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Canada’s access to neutron beams for neutron scattering was significantly curtailed in 2018 with the closure of the National Research Universal (NRU) reactor in Chalk River, Ontario, Canada. New sources are needed for the long-term; otherwise, access will only become harder as the global supply shrinks. Compact Accelerator-based Neutron Sources (CANS) offer the possibility of an intense source of neutrons with a capital cost significantly lower than spallation sources. In this paper, we propose a CANS for Canada. The proposal is staged with the first stage offering a medium neutron flux, linear accelerator-based approach for neutron scattering that is also coupled with a boron neutron capture therapy (BNCT) station and a positron emission tomography (PET) isotope production station. The first stage will serve as a prototype for a second stage: a higher brightness, higher cost facility that could be viewed as a national centre for neutron applications.

Meningeal worm, or Parelaphostrongylus tenuis (P. tenuis) is a nematode parasite that can invade the nervous system of small ruminant and camelid species such as alpaca, llama, goats and sheep. Limited reports exist on the epidemiology of disease caused by the nematode in susceptible livestock. We examined archived necropsy reports from small ruminant and camelid mortalities that were submitted, post mortem, to the University of Minnesota Veterinary Diagnostic Laboratory (MNVDL) during 2001–2019 for gross necropsy, histopathology, and pathogen screening. We estimated P. tenuis-induced mortality over time and developed temporal models to better understand patterns and drivers of P. tenuis-induced mortalities in these animals. During the period under examination, 5,617 goats, sheep, llamas and alpacas were necropsied, revealing an overall P. tenuis-induced mortality rate of 1.14% in the necropsy submission pool for these species. P. tenuis-induced mortality rates were highest in llamas (9.91%) and alpacas (5.33%) compared to sheep and goats (P. tenuis-induced mortalities exhibited one seasonal peak, around October to December. P. tenuis-induced mortality rates varied greatly between years, and have significantly increased over time. We also observed a positive correlation between summer temperature (range 20.4–22.4°C) and P. tenuis-induced mortality rates (range 0–3.9%), but not precipitation. This study demonstrates seasonal patterns and differences in mortality between alpacas, goats, llamas and sheep and helps us to better understand the epidemiology of P. tenuis mortality.

A new ISOL rare isotope beam production facility, ARIEL, is under construction at TRIUMF. ARIEL aims at increasing the delivery of radioactive beams three fold with respect to the present capability of the ISAC facility. Part of ARIEL is the new CANREB equipment that can be described by the two main functionalities: a charge breeding system that includes RFQ cooler, EBIS and Nier separator, and a high-resolution mass separator system. The latter is designed to achieve a resolving power of twenty thousand for a transmitted emittance of three micrometer. The separator optics has been designed with symmetry in order to minimize high-order aberrations. The dispersion of the system is created by two identical ninety degree magnetic dipoles with a field flatness of one part in one hundred thousand. The dipoles are tested and the magnetic field characterized before being installed on line for operation. High-order aberrations can also be corrected by an electrostatic multipole; this features a novel design as well as a new tuning technique. In this paper we will present the latest results from the field characterization and discuss the high level application to tune the multipole.

Goats browsing in woodlands, whether for livestock production goals or vegetation management (e.g., targeted grazing to control invasive plants), are at risk of meningeal worm (Parelaphostrongylus tenuis) infection. Indeed, up to 25% incidence has been observed in goats employed in vegetation management. Infection, which occurs via the consumption of an infected gastropod intermediate host, is potentially deadly in goats. We experimentally tested whether co-grazing with waterfowl could reduce goats' exposure via waterfowl consumption of gastropods. Gastropods were sampled in a deciduous woodland before and after the addition of goats alone, goats and waterfowl, or a control with no animal addition. We found that goats browsing on their own increased the abundance of P. tenuis intermediate hosts; however, when goats co-grazed with waterfowl, these increases were not observed. Importantly, waterfowl did not significantly affect overall gastropod abundance, richness, or diversity. Thus, waterfowl co-grazing may effectively reduce goat contact with infectious gastropods without detrimentally affecting the gastropod community. While co-grazing goats with waterfowl may decrease their P. tenuis exposure risk, additional research is needed to confirm whether waterfowl can actually lower P. tenuis incidence.

STUDY QUESTION Can preimplantation genetic testing for aneuploidy (PGT-A) improve the live birth rate in patients with recurrent pregnancy loss (RPL)? SUMMARY ANSWER PGT-A use was associated with improved live birth rates in couples with recurrent pregnancy loss undergoing frozen embryo transfer (IVF-FET). WHAT IS KNOWN ALREADY Euploid embryo transfer is thought to optimize outcomes in some couples with infertility. There is insufficient evidence, however, supporting this approach to management of recurrent pregnancy loss. STUDY DESIGN, SIZE, DURATION This study included data collected by the Society of Assisted Reproductive Technologies Clinical Outcomes Reporting System (SART-CORS) for IVF-FET cycles between years 2010 through 2016. A total of 12 631 FET cycles in 10 060 couples were included in this analysis designed to assess the utility of PGT-A in couples with RPL undergoing FET, including 4287 cycles in couples with tubal disease who formed a control group. PARTICIPANTS/MATERIALS, SETTING, METHODS The experimental group included couples with RPL (strictly defined as a history of 3 or more pregnancy losses) undergoing FET with or without PGT-A. The primary outcome was live birth rate. Secondary outcomes included rates of clinical pregnancy, spontaneous abortion, and biochemical pregnancy loss. Differences were analyzed using generalized estimating equations logistic regression models to account for multiple cycles per patient. Covariates included in the model were age, gravidity, geographic region, race/ethnicity, smoking history, and indication for assisted reproductive technologies. Analyses were stratified for age groups as defined by SART: 42 years. MAIN RESULTS AND THE ROLE OF CHANCE In women with a diagnosis of RPL, the adjusted odds ratio (OR) comparing IVF-FET with PGT-A versus without PGT-A for live birth outcome was 1.31 (95% CI: 1.12, 1.52) for age 42 years. For clinical pregnancy, the OR was 1.26 (95% CI: 1.08, 1.48) for age 42 years. Finally, for spontaneous abortion, the OR was 0.95 (95% CI: 0.74, 1.21) for age 42 years. LIMITATIONS, REASONS FOR CAUTION The retrospective collection of data including only women with recurrent pregnancy loss undergoing FET presents a limitation of this study, and results may not be generalizable to all couples with recurrent pregnancy loss. Also, data regarding evaluation and treatment for RPL for the included women is unavailable. WIDER IMPLICATIONS OF THE FINDINGS This is the largest study to date assessing the utility of PGT-A in women with RPL. PGT-A was associated with improvement in live birth and clinical pregnancy in women with RPL, with the largest difference noted in the group of women with age greater than 42 years. Couples with RPL warrant counseling on all management options to reduce subsequent miscarriage, which may include IVF with PGT-A for euploid embryo selection. STUDY FUNDING/COMPETING INTEREST(S) There are no conflicts of interest to declare. TRIAL REGISTRATION NUMBER N/A.

Plants and animals host many microbial symbionts, including both pathogens and mutualists. However, most experimental studies include only one symbiont, and few examine interactions of more than two microbes with their host. Here, we examined whether coinfection with two pathogens causes a synergistic reduction in the benefits that hosts receive from a microbial mutualist. We also measured the effects of a microbial mutualist on the within- and between-host competition between coinfecting pathogens. We manipulated the presence of Clover yellow vein virus (ClYVV), Bean common mosaic virus (BCMV), rhizobia bacteria, and nitrogen fertilizer in common beans (Phaseolus vulgaris). We found asymmetric, context-dependent interactions among the three microbial symbionts and their host. Coinfection with both viruses led to greater than additive negative effects on the amount of nitrogen that plants received from rhizobia. Rhizobia colonization decreased immune signaling in singly infected plants, but not in coinfected plants. Compared to single ClYVV infection, ClYVV reached higher concentrations within hosts coinfected with BCMV, but only in the presence of rhizobia. Coinfection increased BCMV vertical transmission rates for plants without supplemental nitrogen, but overall vertical transmission opportunities were not affected due to reduced seed production. Examining interactions between multiple microbes sharing a host can reveal important insights about nutrient cycling, disease severity, and pathogen epidemiology.

Legumes are used in crop rotations by both large-scale and smallholder farmers alike to increase soil fertility, especially before high-nitrogen-demanding crops such as corn (maize). Legume crop residues and green manures are rich in nitrogen due to mutualistic rhizobia, bacteria that live in their roots and convert atmospheric nitrogen into a biologically available form. Growers can obtain recommendations from local extension offices about how much less inorganic nitrogen fertilizer needs to be added to a subsequent crop following different legume break crops for the predominant soil type (the nitrogen fertilizer replacement value, or NFRV). Due to the intimate relationship between legumes and rhizobia, conditions that affect plant health can also affect the rhizobia and how much nitrogen they provide. We use a combination of empirical data and previously published values to estimate reductions in nitrogen inputs under outbreaks of plant viruses of varying severity. We also use historical fertilizer prices to examine the economic impacts of this lost fertilizer for farmers. We find that fertilizer losses are greatest for crops that fix large amounts of nitrogen, such as clover and alfalfa as opposed to common bean. The economic impact on farmers is controlled by the proportion of plants with viral infections and the price of synthetic fertilizer. In a year of high disease prevalence, attention is normally focused on the yield of the diseased crops. We suggest that farmers growing legumes as break crops should be concerned about yields of subsequent crops as well. Viral diseases can be difficult to diagnose in the field, so the easiest way for farmers to prevent unexpected yield losses in subsequent crops is to test their soil when it is feasible to do so.

12 pags., 16 figs., 2 tabs., Background: Neutron-rich nuclei around neutron number N=60 show a dramatic shape transition from spherical ground states to prolate deformation in Sr98 and heavier nuclei. Purpose: The purpose of this study is to investigate the single-particle structure approaching the shape transitional region. Method: The level structures of neutron-rich Sr93,94,95 were studied via the H2(Sr94,95,96,t) one-neutron stripping reactions at TRIUMF using a beam energy of 5.5 AMeV. γ-rays emitted from excited states and recoiling charged particles were detected by using the TIGRESS and SHARC arrays, respectively. States were identified by gating on the excitation energy and, if possible, the coincident γ radiation.Results: Triton angular distributions for the reactions populating states in ejectile nuclei Sr93,94,95 were compared with distorted wave Born approximation calculations to assign and revise spin and parity quantum numbers and extract spectroscopic factors. The results were compared with shell-model calculations and the reverse (d,p) reactions and good agreement was obtained. Conclusions: The results for the H2(Sr94,t)Sr93 and H2(Sr95,t)Sr94 reactions are in good agreement with shell-model calculations. A two-level mixing analysis for the 0+ states in Sr94 suggest strong mixing of two shapes. For the H2(Sr96,t)Sr95 reaction the agreement with the shell-model is less good. The configuration of the ground state of Sr96 is already more complex than predicted, and therefore indications for the shape transition can already be observed before N=60., We acknowledge support from the Science and Technologies Facility Council (UK, Grants No. EP/D060575/1 and No. ST/L005727/1), the National Science Foundation (US, Grant No. PHY-1306297), the Natural Sciences and Engineering Research Council of Canada, the Canada Foundation for Innovation and the British Columbia Knowledge and Development Fund. TRIUMF receives federal funding via a contribution through the National Research Council Canada. K.W. acknowledges the support from the Spanish Ministerio de Economía, Industria y Competitividad, Gobierno de España RYC-2017-22007.

Background: The region around neutron number N=60 in the neutron-rich Sr and Zr nuclei is one of the most dramatic examples of a ground-state shape transition from (near) spherical below N=60 to strongly deformed shapes in the heavier isotopes. Purpose: The single-particle structure of Sr95-97 approaching the ground-state shape transition at Sr98 has been investigated via single-neutron transfer reactions using the (d,p) reaction in inverse kinematics. These reactions selectively populate states with a large overlap of the projectile ground state coupled to a neutron in a single-particle orbital. Method: Radioactive Sr94,95,96 nuclei with energies of 5.5 AMeV were used to bombard a CD2, where D denotes H2, target. Recoiling light charged particles and γ rays were detected using a quasi-4π silicon strip detector array and a 12-element Ge array. The excitation energy of states populated was reconstructed employing the missing mass method combined with γ-ray tagging and differential cross sections for final states were extracted. Results: A reaction model analysis of the angular distributions allowed for firm spin assignments to be made for the low-lying 352, 556, and 681 keV excited states in Sr95 and a constraint has been placed on the spin of the higher-lying 1666 keV state. Angular distributions have been extracted for ten states populated in the H2(Sr95,p)Sr96 reaction, and constraints have been provided for the spins and parities of several final states. Additionally, the 0, 167, and 522 keV states in Sr97 were populated through the H2(Sr96,p) reaction. Spectroscopic factors for all three reactions were extracted. Conclusions: Results are compared to shell-model calculations in several model spaces and the structure of low-lying states in Sr94 and Sr95 is well described. The spectroscopic strength of the 0+ and 2+ states in Sr96 is significantly more fragmented than predicted. The spectroscopic factors for the H2(Sr96,p)Sr97 reaction suggest that the two lowest-lying excited states have significant overlap with the weakly deformed ground state of Sr96, but the ground state of Sr97 has a different structure.

As part of its new Advanced Rare IsotopE Laboratory (ARIEL), TRIUMF is designing a novel High Resolution Separator (HRS) (Maloney et al., 2015) to separate rare isotopes. The HRS has a 180° bend, separated into two 90° magnetic dipoles, bend radius 1.2 m, with an electrostatic multipole corrector between them. Second order correction comes mainly from the dipole edge curvatures, but is intended to be fine-tuned with a sextupole component and a small octupole component in the multipole. This combination is designed to achieve 1:20,000 resolution for a 3 μm (horizontal) and 6 μm (vertical) emittance. A design for the HRS dipole magnets achieves both radial and integral flatness goals of −5 . A review of the optical design for the HRS is presented, including the study of limiting factors affecting separation, matching and aberration correction. Field simulations from the OPERA-3D (OPERA) [2] models of the dipole magnets are used in COSY Infinity (COSY) (Berz and Makino, 2005) [3] to find and optimize the transfer maps to 3rd order and study residual nonlinearities to 8th order.

Maternal spiral arteries and newly formed decidual capillaries support embryonic development prior to placentation. Previous studies demonstrated that Notch signaling is active in endothelial cells of both decidual capillaries and spiral arteries, however the role of Notch signaling in physiologic decidual angiogenesis and maintenance of the decidual vasculature in early mouse pregnancy has not yet been fully elucidated. We used the Cdh5-CreERT2, Jagged1(Jag1)flox/flox (Jag1∆EC) mouse model to delete Notch ligand, Jag1, in maternal endothelial cells during post-implantation, pre-placentation mouse pregnancy. Loss of endothelial Jag1 leads to increased expression of Notch effectors, Hey2 and Nrarp, and increased endothelial Notch signaling activity in areas of the decidua with remodeling angiogenesis. This correlated with an increase in Dll4 expression in capillary endothelial cells, but not spiral artery endothelial cells. Consistent with increased Dll4/Notch signaling, we observed decreased VEGFR2 expression and endothelial cell proliferation in angiogenic decidual capillaries. Despite aberrant Dll4 expression and Notch activation in Jag1∆EC mutants, pregnancies were maintained and the decidual vasculature was not altered up to embryonic day 7.5. Thus, Jag1 functions in the newly formed decidual capillaries as an antagonist of endothelial Dll4/Notch signaling during angiogenesis, but Jag1 signaling is not necessary for early uterine angiogenesis.

The International Particle Accelerator Conference (IPAC) is the main international event for the worldwide accelerator community and industry. It is the venue where researchers present cutting-edge accelerator developments and the latest status of accelerator facilities across the globe. The 9th IPAC, IPAC’18, was held in Vancouver, British Columbia from April 29 to May 4, 2018. With almost 1300 delegates and 90 industrial exhibitors, over 1500 submitted papers, the conference delivered a natural hub for scientific discussion, collaboration meetings and discussions with public program managers and industry and made it a very successful conference. Some conference statistics and scientific high lights will be presented.The International Particle Accelerator Conference (IPAC) is the main international event for the worldwide accelerator community and industry. It is the venue where researchers present cutting-edge accelerator developments and the latest status of accelerator facilities across the globe. The 9th IPAC, IPAC’18, was held in Vancouver, British Columbia from April 29 to May 4, 2018. With almost 1300 delegates and 90 industrial exhibitors, over 1500 submitted papers, the conference delivered a natural hub for scientific discussion, collaboration meetings and discussions with public program managers and industry and made it a very successful conference. Some conference statistics and scientific high lights will be presented.

The use of goat browsing for invasive plant management is growing in the United States, but many questions remain about the efficacy of goat browsing for invasive plant control. One common concern of land managers and other stakeholders is whether goats can spread invasive plants through endozoochory (seed dispersal via ingestion and excretion in feces). We evaluated this possibility using common buckthorn (Rhamnus cathartica), an invasive shrub for which goats are often employed as a control method. Goats were fed buckthorn berries, and their feces were collected and examined at 24 hr, 48 hr, and 72 hr post-ingestion for intact seeds that survived gut passage. A low proportion of buckthorn seeds (2%) made it through the goat digestive system intact. Of these, only 11% remained viable, compared to 63% viability of control seeds. We conclude that consumption of buckthorn fruits by goats effectively destroys seeds, indicating low risk of dispersal via gut passage. To put these results in context, and provide more guidance for land managers, we additionally reviewed literature investigating seed recovery following ingestion by goats. Based on a synthetic analysis across 28 plant species, we found that seeds >4 mm long were unlikely to be recovered from feces intact, while smaller seeds posed higher dispersal risk.

The low energy excited $0_{2,3}^+$ states in $^{96}$Sr are amongst the most prominent examples of shape coexistence across the nuclear landscape. In this work, the neutron $[2s_{1/2}]^2$ content of the $0_{1,2,3}^+$ states in $^{96}$Sr was determined by means of the d($^{95}$Sr,p) transfer reaction at the TRIUMF-ISAC2 facility using the SHARC and TIGRESS arrays. Spectroscopic factors of 0.19(3) and 0.22(3) were extracted for the $^{96}$Sr ground and 1229~keV $0^+$ states, respectively, by fitting the experimental angular distributions to DWBA reaction model calculations. A detailed analysis of the $\gamma$-decay of the isomeric $0_3^+$ state was used to determine a spectroscopic factor of 0.33(13). The experimental results are compared to shell model calculations, which predict negligible spectroscopic strength for the excited $0^+$ states in $^{96}$Sr. The strengths of the excited $0_{2,3}^+$ states were also analyzed within a two-level mixing model and are consistent with a mixing strength of $a^2$=0.40(14) and a difference in intrinsic deformations of $|\Delta \beta|=0.31(3)$. These results suggest coexistence of three different configurations in $^{96}$Sr and strong shape mixing of the two excited $0^+$ states., Comment: Phys Lett B accepted

The Black Guillemot (Cepphus grylle) is a monomorphic seabird characterized by its muted plumage and bright red feet, which it prominently displays during courtship. Foot color and oxidative stress were analyzed in a Black Guillemot colony at the Bay of Fundy during the 2006 and 2007 breeding seasons. While no relationship between red intensity of feet and carotenoids was uncovered, the level of plasma oxidative damage was negatively correlated with foot color. Additionally, red intensity of male feet was significantly correlated with the red intensity of their mates' feet, suggesting the possibility of assortative mating by foot color in this species. Further experimental work is necessary to determine whether foot color is used in this species as an honest signal to relay information on the ability of an individual to manage oxidative stress.

Infections of one host by multiple parasites are common, and several studies have found that the order of parasite invasion can affect both within-host competition and disease severity. However, it is unclear to what extent coinfection timing might be important to consider when modeling parasite impacts on host populations. Using a model system of two viruses infecting barley, we found that simultaneous infections of the two viruses were significantly more damaging to hosts than sequential coinfections. While priority effects were evident in within-host concentrations of sequential coinfections, priority did not influence any parameters (such as virulence or transmission rate) that affect host population dynamics. We built a susceptible-infected model to examine whether the observed difference in coinfection virulence could impact host population dynamics under a range of scenarios. We found that coinfection timing can have an important but context-dependent effect on projected host population dynamics. Studies that examine only simultaneous coinfections could inflate disease impact predictions.

CANREB (CANadian Rare isotope facility with Electron Beam ion source) at TRIUMF will deliver pure, highly charged, radioactive ion beams suitable for acceleration in order to perform experiments to investigate nuclear reactions. Radioactive isotopes at TRIUMF are produced by bombarding solid targets with high energy particle beams. Singly charged ions are extracted from an ion source immediately coupled to the target. CANREB will complement the presently used ECRIS based charge state breeder system by providing higher purity beams and extending the available mass range. Ions are first sent through a high resolution mass separator, where most of the isobaric contaminants can be removed. After this, the ions are injected into an RFQ cooler buncher and finally bunches are injected into an EBIS for charge state breeding. The bunch repetition time is set to 10 ms. This will also allow operation with short lived isotopes. To guarantee the short breeding time for the entire mass range up to uranium and to have a high injection efficiency, the EBIS is designed to operate at an electron beam density of up to 20 000 A/cm2. With the EBIS being operated at ultra-high vacuum, and no plasma wall interactions, additional contaminants induced by the charge state breeding process are expected to be significantly reduced compared with the ECRIS. Total beam intensity is limited mainly by space charge in the buncher to about 107 ions per bunch.

Commissioning of the CANREB (CANadian Rare isotope facility with Electron Beam ion source) system and its associated beamlines has recently begun at TRIUMF. At the head of this beamline is an ion source used to produce stable alkaline ions with energy up to 60 keV for the CANREB system. Throughout commissioning, it is essential to have a means of verifying beam quality and ensuring that the required beam parameters along the beamline are met. This is accomplished using tomography reconstruction, which consists of taking one-dimensional scans at different projections and reconstructing an image of the beam in two dimensions using the maximum entropy algorithm. Tomography enables the visualization of the shape of the beam as well as the investigation into the possible presence of aberrations. Initially, tomography reconstruction is performed by using simulated beam profiles at the measurement locations and is then performed by using measured beam profiles. Additionally, these measurements are benchmarked by fitting the initial beam parameters in our beam optics model, and the results are presented.

The acceleration chain of the ISAC facility boosts the energy of both radioactive and stable light and heavy ions for beam delivery to both a medium energy area in ISAC-I and a high energy area in ISAC-II. The post-accelerator comprises a 35.4 MHz RFQ to accelerate beams of A/q ≤ 30 from 2 keV/u to 150 keV/u and a post stripper, 106.1 MHz variable energy drift tube linac (DTL) to accelerate ions of A/q ≤ 6 to a final energy between 0.15 MeV/u to 1.5 MeV/u. A 40 MV superconducting linac further accelerates beam from 1.5 MeV/u to energies above the Coulomb barrier. All linacs operate cw to preserve beam intensity.

The ARIEL project at TRIUMF will greatly expand the variety and availability of radioactive ion beams (RIBs) (Laxdal, Nucl Inst Methods Phys Res B 204:400–409, 2003). The ARIEL front end connects the two ARIEL target stations to the existing ISAC facility to expand delivery to two and eventually three simultaneous RIB beams with up to two simultaneous accelerated beams (Laxdal et al. 2008). The low-energy beam transport lines and mass separators are designed for maximum flexibility to allow a variety of operational modes in order to optimize the radioactive ion beam delivery. A new accelerator path is conceived for high mass delivery from an EBIS charge state breeder. The front-end design utilizes the experience gained in 15 years of ISAC beam delivery.

The ISAC post accelerator comprises an RFQ, DTL and SC-linac. The high energy beam lines connect the linear accelerators as well as deliver the accelerated beams to two different experimental areas. The medium energy beam transport (MEBT) line connects the RFQ to the DTL. The high energy beam transport (HEBT) line connects the DTL to the ISAC-I experimental stations (DRAGON, TUDA-I, GPS). The DTL to superconducting beam (DSB) transport line connects the ISAC-I and ISAC-II linacs. The superconducting energy beam transport (SEBT) line connects the SC linac to the ISAC-II experimental station (TUDA-II, HERACLES, TIGRESS, EMMA and GPS). All these lines have the function of transporting and matching the beams to the downstream sections by manipulating the transverse and longitudinal phase space. They also contain diagnostic devices to measure the beam properties.

Background Previous research has provided compelling support for olfactory dysfunction in schizophrenia patients, their first-degree relatives, and youth at-risk for psychosis. A previous meta-analysis revealed large effect sizes across olfactory tasks but was limited to 2 olfactory tasks and did not examine moderator variables. Thus, the current meta-analysis was undertaken to incorporate additional studies, risk cohorts, olfactory test domains, and moderator variable analyses. Method A meta-analysis was conducted on 67 publications examining olfactory function in schizophrenia patients and 15 publications examining olfactory functioning in youth at-risk for psychosis, first-degree relatives of schizophrenia patients, and individuals with schizotypy. Results Results revealed medium-to-large olfactory deficits in schizophrenia patients though significant heterogeneity was evident. Several variables moderated overall study effects. At-risk youths similarly demonstrated medium-to-large effect sizes, whereas first-degree relatives and individuals with schizotypy showed small effects. Conclusions Findings suggest robust olfactory deficits in schizophrenia and at-risk youths. In schizophrenia, several variables had significant impact on these deficits and warrant consideration in prospective studies. Our findings also indicate that olfactory measures may be a useful marker of schizophrenia risk status.

Wiliwili (Erythrina sandwicensis), an endemic Hawaiian dry forest tree species, is threatened by an invasive gall-forming wasp (Quadrastichus erythrinae) first detected in Hawai‘i in 2005. Eurytoma erythrinae, a predator of Q. erythrinae from Tanzania, was selected as a biological control agent and was released at sites throughout the Hawaiian Islands. To assess the effectiveness of this biocontrol release, we measured the extent of damage attributable to Q. erythrinae wasps in 124 E. sandwicensis trees at the Waikoloa Village Dry Forest Recovery Project before (January, 2009) and after (January, 2011) the release of the parasitoid wasp at this site. Because host spatial distribution has important consequences for the establishment and success of natural enemies such as parasitoids, we took a spatially explicit approach to account for the potential spatial heterogeneity in E. sandwicensis. We observed an increase in galling damage across the population and 21 trees became completely defoliated be...

Early embryonic exposure to maternal glucocorticoids can broadly impact physiology and behaviour across phylogenetically diverse taxa. The transfer of maternal glucocorticoids to offspring may be an inevitable cost associated with poor environmental conditions, or serve as a maternal effect that alters offspring phenotype in preparation for a stressful environment. Regardless, maternal glucocorticoids are likely to have both costs and benefits that are paid and collected over different developmental time periods. We manipulated yolk corticosterone (cort) in domestic chickens ( Gallus domesticus ) to examine the potential impacts of embryonic exposure to maternal stress on the juvenile stress response and cellular ageing. Here, we report that juveniles exposed to experimentally increased cort in ovo had a protracted decline in cort during the recovery phase of the stress response. All birds, regardless of treatment group, shifted to oxidative stress during an acute stress response. In addition, embryonic exposure to cort resulted in higher levels of reactive oxygen metabolites and an over-representation of short telomeres compared with the control birds. In many species, individuals with higher levels of oxidative stress and shorter telomeres have the poorest survival prospects. Given this, long-term costs of glucocorticoid-induced phenotypes may include accelerated ageing and increased mortality.

Telomeres are protective structures at the ends of eukaryotic chromosomes. The loss of telomeres through cell division and oxidative stress is related to cellular aging, organismal growth and disease. In this way, telomeres link molecular and cellular mechanisms with organismal processes, and may explain variation in a number of important life-history traits. Here, we discuss how telomere biology relates to the study of physiological ecology and life history evolution. We emphasize current knowledge on how telomeres may relate to growth, survival and lifespan in natural populations. We finish by examining interesting new connections between telomeres and the glucocorticoid stress response. Glucocorticoids are often employed as indices of physiological condition, and there is evidence that the glucocorticoid stress response is adaptive. We suggest that one way that glucocorticoids impact organismal survival is through elevated oxidative stress and telomere loss. Future work needs to establish and explore the link between the glucocorticoid stress response and telomere shortening in natural populations. If a link is found, it provides an explanatory mechanism by which environmental perturbation impacts life history trajectories.

The spatial arrangement of plants in a landscape influences wind flow, but the extent that differences in the density of con-specifics and the height of surrounding vegetation influence population spread rates of wind dispersed plants is unknown. Wind speeds were measured at the capitulum level in conspecific arrays of different sizes and densities in high and low surrounding vegetation to determine how these factors affect wind speeds and therefore population spread rates of two invasive thistle species of economic importance, Carduus acanthoides and C. nutans. Only the largest and highest density array reduced wind speeds at a central focal thistle plant. The heights of capitula and surrounding vegetation also had significant effects on wind speed. When population spread rates were projected using integrodifference equations coupling previously published demography data with WALD wind dispersal models, large differences in spread rates resulted from differences in average horizontal wind speeds at capitulum height caused by conspecific density and surrounding vegetation height. This result highlights the importance of spatial structure for the calculation of accurate spread rates. The management implication is that if a manager has time to remove a limited number of thistle plants, an isolated thistle growing in low surrounding vegetation should be targeted rather than a similar sized thistle in a high density population with high surrounding vegetation, if the objective is to reduce spread rates.

Nonrandom seed release is an important determinant of how far seeds disperse, but the mechanisms that promote wind-related seed release under varying atmospheric conditions are poorly understood. We explored the use of particle image velocimetry (PIV) to gain a better mechanistic understanding of seed release by visualizing the flow velocities and vorticity in a two-dimensional slice of air around inflorescences. Pilot data taken in a wind tunnel show gradients in air velocity at the top of Carduus nutans capitula that may contribute to lift generation. Additionally, von Kármán vortex streets (vortices of opposite spin that are shed from the wake of an object) were observed shedding from capitula, which cause lateral forces on capitula and increase turbulence downwind at other locations. Avenues for further research include using PIV to examine the mechanisms of seed release and dispersal in wind tunnels and in the field. We found PIV to be a promising method to further explore the mechanisms behind seed release in wind dispersed plants, and a technique rich with opportunities for collaborations between plant dispersal ecologists and fluid dynamics specialists.

Herbivores may significantly reduce plant populations by reducing seed set; however, we know little of their impact on seed movement. We show for the first time that the receptacle-feeding weevil Rhinocyllus conicus not only reduces seed production by the invasive thistle Carduus nutans but also inhibits release and subsequent wind dispersal of seeds. These effects generate large, though different, impacts on spatial spread and local abundance in two populations with differing demography, located in the United States and New Zealand. Furthermore, the mechanism is context dependent, with the largest effects through increased terminal velocity in the United States but through reduced seed production in New Zealand. Our results show that the benefit of biocontrol programs may have been underestimated; screenings of potential biocontrol agents should examine effects on pest dispersal and spread, as well as on abundance.

This paper presents the results of an experimental investigation about the performance of a horizontal flow high-rate pilot scale Dissolved Air Flotation (HRDAF) unit containing inclined parallel plates for treating a coloured and low turbidity raw water. Experiments were performed with the DAF unit in order to verify the influence on flotation of : (i) the water velocity (Vh) between the plates, in the range 18 to 96.5 cm.min −1 with corresponding Reynolds numbers between 240 and 1060; (ii) the supplied air (S*) value ranging from 2.2 to 8.5 g of air/m 3 of water ; (iii) the angle of the plates (60° or 70°). The best pilot plant operational condition was obtained applying only 4.0 g/m 3 (S*) with Vh around 18 cm.min −1 for treatment of water coagulated with a Al 2 (SO 4 ) 3 dosage of 40 mg.l −1 . In these conditions, the unit presented very good removal efficiencies of colour (90%, residual of 10 uC), turbidity (88%, residual of 0.8 NTU ) and TSS (94%, residual of 1.8 mg.l −1 ). Furthermore, the unit could operate at higher Vh values up to 76 cm.min −1 and still present good results. The DAF unit thus behaved as a high rate unit presenting good performance with low air requirement.

Despite the well-documented observation of odor identification deficits in schizophrenia, less is known about where the disruption in the process of correctly identifying an odor occurs. This study aimed to determine the potential moderating effects of semantic processing on the observed olfactory dysfunction in schizophrenia. Schizophrenia patients and healthy comparison subjects completed two versions of the University of Pennsylvania Smell Identification Test (UPSIT): an uncued free-response version and the standard multiple-choice paradigm, as well as three semantic measures: The Boston Naming Test, Animal Naming, and Pyramids and Palm Tree Test. Schizophrenia patients yielded significantly lower scores than the comparison group on the standard UPSIT and on semantic measures. No relationship was observed between olfactory and semantic task performance in patients. These data suggest that odor identification deficits may not be primarily due to semantic processing deficits in schizophrenia.

Background : Non-random seed release caused by plant responses to weather conditions is important for seed dispersal. Much is known about the effects of wind speed and turbulence, but our understanding of the effects of water loss on seed release is either qualitative, or indirect and phenomenological. Aims : To quantify the empirical relationship between water loss and seed release. Methods : Capitula of the invasive thistles Carduus acanthoides and C. nutans were collected from the field and treated for either 0, 1 or 2 days in the laboratory at three different vapour pressure deficit levels (3.4, 9.5 and 17.0 hPa) to cause a range of water loss values. Total seed release was quantified before and during wind tunnel trials. Results : Water loss was the only significant predictor of whether or not capitula released any seeds. The number of seeds released was predicted by water loss, capitulum diameter and herbivore damage, with the same amount of water loss having less effect on larger capitula. Conclusi...

The use of valve-regulated lead/acid batteries (VRLA) in automotive applications provides some important advantages with respect to traditional flooded designs. Difficulties are reported for flooded lead/acid batteries that use PbCa alloys in the positive grids with respect to recovery of capacity after deep discharge. This problem is no longer valid for recombinant batteries using absortive glass-mat (AGM) separators. Further, this truly maintenance-free battery can be installed in any position, even outside the engine compartment, because of the absence of gas emission or electrolyte spillage. The shelf life is very long and the battery can be stored at open circuit for 12 months with no significant loss of performance. The cold-cranking capacity is higher than the equivalent conventional lead/acid battery due to the reduced internal resistance.

Mechanistic models of seed dispersal by wind include terminal velocity as the main seed characteristic that influences the dispersal process and hence the resulting dispersal kernels and spread rates. Accurate measurement of the terminal velocity of seeds is therefore pivotal. However, compression during shipment through the post or during storage between collection in the field and terminal velocity measurements in the lab may affect these measurements. To evaluate the effects of shipment and storage on terminal velocity measurements, capitula of Carduus nutans, an invasive thistle species from Eurasia, were stored for 1–5 years and subjected to three different packing treatments. Seeds from capitula were then assessed for terminal velocity values, plume area, seed mass, wing loading, number of filaments per pappus, qualitative assessments of pappus damage, and number of intact dispersal units per capitulum. Compression significantly increased seed terminal velocity. However, storage duration for 1–5 years did not cause a significant increase or decrease in any of the response variables. The compression treatment was validated by shipment of seeds from New Zealand to the United States. When capitula that are to be used for terminal velocity measurements are stored or shipped, they should be packaged in incompressible containers to avoid damage to the fragile dispersal structures. Studies using capitula that were originally collected and stored for other purposes, such as transcontinental demographic studies, should rescale observed terminal velocity values to take into account possible damage.

The off-line ion source (OLIS) terminal consists of a microwave cusp ion source, either a surface ion source or a hybrid surface-arc discharge ion source and an electrostatic switch that allows selecting any one of the sources without mechanical intervention. These sources provide variety of beams to ISAC experiments, for commissioning the accelerators, for setting up the radioactive experiments, and for tuning the beam lines. The microwave ion source has been operational since 1995 and provides singly and doubly charged beams from various stable isotopes for many ISAC experiments at high and low energy areas. Originally its prime goal was to provide beams from gaseous elements, but later two ovens and a sputtering system were added in order to provide beams from liquids and from solids. The surface ion source installed in 2002 can provide low energy spread beams from alkali and semialkali elements. It also has three separate ovens and an ionizer. Therefore, it can provide three different temperature regions simultaneously to provide different beams to ISAC. It is mainly used for laser spectroscopy experiments and other experiments, which require a finite beam quality. A hybrid surface-arc discharge ion source was also developed and installed in order to meet specific demands from experiments. This source terminal is now automated for start up and for mass selection. It is capable of providing stable beams for months without maintenance and it is also capable of providing negative ion beams if required. To date, over 40 different isotopes including many rear isotopes were delivered to various experiments from the OLIS source terminal. Performances of the ion sources and some of the results are discussed.

At the Isotope Separation and ACceleration (ISAC) facility at TRIUMF, an electron cyclotron resonance ion source (ECRIS) has been set up for the charge state breeding of radioactive ions. In order to reduce background from stable ions generated in the ECRIS, several measures, including changing materials for the plasma chamber and the surrounding components, have been implemented. Further reduction has been achieved by using the post-accelerator chain as a mass filter. Since the implementation of those measures in 2013, physics experiments with accelerated radioactive isotopes of Rb, Sr, K, and Mg have been performed. In most cases, a charge breeding efficiency of several percent has been achieved. With the planned expansion of the isotope production capabilities at TRIUMF within the Advanced Rare IsotopE Laboratory project, two new target stations, one using photo-fission induced by a high-power electron beam at 50 MeV and the other one using 480 MeV protons as at ISAC, will be put into operation within the next 5 yr. Additionally, a new electron beam ion source (EBIS) based charge state breeding system will be installed. Background from such a source is expected to be much lower. The drawback is that for the efficient operation of such a system, pulsed beam operation is required, which makes the installation of an additional ion buncher in front of the EBIS necessary.