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Non‐union during healing of bone fractures affects up to ~5% of patients worldwide. Given the success of recombinant human platelet‐derived growth factor‐B chain homodimer (rhPDGF‐BB) in promoting angiogenesis and bone fusion in the hindfoot and ankle, rhPDGF‐BB combined with bovine type I collagen/β‐TCP matrix (AIBG) could serve as a viable alternative to autografts in the treatment of non‐unions. Defects (~2 mm gaps) were surgically induced in tibiae of skeletally mature New Zealand white rabbits. Animals were allocated to one of four groups—(1) negative control (empty defect, healing for 8 weeks), (2 and 3) acute treatment with AIBG (healing for 4 or 8 weeks), and (4) chronic treatment with AIBG (injection 4 weeks post defect creation and then healing for 8 weeks). Bone formation was analyzed qualitatively and semi‐quantitatively through histology. Samples were imaged using dual‐energy X‐ray absorptiometry and computed tomography for defect visualization and volumetric reconstruction, respectively. Delayed healing or non‐healing was observed in the negative control group, whereas defects treated with AIBG in an acute setting yielded bone formation as early as 4 weeks with bone growth appearing discontinuous. At 8 weeks (acute setting), substantial remodeling was observed with higher degrees of bone organization characterized by appositional bone growth. The chronic healing, experimental, group yielded bone formation and remodeling, with no indication of non‐union after treatment with AIBG. Furthermore, bone growth in the chronic healing group was accompanied by an increased presence of osteons, osteonal canals, and interstitial lamellae. Qualitatively and semiquantitatively, chronic application of AI facilitated complete bridging of the induced non‐union defects, while untreated defects or defects treated acutely with AIBG demonstrated a lack of complete bridging at 8 weeks. [ABSTRACT FROM AUTHOR]

Background Objectives Methods Results Conclusions The use of Mohs micrographic surgery (MMS) in melanoma treatment has divided opinion and evidence‐based guidelines are lacking.This systematic review aimed to analyse clinical outcomes for patients with invasive melanomas treated with Mohs rather than wide local excision (WLE).Embase, MEDLINE and Cochrane databases (to 30 August 2023) were searched for studies using Mohs to treat invasive melanoma. Outcomes of interest were local recurrence and death from melanoma.Thirty‐five articles involving 41,499 patients with invasive melanoma treated with Mohs were identified. Sixteen studies compared Mohs with WLE and 19 were Mohs‐only, non‐comparative studies. Patients treated with Mohs differed significantly from those undergoing WLE, in particular Mohs patients were older and had thinner melanomas. Two comparative studies using the same data source reported adjusted hazard ratios for melanoma‐specific death and both showed no significant difference between Mohs and WLE‐treated patients; 0.87 (95% CI 0.55–1.35) and 1.20 (95% CI 0.71–20.36). There was also no statistically significant difference in local recurrence risk; the unadjusted risk ratio for patients treated with Mohs was 0.46 (95% CI 0.14–1.51 p = 0.20) with moderate heterogeneity (I2 = 62%). No studies reported multivariable analyses for risk of local recurrence. Many studies generated from relatively few and often overlapping data sets have reported the use of Mohs to treat patients with invasive melanoma. Fewer studies were comparative between Mohs and WLE and these reported substantially different baseline risks of recurrence and death from melanoma between the groups. Mohs has generally been used for thinner melanomas in older patients; therefore, comparisons based on univariable analyses are likely to have been misleading.On the basis of currently available data, it is not possible to reliably assess whether outcomes differ if invasive melanomas with comparable features are treated with Mohs or WLE, and randomized trial evidence will be required for reliable conclusions to be reached. [ABSTRACT FROM AUTHOR]

During the early stages of limb and fin regeneration in aquatic vertebrates (i.e., fishes and amphibians), blastema undergo transcriptional rewiring of innate immune signaling pathways to promote immune cell recruitment. In mammals, a fundamental component of innate immune signaling is the cytosolic DNA sensing pathway, cGAS‐STING. However, to what extent the cGAS‐STING pathway influences regeneration in aquatic anamniotes is unknown. In jawed vertebrates, negative regulation of cGAS‐STING activity is accomplished by suppressors of cytosolic DNA such as Trex1, Pml, and PML‐like exon 9 (Plex9) exonucleases. Here, we examine the expression of these suppressors of cGAS‐STING, as well as inflammatory genes and cGAS activity during caudal fin and limb regeneration using the spotted gar (Lepisosteus oculatus) and axolotl (Ambystoma mexicanum) model species, and during age‐related senescence in zebrafish (Danio rerio). In the regenerative blastema of wounded gar and axolotl, we observe increased inflammatory gene expression, including interferon genes and interleukins 6 and 8. We also observed a decrease in axolotl Trex1 and gar pml expression during the early phases of wound healing which correlates with a dramatic increase in cGAS activity. In contrast, the plex9.1 gene does not change in expression during wound healing in gar. However, we observed decreased expression of plex9.1 in the senescing cardiac tissue of aged zebrafish, where 2′3′‐cGAMP levels are elevated. Finally, we demonstrate a similar pattern of Trex1, pml, and plex9.1 gene regulation across species in response to exogenous 2′3′‐cGAMP. Thus, during the early stages of limb‐fin regeneration, Pml, Trex1, and Plex9.1 exonucleases are downregulated, presumably to allow an evolutionarily ancient cGAS‐STING activity to promote inflammation and the recruitment of immune cells. Research highlights: The cGAS‐STING pathway is activated during anamniote tissue regeneration and aging.Suppressors of cGAS‐STING (Pml, Plex9.1, TREX1) are downregulated to promote cGAS activity.cGAMP regulates the expression of cGAS suppressors in aquatic vertebrates. [ABSTRACT FROM AUTHOR]

Objective: To determine the positivity rate of congenital cytomegalovirus (cCMV) testing among universal, hearing‐targeted CMV testing (HT‐cCMV) and delayed targeted dried blood spot (DBS) testing newborn screening programs, and to examine the characteristics of successful HT‐cCMV testing programs. Study Design: Prospective survey of birth hospitals performing early CMV testing. Setting: Multiple institutions. Methods: Birth hospitals participating in the National Institutes of Health ValEAR clinical trial were surveyed to determine the rates of cCMV positivity associated with 3 different testing approaches: universal testing, HT‐cCMV, and DBS testing. A mixed methods model was created to determine associations between successful HT‐cCMV screening and specific screening protocols. Results: Eighty‐two birth hospitals were surveyed from February 2019 to December 2021. Seven thousand six hundred seventy infants underwent universal screening, 9017 infants HT‐cCMV and 535 infants delayed DBS testing. The rates of cCMV positivity were 0.5%, 1.5%, and 7.3%, respectively. The positivity rate for universal CMV screening was less during the COVID‐19 pandemic than that reported prior to the pandemic. There were no statistically significant drops in positivity for any approach during the pandemic. For HT‐cCMV testing, unique order sets and rigorous posttesting protocols were associated with successful screening programs. Conclusion: Rates of cCMV positivity differed among the 3 approaches. The rates are comparable to cohort studies reported in the literature. Universal CMV prevalence decreased during the pandemic but not significantly. Institutions with specific order set for CMV testing where the primary care physician orders the test and the nurse facilitates the testing process exhibited higher rates of HT‐cCMV testing. [ABSTRACT FROM AUTHOR]

Background: Primary brain tumors (BTs) are rare, but cause morbidity and mortality disproportionately to their incidence. Prevalence estimates population‐level cancer burdens at a specified time. This study estimates the prevalence of malignant and non‐malignant BTs in comparison to other cancers. Methods: Incidence data were obtained from the Central Brain Tumor Registry of the United States (2000–2019, varying), a combined data set including the Center for Disease Control and Prevention's National Program of Cancer Registries and National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program. Incidence of non‐BT cancers were obtained from the United States Cancer Statistics (2001–2019). Incidence and survival estimates for all cancers were obtained from SEER (1975–2018). Complete prevalence as of December 31, 2019, was estimated using prevEst. Estimates were generated overall for non‐BT cancers, by BT histopathology, age groups at prevalence (0–14, 15–39, 40–64, 65+ years), and sex. Results: We estimated 1,323,121 individuals with a diagnosis of BTs at the date of prevalence. The majority of BT cases had non‐malignant tumors (85.3%). Among all cancers, BTs were the most prevalent cancer type among those ages 15 to 39 years, second among those ages 0 to 14 years, and in the top five among those ages 40 to 64 years. The plurality of prevalent cases (43.5%) occurred among those ages 65+ years. Overall, females had a higher prevalence of BTs than males, with an overall female:male prevalence ratio of 1.68. Conclusions: BTs contribute significantly to the cancer burden in the United States, particularly among those younger than age 65 years. Understanding complete prevalence is crucial for monitoring cancer burden to inform clinical research and public policy. We include a comparison of prevalence estimates for all primary brain tumors to other common cancers by age group in the United States. We also provide a description of the complete prevalence of primary malignant and nonmalignant brain and other central nervous system tumors in the United States for 2019, an update to a previous study. [ABSTRACT FROM AUTHOR]

Mobile species are particularly affected by artificial barriers requiring large investments to restore connectivity. However, few large‐scale, long‐term studies have investigated the ecological outcomes of restoring connectivity for these species. Our study, spanning 15–20 years, quantified response trajectories, which represent temporal trends following disturbance, of three native salmonids colonizing 20 km of protected habitat following restoration of fish passage at Landsburg Dam, Cedar River, WA, in 2003. Built in 1901, the dam blocked the upriver movement of native anadromous coho and Chinook salmon and nonanadromous mountain whitefish for 102 years. Restoration effectiveness was also assessed by comparing temporal trends in freshwater productivity of juvenile coho and Chinook salmon in the Cedar River after restoration to a nearby undammed subbasin. We also compared summer densities of juvenile coho and Chinook salmon, and mountain whitefish above the dam measured a decade after restoration to undammed reference systems. Anadromous salmon and nonanadromous mountain whitefish populations increased linearly or nonlinearly following restoration. The positive, asymptotic response represented by adult Chinook salmon counts indicates a slowing in population recovery rate, plateauing a decade after restoration. In contrast, annual abundance of adult coho salmon increased at a constant rate, indicating additional capacity 15 years post‐restoration. Salmonid compositional diversity, driven largely by juvenile coho salmon, also increased nonlinearly, plateauing in a decade. We observed substantial spatial variation in the temporal response, as juvenile coho salmon and mountain whitefish population expansion slowed linearly with upstream distance from the restoration site. There was evidence that some of the annual variation in salmonid biomass in summer was a result of discharge variability in winter and spring, with biomass declining as flow variability increased. Species reintroduction and establishment had no discernible effect on stream‐rearing salmonids living above the dam before restoration, while increasing coho freshwater productivity at the subbasin scale. Results from our study showed recolonization by three mobile species, each with a unique life history, takes at least a decade or more and was dependent on species and life stage, size of the spawning population, distance from restoration site, and annual variability in streamflow. [ABSTRACT FROM AUTHOR]

Brain and other central nervous system (CNS) tumors are among the most fatal cancers and account for substantial morbidity and mortality in the United States. Population‐based data from the Central Brain Tumor Registry of the United States (a combined data set of the National Program of Cancer Registries [NPCR] and Surveillance, Epidemiology, and End Results [SEER] registries), NPCR, National Vital Statistics System and SEER program were analyzed to assess the contemporary burden of malignant and nonmalignant brain and other CNS tumors (hereafter brain) by histology, anatomic site, age, sex, and race/ethnicity. Malignant brain tumor incidence rates declined by 0.8% annually from 2008 to 2017 for all ages combined but increased 0.5% to 0.7% per year among children and adolescents. Malignant brain tumor incidence is highest in males and non‐Hispanic White individuals, whereas the rates for nonmalignant tumors are highest in females and non‐Hispanic Black individuals. Five‐year relative survival for all malignant brain tumors combined increased between 1975 to 1977 and 2009 to 2015 from 23% to 36%, with larger gains among younger age groups. Less improvement among older age groups largely reflects a higher burden of glioblastoma, for which there have been few major advances in prevention, early detection, and treatment the past 4 decades. Specifically, 5‐year glioblastoma survival only increased from 4% to 7% during the same time period. In addition, important survival disparities by race/ethnicity remain for childhood tumors, with the largest Black‐White disparities for diffuse astrocytomas (75% vs 86% for patients diagnosed during 2009‐2015) and embryonal tumors (59% vs 67%). Increased resources for the collection and reporting of timely consistent data are critical for advancing research to elucidate the causes of sex, age, and racial/ethnic differences in brain tumor occurrence, especially for rarer subtypes and among understudied populations. [ABSTRACT FROM AUTHOR]

This document is a collection of references for articles related to the study of cardiac physiology and arrhythmias. The articles cover various topics, including calcium handling abnormalities in atrial fibrillation, the role of specific channels in atrial fibroblasts, the contribution of reactive oxygen species to the Frank-Starling mechanism, optical mapping of contracting hearts, and the role of specific channels in calcium-dependent triggered activity and cardiac arrhythmias. The articles provide valuable insights into the mechanisms and potential treatments for different cardiac conditions. The authors of the articles are funded by various organizations, including the German Cardiac Society, the Canadian Institutes of Health Research, and the Heart and Stroke Foundation of Canada. [Extracted from the article]

Coral records of surface‐ocean conditions extend our knowledge of interannual El Niño–Southern Oscillation (ENSO) variability into the preinstrumental period. That said, the wide range of natural variability within the climate system as well as multiple sources of uncertainties inherent to the coral archive produce challenges for the paleoclimate community to detect forced changes in ENSO using coral geochemical records. We present a new coral proxy system model (PSM) of intermediate complexity, geared toward the evaluation of changes in interannual variance. Our coral PSM adds additional layers of complexity to previously published transfer functions of sensor models that describe how the archive responds to sea surface temperature (SST) and salinity. We use SST and salinity output from the Community Earth System Model Last Millennium Ensemble 850 control to model coral oxygen isotopic ratios and SST derived from Sr/Ca. We present a detailed analysis of our PSM using climate model output for sites in the central and southwest Pacific before extending the analyses to span the broader tropical Pacific. We demonstrate how variable growth rates, analytical and calibration errors, and age model assumptions systematically impact estimates of interannual variance and show that the relative magnitude of the change in interannual variance is location dependent. Importantly, however, we find that even with the added uncertainties in our PSM, corals from many circum‐Pacific locations are broadly able to capture decadal and longer (decadal+) changes in ENSO variability. Our code is publicly available on GitHub to facilitate future comparisons between model output and coral proxy data. Plain Language Summary: Climate scientists use the chemistry of coral skeletons to study past tropical climate conditions. The elemental ratio of strontium to calcium (Sr/Ca) and the oxygen isotopic composition (δ18O) in the coral skeleton are used to reconstruct past sea surface temperature and salinity. Coral Sr/Ca varies in response to changes in sea surface temperature, whereas coral δ18O records both changes in temperature and salinity. Individual corals provide tens to hundreds of years of climate information from the tropical oceans. They are well‐suited for studying variability related to the El Niño–Southern Oscillation (ENSO), a climate phenomenon that impacts global temperature and rainfall patterns every few years. We rely on both climate proxy data and simulations from global climate models to study changes in ENSO variability in the past. Nevertheless, it is difficult to directly compare proxy data with climate model output due to the imperfect nature of how the climate signal is recorded in the coral skeleton. Proxy system models are a tool designed to help bridge the gap between climate information recorded in corals and climate model output. In this study, we develop a coral proxy system model to demonstrate how different processes impact a coral's ability to record changes in ENSO variability. Key Points: We present a new coral proxy system model to facilitate comparison between proxy observations and climate model outputAnalytical and calibration errors, variable growth rates, and age modeling uncertainties all have measurable impacts on interannual varianceThe relative importance of different uncertainties on interannual variance are site dependent [ABSTRACT FROM AUTHOR]

Glioma incidence is highest in non‐Hispanic Whites, and to date, glioma genome‐wide association studies (GWAS) to date have only included European ancestry (EA) populations. African Americans and Hispanics in the US have varying proportions of EA, African (AA) and Native American ancestries (NAA). It is unknown if identified GWAS loci or increased EA is associated with increased glioma risk. We assessed whether EA was associated with glioma in African Americans and Hispanics. Data were obtained for 832 cases and 675 controls from the Glioma International Case–Control Study and GliomaSE Case–Control Study previously estimated to have <80% EA, or self‐identify as non‐White. We estimated global and local ancestry using fastStructure and RFMix, respectively, using 1,000 genomes project reference populations. Within groups with ≥40% AA (AFR≥0.4), and ≥15% NAA (AMR≥0.15), genome‐wide association between local EA and glioma was evaluated using logistic regression conditioned on global EA for all gliomas. We identified two regions (7q21.11, p = 6.36 × 10−4; 11p11.12, p = 7.0 × 10−4) associated with increased EA, and one associated with decreased EA (20p12.13, p = 0.0026) in AFR≥0.4. In addition, we identified a peak at rs1620291 (p = 4.36 × 10−6) in 7q21.3. Among AMR≥0.15, we found an association between increased EA in one region (12q24.21, p = 8.38 × 10−4), and decreased EA in two regions (8q24.21, p = 0. 0010; 20q13.33, p = 6.36 × 10−4). No other significant associations were identified. This analysis identified an association between glioma and two regions previously identified in EA populations (8q24.21, 20q13.33) and four novel regions (7q21.11, 11p11.12, 12q24.21 and 20p12.13). The identifications of novel association with EA suggest regions to target for future genetic association studies. What's new? Glioma is rare in non‐White populations, and most glioma genome‐wide association studies have included only primarily European ancestry populations. Here, the authors assess whether variation in European ancestry is associated with glioma risk in populations with a combination of European, African and Native American ancestry. Based on African American and Hispanic cases from two large glioma case–control studies, this analysis shows that increased European ancestry in admixed populations may be associated with increased glioma risk. The associations between glioma and two chromosomal regions previously identified in European ancestry populations, and four novel regions, may guide future studies. [ABSTRACT FROM AUTHOR]

Background: Multiple studies have reported higher rates of glioma in areas with higher socioeconomic status (SES) but to the authors' knowledge have not stratified by other factors, including race/ethnicity or urban versus rural location.Methods: The authors identified the average annual age-adjusted incidence rates and calculated hazard ratios for death for gliomas of various subtypes, stratified by a county-level index for SES, race/ethnicity, US region, and rural versus urban status.Results: Rates of glioma were highest in counties with higher SES (rate ratio, 1.18; 95% CI, 1.15-1.22 comparing the highest with the lowest quintiles [P < .001]). Stratified by race/ethnicity, higher rates in high SES counties persisted for white non-Hispanic individuals. Stratified by rural versus urban status, differences in incidence by SES were more pronounced among urban counties. Survival was higher for residents of high SES counties after adjustment for age and extent of surgical resection (hazard ratio, 0.82; 95% CI, 0.76-0.87 comparing the highest with the lowest quintile of SES [P < .001]). Survival was higher among white Hispanic, black, and Asian/Pacific Islander individuals compared with white non-Hispanic individuals, after adjustment for age, SES, and extent of surgical resection, and when restricted to those individuals with glioblastoma who received radiation and chemotherapy.Conclusions: The incidence of glioma was higher in US counties of high compared with low SES. These differences were most pronounced among white non-Hispanic individuals and white Hispanic individuals residing in urban areas. Better survival was observed in high SES counties, even when adjusting for extent of surgical resection, and when restricted to those who received radiation and chemotherapy for glioblastoma. Differences in incidence and survival were associated with SES and race, rather than rural versus urban status. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most common malignant brain tumor in the United States. Incidence of GBM increases with age, and younger age‐at‐diagnosis is significantly associated with improved prognosis. While the relationship between candidate GBM risk SNPs and age‐at‐diagnosis has been explored, genome‐wide association studies (GWAS) have not previously been stratified by age. Potential age‐specific genetic effects were assessed in autosomal SNPs for GBM patients using data from four previous GWAS. Using age distribution tertiles (18–53, 54–64, 65+) datasets were analyzed using age‐stratified logistic regression to generate p values, odds ratios (OR), and 95% confidence intervals (95%CI), and then combined using meta‐analysis. There were 4,512 total GBM cases, and 10,582 controls used for analysis. Significant associations were detected at two previously identified SNPs in 7p11.2 (rs723527 [p54–63 = 1.50x10−9, OR54–63 = 1.28, 95%CI54–63 = 1.18–1.39; p64+ = 2.14x10−11, OR64+ = 1.32, 95%CI64+ = 1.21–1.43] and rs11979158 [p54–63 = 6.13x10−8, OR54–63 = 1.35, 95%CI54–63 = 1.21–1.50; p64+ = 2.18x10−10, OR64+ = 1.42, 95%CI64+ = 1.27–1.58]) but only in persons >54. There was also a significant association at the previously identified lower grade glioma (LGG) risk locus at 8q24.21 (rs55705857) in persons ages 18–53 (p18–53 = 9.30 × 10−11, OR18–53 = 1.76, 95%CI18–53 = 1.49–2.10). Within The Cancer Genome Atlas (TCGA) there was higher prevalence of 'LGG'‐like tumor characteristics in GBM samples in those 18–53, with IDH1/2 mutation frequency of 15%, as compared to 2.1% [54–63] and 0.8% [64+] (p = 0.0005). Age‐specific differences in cancer susceptibility can provide important clues to etiology. The association of a SNP known to confer risk for IDH1/2 mutant glioma and higher prevalence of IDH1/2 mutation within younger individuals 18–53 suggests that more younger individuals may present initially with 'secondary glioblastoma.' What's new? The authors performed the first genome‐wide association analysis examining age‐at‐diagnosis and germline risk variants in glioblastoma. They report a higher frequency of germline variants associated with lower grade gliomas (LGG) in the younger cohort (age 18–53), as well as high frequency of LGG‐like somatic variants in The Cancer Genome Atlas Glioblastoma cohort. This could indicate that glioblastoma at a younger age might more often evolve from an LGG (secondary glioblastoma) than at an older age and should be taken into consideration when molecular classification is not available. [ABSTRACT FROM AUTHOR]

Abstract: Essentially no information is known about the behavior of individual molecular catalysts under reaction conditions. This is a result of the averaging inherent to traditional analytical techniques. Herein, a combined fluorescence microscopy and 1H NMR spectroscopy study reveals that unique (that is, non‐ensemble averaged) distributions and time‐variable kinetics from molecular ruthenium catalysts within growing polynorbornene occur and are detectable between 10−9  m and 10−6  m of substrate, surprisingly just 1000‐fold less concentrated than a typical laboratory bench‐scale reaction. The kinetic states governing single‐turnover events are determinable by overlay of the signal arising from individual monomer insertion reactions with that from polymer growth from neighboring catalysts. [ABSTRACT FROM AUTHOR]

Abstract: Background: Accurate cancer survival statistics are necessary for describing population‐level survival patterns and measuring advancements in cancer care. Net cancer survival is measured using two methods: cause‐specific survival (CSS) and relative survival (RS). Both are valid methodologies for estimating net survival and are used widely in medical research. In these analyses, we compare CSS to RS at selected cancer sites. Methods: Using data from 18 SEER registries between 2000 and 2014, five‐year RS and CSS estimates were generated overall as well as by age groups and by sex. To assess how closely the two survival methods corresponded, net survival percent difference was calculated with the following formula: ((RS‐CSS)/RS)*100. Results: Discrepancies between estimates obtained from CSS and RS methods varied with cancer site and age, but not by sex. In most cases, CSS was greater than RS, but cancers with available early screening and high survival rate had higher RS than CSS. Net survival percent differences were small in children and adolescents and young adults, and large in adults over the age of 40. Conclusions: While both CSS and RS aim to quantify net survival, the estimates tend to differ due to the biases present in both methodologies. Error when estimating CSS most frequently stems from misclassification of cause of death, whereas RS is subject to error when no suitable life tables are available. Appropriate use of CSS and RS requires a detailed understanding of the characteristics of the disease that may lead to differences in the estimates generated by these methods. [ABSTRACT FROM AUTHOR]

Background: Obesity and chronic pain are prevalent concerns. Pain is frequently experienced in weight-bearing joints, but is common in other areas of the body as well, suggesting other factors. Poor diet often contributes to obesity and can directly influence the immune system. We have shown that poor diet prolongs recovery from inflammatory injury. Therefore, our goal was to determine whether poor-quality diet-induced consequences could be prevented or reversed by an anti-inflammatory diet (AID).Methods: A Standard American Diet (SAD) was developed to investigate the effects of poor diet on pain. The SAD includes amounts of refined sugar, carbohydrates and fats that better model the typical American diet, as compared to high-fat diets. We developed an AID to explore whether the effects of the SAD could reverse or whether the AID would enhance recovery prophylactically. The AID was developed using ingredients (epigallocatechin gallate, sulforaphane, resveratrol, curcumin and ginseng) with known anti-inflammatory properties. Following 15 weeks of diet [SAD, AID or regular (REG)] exposure, male and female mice underwent inflammatory injury, at which point some animals had their diets switched for the remainder of the study.Results: Animals who consumed the SAD showed longer recovery compared to the AID- and REG-fed animals. Animals switched off the SAD had faster recovery times, with AID-fed animals recovering as fast as REG-fed animals.Conclusions: Poor diet prolonged recovery from inflammatory injury. Substitution of SAD with AID or REG promoted faster recovery. These findings suggest diet can be used as a non-pharmacological intervention following injury.Significance: Obesity may increase susceptibility to chronic pain often due to poor diet. Diet has potential to be used as treatment for pain. This study investigates the use of a novel translatable diet to act as a preventative (i.e. prior to surgery) or an intervention (i.e. following an injury). [ABSTRACT FROM AUTHOR]

Abstract: Catalytic cycles are typically depicted as possessing time‐invariant steps with fixed rates. Yet the true behavior of individual catalysts with respect to time is unknown, hidden by the ensemble averaging inherent to bulk measurements. Evidence is presented for variable chemical kinetics at individual catalysts, with a focus on ring‐opening metathesis polymerization catalyzed by the second‐generation Grubbs’ ruthenium catalyst. Fluorescence microscopy is used to probe the chemical kinetics of the reaction because the technique possesses sufficient sensitivity for the detection of single chemical reactions. Insertion reactions in submicron regions likely occur at groups of many (not single) catalysts, yet not so many that their unique kinetic behavior is ensemble averaged. [ABSTRACT FROM AUTHOR]

Multiple active individual molecular ruthenium catalysts have been pinpointed within growing polynorbornene, thereby revealing information on the reaction dynamics and location that is unavailable through traditional ensemble experiments. This is the first single-turnover imaging of a molecular catalyst by fluorescence microscopy and allows detection of individual monomer reactions at an industrially important molecular ruthenium ring-opening metathesis polymerization (ROMP) catalyst under synthetically relevant conditions (e.g. unmodified industrial catalyst, ambient pressure, condensed phase, ca. 0.03 m monomer). These results further establish the key fundamentals of this imaging technique for characterizing the reactivity and location of active molecular catalysts even when they are the minor components. [ABSTRACT FROM AUTHOR]

Background and purpose Small vessel disease (SVD) and Alzheimer's disease (AD) are two common causes of cognitive impairment and dementia, traditionally considered as distinct processes. The relationship between radiological features suggestive of AD and SVD was explored, and the association of each of these features with cognitive status at 1 year was investigated in patients with stroke or transient ischaemic attack. Methods Anonymized data were accessed from the Virtual International Stroke Trials Archive (VISTA). Medial temporal lobe atrophy (MTA; a marker of AD) and markers of SVD were rated using validated ordinal visual scales. Cognitive status was evaluated with the Mini Mental State Examination (MMSE) 1 year after the index stroke. Logistic regression models were used to investigate independent associations between (i) baseline SVD features and MTA and (ii) all baseline neuroimaging features and cognitive status 1 year post-stroke. Results In all, 234 patients were included, mean (±SD) age 65.7 ± 13.1 years, 145 (62%) male. Moderate to severe MTA was present in 104 (44%) patients. SVD features were independently associated with MTA ( P < 0.001). After adjusting for age, sex, disability after stroke, hypertension and diabetes mellitus, MTA was the only radiological feature independently associated with cognitive impairment, defined using thresholds of MMSE ≤ 26 (odds ratio 1.94; 95% confidence interval 1.28-2.94) and MMSE ≤ 23 (odds ratio 2.31; 95% confidence interval 1.48-3.62). Conclusion In patients with ischaemic cerebrovascular disease, SVD features are associated with MTA, which is a common finding in stroke survivors. SVD and AD type neurodegeneration coexist, but the AD marker MTA, rather than SVD markers, is associated with post-stroke cognitive impairment. [ABSTRACT FROM AUTHOR]

While Pacific salmon are known for their extensive marine migrations, some species display much more limited alternative patterns, including residence within interior marine waters. To more clearly define the scale of movement of these residents, we used acoustic telemetry to track subadult Chinook Salmon Oncorhynchus tshawytscha caught in and released from discrete areas of the Salish Sea. Their movements were determined from detections at fixed receivers in central Puget Sound, Admiralty Inlet, the San Juan Islands, and the Strait of Juan de Fuca. Cluster analysis of the detections indicated four groups, with much less commonality of movement than might be inferred from the proximity of the tagging locations, which were only tens of kilometers apart. For example, none of the salmon tagged in central Puget Sound were detected in the San Juan Islands and vice versa. Thus, Chinook Salmon occupying central Puget Sound and the San Juan Islands may exhibit different distributions, extents of movement, and degrees of basin fidelity. These results provide information relevant to the management and conservation of this species, which is listed as threatened under the U.S. Endangered Species Act, and whose movements cross the U.S.–Canadian boundary. These findings may also help explain the variation in organic contaminant levels among Puget Sound‐origin Chinook Salmon. [ABSTRACT FROM AUTHOR]

Stream simulation has become an increasingly common culvert design method around the world. It is based on the assumption that geologic and hydraulic conditions in natural channels define passage characteristics for migrating fish and that water crossing structures that imitate these conditions can then achieve those same passage characteristics. This study expands on an initial evaluation of 19 culverts in 2003 to 50 culverts and includes methods and analyses comparing hydraulic characteristics based on cross sections, profile variation, and bed texture between each culvert and its paired reference reach situated in an adjacent section of the natural channel of each stream. Taken as a group, these culverts simulate bed texture, 100-year recurrence interval flood velocity and 2-year flood width but did not simulate thalweg complexity or other hydraulic metrics. Culvert span, relative to the bankfull width of the stream, does not by itself determine whether the culvert simulates the reference reach. Of the 50 culverts, many of which experienced record floods, only one showed significant bed degradation. [ABSTRACT FROM AUTHOR]

Sampling in Iliamna Lake, Alaska, U.S.A. revealed that a greater proportion of coastrange sculpins Cottus aleuticus were infected by the cestode Schistocephalus solidus than slimy sculpins Cottus cognatus (52 v. 23%), and infected C. aleuticus contained more cestodes than did C. cognatus (2·1 v. 1·3 per fish). Consumption of sockeye salmon Oncorhynchus nerka eggs (the primary diet item) was lower in fishes with cestodes, and a model based on cestode prevalence and age composition estimated higher rates of infection and parasite-associated mortality in C. aleuticus compared with C. cognatus. [ABSTRACT FROM AUTHOR]

Incidence and survival rates are commonly reported statistics, but these may fail to capture the full impact of childhood cancers. We describe the years of potential life lost ( YPLL) and years of life lived with disease ( YLLD) in children and adolescents who died of cancer in the United States to estimate the impact of childhood cancer in the United States in 2009. We examined mortality data in 2009 among children and adolescents <20 years old in both the National Vital Statistics System ( NVSS) and the Surveillance, Epidemiology, and End Results ( SEER) datasets. YPLL and YLLD were calculated for all deaths due to cancer. Histology-specific YPLL and YLLD of central nervous system ( CNS) tumors, leukemia, and lymphoma were estimated using SEER. There were 2233 deaths and 153,390.4 YPLL due to neoplasm in 2009. CNS tumors were the largest cause of YPLL (31%) among deaths due to cancer and were the cause of 1.4% of YPLL due to all causes. For specific histologies, the greatest mean YPLL per death was due to atypical teratoid/rhabdoid tumor (78.0 years lost). The histology with the highest mean YLLD per death in children and adolescents who died of cancer was primitive neuroectodermal tumor (4.6 years lived). CNS tumors are the most common solid malignancy in individuals <20 years old and have the highest YPLL cost of all cancers. This offers the first histology-specific description of YPLL in children and adolescents and proposes a new measure of cancer impact, YLLD, in individuals who die of their disease. YPLL and YLLD complement traditional indicators of mortality and help place CNS tumors in the context of other childhood malignancies. [ABSTRACT FROM AUTHOR]

The close relationship between stroke and dementia is an important health issue. Ischaemic stroke can facilitate the onset of vascular dementia as well as aggravate pre-existing cognitive decline. The onset of cognitive decline may become manifest immediately following the onset of ischaemic stroke, but often there is a delay in the development of cognitive decline after a stroke. This delay can be seen as a therapeutic time window allowing interventions to be applied to preserve cognition following stroke. Both neurodegenerative and vascular mechanisms are activated and probably result in overlapping processes within the neurovascular unit. This review focuses on the incidence and prevalence of cognitive decline following stroke, predisposing stroke aetiologies, pre-stroke decline, imaging factors and biomarkers. Outcomes are discussed in relation to timing of assessment and neuropsychological tests used for evaluation of cognitive decline in ischaemic stroke patients. Including such tests in routine evaluations of stroke patients after some weeks or months is recommended. Finally, an outlook on ongoing and planned intervention trials is added and some recommendations for future research are proposed. [ABSTRACT FROM AUTHOR]

BACKGROUND Time trends in cancer incidence rates (IR) are important to measure the changing burden of cancer on a population over time. The overall IR of cancer in the United States is declining. Although central nervous system tumors (CNST) are rare, they contribute disproportionately to mortality and morbidity. In this analysis, the authors examined trends in the incidence of the most common cancers and CNST between 2000 and 2010. METHODS The current analysis used data from the United States Cancer Statistics publication and the Central Brain Tumor Registry of the United States. Age-adjusted IR per 100,000 population with 95% confidence intervals and the annual percent change (APC) with 95% confidence intervals were calculated for selected common cancers and CNST overall and by age, sex, race/ethnicity, selected histologies, and malignancy status. RESULTS In adults, there were significant decreases in colon (2000-2010: APC, −3.1), breast (2000-2010: APC, −0.8), lung (2000-2010: APC, −1.1), and prostate (2000-2010: APC, −2.4) cancer as well as malignant CNST (2008-2010: APC, −3.1), but a significant increase was noted in nonmalignant CNST (2004-2010: APC, 2.7). In adolescents, there were significant increases in malignant CNST (2000-2008: APC, 1.0) and nonmalignant CNST (2004-2010: APC, 3.9). In children, there were significant increases in acute lymphocytic leukemia (2000-2010: APC, 1.0), non-Hodgkin lymphoma (2000-2010: APC, 0.6), and malignant CNST (2000-2010: APC, 0.6). CONCLUSIONS Surveillance of IR trends is an important way to measure the changing public health and economic burden of cancer. In the current study, there were significant decreases noted in the incidence of adult cancer, whereas adolescent and childhood cancer IR were either stable or increasing. Cancer 2015;121:102-112. © 2014 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. [ABSTRACT FROM AUTHOR]

This study employed a combination of otolith microchemistry to indicate the recent habitat use, and plasma concentrations of the hormone insulin-like growth factor 1 ( IGF1) as an index of recent growth rate, to demonstrate differences in growth and habitat use by Dolly Varden Salvelinus malma occupying both freshwater and estuarine habitats in south-west Alaska. Extensive sampling in all habitats revealed that fish had higher IGF1 levels in estuarine compared to lake habitats throughout the summer, and that the growth rates in different habitats within the estuary varied seasonally. In addition, otolith microchemistry indicated differentiation in estuarine habitat use among individual S. malma throughout summer months. Although growth in the estuary was higher than in fresh water in nearly all sites and months, the benefits and use of the estuarine habitats varied on finer spatial scales. Therefore, this study further illustrates the diverse life histories of S. malma and indicates an evaluation of the benefits of marine waters needs to include sub-estuary scale habitat use. [ABSTRACT FROM AUTHOR]

The process of salmon colonization in the upper Cedar River and Rock Creek, Washington, following the installation of a fish ladder at Landsburg Diversion Dam in 2003, offered an opportunity to measure the effects of interspecific interactions on the dynamics of resident fish populations. Rapid recolonization by Coho SalmonOncorhynchus kisutchprovided a natural experiment to determine the influence of Coho Salmon densities on the growth, movement, and survival of resident Coastal Cutthroat TroutO. clarkii clarkiirelative to other abiotic and biotic factors such as habitat quality, environmental conditions, and conspecific density. During 14 seasonal sampling events from 2005 to 2009, we PIT-tagged 1,851 and recaptured 394 Cutthroat Trout in Rock Creek, collected habitat data, enumerated fish populations, and monitored fish movements with PIT tag antenna arrays. Trout growth varied significantly among seasons and was greatest during spring and early summer. Mean juvenile Coho Salmon density in summer and fall increased eightfold from 0.04 to 0.32 and from 0.08 to 0.68 fish/m2, respectively, approaching levels seen in established populations, but did not explain variation in trout growth, movement, or survival. Summer growth of trout parr and fry were both negatively correlated with the density of conspecifics but were positively correlated with total salmonid density. Additionally, trout parr growth was positively correlated with stream discharge, whereas trout fry growth was negatively correlated with initial size and declined during the course of the study. However, abiotic and biotic explanatory variables accounted for little of the variation in trout growth, movement, and survival, suggesting that a great deal of individual variation exists. Overall, trout were largely unaffected by Coho Salmon colonists despite large increases in juvenile Coho Salmon density, though this may change if salmon populations continue to grow. Received October 18, 2013; accepted May 5, 2014 [ABSTRACT FROM AUTHOR]

Wild, downstream-migrating cutthroat trout, Oncorhynchus clarkii clarkii, smolts and adults were captured at a weir in Big Beef Creek, Hood Canal, Washington, surgically implanted with acoustic tags and tracked to identify spring and summer movements using stationary receivers in order to test the assumption that the species moves little while in marine waters. Overall, 93-96% migrated from the stream into the east side of the long narrow fjord, where they dispersed north and south along the shoreline. Most O. c. clarkii were detected nearshore within 10 km of the release site, with declining detection rates to 77 km. Over one-third (36%) crossed c. 2-4 km of deep water to the other side but only one O. c. clarkii left the Hood Canal basin. Movements and behaviour patterns did not differ between smolts and adults but cluster analysis revealed two modes of distribution, here categorized as residents and migrants. Within these categories of overall distribution, a range of finer-scale behaviour patterns was observed, including sedentary individuals, daily moving between proximate sites and more continuous long-distance travel. Diel movement patterns varied markedly among individuals but overall activity increased near dawn, peaked around mid-day and declined but continued at night. These patterns contrast with sympatric and closely related steelhead trout, Oncorhynchus mykiss, providing new insights into the diversity of salmonid behaviour. [ABSTRACT FROM AUTHOR]

Native Coastal Cutthroat Trout Oncorhynchus clarkii clarkii and Coastal Steelhead O. mykiss irideus hybridize naturally in watersheds of the Pacific Northwest yet maintain species integrity. Partial reproductive isolation due to differences in spawning habitat may limit hybridization between these species, but this process is poorly understood. We used a riverscape approach to determine the spatial distribution of spawning habitats used by native Coastal Cutthroat Trout and Steelhead as evidenced by the distribution of recently emerged fry. Molecular genetic markers were used to classify individuals as pure species or hybrids, and individuals were assigned to age-classes based on length. Fish and physical habitat data were collected in a spatially continuous framework to assess the relationship between habitat and watershed features and the spatial distribution of parental species and hybrids. Sampling occurred in 35 reaches from tidewaters to headwaters in a small (20 km²) coastal watershed in Washington State. Cutthroat, Steelhead, and hybrid trout accounted for 35%, 42%, and 23% of the fish collected, respectively. Strong segregation of spawning areas between Coastal Cutthroat Trout and Steelhead was evidenced by the distribution of age-0 trout. Cutthroat Trout were located farther upstream and in smaller tributaries than Steelhead were. The best predictor of species occurrence at a site was the drainage area of the watershed that contributed to the site. This area was positively correlated with the occurrence of age-0 Steelhead and negatively with the presence of Cutthroat Trout, whereas hybrids were found in areas occupied by both parental species. A similar pattern was observed in older juveniles of both species but overlap was greater, suggesting substantial dispersal of trout after emergence. Our results offer support for spatial reproductive segregation as a factor limiting hybridization between Steelhead and Coastal Cutthroat Trout. [ABSTRACT FROM AUTHOR]

Inbreeding is of concern in supportive breeding programmes in Pacific salmonids, Oncorhynchus spp, where the number of breeding adults is limited by rearing space or poor survival to adulthood, and large numbers are released to supplement wild stocks and fisheries. We reconstructed the pedigree of 6602 migratory hatchery steelhead ( Oncorhynchus mykiss) over four generations, to determine the incidence and fitness consequences of inbreeding in a northwest USA programme. The hatchery maintained an effective population size [ABSTRACT FROM AUTHOR]

Morphological, dietary and life-history variation in Arctic charr Salvelinus alpinus were characterized from three geographically proximate, but isolated lakes and one large lake into which they drain in south-western Alaska. Polymorphism was predicted to occur in the first three lakes because S. alpinus tend to become polymorphic in deep, isolated lakes with few co-occurring species. Only one morph was evident in the large lake and two of the three isolated lakes. In the third isolated lake, Lower Tazimina Lake, small and large morphs were found, the latter including two forms differing in growth rate. The small morph additionally differed from the two large forms by having more gill rakers and a deeper body than same-sized individuals of the large morph, consuming more limnetic and fewer benthic resources, having a greater gonado-somatic index and maturing at a smaller size. The two large forms consumed only slightly different foods (more terrestrial insects were consumed by the medium-growth form; more snails by the high-growth form). Trends in consumption of resources with body shape also differed between lakes. Variability in life history of S. alpinus in these Alaskan lakes was as broad as that found elsewhere. This variability is important for understanding lake ecosystems of remote regions where this species is commonly dominant. [ABSTRACT FROM AUTHOR]

Systems biology, the approach that combines reduction and integration to explore dynamic structure-function interrelations across biomedically relevant spatio-temporal scales, is applied to heart research. [ABSTRACT FROM AUTHOR]

Understanding the factors influencing the success of juvenile Pacific salmon Oncorhynchus spp. in newly colonized habitats is essential to their recovery in large areas across the West Coast of the United States and Canada. We studied biotic and abiotic factors associated with survival during the early stages of colonization and population establishment of juvenile coho salmon O. kisutch in Rock Creek, a tributary of the upper Cedar River in the Lake Washington basin of Puget Sound, Washington. The stream was occupied by resident fishes (e.g., rainbow trout O. mykiss, cutthroat trout O. clarkii, speckled dace Rhinichthys osculus, and several sculpins Cottus spp.), but adult coho salmon and other anadromous fishes had been excluded by a dam from 1901 until fish ladder installation in 2003. We defined logistic regression models and used an information-theoretic approach to predict apparent survival with various combinations of individual fish condition, location competition, and local habitat quality. The best-approximating models included measures of brood year, body size, habitat, and migration timing. Survival was positively associated with body size and habitat quality and negatively associated with competition. Survival from late summer to smolt migration varied among years (mean ± SD = 27 ± 11%) and was significantly higher within Rock Creek (73 ± 11%) than during seaward migration in the Cedar River and Lake Washington (38 ± 14%). Juvenile coho salmon established a population and outnumbered resident salmonid species by 40% in the lower 2 km of Rock Creek within 5 years of colonization. Overall, the results revealed the linkage between the colonization success of juvenile coho salmon and the biotic features and habitat quality in a newly accessible environment during the stream-rearing phase of their life history. [ABSTRACT FROM AUTHOR]

The LF-at-age trajectories differentiated two populations of Dolly Varden charr Salvelinus malma and a population of Arctic charr Salvelinus alpinus from the eastern end of Iliamna Lake, Alaska. Salvelinus malma from the Pedro Bay ponds were the smallest for a given age, followed by Salvelinus alpinus from the lake, and S. malma from the Iliamna River were much larger. The utilization of a large sockeye salmon Oncorhynchus nerka subsidy by the three Salvelinus spp. populations was then investigated by comparing diet data and mixing model (MixSIR) outputs based on carbon and nitrogen stable isotopes. Stomach contents indicated that both S. malma populations fed on O. nerka products, especially eggs and larval Diptera that had scavenged O. nerka carcasses, whereas S. alpinus fed on a variety of prey items such as three-spined sticklebacks Gasterosteus aculeatus and snails. Stable-isotope analysis corroborated the diet data; the two S. malma populations incorporated more O. nerka-derived nutrients into their tissues than did S. alpinus from the lake, although all populations showed substantial utilization of O. nerka-derived resources. Salvelinus alpinus also seemed to be much more omnivorous, as shown by stable-isotope mixing models, than the S. malma populations. The dramatic differences in growth rate between the two S. malma populations, despite similar trophic patterns, indicate that other important genetic or environmental factors affect their life history, including proximate temperature controls and ultimate predation pressures. [ABSTRACT FROM AUTHOR]

Time series on juvenile life-history traits obtained from sockeye salmon Oncorhynchus nerka were analysed to assess lake-specific environmental influences on juvenile migration timing, size and survival of fish from a common gene pool. Every year for the past two decades, O. nerka have been spawned at a hatchery facility, and the progeny released into two lakes that differ in average summer temperatures, limnological attributes and growth opportunities. Juveniles reared in the warmer, more productive Crosswind Lake were larger and heavier as smolts compared to those from the cooler, less productive Summit Lake and had higher in-lake and subsequent marine survival. Crosswind Lake smolts migrated from the lake to sea slightly earlier in the season but the migration timing distributions overlapped considerably across years. Fry stocking density had a negative effect on smolt length for both lakes, and a negative effect on in-lake survival in Summit Lake. Taken together, the results revealed a strong effect of lake-rearing environment on the expression of life-history variation in O. nerka. The stocking of these lakes each year with juveniles from a single mixed-source population provided a large-scale reverse common-garden experiment, where the same gene pool was exposed to different environments, rather than the different gene pools in the same environment approach typical of evolutionary ecology studies. Other researchers are encouraged to seek and exploit similar serendipitous situations, which might allow environmental and genetic influences on ecologically important traits to be distinguished in natural or semi-natural settings. [ABSTRACT FROM AUTHOR]

In just over a decade, Systems Biology has moved from being an idea, or rather a disparate set of ideas, to a mainstream feature of research and funding priorities. Institutes, departments, and centers of various flavors of Systems Biology have sprung up all over the world. An Internet search now produces more than 2 million hits. Of the 2,800 entries in PubMed with “Systems Biology” in either the title or the abstract, only two papers were published before 2000, and >90% were published in the past five years. In this article, we interpret Systems Biology as an approach rather than as a field or a destination of research. We illustrate that this approach is productive for the exploration of systems behavior, or “phenotypes,” at all levels of structural and functional complexity, explicitly including the supracellular domain, and suggest how this may be related conceptually to genomes and biochemical networks. We discuss the role of models in Systems Biology and conclude with a consideration of their utility in biomedical research and development. [ABSTRACT FROM AUTHOR]

Selection during the colonization of new habitat is critical to the process of local adaptation, but has rarely been studied. We measured the form, direction, and strength of selection on body size and date of arrival to the breeding grounds over the first three cohorts (2003–2005) of a coho salmon ( Oncorhynchus kisutch) population colonizing 33 km of habitat made accessible by modification of Landsburg Diversion Dam, on the Cedar River, Washington, USA. Salmon were sampled as they bypassed the dam, parentage was assigned based on genotypes from 10 microsatellite loci, and standardized selection gradients were calculated using the number of returning adult offspring as the fitness metric. Larger fish in both sexes produced more adult offspring, and the magnitude of the effect increased in subsequent years for males, suggesting that low densities attenuated traditional size-biased intrasexual competition. For both sexes, directional selection favoured early breeders in 2003, but stabilizing selection on breeding date was observed in 2004 and 2005. Adults that arrived, and presumably bred, early produced stream-rearing juvenile offspring that were larger at a common date than offspring from later parents, providing a possible mechanism linking breeding date to offspring viability. Comparison to studies employing similar methodology indicated selection during colonization was strong, particularly with respect to reproductive timing. Finally, female mean reproductive success exceeded that needed for replacement in all years so the population expanded in the first generation, demonstrating that salmon can proficiently exploit vacant habitat. [ABSTRACT FROM AUTHOR]

Knowledge of temporal segregation in migration timing among populations is critical for management of fisheries that exploit a complex of populations with an overlap in timing. We examined the potential for fishery selection on populations of sockeye salmon in the Wood River system, Bristol Bay, Alaska, by determining the relationship between migration timing (hence, vulnerability to fishing) and the population of origin and breeding date. We assessed migration patterns among populations with a multiyear mark-recapture study testing the hypotheses that the timing of upriver migration varies systematically with respect to spawning habitat, lake of origin, and spawning population. The results revealed organization in migration timing through the Wood River among populations spawning in the streams, beaches, and rivers of the system. The primary source of variation in migration timing among populations was spawning habitat and, to a lesser extent, the lake of origin. Stream-spawning populations migrated before river-spawning populations, consistent with the earlier spawning in streams than in rivers. However, beach-spawning populations were among the earliest to migrate, yet they spawned as late as river spawners. A likelihood model revealed that spawn timing was not tightly coupled with migration timing by populations through the Wood River, and there was broad overlap in migration timing among spawning populations. Results also revealed a link between migration timing and arrival on spawning grounds within a population that was intensively sampled, indicating that early upriver migrants also tended to enter the spawning grounds before later-migrating individuals. Fisheries that are selective with respect to timing can have strong effects on the phenotypic and genotypic diversity of the populations under such pressure, and the phenomenon of temporally biased fisheries merits further investigation. [ABSTRACT FROM AUTHOR]

Hatcheries produce Pacific salmon and trout spp. for many purposes, including fishery enhancement. The genetic integrity of wild populations spawning near such hatcheries may depend on the efficacy of their spatial or temporal separation from hatchery fish. We describe a simple, novel approach based on the examination of scales from an iteroparous species, steelhead , to evaluate whether the ratio of hatchery-produced adults to wild adults on the spawning grounds met recommended levels. In this river, migrating steelhead are diverted into the hatchery by a weir. Hatchery-produced fish are manually spawned and killed in the hatchery, whereas wild fish are passed over the weir and allowed to spawn naturally upstream from the hatchery. Therefore, in principle, all hatchery-produced adults should be captured at the hatchery on their first spawning migration. However, scales from 8.3% (58 of 699) of female and 2.6% (22 of 844) of male hatchery-produced steelhead adults showed evidence of previous spawning migrations. Although this frequency was lower than the incidence of repeat spawning by wild fish (males, 11.0%; females, 20.3%), these records nevertheless indicated significant reproductive opportunities in the wild for hatchery-produced fish. Combining these frequencies of repeat spawning with estimates of the survival and numbers of wild fish, we modeled the ratio of hatchery to wild fish on the spawning grounds using data from eight return years. This ratio exceeded the recommended levels under all reasonable scenarios modeled (14.7-89.6% hatchery fish). Combined with evidence of spatial and temporal overlap, our data suggest that unless changes are made to increase the capture efficiency of adults at Washington State's Forks Creek Hatchery and similar hatcheries relying on segregated stocks, the risks of genetic introgression and ecological interactions with wild steelhead populations will remain high. [ABSTRACT FROM AUTHOR]

Levels of differentiation in morphological traits (age at maturity, body length at age, egg mass and body depth) and spawning time were examined in sockeye salmon Oncorhynchus nerka from three geographically proximate but physically distinct creeks in Lake Aleknagik, Alaska. Happy Creek fish had significantly greater values for most measured morphological traits, and Eagle Creek fish spawned significantly later than fish in the other creeks. Phenotypic differentiation between creeks, measured as PST, was then compared with microsatellite marker differentiation between creeks, measured as FST. No correlations were apparent between PST and FST values, and PST values were generally significantly larger than zero ( PST= 0·0018–0·31) whereas FST values were not ( FST=−0·0004 to 0·0016). The insignificant pair-wise FST values between creek samples indicated that gene flow occurs between creeks, assuming the creek populations have reached migration–drift equilibrium. However, the strong homing behaviour of sockeye salmon precludes a scenario in which fish from the three creeks constitute a single population that segregates by body size. Rather, significant phenotypic differentiation suggests that strong divergent selection occurs on the phenotypic traits despite the homogenizing effects of gene flow. [ABSTRACT FROM AUTHOR]

In some populations the phenomenon of partial migration develops where some individuals stay in a given habitat rather than move with the migratory component. Depending on the selective pressures, the individuals that stay may be larger, smaller or similar in size to those that move. Freshwater movements of juvenile sockeye salmon ( Oncorhynchus nerka Walbaum) fry vary among and within populations, and can be complex, especially in interconnected lake systems. We examined variation of movement patterns by a sockeye salmon population in an interconnected lake system during a period of rapid natural habitat change and found that fry migrating downstream were shorter, had lower body condition, and were more likely ill and moribund compared with fish remaining in the lake. However, otolith microstructure measurements indicated that emigrants did not grow significantly slower than residents prior to downstream movement. We show that patterns (i.e., demography of migrants, timing of movement) of downstream movement have changed since the 1970s, corresponding to changes in rearing habitat. Our findings parallel the results with other salmonid species and are generally consistent with the paradigm that density-dependent interactions from declining habitat availability or quality result in the downstream movement of competitively inferior individuals, although the mechanisms governing downstream migration are unclear in this system. [ABSTRACT FROM AUTHOR]

Salmon life histories are finely tuned to local environmental conditions, which are intimately linked to climate. We summarize the likely impacts of climate change on the physical environment of salmon in the Pacific Northwest and discuss the potential evolutionary consequences of these changes, with particular reference to Columbia River Basin spring/summer Chinook ( Oncorhynchus tshawytscha) and sockeye ( Oncorhynchus nerka) salmon. We discuss the possible evolutionary responses in migration and spawning date egg and juvenile growth and development rates, thermal tolerance, and disease resistance. We know little about ocean migration pathways, so cannot confidently suggest the potential changes in this life stage. Climate change might produce conflicting selection pressures in different life stages, which will interact with plastic (i.e. nongenetic) changes in various ways. To clarify these interactions, we present a conceptual model of how changing environmental conditions shift phenotypic optima and, through plastic responses, phenotype distributions, affecting the force of selection. Our predictions are tentative because we lack data on the strength of selection, heritability, and ecological and genetic linkages among many of the traits discussed here. Despite the challenges involved in experimental manipulation of species with complex life histories, such research is essential for full appreciation of the biological effects of climate change. [ABSTRACT FROM AUTHOR]

The Lake Washington watershed in Washington State has several discreet breeding populations of sockeye salmon Oncorhynchus nerka that return over the course of several months and remain in the lake for up to 6 months before spawning. Depending on the arrival timing and distribution of sockeye salmon in the lake, in-lake fisheries might disproportionately exploit one population or another and might select individuals from within populations having traits that covary with arrival timing (e.g., age, size, and sex). We applied disk tags to adult sockeye salmon as they entered the lake in 2003 and 2004 and tracked individual fish with ultrasonic transmitters. Recovery rates of disk-tagged fish declined over the course of both seasons and were lower in 2004 than in 2003, suggesting that prespawning mortality was occurring because of high water temperatures. Arrival timing did not vary consistently between populations and was at most weakly correlated with life history traits (older fish tended to arrive earlier). Ultrasonic transmitters revealed that individual sockeye salmon were distributed throughout the lake in the early summer but gradually congregated near the mouth of their natal stream in the fall. Fisheries are therefore likely to exploit the populations in proportion to their overall abundance without selecting strongly for spawning date or life history traits, tending to minimize evolutionary effects within populations. However, the expansion of a hatchery on the river with the largest population has been proposed; if fisheries increase to take advantage of the enhanced population, they may have a disproportionate effect on the smaller wild populations in other tributaries. [ABSTRACT FROM AUTHOR]

We investigated material models for a polymeric scaffold used for bone. The material was made by co‐extruding poly(ε‐caprolactone) (PCL), a biodegradable polyester, and poly(ethylene oxide) (PEO). The water soluble PEO was removed resulting in a porous scaffold. The stress–strain curve in compression was fit with a phenomenological model in hyperbolic form. This material model will be useful for designers for quasi‐static analysis as it provides a simple form that can easily be used in finite element models. The ASTM D‐1621 standard recommends using a secant modulus based on 10% strain. The resulting modulus has a smaller scatter in its value compared with the coefficients of the hyperbolic model, and it is therefore easier to compare differences in material processing and ensure quality of the scaffold. A prediction of the small–strain elastic modulus was constructed from images of the microstructure. Each pixel of the micrographs was represented with a brick finite element and assigned the Young's modulus of bulk PCL or a value of 0 for a pore. A compressive strain was imposed on the model and the resulting stresses were calculated. The elastic constants of the scaffold were then computed with Hooke's law for a linear‐elastic isotropic material. The model was able to predict the small–strain elastic modulus measured in the experiments to within one standard deviation. Thus, by knowing the microstructure of the scaffold, its bulk properties can be predicted from the material properties of the constituents. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006 [ABSTRACT FROM AUTHOR]

Here we critically review the scale and extent of adaptive genetic variation in Atlantic salmon ( Salmo salar L.), an important model system in evolutionary and conservation biology that provides fundamental insights into population persistence, adaptive response and the effects of anthropogenic change. We consider the process of adaptation as the end product of natural selection, one that can best be viewed as the degree of matching between phenotype and environment. We recognise three potential sources of adaptive variation: heritable variation in phenotypic traits related to fitness, variation at the molecular level in genes influenced by selection, and variation in the way genes interact with the environment to produce phenotypes of varying plasticity. Of all phenotypic traits examined, variation in body size (or in correlated characters such as growth rates, age of seaward migration or age at sexual maturity) generally shows the highest heritability, as well as a strong effect on fitness. Thus, body size in Atlantic salmon tends to be positively correlated with freshwater and marine survival, as well as with fecundity, egg size, reproductive success, and offspring survival. By contrast, the fitness implications of variation in behavioural traits such as aggression, sheltering behaviour, or timing of migration are largely unkown. The adaptive significance of molecular variation in salmonids is also scant and largely circumstantial, despite extensive molecular screening on these species. Adaptive variation can result in local adaptations (LA) when, among other necessary conditions, populations live in patchy environments, exchange few or no migrants, and are subjected to differential selective pressures. Evidence for LA in Atlantic salmon is indirect and comes mostly from ecological correlates in fitness-related traits, the failure of many translocations, the poor performance of domesticated stocks, results of a few common-garden experiments (where different populations were raised in a common environment in an attempt to dissociate heritable from environmentally induced phenotypic variation), and the pattern of inherited resistance to some parasites and diseases. Genotype × environment interactions occurr for many fitness traits, suggesting that LA might be important. However, the scale and extent of adaptive variation remains poorly understood and probably varies, depending on habitat heterogeneity, environmental stability and the relative roles of selection and drift. As maladaptation often results from phenotype-environment mismatch, we argue that acting as if populations are not locally adapted carries a much greater risk of mismanagement than acting under the assumption for local adaptations when there are none. As such, an evolutionary approach to salmon conservation is required, aimed at maintaining the conditions necessary for natural selection to operate most efficiently and unhindered. This may require minimising alterations to native genotypes and habitats to which populations have likely become adapted, but also allowing for population size to reach or extend beyond carrying capacity to encourage competition and other sources of natural mortality. [ABSTRACT FROM AUTHOR]

Reproductive tactics, aggression and courtship by large and small (jack) male sockeye salmon Oncorhynchus nerka with ripe females in temporary enclosures depended on the size and behaviour of the competitor, not the size of the focal male. When paired with other jacks or with large but less aggressive males, jacks fought for access to ripe females rather than sneaking, but used sneaking tactics when paired with large, aggressive males. Dominant males of both size groups courted actively and females spawned readily with all combinations of males. [ABSTRACT FROM AUTHOR]

Assignment tests are increasingly applied in ecology and conservation, although empirical comparisons of methods are still rare or are restricted to few of the available approaches. Furthermore, the performance of assignment tests in cases with low population differentiation, violations of Hardy–Weinberg equilibrium and unbalanced sampling designs has not been verified. The release of adult hatchery steelhead to spawn in Forks Creek in 1996 and 1997 provided an opportunity to compare the power of different assignment methods to distinguish their offspring from those of sympatric wild steelhead. We compared standard assignment methods requiring baseline samples (frequency, distance and Bayesian) and clustering approaches with and without baseline information, using six freely available computer programs. Assignments were verified by parentage data obtained for a subset of returning offspring. All methods provided similar assignment success, despite low differentiation between wild and hatchery fish ( FST = 0.02). Bayesian approaches with baseline data performed best, whereas the results of clustering methods were variable and depended on the samples included in the analysis and the availability of baseline information. Removal of a locus with null alleles and equalizing sample sizes had little effect on assignments. Our results demonstrate the robustness of most assignment tests to low differentiation and violations of assumptions, as well as their utility for ecological studies that require correct classification of different groups. [ABSTRACT FROM AUTHOR]

Pacific salmon develop many sexually dimorphic features at maturity, and the extent of development varies among populations. In this study, we compared a suite of traits including body length, body depth, jaw length, tooth size and skin mass in male and female sockeye salmon breeding in beach and creek habitats. Both tooth size and skin mass varied positively with body length. Within each of the breeding habitats, males had longer teeth than females, and within each sex, beach spawners had longer teeth than creek spawners. Males also had heavier skin than females in each habitat but, unlike the case with tooth size, creek spawners showed a much stronger relationship between skin mass and body length than did beach spawners. Tooth length was positively related to jaw length and skin mass among individuals within a given sex and habitat. Taken together, these results suggested that variation in tooth size parallels variation in other sexually dimorphic traits. Males and beach spawners tend to exhibit large trait values relative to females and creek spawners, and ‘well-endowed’ individuals displayed high values of all traits rather than a trade-off as might occur if investment in one trait compromised investment in others. However, the finding that creek fish tended to have thicker skin for a given body length than did beach fish suggested that factors other than merely defense against conspecifics during battle, such as abrasion and desiccation resistance in small streams, may influence the evolution of skin mass in mature sockeye salmon. [ABSTRACT FROM AUTHOR]