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The hemlock woolly adelgid, Adelges tsugaeAnnand (Hemiptera: Adelgidae), is an invasive pest causing significant ecological and economic damage to certain hemlock tree (Tsuga(Endlicher) Carrière, Pinales:Pinaceae) species. In response to this invasive threat, biological control strategies have been implemented, introducing natural predators such as Laricobius nigrinusFender (Coleoptera: Derodontidae) and, more recently, Laricobius osakensisMontgomery and Shiyake (Coleoptera: Derodontidae), as specialist predators against A. tsugae. However, the genetic and morphological similarities between L. osakensisand both L. nigrinusand the native beetle, Laricobius rubidusLeConte (Coleoptera: Derodontidae), pose challenges in their identification. Effective monitoring of released predators is integral to evaluating the success of biological control measures. Environmental DNA (eDNA) holds potential for various detection applications, including species monitoring. In this study, we developed specific primers and probes targeting the mitochondrial cytochrome oxidase 1 gene sequences, achieving high specificity despite their 95% sequence similarity. With an optimal annealing temperature of 60 °C, our tools effectively differentiated L. osakensisfrom the other 2 beetles and demonstrated eDNA detection sensitivity down to 2 copies/µl. This research underscores the potential of precise molecular tools for advancing biological control and biodiversity assessment against invasive threats like A. tsugae.

Increasing efficiency of data gathering at the landscape scale on the growing number of pests and pathogens threatening forests worldwide has potential to improve management outcomes. Citizen science is expanding, with growing support and utility in environmental and conservation fields. We present a case study showing how citizen science observations can be used to inform research and management of a devastating forest pest. Hemlock woolly adelgid, Adelges tsugaeAnnand (Hemiptera: Adelgidae), was introduced to eastern North America, leading to decline and mortality of eastern [Tsuga canadensis(L.) Carrière] (Pinales: Pinaceae) and Carolina hemlock (Tsuga carolinianaEngelmann) trees. Management activities, most notably biological control, rely on observations of A. tsugaephenology to inform the timing of releases and monitoring surveys of their highly synchronized specialist predators. In this article, we outline a citizen science program and report phenological observations on A. tsugae. Additionally, we report data comparing A. tsugaeestivation break in Virginia (VA) and New York (NY) State, revealing that estivation break is synchronized between NY and VA. This observation is supported by 6 years of citizen scientist observations, showing similar patterns throughout NY, with egg laying shown to be much more variable than estivation break.

In hemlock stands within eastern US forests, classical biological control has been one of the main strategies used to manage the hemlock woolly adelgid, Adelges tsugaeAnnand. Specialist predator species may offer a management solution to help regulate A. tsugaepopulations. In the Pacific Northwest, a suite of specialist predators has been a focus of research and includes 2 species of silver fly, Leucotaraxis argenticollis(Zetterstedt) and Leucotaraxis piniperda(Malloch) (Diptera: Chamaemyiidae). Leucotaraxisspp. phenology has been documented in the Pacific Northwest, but the phenology of either western Leucotaraxisspecies is unknown in the eastern United States. This study sought to document the phenology of Le. argenticollisin NY in 2021 and in VA in 2021 and 2022. Nylon mesh cages were applied over eastern hemlock branches infested with A. tsugaeto contain Le. argenticollisadults. Biweekly and monthly branch samples were taken in 2021 and 2022, documenting all life stages of A. tsugaeand of Le. argenticollisthat were observed. In 2021 and 2022, Le. argenticollisadults and eggs were present during the oviposition stage of the 2 generations of A. tsugae. In addition, Le. argenticollislarvae were present when A. tsugaeovisacs had eggs and while A. tsugaenymphs of both generations were present. These observations indicate that Le. argenticollisphenology is well synchronized with A. tsugaein the eastern United States.

Efficient separation of insects from plant material for quantification and collection is an important component of entomological research. This paper reports on a novel, easily replicable container designed to efficiently collect two different biological control agents dispersing from hemlock (Tsugaspp.) foliage infested with the invasive hemlock woolly adelgid (HWA), Adelges tsugaeAnnand (Hemiptera: Adelgidae). The container utilizes a simplified Berlese-style funnel design to collect Laricobiusspp. (Coleoptera: Derodontidae) larvae dropping from the foliage into a removable bottom jar, a central jar to house the foliage sample, and a removable top jar to collect adult silver flies (Leucopisspp., Diptera: Chamaemyiidae) emerging from puparia on the twigs. The efficacy of two designs (with and without a funnel leading to the top collection jar) was evaluated using western hemlock [Tsuga heterophylla(Raf.) Sarg.] foliage naturally colonized with HWA and the two predator genera. All Laricobiuslarvae were effectively collected in the bottom jar, and the addition of an inverted funnel leading to the top collection jar increased the proportion of Leucopisflies reaching the target jar from 60% to 94%. This ‘Lari-Leuco’ container is presented as a research and motoring tool to benefit the integrated pest management program for HWA in eastern North America and for potential use in simultaneously separating ascending and descending life stages in other insect-plant or predator-prey systems.

AbstractAdelges tsugaeAnnand (Hemiptera: Adelgidae), a nonindigenous insect pest of hemlock (Tsugaspp.) (Pinaceae) in eastern North America, spends most of its life cycle within an ovisac, which resembles a woolly white mass on twigs. We evaluated the probability of detecting adelgid wool with Velcro®-covered balls when taking an increasing number of samples per tree (field sampling) and number of trees per simulated stand. We examined the relationship between the detection of adelgid wool using this technique and the incidence of A. tsugae-infested twigs by sampling lower-crown branch tips of the same trees. We found that the probability of detecting wool with ball sampling increased with number of ball samples per tree, with number of trees per simulated stand, and with increasing incidence of ovisacs in the lower crown. When sampling an individual tree, we found that 20 ball samples per tree achieved a targeted precision level of 0.75, but when sampling a stand, we found that 10 ball samples per tree took the least time for the range of simulated A. tsugaeinfestations we tested. These sample sizes are recommended for detection of A. tsugaeinfestations on an individual tree and in a hemlock stand.

We developed an approach using sticky trap arrays as an early detection tool for populations of first-instar nymphs of the hemlock woolly adelgid (Adelges tsugaeAnnand), a pest of hemlocks (Tsugaspp. [Pinaceae]) in North America. We considered the detection rate of at least one nymph from trapping arrays consisting of one to six sticky panels, where we varied both the surface area of each trap that we assessed and the length of the trapping duration. We also estimated the time needed to set up, service, and assess groups of traps and attempted to relate capture of nymphs on traps to incidence and abundance of A. tsugaein the canopy above the traps. Arrays consisting of two traps provided a detection rate of 75% when 87.5% of the surface area of each trap was assessed, a process that required 38 min per array. The probability of detecting nymphs on traps left in the field for 5–6 d was similar to that for traps left for 12 d. The number of nymphs trapped in an array predicted the probability of finding A. tsugaein the canopy but only when all six traps were fully assessed. To reliably detect incipient A. tsugaeinfestations, we recommend placing arrays of traps at 1 km intervals along the perimeter of a stand during peak activity of first-instar sistentes nymphs and servicing these arrays every 5–7 d.

AbstractAdelges tsugaeAnnand (Hemiptera: Adelgidae) has caused extensive mortality of hemlocks (Tsuga(Endlicher) Carrière; Pinaceae) in the eastern United States of America and was discovered recently in Nova Scotia, Canada. We evaluated the use of a Velcro-covered racquetball as a sampling device for A. tsugaewool. Specifically, we report on improvements to an earlier design and evaluate several factors seen in routine sampling that influence the ability of the ball to trap and retain adelgid wool. Velcro was found to be critical for trapping and retaining adelgid wool on the ball during flight and landing. Wooden beads, inserted in the ball, reduced deflection during flight and bounce during landing. Higher probability of trapping wool on the ball was associated with an ascent through the crown, with increasing diameter and density of ovisacs on branch tips, and with increasing abundance of woolly twigs on the forest floor. Higher probability of retaining wool on the ball was associated with Velcro surface area and with amount and location of wool loaded on the ball. These modifications improved detection surveys for A. tsugaein general.

AbstractDetection of the exotic hemlock woolly adelgid, Adelges tsugaeAnnand (Hemiptera: Adelgidae), in the crown of eastern hemlock, Tsuga canadensis(Linnaeus) Carrière (Pinaceae), relies mainly on two techniques: (1) sampling of branches from the lower half of the crown using pole pruners; and, (2) visual examinations of accessible foliage from the ground. As a result, infestations starting elsewhere than the lower crown may be missed because the upper crown is out of reach for both techniques. We developed a novel technique called ball sampling, and evaluated its sensitivity at detecting a range of A. tsugaeovisac densities as estimated by pole pruning branch tips of T. canadensis. We launched racquet balls covered with VELCRO®patches of hooks through branches and examined them for the presence of wool produced by A. tsugae.Ball sampling was as effective as pole pruning at detecting infestations in individual trees. If A. tsugaeabundance on branches was ?0.1 per 10 cm of twig length, as estimated by branch-tip sampling, ball sampling always detected wool in 10 or fewer samples. This technique has the potential to improve detectability of A. tsugaeinfestations because it can effectively access foliage that is typically inaccessible to other ground-based detection tools.

AbstractThe systemic inflammatory response syndrome (SIRS) is a clinical condition occurring in intensive care unit patients as a consequence of both infectious and noninfectious insults. The mechanisms underlying resolution of SIRS are not well characterized. NOX2 (NADPH oxidase 2)-derived reactive oxygen species are critical for killing of certain pathogens by polymorphonuclear leukocytes (PMN). Patients with chronic granulomatous disease who lack functional NOX2 are not only prone to serious infections, they also exhibit chronic inflammatory conditions, suggesting a local anti-inflammatory role for NOX2. We hypothesized that NOX2 is required for the resolution of sterile systemic inflammation. Using a murine model of sterile generalized inflammation, we observed dramatically increased mortality of gp91phox-/y(NOX2-deficient) as compared to wild-type (WT) mice. Both genotypes developed robust SIRS with hypothermia, hypotension, and leukopenia; however, WT mice recovered within 48 h whereas NOX2-deficient mice did not. Although both groups displayed rapid peritoneal PMN recruitment, the recruited NOX2-deficient PMN demonstrated an enhanced inflammatory phenotype. Moreover, NOX2-deficient mice exhibited a hemorrhagic inflammatory response in the lungs with rapid and persistent recruitment of neutrophils to the alveolar space, whereas WT mice had minimal lung pathology. Several proinflammatory cytokines remained elevated in NOX2-deficient mice. The persistent inflammatory environment observed in NOX2-deficient mice resulted from continued peritoneal chemokine secretion and not delayed apoptosis of PMN. These data suggest a requirement for NOX2 in the resolution of systemic inflammation.Copyright © 2013 S. Karger AG, Basel

Patient-centered medical homes (PCMHs) are intended to actively provide effective care by physician-led teams, where patients take a leading role and responsibility.

Chikungunya virus (CHIKV), an emerging mosquito-borne Alphavirus, causes debilitating rheumatic disease in humans that can last for weeks to months. Starting in 2004, a CHIKV outbreak in the Indian Ocean region affected millions of people, and infected travelers introduced CHIKV to new regions. The pathogenesis of CHIKV is poorly understood, and no approved vaccines or specific therapies exist. A major challenge to the study of CHIKV disease is the lack of a small animal model that recapitulates the major outcomes of human infection. In this study, the pathogenesis of CHIKV in C57BL/6J mice was investigated using biological and molecular clones of CHIKV isolated from human serum (CHIKV SL15649). After 14-day-old mice were inoculated with CHIKV SL15649 in the footpad, they displayed reduced weight gain and swelling of the inoculated limb. Histologic analysis of hind limb sections revealed severe necrotizing myositis, mixed inflammatory cell arthritis, chronic active tenosynovitis, and multifocal vasculitis. Interestingly, these disease signs and viral RNA persisted in musculoskeletal tissues for at least 3 weeks after inoculation. This work demonstrates the development of a mouse model of CHIKV infection with clinical manifestations and histopathologic findings that are consistent with the disease signs of CHIKV-infected humans, providing a useful tool for studying viral and host factors that drive CHIKV pathogenesis and for evaluating potential therapeutics against this emerging viral disease.

Early Release Science observations of the cluster NGC 3603 with the WFC3 on the refurbished Hubble Space Telescope allow us to study its recent star formation history. Our analysis focuses on stars with Ha excess emission, a robust indicator of their pre-main sequence (PMS) accreting status. The comparison with theoretical PMS isochrones shows that 2/3 of the objects with Ha excess emission have ages from 1 to 10 Myr, with a median value of 3 Myr, while a surprising 1/3 of them are older than 10 Myr. The study of the spatial distribution of these PMS stars allows us to confirm their cluster membership and to statistically separate them from field stars. This result establishes unambiguously for the first time that star formation in and around the cluster has been ongoing for at least 10-20 Myr, at an apparently increasing rate.

The newly installed Wide Field Camera 3 (WFC3) on the Hubble Space Telescope has been used to obtain multi-band images of the nearby spiral galaxy M83. These new observations are the deepest and highest resolution images ever taken of a grand-design spiral, particularly in the near-ultraviolet, and allow us to better differentiate compact star clusters from individual stars and to measure the luminosities of even faint clusters in the U band. We find that the luminosity function (LF) for clusters outside of the very crowded starburst nucleus can be approximated by a power law, dN/dL [?] L a, with a = -2.04 +- 0.08, down to MV [?] -5.5. We test the sensitivity of the LF to different selection techniques, filters, binning, and aperture correction determinations, and find that none of these contribute significantly to uncertainties in a. We estimate ages and masses for the clusters by comparing their measured UBVI, Ha colors with predictions from single stellar population models. The age distribution of the clusters can be approximated by a power law, dN/dt [?] tg, with g = -0.9 +- 0.2, for M [?] few x 103 M and t [?] 4 x 108 yr. This indicates that clusters are disrupted quickly, with [?]80%-90% disrupted each decade in age over this time. The mass function of clusters over the same M-t range is a power law, dN/dM [?] M b, with b = -1.94 +- 0.16, and does not have bends or show curvature at either high or low masses. Therefore, we do not find evidence for a physical upper mass limit, MC , or for the earlier disruption of lower mass clusters when compared with higher mass clusters, i.e., mass-dependent disruption. We briefly discuss these implications for the formation and disruption of the clusters.

The age distribution of star clusters in nearby galaxies plays a crucial role in evaluating the lifetimes and disruption mechanisms of the clusters. Two very different results have been recently found for the age distribution kh(t) of clusters in the Large Magellanic Cloud (LMC). We found that kh(t) can be approximately described by a power law kh(t) [?] tg, with g [?] -0.8, by counting clusters in the mass-age plane, i.e., by constructing kh(t) directly from mass-limited samples. Gieles & Bastian inferred a value of g [?] 0, based on the slope of the relation between the maximum mass of clusters in equal intervals of log t, hereafter, the M max method, an indirect technique that requires additional assumptions about the upper end of the mass function. However, our own analysis shows that the M max method gives a result consistent with our direct counting method for clusters in the LMC, namely, kh(t) [?] t-0.8 for t [?] 109 yr. The reason for the apparent discrepancy is that our analysis includes many intermediate and high-mass clusters (M > 1.5 x 103 M ), which formed recently (t [?] 107 yr), and which are known to exist in the LMC, whereas Gieles & Bastian are missing such clusters. We compile recent results from the literature showing that the age distribution of young star clusters in more than a dozen galaxies, including dwarf and giant galaxies, isolated and interacting galaxies, and irregular and spiral galaxies, has a similar declining shape. We interpret this approximately "universal" shape as primarily due to the progressive disruption of star clusters over their first [?]few x 108 yr, starting soon after formation, and discuss some observational and physical implications of this early disruption for stellar populations in galaxies.

We compare the observed bivariate distribution of masses (M) and ages (t) of star clusters in the Large Magellanic Cloud (LMC) with the predicted distributions g(M, t) from three idealized models for the disruption of star clusters: (1) sudden mass-dependent disruption, (2) gradual mass-dependent disruption, and (3) gradual mass-independent disruption. The model with mass-independent disruption provides a good, first-order description of these cluster populations, with g(M, t) [?] M btg, b = -1.8 +- 0.2 and g = -0.8 +- 0.2, at least for clusters with ages t [?] 109 yr and masses M [?] 103 M (more specifically, t [?] 107(M/102 M )1.3 yr). This model predicts that the clusters should have a power-law luminosity function, dN/dL [?] L -1.8, in agreement with observations. The first two models, on the other hand, fare poorly when describing the observations, refuting previous claims that mass-dependent disruption of star clusters is observed in the LMC over the studied M-t domain. Clusters in the SMC can be described by the same g(M, t) distribution as for the LMC, but with smaller samples and hence larger uncertainties. The successful g(M, t) model for clusters in the Magellanic Clouds is virtually the same as the one for clusters in the merging Antennae galaxies, but extends the domain of validity to lower masses and to older ages. This indicates that the dominant disruption processes are similar in these very different galaxies over at least t [?] 108 yr and possibly t [?] 109 yr. The mass functions for young clusters in the LMC are power laws, while that for ancient globular clusters is peaked. We show that the observed shapes of these mass functions are consistent with expectations from the simple evaporation model presented by McLaughlin & Fall.

We present Wide Field Camera 3 images taken with the Hubble Space Telescope within a single field in the southern grand design star-forming galaxy M83. Based on their size, morphology, and photometry in continuum-subtracted Ha, [S II], Hb, [O III], and [O II] filters, we have identified 60 supernova remnant (SNR) candidates, as well as a handful of young ejecta-dominated candidates. A catalog of these remnants, their sizes and, where possible, their Ha fluxes are given. Radiative ages and pre-shock densities are derived from those SNRs that have good photometry. The ages lie in the range 2.62 < log (trad/yr) < 5.0, and the pre-shock densities at the blast wave range over 0.56 < n 0/cm-3 < 1680. Two populations of SNRs have been discovered. These divide into a nuclear and spiral arm group and an inter-arm population. We infer an arm to inter-arm density contrast of 4. The surface flux in diffuse X-rays is correlated with the inferred pre-shock density, indicating that the warm interstellar medium (ISM) is pressurized by the hot X-ray plasma. We also find that the ISM in the nuclear region of M83 is characterized by a very high porosity and pressure, and infer an SNR rate of 1 per 70-150 yr for the nuclear (R < 300 pc) region. On the basis of the number of SNRs detected and their radiative ages, we infer that the lower mass of Type II SNe in M83 is M min = 16+7 -5 M . Finally, we give evidence for the likely detection of the remnant of the historical supernova, SN1968L.

We present new tests for disruption mechanisms of star clusters based on the bivariate mass-age distribution g(M, t). In particular, we derive formulae for g(M, t) for two idealized models in which the rate of disruption depends on the masses of the clusters and one in which it does not. We then compare these models with our Hubble Space Telescope observations of star clusters in the Antennae galaxies over the mass-age domain in which we can readily distinguish clusters from individual stars: t [?] 107(M/104 M )1.3 yr. We find that the models with mass-dependent disruption are poor fits to the data, even with complete freedom to adjust several parameters, while the model with mass-independent disruption is a good fit. The successful model has the simple form g(M, t) [?] M -2t-1, with power-law mass and age distributions, dN/dM [?] M -2 and dN/dt [?] t-1. The predicted luminosity function is also a power law, dN/dL [?] L -2, in good agreement with our observations of the Antennae clusters. The similarity of the mass functions of star clusters and molecular clouds indicates that the efficiency of star formation in the clouds is roughly independent of their masses. The age distribution of the massive young clusters is plausibly explained by the following combination of disruption mechanisms: (1) removal of interstellar material by stellar feedback, t [?] 107 yr; (2) continued stellar mass loss, 107 yr [?] t [?] 108 yr; (3) tidal disturbances by passing molecular clouds, t [?] 108 yr. None of these processes is expected to have a strong dependence on mass, consistent with our observations of the Antennae clusters. We speculate that this simple picture also applies--at least approximately--to the clusters in many other galaxies.

The provenance of gem stones has been of interest to geologists, gemologists, archeologists, and historians for centuries. Laser induced breakdown spectroscopy (LIBS) provides a minimally destructive tool for recording the rich chemical signatures of gem beryls (aquamarine, goshenite, heliodor, and morganite). Broadband LIBS spectra of 39 beryl (Be_3Al_2Si_6O_18) specimens from 11 pegmatite mines in New Hampshire, Connecticut, and Maine (USA) are used to assess the potential of using principal component analysis of LIBS spectra to determine specimen provenance. Using this technique, beryls from the three beryl-bearing zones in the Palermo #1 pegmatite (New Hampshire) can be recognized. However, the compositional variation within this single mine is comparable to that in beryls from all three states. Thus, a very large database with detailed location metadata will be required to routinely determine gem beryl provenance.

We present extensive new photometry in (g', i') of the large globular cluster (GC) system around NGC 3311, the central cD galaxy in the Hydra cluster. Our GMOS data cover a 5.5 ' field of view and reach a limiting magnitude i' [?] 26.0, about 0.5 mag fainter than the turnover point of the GC luminosity function. We find that NGC 3311 has a huge population of [?]16,000 GCs, closely similar to the prototypical "high specific frequency" Virgo giant M87. The color-magnitude distribution shows that the metal-poor "blue" GC sequence and the more metal-rich "red" sequence are both present, with nearly equal numbers of clusters. Bimodal fits to the color distributions confirm that the blue sequence shows the same trend of progressively increasing metallicity with GC mass that has previously been found in many other large galaxies; the correlation we find corresponds to a scaling of GC metallicity with mass of Z [?] M0.6. By contrast, the red sequence shows no change of mean metallicity with mass but does show an upward extension to much higher than normal luminosity into the UCD-like range, strengthening the potential connections between massive GCs and UCDs. The GC luminosity function, which we measure down to the turnover point at MI[?] [?] 8.4, also has a normal form like those in other giant ellipticals. Within the Hydra field, another giant elliptical NGC 3309 is sitting just 100 '' from the cD NGC 3311. We use our data to solve simultaneously for the spatial structure and total GC populations of both galaxies. Their specific frequencies are SN(N 3311) = 12.5 +- 1.5 and SN(N 3309) = 0.6 +- 0.4. NGC 3311 is completely dominant and entirely comparable with other cD-type systems such as M87 in Virgo.

‘Clearwater’ (Reg. No. CV‐335; PI 647080) is a spring two‐rowed barley (Hordeum vulgareL.) developed by the USDA‐ARS and the Idaho Agricultural Experiment Station. Clearwater was selected and released on the basis of competitive agronomic performance in combination with low‐phytate (LP), hulless grain. Clearwater derives from an BC1F3:4selection from the cross ‘Baronesse’*2/Pmut640//HB317. It was tested under the experimental designation 01ID435H. The parent Pmut640 is a sodium‐azide generated mutant induced in the two‐rowed malting cultivar Harrington. The mutation conferring reduced phytate in Pmut640 is believed to be allelic to lpa2‐1, which results in a reduction of phytate (myo‐inositol 1,2,3,4,5,6‐hexakisphosphate) of approximately 40 to 50% and an increase in inorganic P of greater than 400%. Studies have shown that these changes are associated with increased feed quality and reduced environmental impacts when fed to non‐ruminant animals, based on increased P digestibility and reduced fecal P content.

Abstract:Point counts are one of the most widely used and efficient approaches to survey land-bird populations. A new approach to point-count surveys involves the use of 2 observers, which allows the calculation of a detection probability for each bird species. Detection probabilities derived from 2 observers permit investigators to calculate a corrected abundance estimate that accounts for birds present but not detected. We evaluated 2 double-observer point count approaches: the dependent-observer approach and the independent-observer approach. The dependent-observer approach involves 2 observers recording data together on a single data sheet with one observer designated the primary observer and the other designated as the secondary observer. The primary observer verbally dictates the number of each species detected while the secondary observer records this information; the secondary observer also records birds that the primary observer did not detect. The independent-observer approach involves 2 observers recording data independently on separate data sheets without verbal communication between observers. This study compares the detection probabilities and associated levels of precision generated by both double-observer approaches to ascertain which technique generates data that are more accurate and more feasible to apply in the field. We conducted point counts at 137 point locations in northern West Virginia during the spring of 2000 and 2001 using both double-observer approaches. We generated detection probabilities and abundances from data collected using both double-observer approaches using program DOBSERV. The dependent-observer approach resulted in higher observer-specific and joint detection probabilities, as well as lower standard errors of detection probability across most cover types. Species-specific detection probabilities were higher across all cover types under the dependent-observer approach. Given the higher detection probabilities and associated precision combined with fewer logistical constraints, we suggest that the dependent-observer approach be used when investigators are interested in surveying birds using point counts.

We present new (B, I) photometry for the globular cluster systems in eight brightest cluster galaxies (BCGs), obtained with the ACS/WFC camera on the Hubble Space Telescope. In the very rich cluster systems that reside within these giant galaxies, we find that all have strongly bimodal color distributions that are clearly resolved by the metallicity-sensitive (B - I) index. Furthermore, the mean colors and internal color range of the blue subpopulation are remarkably similar from one galaxy to the next, to well within the +-0.02-0.03 mag uncertainties in the foreground reddenings and photometric zero points. By contrast, the mean color and internal color range for the red subpopulation differ from one galaxy to the next by twice as much as the blue population. All the BCGs show population gradients, with much higher relative numbers of red clusters within 5 kpc of their centers, consistent with their having formed at later times than the blue, metal-poor population. A striking new feature of the color distributions emerging from our data is that for the brightest clusters (MI < -10.5) the color distribution becomes broad and less obviously bimodal. This effect was first noticed by Ostrov et al. and Dirsch et al. for the Fornax giant NGC 1399; our data suggest that it may be a characteristic of many BCGs and perhaps other large galaxies. Our data indicate that the blue (metal-poor) clusters brighter than MI [?] -10 become progressively redder with increasing luminosity, following a mass/metallicity scaling relation Z ~ M0.55. A basically similar relation has been found for M87 by Strader et al. (2005). We argue that these GCS characteristics are consistent with a hierarchical-merging galaxy formation picture in which the metal-poor clusters formed in protogalactic clouds or dense starburst complexes with gas masses in the range 107-1010 M, but where the more massive clusters on average formed in bigger clouds with deeper potential wells where more preenrichment could occur.

We report on a multiwavelength study of the relationship between young star clusters in the Antennae galaxies (NGC 4038/9) and their interstellar environment, with the goal of understanding the formation and feedback effects of star clusters in merging galaxies. This is possible for the first time because various new observations (from X-rays to radio wavelengths) have become available in the past several years. Quantitative comparisons are made between the positions of the star clusters (broken into three age groups) and the properties of the interstellar medium by calculating the two-point correlation functions. We find that young star clusters are distributed in a clustered fashion, demonstrated by power-law angular autocorrelation functions with slopes in the range -0.8 to -1.0. The young embedded clusters (ages ~5 Myr) are found to be more associated with long-wavelength radiation (mid-infrared and longer), while clusters with ages ~10 Myr or older are more associated with short-wavelength radiation (e.g., far-UV and X-ray). The youngest star clusters are associated with molecular cloud complexes with characteristic radii of about 1 kpc. In addition, there is a weak tendency for them to be found in regions with higher H I velocity dispersions. There is some evidence that both cloud-cloud collisions and shocks from recent star formation can trigger star cluster formation, but no dominant triggering mechanism is identified for the majority of the clusters in the Antennae. Feedback from young bright cluster complexes reveals itself in the form of large Ha bubbles and Ha velocity gradients in shells around the complexes. We estimate the current star formation rate to be [?]20 M yr-1 and the gas consumption timescale to be ~700 Myr. The latter is comparable to the merging timescale and indicates that star formation has been enhanced by the merger event. Finally, we find that the Schmidt law, with index N [?] -1.4, is also a good description of the cluster formation triggered by merging in the Antennae. There is some evidence that feedback effects may modify the Schmidt law at scales below 1 kpc.

Purpose:Recently we found that the early onset of regular tobacco use is as predictive of lifetime drug use and depressive disorders as it is of alcohol use disorders [Alcohol.: Clin. Exp. Res. 23 (1999) 513.]. This finding, which paralleled findings regarding early onset of alcohol use [J. Subst. Abuse 10 (1998) 59.], suggested that early regular use of any drug might simply be an indicator of risk for a constellation of problem behaviors. The purpose of the present study is to test this hypothesis as well as to study the strength and patterns of associations among these problem behaviors already present among youth. The results will permit description of more precise profiles to identify groups of children at risk. Methods:Using data for respondents aged 12–16 from the Third National Health and Nutrition Examination Survey (NHANES III), descriptive statistics were calculated and logistic regression models were estimated. Results:Descriptive analyses indicated that in comparison with those who never smoked, or who simply experimented, early-onset regular smokers, both those who began at age 13 or younger and those who did so between 14 and 16, were those most likely to use alcohol and other drugs as well as have school problems and early sexual experiences culminating in pregnancy. Multivariate logistic regression analyses were conducted to assess the associations among these high-risk behaviors. Implications:These results support the hypothesis that early onset of smoking is but an indicator of a syndrome of problem behaviors already in place during childhood. They also suggest that the significance of an age onset variable may differ depending on the age of the sample used. As follow-up data are collected, we expect to learn much about the natural course of the distinct risk groups identified in the analyses by studying longitudinally this nationally representative group of early adolescents.

We have identified 1057 globular cluster candidates in a WFPC2 image of the inner region of M87. The globular cluster luminosity function (GCLF) can be well fitted by a Gaussian profile with a mean value of m0V=23.67+-0.07 mag and s=1.39+-0.06 mag. The GCLF in five radial bins is found to be statistically the same at all points, showing no clear evidence of dynamical destruction processes based on the luminosity function (LF). Similarly, there is no obvious trend between the half-light radius of the clusters and the galactocentric distance. The core radius of the globular cluster density distribution is Rc=56'', considerably larger than the core of the stellar component (Rc=6.''8). The mean color of the cluster candidates is V-I=1.09 mag, which corresponds to an average metallicity of Fe/H=-0.74 dex. The color distribution is bimodal everywhere, with a blue peak at V-I=0.95 mag and a red peak at V-I=1.20 mag. The red population is only 0.1 mag bluer than the underlying galaxy, indicating that these clusters formed late in the metal-enrichment history of the galaxy and were possibly created in a burst of star/cluster formation 3-6 Gyr after the blue population. We also find that both the red and the blue cluster distributions have a more elliptical shape (Hubble type E3.5) than the nearly spherical galaxy. The average half-light radius of the clusters is [?]2.5 pc, which is comparable to the 3 pc average effective radius of the Milky Way clusters, although the red clusters are [?]20% smaller than the blue ones.

The kinetics of salt release from simulated saline sediments was studied to ascertain the potential of sediments as a diffuse source of salinity. Two rate equations were derived, both based on the premise that dissolution was a diffusion controlled process. The equations were ln (1 − C/Cs) = ‐ktand C= k′t1/2, where cis the concentration at any point in the bulk solution, csis the equilibrium concentration of the soluble soil minerals, tis time, kis the first‐order rate constant, and k′ a proportionality constant. Kinetic data were obtained from a saline typic torriorthent soil derived from Mancos shale in the Price river Basin, Utah. During the initial 72 hours of reaction, dissolution can be described by three, diffusion controlled, reactions. Increasing particle size decreased the rate of reaction. Both derived equations were equally effective in describing salt release.

AbstractImpacts of Bacillus thuringiensisvar. kurstaki(Btk) and defoliation by gypsy moth [Lymantria dispar(L.)] on native, non-target arthropods were evaluated in eastern West Virginia from 1990 to 1992. Adult and larval arthropods were collected by foliage sampling and light-trapping at 24 20-ha (50-acre) plots, representing six replicates of four treatments: unsprayed, gypsy moth absent (control); unsprayed, gypsy moth present (defoliation); sprayed, gypsy moth absent; and sprayed, gypsy moth present. Pre-treatment data were collected in 1990. In May 1991, one application of Btkwas made to 12 plots at a dosage of 14.4 BIU/ha (36 BIU/acre). Post-treatment data were collected in 1991 and 1992. With few exceptions, detectable effects from Btkapplication were restricted to Lepidoptera. Although abundance and species richness of larval and adult non-target Lepidoptera decreased at all plots between 1990 and 1992, abundance and species richness were reduced at Btk-treated plots relative to untreated plots. Richness and abundance of some larval and adult Lepidoptera declined at defoliation plots. Although the short-term (< 1 year) impacts of Btkapplication on non-target Lepidoptera are negative, the long-term effects (> 1 year) of reduced abundance of gypsy moth larvae may be beneficial for some native species. Although Btkapplication and defoliation reduce abundance of native Lepidoptera, environmental conditions such as weather may have a greater influence on population fluctuations.

AbstractEffects of an operational application of Dimilin®on non-target insects were evaluated in eastern West Virginia in 1988 and 1989. Dimilin was applied in 1988 (70,75 g AI per ha). Insects were collected by light-traps at seven pairs of Dimilin-treated and control sites. Lepidoptera experienced the greatest impact, displaying reduced abundance and species richness at treated sites. No effects were observed among Coleoptera, Diptera, or Hymenoptera.

The main fields of research in tropical rain forest ecology today are briefly described and the development of the subject over the past forty years is outlined.

This first study of the whole genusAgathis makes use of recent local revisions of the New Caledonian and Australian species which are all maintained. The male cone is shown to have most of the taxonomically useful variation, and this confirms the findings of two partial revisions centred on Indonesian species. Thirteen species are recognized, two of which have two subspecies. New Caledonia has five, and Australia three, sympatric species. Otherwise the species are allopatric except for a few populations of central MalesianA. dammara within the range of west MalesianA. borneensis. One of these montane populations is the distinctiveA. dammara subsp.flavescens of Malaya, formerly a full species.

Rotation curves of spiral galaxies in clusters are compared with their counterparts in the field using three criteria: (1) inner and outer velocity gradients, (2)M/L gradients, and (3) Burstein's mass type methodology. Both Ha emission-line rotation curves and more extendedHi rotation curves are used. A good correlation is found between the outer gradient of the rotation curve and the galaxy's distance from the centre of the cluster, in the sense that the inner galaxies tend to have falling rotation curves while the outer galaxies, and field galaxies, tend to have flat or rising rotation curves. A correlation is also found between theM/L gradient across a galaxy and the galaxy's position in the cluster, with the outer galaxies having steeperM/L gradients. Mass types for field spirals are shown to be a function of both Hubble-type and luminosity, contrary to earlier results. The statistical difference between the distribution of mass types in clusters and in the field reported by Bursteinet al. is confirmed. These correlations indicate that the inner cluster environment can strip away some fraction of the mass in the outer halo of a spiral galaxy, or alternatively, may not allow the halo to form.

We have determined the origin and cell surface phenotype of B cells producing antibody in response to immunization with the non-self TI-2 antigen polyvinyl pyrrolidinone (PVP). We report that the responding cells are derived from precursors in adult bone marrow and display the phenotype characteristic of B-1 cells. By use of allotype marked chimeric mice, constructed by reconstituting lethally irradiated recipients with adult bone marrow and peritoneal B-1 lymphocytes of recognizably different Ig allotypes, immunized with 1 microgram PVP, we found that although a substantial part of the total IgM produced in these chimeras bore the allotype of the transferred peritoneal B-1 cells, essentially all of the anti-PVP IgM expressed the allotype of the adult bone marrow. Fifteen of 16 hybridomas derived from a normal PVP-immune adult mouse bore N nucleotides at the V-D and D-J junctions of their heavy chain CDR3 regions, indicating their origin from precursors in the adult bone marrow. By use of ELISA spot analysis, we found the cells responding to PVP to be localized in the spleens of normal immunized mice. We then used multiparameter flow cytometric sorting to determine the cell surface phenotype of these cells. We found that the cells producing anti-PVP were greatly enriched in a small subpopulation with the phenotypic characteristics of B-1 cells; they were B220intermediate, CD5low, IgMhigh, IgDlow, CD43+ and CD23-. This subpopulation was also enriched for all cells producing IgM, regardless of specificity (the so-called 'spontaneous' antibody). We conclude that the B-1 phenotype is more likely a marker for a state of differentiation than for a discrete lineage of B cells.

The species richness of tropical rain forests creates difficulties for ecological analysis. It may usefully be simplified by defining ecological species groups whose members share characteristics of importance for determining forest structure and composition. Many such classifications have been published, but few are properly explained. The terminology is confused from lack of precise definitions. We propose a simple division of tree species into two groups or guilds, pioneer and non-pioneer (or climax), based on seed germination and seedling establishment. Within each guild there is continuous variation and we recommend arbitrary subdivision by height at maturity. We believe this classification to be applicable in all tropical rain forests.

Silicon substrate slices in (111) or (001) surface orientation have been machined in two ways: precision ground by a diamond abrasive wheel to a surface roughness Ra ≈ 11 nm, or turned on a highly stiff single-point diamond turning machine to Ra,≈0·5 nm. Transmission electron microscopy of cross-sections of the machined surfaces has established the following.The mean depth of permanent damage in both cases lies in the range 100-400 nm. In the ground specimens the damage depth is very variable, and the damage consists of regions of well defined dislocation loops on several slip systems, other regions with a very high density of irregular dislocation arrays, and occasional microcracks up to 500nm deep which do not always intersect the surfaces. Patches of amorphous silicon are also observed. Beneath the turned surfaces the damage appears more homogeneous, consisting of dislocation loops predominantly on a single slip system in any given region of the specimen.

AbstractThe performance of unbaited emergence traps and attractant-baited pitfall and flight traps was compared on the basis of suitability to produce population indices for two beetles, Steremnius carinatus(Boheman) and Hylastes nigrinus(Mannerheim), colonizing roots of Douglas fir in northern California. These beetles transmit Ceratocystis wageneriGoheen and Cobb, the fungus causing black stain root disease in Douglas fir. Trap sites were near stumps along transect lines through recently logged areas. Pitfall traps were judged the most promising for both species based on their relatively high catches and low expense. Although catch by emergence traps was low for both species, they appeared to catch the majority of S. carinatus. For both species, pitfall trap catches varied with date, study area, trapping line within study area, and stump within line. A number of variables, such as diameter of stump or type of ground cover, were significantly correlated with trap catch, and made significant contributions to linear models with catch as the dependent variable. Differences between study areas in the effect of variables on catch, and the possibility that pitfall trapping is subject to artifacts, suggested that the results of pitfall trapping need to be carefully scrutinized if they are to be used as a population index.

Studies with congenic resistant strains of mice indicate that susceptibility to Rous sarcoma virus tumorigenesis is influenced by a gene or genes associated with the major histocompatibility complex (H-2). These genes manifest dominant relative susceptibility. Preliminary studies indicate that the CBA/J strain harbors a gene or genes for relative susceptibility, which are recessive. These results are compared with other studies onH-2-associated genes affecting murine viral oncogenesis.

In this paper, an analytical model is developed for computation of the temperature distribution in a hollow cylindrical workpiece during machining with a single point tool. Such a model is useful for prediction of machined surface error arising from thermal expansion of the workpiece during machining. The model considers the interface between the tool and the workpiece to be a helically moving volumetric heat source. The governing equation satisfied by the temperature field, along with the appropriate boundary and initial conditions, is solved using the method of integral transforms. The experimental test facility used for the conduct of experiments for measurement of the temperature response in a cylindrical workpiece, namely a cylinder bore, during machining is discussed. The results from tests conducted using a laser as a heat source to verify the analytical model for temperature field are then presented. Several cylinder boring tests have been conducted, and the results from these tests along with the analysis performed with the temperature data to calibrate the temperature model are then discussed. Comparisons between predicted and measured temperature response in a cylinder bore during machining show good agreement.

The susceptibility of six spiroplasma strains to heavy-metal salt was characterized in terms of minimal inhibitory concentrations and minimal biocidal concentrations in broth tube dilution tests. The strains were most susceptible to mercuric chloride and silver nitrate; less susceptible to copper sulfate, cobalt chloride, lead nitrate, and cadmium sulfate; and least susceptible to nickel chloride and zinc sulfate. Spiroplasma citri strains Maroc R8A2 and C189 were the most susceptible to five of eight heavy-metal salts, and honeybee spiroplasma strain AS576 and Spiroplasma floricola strain 23-6 were generally the least susceptible. The difference between the minimal biocidal concentrations and the minimal inhibitory concentrations was greater for certain heavy-metal salts than for others.

The presence of Miocene mammals of North American affinity in the Panama Canal Zone indicates that Central America was attached to North America. That this attachment was a broad and stable land mass is shown by the close relation of the Panama Miocene herbivores to the widely distributed Miocene herbivore fauna of North America. A continuous connection existed probably throughout the Tertiary, to the west and north of the isthmian region, but the tectonically active isthmus probably was broken up into an archipelago during most of Tertiary time. Between the islands ran the Strait of Panama; from time to time parts of the isthmian area were connected to the stable land to the west, allowing eastward migration of land animals. The mammals of North American affinity in the Cucaracha Formation were found only a few kilometers from the western end of the San Blas Area, a stable land mass in eastern Panama that was separated from South America by the Bolivar Trough during most of the interval between Oligocene and Pliocene time. The Strait of Panama was a less stable barrier than the Bolivar Trough; this being so, it is likely that the San Blas Area was inhabited by land animals of North American rather than South American affinity. Thus, the disappearance of the Bolivar seaway in Pliocene time would have allowed, probably for the first time, mingling of the North and South American mammal faunas.