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The primary structural component of the bacterial cell wall is peptidoglycan, which is essential for viability and the synthesis of which is the target for crucial antibiotics1,2. Peptidoglycan is a single macromolecule made of glycan chains crosslinked by peptide side branches that surrounds the cell, acting as a constraint to internal turgor1,3. In Gram-positive bacteria, peptidoglycan is tens of nanometres thick, generally portrayed as a homogeneous structure that provides mechanical strength4–6. Here we applied atomic force microscopy7–12 to interrogate the morphologically distinct Staphylococcus aureus and Bacillus subtilis species, using live cells and purified peptidoglycan. The mature surface of live cells is characterized by a landscape of large (up to 60 nm in diameter), deep (up to 23 nm) pores constituting a disordered gel of peptidoglycan. The inner peptidoglycan surface, consisting of more nascent material, is much denser, with glycan strand spacing typically less than 7 nm. The inner surface architecture is location dependent; the cylinder of B. subtilis has dense circumferential orientation, while in S. aureus and division septa for both species, peptidoglycan is dense but randomly oriented. Revealing the molecular architecture of the cell envelope frames our understanding of its mechanical properties and role as the environmental interface13,14, providing information complementary to traditional structural biology approaches. Using high-resolution atomic force microscopy of live cells, the authors present an updated view of the cell walls of both Staphylococcus aureus and Bacillus subtilis. [ABSTRACT FROM AUTHOR]

This review compiles, summarizes and provides new analytical insights on large amounts of fragmented information on the diets and feeding behaviours of syngnathids (Family Syngnathidae). This review is broken down into two distinct sections that address two central questions: (1) How, where, when and what do syngnathids eat? And (2) How does diet differ with feeding morphology? For (1) we summarized both qualitative and quantitative information on the diets and feeding behaviours of syngnathids found in the published and grey literature. This section includes a narrative summary of syngnathid feeding events and foraging behaviours (e.g. body mechanics and feeding morphologies, habitat use, seasonal and diurnal timing of feeding, energetics) and a tabulated summary of what syngnathids eat. For (2) we performed a comparative analysis on the diets of 41 species of syngnathid, comprising 15 genera from 39 sources in peer-reviewed and grey literature. Redundancy analyses on bulk, numeric, and frequency of occurrence data, analyzed separately, all show large unexplained dietary variation, which we hypothesize is the result of large differences in prey availability. Of the explained variation, syngnathid diets were most strongly correlated with head characteristics: most notably relative snout lengths and gape sizes. Syngnathid feeding morphologies also showed high phylogenetic signal; this suggests that dietary differences across genera were largely explained by how syngnathids differed with respect to these feeding morphologies. This review identifies new taxonomic patterns, and expands on previous generalities, improving our ecological understanding of this diverse group of fishes. [ABSTRACT FROM AUTHOR]

Many vulnerable marine species are caught in small-scale fisheries that lack long-term records, thereby limiting the development of effective evidence-based management measures. To uncover recent trends in fish landings and value in the absence of historical data, we interviewed 77 fishers and five buyers on Phu Quoc Island in Southern Vietnam regarding their current and past fishing practices, with a focus on seahorse catches. Seahorses (Hippocampus spp.) are caught using multiple gear types (including trawls, crab nets, and compressor diving) and have both cultural and financial value. Most fishers catch seahorses incidentally, though 14 targeted them and made the majority of their income from their sale. Fishers reported that seahorse catch rates decreased by 86–95% from 2004 to 2014, while landed value simultaneously increased by 534%. If these reports are accurate, seahorse fishing on Phu Quoc is unsustainable and requires immediate management controls. [ABSTRACT FROM AUTHOR]

Moths form an important part of Scotland's biodiversity and an up-to-date assessment of their status is needed given their value as a diverse and species-rich taxon, with various ecosystem roles, and the known decline of moths within Britain. We use long-term citizen-science data to produce species-level trends and multi-species indicators for moths in Scotland, to assess population (abundance) and distribution (occupancy) changes. Abundance trends for moths in Scotland are produced using Rothamsted Insect Survey count data, and, for the first time, occupancy models are used to estimate occupancy trends for moths in Scotland, using opportunistic records from the National Moth Recording Scheme. Species-level trends are combined to produce abundance and occupancy indicators. The associated uncertainty is estimated using a parametric bootstrap approach, and comparisons are made with alternative published approaches. Overall moth abundance (based on 176 species) in Scotland decreased by 20% for 1975–2014 and by 46% for 1990–2014. The occupancy indicator (based on 230 species) showed a 16% increase for 1990–2014. Alternative methods produced similar indicators and conclusions, suggesting robustness of the results, although rare species may be under-represented in our analyses. Species abundance and occupancy trends were not clearly correlated; in particular species with negative population trends showed varied occupancy responses. Further research into the drivers of moth population changes is required, but increasing occupancy is likely to be driven by a warming summer climate facilitating range expansion, whereas population declines may be driven by reductions in habitat quality, changes in land management practices and warmer, wetter winters. [ABSTRACT FROM AUTHOR]

Exploitation for trade is one of the biggest threats to many species, especially for marine fishes. Trade regulations should, therefore, be effective in helping conserve marine fish populations. The Convention of International Trade in Endangered Species of Wild Fauna and Flora (CITES), one of the few multilateral environmental agreements with enforcement capacity, has embraced a number of marine fishes in recent years. However, the impacts of such measures on wildlife trade have rarely been assessed. We conducted a case study of the dried seahorse (Hippocampus spp.) trade in Thailand to understand the trade of these species under CITES regulations. We carried out 203 semi-structured interviews with traders to estimate the economic scale of Thai seahorse trade, and compared perceived changes with official trade datasets. Even though most seahorses were incidentally caught, we estimated that dried seahorses could be worth US$26.5 million per year for Thai fishers. However, the total declared annual export value was only around US$5.5 million, and had decreased to US$1 million in 2013. Considering the economic value of seahorses, the large discrepancy between declared export volumes and catch estimates suggested that trade may be underreported. While official data shows the export volume decreased after the implementation of CITES listing in 2005, our respondents did not report a similar trend. In contrast, the prices of seahorses were reported to be increasing. Our study highlights the economic importance of marine fishes captured as bycatch and the importance of international and domestic management measures for the trade of bycatch species. [ABSTRACT FROM AUTHOR]

Components made by laser powder bed fusion (L-PBF) additive processes require extensive trial and error optimization to minimize defects and arrive at targeted microstructure and properties. In this work, in situ infrared thermography and ex situ surface roughness measurements were explored as methodologies to ensure Inconel® 718-part quality. For a given laser energy of 200 Watts, prismatic samples were produced with different exposure times (80 to 110 µs) and point spacings (80 to 110 µm). The infrared intensities from laser-material interaction zones were measured spatially and temporally. The conditions leading to higher IR intensity and lowest surface roughness values correlated well with less porosity and coarse solidification grain structure. The transition from highly columnar to misoriented growth is attributed to changes in thermal gradients and liquid-solid interface velocities. Hardness measurements and electron microscopy of the as-processed and post-processed heat-treated samples show complex transitions in microstructural states including the heavily dislocated FCC matrix, reduction of dislocation density, and copious precipitation, respectively. These results show that the geometry-process-structure-property correlations are dynamic, and they cascade depending on the transitions of phase states from powder to liquid to solid, as well as phase decompositions and deformations within the solid FCC phase. Validity of using analytical weld process models to describe the above phenomena is also highlighted. [ABSTRACT FROM AUTHOR]

Innovative designs for turbines can be achieved by advances in nickel-based superalloys and manufacturing methods, including the adoption of additive manufacturing. In this regard, selective electron beam melting (SEBM) and selective laser melting (SLM) of nickel-based superalloys do provide distinct advantages. Furthermore, the direct energy deposition (DED) processes can be used for repair and reclamation of nickel alloy components. The current paper explores opportunities for innovation and qualification challenges with respect to deployment of AM as a disruptive manufacturing technology. In the first part of the paper, fundamental correlations of processing parameters to defect tendency and microstructure evolution will be explored using DED process. In the second part of the paper, opportunities for innovation in terms of site-specific control of microstructure during processing will be discussed. In the third part of the paper, challenges in qualification of AM parts for service will be discussed and potential methods to alleviate these issues through in situ process monitoring, and big data analytics are proposed. [ABSTRACT FROM AUTHOR]

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The main purpose of this research is to study the time dependent behaviour of a geopolymer concrete. The geopolymer binder is composed of 85.2 % of low calcium fly ash and only 14.8 % of ground granulated blast furnace slag. Both drying shrinkage and creep are studied. In addition, different curing conditions at elevated temperature were used. All experimental results were compared to predictions made using the Eurocode 2. The curing regime plays an important role in the magnitude and development of both creep and drying shrinkage of class F fly ash based geopolymer concrete. A minimum of 3 days at 40 °C or 1 day at 80 °C is required to obtain final drying shrinkage strains similar to or less than those adopted by Eurocode 2 for ordinary Portland cement (OPC) concrete. Creep strains were similar or less than those predicted by Eurocode 2 for OPC concrete when the geopolymer concrete was cured for 3 days at 40 °C. After 7 days at 80 °C, creep strains became negligible. [ABSTRACT FROM AUTHOR]

Phenotypic plasticity can influence evolutionary change in a lineage, ranging from facilitation of population persistence in a novel environment to directing the patterns of evolutionary change. As the specific nature of plasticity can impact evolutionary consequences, it is essential to consider how plasticity is manifested if we are to understand the contribution of plasticity to phenotypic evolution. Most morphological traits are developmentally plastic, irreversible, and generally considered to be costly, at least when the resultant phenotype is mis-matched to the environment. At the other extreme, behavioral phenotypes are typically activational (modifiable on very short time scales), and not immediately costly as they are produced by constitutive neural networks. Although patterns of morphological and behavioral plasticity are often compared, patterns of plasticity of life history phenotypes are rarely considered. Here we review patterns of plasticity in these trait categories within and among populations, comprising the adaptive radiation of the threespine stickleback fish Gasterosteus aculeatus. We immediately found it necessary to consider the possibility of iterated development, the concept that behavioral and life history trajectories can be repeatedly reset on activational (usually behavior) or developmental (usually life history) time frames, offering fine tuning of the response to environmental context. Morphology in stickleback is primarily reset only in that developmental trajectories can be altered as environments change over the course of development. As anticipated, the boundaries between the trait categories are not clear and are likely to be linked by shared, underlying physiological and genetic systems. [ABSTRACT FROM AUTHOR]

The postglacial adaptive radiation of the threespine stickleback fish (Gasterosteus aculeatus) has been widely used to investigate the roles of both adaptive evolution and plasticity in behavioral and morphological divergence from the ancestral condition represented by present-day oceanic stickleback. These phenotypes tend to exhibit high levels of ecotypic differentiation. Population divergence in life history has also been well studied, but in contrast to behavior and morphology, the extent and importance of plasticity has been much less well studied. In this review, we summarize what is known about life-history plasticity in female threespine stickleback, considering four traits intimately associated with reproductive output: age/size at maturation, level of reproductive effort, egg size and clutch size. We envision life-history plasticity in an iterative, ontogenetic framework, in which females may express plasticity repeatedly across each of several time frames. We contrast the results of laboratory and field studies because, for most traits, these approaches give somewhat different answers. We provide ideas on what the cues might be for observed plasticity in each trait and, when possible, we inquire about the relative costs and benefits to expressed plasticity. We end with an example of how we think plasticity may play out in stickleback life history given what we know of plasticity in the ancestor. [ABSTRACT FROM AUTHOR]

Summary: The study investigated the real-world relationship between teriparatide adherence and persistence and fracture outcomes in a US claims database. Fracture risk was estimated to decrease as adherence and persistence increased for any clinical, vertebral, and non-vertebral fractures. Greater emphasis on programs to increase patient adherence may improve clinical outcomes. Introduction: Adherence to osteoporosis treatment is essential for achieving optimal therapeutic outcomes. Previous findings from clinical trials and observational studies demonstrate that longer teriparatide (TPTD) exposure is associated with fewer fractures. The study aim was to investigate real-world relationships between TPTD adherence and persistence and fracture outcomes. Methods: The Thomson Reuters MarketScan® database, 2004-2008, was used to identify TPTD users with continuous enrollment 12 months pre- and 24 months post-TPTD initiation. Post-index fractures included vertebral and non-vertebral. Adherence (medication possession ratio, MPR) groups were defined as high (MPR ≥ 0.80), medium (0.5 ≤ MPR < 0.8), and low (MPR < 0.5). Persistence groups were defined by periods 1-6, 7-12, 13-18, and 19-24 months. Logistic regressions modeled fracture risk for any clinical, hip, vertebral, and non-vertebral fractures, controlling for patient characteristics, insurance and healthcare provider types, Charlson comorbidity index, bone mineral density screening, medication use, and fracture history. Results: Among 3,587 TPTD patients (mean age 68.9 years; 91% female), fracture risk was lowest in high MPR patients in all models except hip (OR = 1.17; p = 0.64). Medium versus high MPR was a significant risk factor for any fracture (OR = 1.49; p = 0.004) and non-vertebral fracture (OR = 1.45; p = 0.014); low-MPR was a significant risk factor for any fracture (OR = 1.64; p < 0.01), vertebral fracture (OR = 2.56; p = 0.001), and non-vertebral fracture (OR = 1.44; p = 0.013). Persistence of 1-6 months versus 19-24 months was associated with higher risk for any clinical (OR = 1.88, p < 0.001), vertebral (OR = 3.69; p < 0.001), and non-vertebral fracture (OR = 1.51; p = 0.011), but not hip (OR = 1.93; p = 0.08). Conclusions: Fracture risk decreased as TPTD adherence and persistence increased for any clinical, vertebral, and non-vertebral fractures. [ABSTRACT FROM AUTHOR]

Summary: Adherence to, and persistence with, treatments for osteoporosis are low. Adherence with teriparatide decreases over time. Higher copayments in the commercial/Medicare population were associated with worse persistence. Understanding factors such as prior screening, prior treatment history, and out of pocket costs that influence persistence with teriparatide may help clinicians make informed decisions. Introduction: The purpose of this study was to evaluate adherence and persistence with teriparatide. Methods: Beneficiaries with at least one claim for teriparatide in 2003 or 2004 and continuous enrollment in the previous 12 months and subsequent 6 months were identified in a national commercial/Medicare and Medicaid administrative claims database (MarketScan®). Adherence was assessed through calculation of the medication possession ratio (MPR). Persistence was measured by time until discontinuation and time until first 60-day gap in treatment. Factors associated with persistence were assessed using Cox proportional hazards models. Results: The average MPR at 6 months was 0.74 ( N = 2,218) and at 12 months, was 0.66 ( N = 1,303). At 6 months, 64.6% of patients remained on therapy and at 12 months, 56.7% remained. Bone mineral density screening and use of antiresorptive therapy within the 12 months pre-period, and lower patient copayments were associated with increased persistence. Conclusion: Patients appear to have good adherence with teriparatide over the first 6 months which declines over time. Prior screening and treatment of osteoporosis and out of pocket costs appear to impact persistence. To optimize patient outcomes, clinicians should consider clinical factors that impact persistence, while healthcare decision makers should consider the negative effect of higher patient copayments on persistence. [ABSTRACT FROM AUTHOR]

The demographic and clinical characteristics of patients initiating teriparatide were compared with those of patients initiating bisphosphonates for the treatment of osteoporosis. In these samples of commercially insured, Medicare, and Medicaid patients, patients initiating teriparatide were older, in poorer health, and appeared to have more severe osteoporosis than patients initiating bisphosphonates. The demographic and clinical characteristics of patients initiating teriparatide are compared with those of patients initiating bisphosphonates. Beneficiaries (45 years and older) with at least one claim for teriparatide or a bisphosphonate from 2003 to 2005 and continuous enrollment in the previous 12 months and subsequent 6 months were identified from commercial, Medicare, and Medicaid administrative claims databases. Patients initiating teriparatide (commercial/Medicare ( N = 2,218); Medicaid ( N = 824)) were compared to patients initiating bisphosphonates (commercial/Medicare ( N = 97,570); Medicaid ( N = 77,526)) in terms of age, provider specialty, comorbidities, prior use of osteoporosis medications, fractures, BMD screening, health status, and resource utilization. Teriparatide patients were older and in poorer health than bisphosphonate patients. Approximately 38% of teriparatide patients in both groups had fractured in the pre-period compared to 16% of commercial/Medicare and 15% of Medicaid bisphosphonate patients. Teriparatide patients were more likely to have used osteoporosis medications in the pre-period (79.9% versus 32.1% (commercial/Medicare); 82.2% versus 19.6% (Medicaid)). In these samples of patients, those initiating teriparatide differed from those initiating bisphosphonates. Teriparatide patients were older, in poorer health, and appeared to have more severe osteoporosis than bisphosphonate patients. Comparisons of treatment outcomes should take these differences in patient characteristics into consideration. [ABSTRACT FROM AUTHOR]

Sorghum ergot, caused by Claviceps africana, has remained a major disease problem in Australia since it was first recorded in 1996, and is the focus of a range of biological and integrated management research. Artificial inoculation using conidial suspensions is an important tool in this research. Ergot infection is greatly influenced by environmental factors, so it is important to reduce controllable sources of variation such as inoculum concentration. The use of optical density was tested as a method of quantifying conidial suspensions of C. africana, as an alternative to haemocytometer counts. This method was found to be accurate and time efficient, with possible applications in other disease systems. [ABSTRACT FROM AUTHOR]

Reliable measurements of pollutant levels in the vicinity of a toll plaza appear to be rare. In order to assess the exposure of toll booth operators to carbon monoxide, a continuous carbon monoxide monitor was installed at head height in the booth of a medium density traffic lane at the Mariannhill toll plaza, situated on a busy highway near Durban, South Africa. Measurements in excess of 500 ppmv were recorded and the high daily mean carbon monoxide concentrations may account for some of the symptoms such as headaches and general malaise that have been reported by workers in the booths. Generally, carbon monoxide levels recorded far exceed the recommended limit set by the South African authorities. These results have led to recommendations regarding the structure of new and existing toll booths to minimize the exposure of toll booth workers to adverse effects of vehicle-emitted pollutants. [ABSTRACT FROM AUTHOR]

We show that single-point mutations conferring target-site resistance (kdr) to pyrethroids and DDT in aphids and houseflies, and gene amplification conferring metabolic resistance (carboxylesterase) to organophosphates and carbamates in aphids, can have deleterious pleiotropic effects on fitness. Behavioural studies on peach-potato aphids showed that a reduced response to alarm pheromone was associated with both gene amplification and the kdr target-site mutation. In this species, gene amplification was also associated with a decreased propensity to move from senescing leaves to fresh leaves at low temperature. Housefly genotypes possessing the identical kdr mutation were also shown to exhibit behavioural differences in comparison with susceptible insects. In this species, resistant individuals showed no positional preference along a temperature gradient while susceptible genotypes exhibited a strong preference for warmer temperatures. [ABSTRACT FROM AUTHOR]

The plasma levels of procalcitonin (PCT) are increased in patients with severe bacterial infections. Its cellular origin and potential pathophysiological function in sepsis is, however, unclear. White blood cells have recently been described to express both PCT mRNA and protein. The aim of this study was to determine whether PCT has any influence on the surface expression of receptors, relevant in inflammation, on human whole blood leukocytes under normal and septic conditions. Venous blood from healthy donors was incubated with PCT (40 ng/ml or 1200 ng/ml) alone or in combination with lipopolysaccharide (LPS, 10 ng/ml) or peptidoglycan (PepG, 10 micrograms/ml) for 6 h. The surface expression of CD14, CD54, CD64, CD80, CD86 and HLA-DR was determined by flow cytometry. We could not detect any influence of PCT on the expression of these receptors. Further studies on potential effects on other cell types during infection seem warranted. [ABSTRACT FROM AUTHOR]

The female-produced sex pheromone of the New Zealand raspberry budmoth, Heterocrossa rubophaga, was investigated. Gas chromatographic–mass spectrometric analyses revealed the ketone, ( Z)-12–nonadecen9–one (Z12–19–9–one). This compound had previously been found in extracts of the sex pheromone gland of the only other carposine moth for which a sex pheromone has been identified, Carposina niponensis, although its effect on the behavior of C. niponensis males had not been established. Field trapping trials in berry fruit gardens showed this compound to elicit high catches of male H. rubophaga, with the catch appearing to plateau (and perhaps decrease) above a dosage of 300 μg on a red rubber septum. In an analysis of an extract of female H. rubophaga sex pheromone glands, there was a suggestion that the homologous ( Z)-7–eicosen-11–one, the known sex pheromone component of C. niponensis, was also present. However this could not be established unequivocally and, in a field trial, addition of a small amount of this compound to Z12–19–9–one resulted in no significant increase in trap catch relative to traps baited with Z12–19–9–one alone. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports published within the issue on topics including plasticity across ontogeny, plasticity and individual variation, and life history plasticity in threespine sticklebacks.

When introduced into a wind tunnel with low windspeeds (0.2–0.3 m/sec), neonate E. postvittana larvae were more likely to walk in a downwind rather than upwind direction. This tendency to walk downwind did not change when odors from apple leaves or fruit were introduced into the wind tunnel. In a second assay that measured travel times of larvae as they walked from the center to the edge of filter paper disks, larvae moved more slowly on disks treated with extracts of apple leaves or extracts of apple fruit, but did not slow their movement on disks treated with extracts of a nonhost, Coprosma repens. Analysis of videorecords revealed that larvae on disks treated with a dichloromethane extract of apple leaves took more circuitous routes, walked more slowly, and stopped more frequently than larvae walking on solvent-treated disks. When the dosage of this dichloromethane apple leaf extract was increased or when larvae were held without food prior to testing, differences between travel times on solvent- and extract-treated disks did not increase significantly. The dichloromethane apple leaf extract, when tested in the wind tunnel with low windspeeds, also caused larvae to delay spinning down on a silken thread after reaching the edge of the disk, but had no effect on spin-down times when tested in still-air conditions. Testing of rotary evaporated apple leaf extracts and fractionation of these extracts indicated that a number of both volatile and relatively involatile chemicals contribute to the behavioral responses of E. postvittana larvae. [ABSTRACT FROM AUTHOR]

The accessory gene regulator ( agr) and staphylococcal accessory regulator ( sar) loci are important regulators of toxin production in Staphylococcus aureus. In this study we examined how environmental conditions – degree of aeration and salt concentration – affect the transcription and translation of mRNAs for α- haemolysin (Hla) and serine protease (Ssp) via these pathways and influence the stability of these proteins. Using Northern analysis, we have confirmed earlier observations that sarA is involved in the upregulation of RNAIII, the effector molecule encoded by the agr locus. However, this effect was abolished in highly aerated cultures. While sarA does appear to have an up-regulatory effect on hla transcription that is independent of agr, we propose that the PC1839 ( sarA) mutant produces less α-haemolysin activity mainly as a result of post-translational inactivation by proteases. The most obvious phenotypic feature of PC1839 ( sarA) is the upregulation of proteases. In this study we show that ssp is repressed by SarA at the transcriptional level. Western analysis using an anti-α-haemolysin antibody identified a major breakdown product that is only present in the supernatant of strains that are overexpressing serine protease. We have also confirmed that agr exerts a significant regulatory influence on hla at the level of translation, as well as transcription. Finally, the addition of salt upregulates ssp transcription and dramatically downregulates transcription of hla, and is an example of an environmental parameter that affects toxin production independently of agr and sarA. How environmental signals are transduced to control α-haemolysin and serine protease production, activity and stability at multiple levels are discussed. [ABSTRACT FROM AUTHOR]

Fatty acyl moieties present in the female sex pheromone gland of the lightbrown apple moth, Epiphyas postvittana, include the analogues of the two sex pheromone components, ( E)-11-tetradecenyl acetate and ( E,E)-9,11-tetradecadienyl acetate. Application of deuterium-labelled fatty acids followed by analysis by gas chromatographymass spectrometry showed that biosynthesis of the two pheromone components involved initial Δ11-desaturation of myristic and palmitic acids respectively. [ABSTRACT FROM AUTHOR]

The stylets of Nilapavarta lugens consist of two maxillae that interlock to form separate food and salivary ducts partially surrounded by two mandibles. The ultrastructure of the sensory innervation of the stylets is described. Each maxilla possesses five neurones which extend to the tip of the stylet. The mandibles also contain five neurones, four of which are paired. The paired neurones comprise a shorter dendrite extending part of the way along the stylet and a longer one extending to the tip. The possible functions of these neurones are discussed. Gustatory receptors are located in the small passageway leading from the food duct to the cibarium. The receptors are in two distinct groups on the epipharyngeal side and one group on the hypopharyngeal side of the food canal. Two to five neurones innervate each receptor which connects to the food canal via a small pore. [ABSTRACT FROM AUTHOR]

The ultrastructure of the sensory receptors located on the labium of the rice brown planthopper is described; possible functions of individual receptors are suggested on morphological grounds. Uniporous chemosensilla which may or may not possess a mechanoreceptive dendrite, domed multiporous chemosensilla, and mechanoreceptive pegs are present on the flattened labial tip. Mechanoreceptive pegs are distributed over the labium. The fine structure of a multilobed sensillum located on either side of the labium is also described. [ABSTRACT FROM AUTHOR]

Stimuli from the plant Camellia japonica that influence the host-finding and acceptance behaviors of adult females of the generalist herbivore Epiphyas postvittana were investigated. In a binary choice test in a small (35-cm-diam.) arena, females discriminated between a plant and a laminated card model, laying many more eggs on the plant. Observations of females showed that the greater number of eggs laid on the plant were primarily due to on-plant behaviors, with females spending significantly more time per visit on the plant than on the model. Interestingly, females landed a similar number of times on the plant as on the model, suggesting that volatile chemicals from the plant did not influence host-finding. This observation was further supported by wind-tunnel studies, in which females showed little or no upwind flight activity in response to plants and laid similar numbers of eggs on upwind and downwind plants. Leaf surface texture, a combination of smoothness and fine structure (consisting of the midvein and other raised leaf veins), was found to stimulate egg laying by females. Methanol, dichloromethane, and pentane extracts were made of the waxes on the leaf surface. Of these three extracts, only the nonpolar (pentane) one stimulated egg laying by females. Although we did not find a role for volatile plant chemicals in host finding, they appeared to stimulate increased egg laying when the female was on the plant. It appears likely that these chemical and tactile stimuli in C. japonica are general stimuli, which may be found in a large number of plants and, in combination with the feeding preferences of the larva, may explain the generalist herbivorous nature of this pest. [ABSTRACT FROM AUTHOR]

The pretreatment symptomatology of 40 inner-city and 49 rural day hospital patients was compared. Except for urban/rural residence, patient groups were similar in demographic and clinical background. Rural patients were judged by clinicians to be more hostile and more grandiose than their urban counterparts; the latter were rated more perceptually disturbed, more impaired, and less adaptable than the former. According to relatives' evaluations, urban patients were more helpless and less stable than rural patients. The following interpretive hypothesis was offered: symptomatology of patients treated in an urban community tends to be more passive and hence less visibly deviant than that of their rural counterparts. [ABSTRACT FROM AUTHOR]

Thirty-six urban and 44 rural psychiatric day hospital patients were evaluated at the time of their admission to treatment and just prior to release. Thirty-three of the former and 40 of the latter (91% of the treatment sample) were assessed after two and 12 months of fulltime life in the community. At time of release, symptomatic improvement was greater in urban than in rural patients. This advantage had all but disappeared at the two-month follow-up evaluation and was entirely absent one year after patients' release. At that time, symptomatology in the two groups, as rated by clinicians, was virtually identical; objective criteria placed urban and rural patients at approximately the same level of social performance. Relatives, however, saw urban patients as less socially competent, more negativistic, more helpless, and more withdrawn than rural patients. [ABSTRACT FROM AUTHOR]

Seropositive rheumatoid arthritis (RA) patients were found to have high numbers of spontaneously occurring cells making rheumatoid factor (RF) reactive with human IgG as measured by a RF plaque forming cell (RF-PFC) assay. There was a significant positive correlation between the number of RF-PFC and both disease activity measured by the sedimentation rate and RF titer measured by the RA latex test. Aggregated IgG and pokeweed mitogen were equally effective stimulators of RF-PFC in cultures of RA peripheral blood mononuclear leukocytes. The rheumatoid ratio of helper (T4): suppressor (T8) T lymphocytes was also significantly increased over the ratio of normal controls, but this ratio did not correlate with the number of RF-PFC. Aggregated IgG or immune complexes may be responsible for stimulating RA RF-PFC in vivo. [ABSTRACT FROM AUTHOR]

Diel and lunar reproductive patterns of the Caribbean and Pacific sergeant major damselfishes Abudefduf saxatilis and A. troschelii respectively, were studied i the San Blas and Northern Perls Islands of Panama in 1981 and 1982. These are sister-species that have diverged since the uplift of the isthmus of Panama. Caribbean A. saxatilis females typically complete spawning in the nests of males earlier in the morning than do Pacific A. troschelii females. Spawning is rarely observed during the afternoon. Hatching occurs four or five days after spawning in the Caribbean species, and after four days in the Pacific species. In both, fry hatch during the hour following sunset. There also are differences in lunar patterns of spawning between the two species. The Caribbean A. saxatilis spawns throughout the month, exhibiting no lunar periodicity. In the Pacific A. troschelii spawns within nine days on either side of new moon. During the wet season, reproductive activity at a site spans three or four days, but is extended to eight or more days during dry season upwelling in the Bay of Panama. Thus, reproductive synchrony is much greater within than between colonies of the Pacific sergeant major, particularly in the wet season. Reproductive synchrony in the Pacific sergeant major might be beneficial because fry hatching at dusk encounter favorable tides for transport away from reef-based predators around new moon, or because reproductive synchrony reduces the risk of predation on unhatched embryos in nests guarded by males. Tidal amplitude and the rate of predation on embryos in nests are greater in the Pacific. [ABSTRACT FROM AUTHOR]

In Crystal Lake, British Columbia, small fry (≤15 mm SL) of the threespine stickleback ( Gasterosteus aculeatus) are concentrated in vegetation while larger fry are not. Because fry in all size classes feed primarily on zooplankton, even when in vegetation, we hypothesized that size-limited predation was responsible for the observed shift in habitat use with size. The major predators on fry in Crystal Lake are adult threespine stickleback, the water scorpion, Ranatra sp. (Hemiptera: Nepidae), backswimmers, Notonecta spp. (Hemiptera: Notonectidae), and dragonfly naiads of the genus Aeshna (Odonata: Aeschnidae). On the basis of distribution and hunting behavior we excluded the insects Ranatra sp., and Notonecta sp. as causal agents for this shift in resource by fry in water >0.25 m deep. Ranatra was found almost exclusively near the shoreline in water <0.25 m deep, and both insects hunted primarily as ambush predators within vegetation. Such predators seemed more likely to drive vulnerable fry from vegetation than to restrict them to it. In contrast, Aeshna naiads and adult stickleback frequently hunted outside of vegetation. In prey preference experiments the naiads did not show the decline in predation efficiency on fry >15 mm SL that would be expected if size-limited predation by this insect was responsible for the observed shift in resource use by fry. Adult stickleback only fed on fry <15 mm SL, and in an experimental situation, consumed fry at a rate 10 times greater than that exhibited by any of the insects. Predation experiments demonstrated that small fry (11-15 mm) spent more time in vegetation in the presence of adult conspecifics than they did in control pools, as would be expected if size-limited cannibalism caused small, vulnerable fry to be restricted to vegetation. Fry >15 mm SL were found outside of vegetation more often than in control treatments. The probable cause of this result is that adults become aggressive toward fry at this size, and often could be seen chasing large fry from vegetation during the experiments. Dragonfly naiads ( Aeshna spp.) spent most of their time in vegetation in the experimental pools. Both size classes of fry spent less time in vegetation in the presence of dragonfly naiads than they did in control treatments, an apparent reflection of their similar vulnerabilities to these naiads. The presence of vegetation in pools reduced predation rates by adult stickleback on small fry. Because the experiments presented here indicate that fry are capable of rapidly assessing predation risk and of altering their behavior adaptively, we conclude that small fry occupy vegetation as a refuge from cannibalism. Once fry have reached the size-threshold at which they are no longer vulnerable to adult conspecifics they are able to forage farther from vegetation thereby reducing risk of predation by insects in vegetation and possibly acquiring more abundant food resources. [ABSTRACT FROM AUTHOR]

The article presents a study on the development and preliminary validation of a nondestructive method in measuring the growth of Fathead minnow (Pimeohales Dromelas) during subchronic toxicity assessment. The study used linear regression analyses, photographic methods and image analysis techniques, and image processing software. Results show that the growth of the Fathead minnow was determined during day six for the fifth municipal effluent (M5) and day for of six M6.

TNF is a potent cytokine which can induce many of the pathological changes associated with inflammatory disease. In vitro studies have demonstrated that 5-lipoxygenase products promote the production of TNF by activated macrophages, suggesting that 5-lipoxygenase inhibitors may have therapeutic utility for the treatment of inflammatory conditions. A rat airpouch model of inflammation has been used to investigate the relationship between eicosanoid generation and TNF production in vivo. Injection of zymosan into the airpouch caused a time-dependent stimulation of TNF production which preceded leukotriene generation by at least 30 minutes. Injection of LPS into the airpouch also stimulated TNF production but not leukotriene generation. The selective 5-lipoxygenase inhibitors, ICI207968, A64077 and BWA4C, and the 5-lipoxygenase translocation inhibitor MK886, decreased leukotriene generation but enhanced TNF production. Taken together, these results do not support a role for 5-lipoxygenase products in the regulation of TNF production in vivo. [ABSTRACT FROM AUTHOR]

Polymorphonuclear leukocytes (PMNL) are prominent at sites of acute inflammation. Their infiltration is stimulated under pathological conditions by a variety of agents which include bacteria, immune complexes and complement derived chemotactic peptides. Recently attention was focussed on the 5-lipoxygenase product leukotriene B (LTB) which has been demonstrated to induce the key features associated with an acute inflammatory reaction. However, evidence supporting a pro-inflammatory role for LTB, and therefore the anti-inflammatory efficacy of 5-lipoxygenase inhibitors, is largely circumstantial. Moreover, there are concerns that other chemotactic factors, notably Ca, may compensate for the absence of LTB. Here we challenge this view and, on the basis of recent experimental and clinical data suggest that LTB does not simply duplicate the activity of Ca. Instead we propose that their predominant site(s) of action differ in such a way that they may synergise in mediating PMNL recruitment. [ABSTRACT FROM AUTHOR]

Cultures of rabbit retinal pigment epithelium (RPE) were exposed to normal vitreous and to vitreous injured by intravitreal injection of foreign particles. Counts of labeled RPE nuclei after incubation withH-thymidine in vitro indicated an increase in DNA synthesis with exposure to normal vitreous and an even greater increase with exposure to injured vitreous. Fractionation of injured vitreous demonstrated that the apparent proliferation stimulus resided in the cell-free supernate. The data suggest that normal vitreous contains a humoral factor that stimulates RPE proliferation and that levels of an active agent increase after vitreal injury. RPE injected into the vitreous also responds by increased DNA synthesis to subsequent vitreal injury. This observation implies that foreign substances in the vitreous, as after vitreal hemorrhage, promote development of extraretinopathies involving RPE by stimulating intravitreal proliferation of invasive RPE cells. [ABSTRACT FROM AUTHOR]

Methoxyalkyl thiazoles are novel 5-lipoxygenase inhibitors which are neither redox agents nor iron chelators and are exemplified by ICI211965 [1-(3-naphth-2-ylmethoxy)phenyl)-1-(thiazol-2-yl)propyl methyl ether]. ICI211965 potently inhibits LTC synthesis in murine macrophages (IC=0.0085 μ M) and its selectivity with respect to cyclo-oxygenase (>5800) is greater than any previously reported lipoxygenase inhibitor. ICI211965 also selectively inhibits LTB synthesis by human blood in vitro (IC=0.45 μ M) and rat blood ex vivo (ED=10 mg/Kg, p.o.). Methoxyalkyl thiazoles exhibit a tight structure activity relationship and resolution of a chiral member of the series demonstrates that 5-lipoxygenase inhibition resides largely in one enantiomer. Methoxyalkyl thiazoles represent the first class of agents for which 5-lipoxygenase inhibition is mediated by specific, enantioselective interaction with the enzyme. [ABSTRACT FROM AUTHOR]

The object of this study was to investigate the importance of omega oxidation in regulating leukotriene B (LTB) levels in man. In human polymorphonuclear leukocytes metabolism of LTB was rapid but was critically dependent on PMN number: greater than 1.5×10 PMN/ml were required. Metabolism of LTB was blocked in the presence of plasma. In whole blood and in PMN-rich rheumatoid synovial fluids no significant metabolism of LTB was detected within 30 min at 37°C. We conclude that LTB metabolism at inflamed sites will be regulated both by cellular content and the degree of plasma exudation. In most pathological conditions rapid exchange with the micro-vasculature will be more important than metabolism in limiting LTB levels. [ABSTRACT FROM AUTHOR]

Tropical tuna fisheries are central to food security and economic development of many regions of the world. Contemporary population assessment and management generally assume these fisheries exploit a single mixed spawning population, within ocean basins. To date population genetics has lacked the required power to conclusively test this assumption. Here we demonstrate heterogeneous population structure among yellowfin tuna sampled at three locations across the Pacific Ocean (western, central, and eastern) via analysis of double digest restriction-site associated DNA using Next Generation Sequencing technology. The differences among locations are such that individuals sampled from one of the three regions examined can be assigned with close to 100% accuracy demonstrating the power of this approach for providing practical markers for fishery independent verification of catch provenance in a way not achieved by previous techniques. Given these results, an extended pan-tropical survey of yellowfin tuna using this approach will not only help combat the largest threat to sustainable fisheries (i.e. illegal, unreported, and unregulated fishing) but will also provide a basis to transform current monitoring, assessment, and management approaches for this globally significant species. [ABSTRACT FROM AUTHOR]