, effects on projected responses to climatic change., (© The Author 2011. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved.)

Background: A novel A/H1N1 was identified in the human population in North America in April 2009. The gene constellation of the virus was a combination from swine influenza A viruses (SIV) of North American and Eurasian lineages that had never before been identified in swine or other species., Objectives: The objectives were to (i) evaluate the clinical response of swine following experimental inoculation with pandemic H1N1 2009; (ii) assess serologic cross-reactivity between H1N1 2009 and contemporary SIV antisera; and (iii) develop a molecular assay to differentiate North American-lineage SIV from H1N1 2009., Methods: Experiment 1: Weaned pigs were experimentally infected with A/California/04/2009 (H1N1). Experiment 2: The cross-reactivity of a panel of US SIV H1N1 or H1N2 antisera with three isolates of pandemic A/H1N1 was evaluated. Experiment 3: A polymerase chain reaction (PCR)-based diagnostic test was developed and validated on samples from experimentally infected pigs., Results and Conclusions: In experiment 1, all inoculated pigs demonstrated clinical signs and lesions similar to those induced by endemic SIV. Viable virus and antigen were only detected in the respiratory tract. In experiment 2, serologic cross-reactivity was limited against H1N1 2009 isolates, notably among virus antisera from the same HA phylogenetic cluster. The limited cross-reactivity suggests North American pigs may not be fully protected against H1N1 2009 from previous exposure or vaccination and novel tests are needed to rapidly diagnose the introduction of H1N1 2009. In experiment 3, an RT-PCR test that discriminates between H1N1 2009 and endemic North American SIV was developed and validated on clinical samples.

Poplars (Populus spp.) comprise an important component of circumpolar boreal forest ecosystems and are the model species for tree genomics. In this study, we surveyed genetic variation and population differentiation in three nuclear genes among populations of balsam poplar (Populus balsamifera) in North America. We examined nucleotide sequence variation in alcohol dehydrogenase 1 (Adh1) and glyceraldehyde 3-phosphate dehydrogenase (G3pdh), two well-studied nuclear loci in plants, and abscisic acid insensitivity 1B (ABI1B), a locus coincident with timing of seasonal dormancy in quantitative trait locus (QTL) studies of hybrid poplars. We compared estimates of baseline population genetic parameters for these loci with those obtained in studies of other poplar species, particularly European aspen (Populus tremula). Average pairwise nucleotide diversity (pi(tot) = 0.00216-0.00353) was equivalent to that in Populus trichocarpa, but markedly less than that in P. tremula. Elevated levels of population structure were observed in ABI1B between the northern and southern regions (F(CT) = 0.184, P < 0.001) and among populations (F(ST) = 0.256, P < 0.001). These results suggest that geographic or taxonomic factors are important for understanding patterns of variation throughout the genus Populus. Our findings have the potential to aid in the design of sampling regimes for conservation and breeding stock and contribute to historical inferences regarding the factors that shaped the genetic diversity of boreal plant species.

Influenza is a zoonotic viral disease that represents a health and economic threat to both humans and animals worldwide. Swine influenza (SI) was first recognized clinically in pigs in the Midwestern U.S., in 1918, coinciding with the human influenza pandemic known as the Spanish flu. Since that time SI has remained of importance to the swine industry throughout the world. In this review, the epidemiology of swine influenza virus (SIV) infection in North American pigs is described in detail. The first 80 years of SI remained relatively static, whereas the last decade has become dynamic with the establishment of many emerging subtypes. With the increasing number of novel subtypes and genetic variants, the control of SI has become increasingly difficult and innovative strategies to combat this economically important zoonotic disease are critical. Therefore, protective immune responses against influenza virus infections as well as new paradigms of vaccine development in pigs are discussed in the review. It is expected that the dynamic evolutionary changes of SIVs in North American pigs will continue, making currently available prophylactic approaches of limited use to control the spread and economic losses associated with this important swine pathogen.