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Smallholder farmers in the Asia-Pacific region grow diverse vegetables, often in complex, mixed-cropping systems, offering various opportunities for improved livelihoods. However, farmers often respond to pest-anddisease threats with ill-founded use of agrochemicals which may exacerbate such problems. ACIAR-funded projects in the Asia-Pacific region have helped farmers to develop and adopt integrated pest and crop management approaches, drawing on elements of earlier initiatives, including farmer field schools, but emphasizing a flexible approach that takes into account the local social, cultural and economic context of vegetable farming, and the national regulatory and policy environment. Projects have invested in developing relevant problem-solving research capacity and attitudes among public-sector research partners, as well as information resources appropriate for smallholders. Private sector partners have been engaged in technology development and farmer training, becoming key agents of change. Common and contrasting experiences from projects in the Philippines and Fiji are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The diamondback moth, Plutella xylostella, has developed extremely high levels of resistance to chlorantraniliprole and other classes of insecticides in the field. As microRNAs (miRNAs) play important roles in various biological processes through gene regulation, we examined the miRNA profile of P. xylostella in response to chlorantraniliprole exposure. RNA sequencing analysis showed that insecticide treatment caused significant changes in the abundance of some miRNAs. Increasing exposure time and insecticide concentration induced more dysregulated miRNAs in P. xylostella larvae. We also screened potential target genes for some of the differentially expressed miRNAs (such as miR‐2b‐3p, miR‐14b‐5p and let‐7‐5p), which may play important roles in insecticide resistance development. Exposure of P. xylostella larvae to chlorantraniliprole caused considerable overexpression in the transcript levels of potential target genes cytochrome P450 9f2 (CYP9F2) and 307a1 (CYP307a1). Application of miR‐2b‐3p and miR‐14b‐5p mimics significantly suppressed the relative transcript levels of CYP9F2 and CYP307a1, respectively, in a P. xylostella cell line. Furthermore, enrichment of P. xylostella diet with miR‐2b‐3p mimics significantly increased mortality in deltamethrin‐resistant larvae when exposed to deltamethrin. The results suggest that miR‐2b‐3p may suppress CYP9F2 transcript levels in P. xylostella and consequently inhibit larval detoxification pathways. The findings provide an insight into possible role of miRNAs in regulation of metabolic resistance of insects to insecticides. [ABSTRACT FROM AUTHOR]

Experimental data for an InP-based 40-stage quantum cascade laser structure grown on a 6-in. GaAs substrate with a metamorphic buffer are reported. The laser structure had an Al0.78In0.22As/ In0.73Ga0.27As strain-balanced active region composition and an 8 lm-thick, all-InP waveguide. High reflection coated 3 mm x 30 µm devices processed from the wafer into a ridge-waveguide configuration with a lateral current injection scheme delivered over 200 mW of total peak power at 78 K with lasing observed up to 170 K. No signs of performance degradation were observed during a preliminary 200-min reliability testing. Temperature dependence for threshold current and slope efficiency in the range from 78 K to 230 K can be described with characteristic temperatures of T0 ≈ 460 K and T1 ≈ 210 K, respectively. Lasing was extended to 303 K by applying a partial high reflection coating to the front facet of the laser. [ABSTRACT FROM AUTHOR]

We present a MUSE (Multi-Unit Spectroscopic Explorer) and KMOS (K-band Multi-Object Spectrograph) dynamical study 405 star-forming galaxies at redshift z = 0.28-1.65 (median redshift ... = 0.84). Our sample is representative of the star-forming 'main sequence', with star formation rates of SFR = 0.1-30 M⊙ yr-1 and stellar masses M* = 108-1011 M⊙. For 49 ± 4 per cent of our sample, the dynamics suggest rotational support, 24 ± 3 per cent are unresolved systems and 5 ± 2 per cent appear to be early-stage major mergers with components on 8-30 kpc scales. The remaining 22 ± 5 per cent appear to be dynamically complex, irregular (or face-on systems). For galaxies whose dynamics suggest rotational support, we derive inclination-corrected rotational velocities and show that these systems lie on a similar scaling between stellar mass and specific angular momentum as local spirals with j* = J/M* ∝ M*2/3 but with a redshift evolution that scales as j* ∝ M*2/3 (1 + z)-1. We also identify a correlation between specific angular momentum and disc stability such that galaxies with the highest specific angular momentum (log(j*/M*2/3) > 2.5) are the most stable, with Toomre Q = 1.10 ± 0.18, compared to Q = 0.53 ± 0.22 for galaxies with log(j*/M*2/3) < 2.5. At a fixed mass, the Hubble Space Telescope morphologies of galaxies with the highest specific angular momentum resemble spiral galaxies, whilst those with low specific angular momentum are morphologically complex and dominated by several bright star-forming regions. This suggests that angular momentum plays a major role in defining the stability of gas discs: at z ~ 1, massive galaxies that have discs with low specific angular momentum are globally unstable, clumpy and turbulent systems. In contrast, galaxies with high specific angular momentum have evolved into stable discs with spiral structure where star formation is a local (rather than global) process. [ABSTRACT FROM AUTHOR]

We present the evolution of galaxy sizes, from redshift 2 to 0, for actively star forming and passive galaxies in the cosmological hydrodynamical 100³ cMpc³ simulation of the EAGLE project. We find that the sizes increase with stellar mass, but that the relation weakens with increasing redshift. Separating galaxies by their star formation activity, we find that passive galaxies are typically smaller than active galaxies at a fixed stellar mass. These trends are consistent with those found in observations and the level of agreement between the predicted and observed size-mass relations is of the order of 0.1 dex for z < 1 and 0.2-0.3 dex from redshift 1 to 2. We use the simulation to compare the evolution of individual galaxies with that of the population as a whole. While the evolution of the size-stellar mass relation for active galaxies provides a good proxy for the evolution of individual galaxies, the evolution of individual passive galaxies is not well represented by the observed size-mass relation due to the evolving number density of passive galaxies. Observations of z ~ 2 galaxies have revealed an abundance of massive red compact galaxies, which depletes below z ~ 1. We find that a similar population forms naturally in the simulation. Comparing these galaxies with their z = 0 descendants, we find that all compact galaxies grow in size due to the high-redshift stars migrating outwards. Approximately 60 per cent of the compact galaxies increase in size further due to renewed star formation and/or mergers. [ABSTRACT FROM AUTHOR]

The banana-spotting bug, Amblypelta lutescens lutescens Distant (Hemiptera: Coreidae), is native to Australia and a major polyphagous pest of many tropical and subtropical horticultural crops in the east and north of the country. Different plant structures (flowers, vegetative flush, and different sized fruit) of avocado, lime, and papaya crops and green bean pods (a known suitable host) were evaluated for their suitability as hosts for A. l. lutescens. Neonate to imago survivorship, the time taken to complete neonate to imago development, preovipositional period, and fecundity were assessed for each crop. Of all the different phenological stages of the plants investigated, A. l. lutescens could complete development to imago on vegetative flush of papaya and lime, papaya flowers, and green bean pods but on no other structures tested. There was higher survivorship to the second instar when neonates fed on green bean pods or flowers or vegetative flush of avocado, lime, or papaya crops than when neonates fed on small, medium, or large fruit of these crops. Insects that developed to the imago on green bean pods were significantly heavier than insects that developed on papaya flowers or papaya vegetative flush. The mean preoviposition period was shorter, and adult females more fecund, if they completed immature development and then fed as adults on papaya vegetative flush or green beans rather than papaya flowers. The data indicate that avocado is not a suitable host for A. l. lutescens, suggesting that adult populations that cause significant pest damage to the fruit of this crop originate elsewhere. [ABSTRACT FROM AUTHOR]

Feedback from energy liberated by gas accretion on to black holes (BHs) is an attractive mechanism to explain the exponential cut-off at the massive end of the galaxy stellar mass function. Most previous implementations of BH accretion in hydrodynamical simulations of galaxy formation have assumed that BHs grow at an accretion rate that is proportion to the Bondi rate. A major concern is that the Bondi accretion rate is inappropriate when the accreting material has significant angular momentum. We present an improved accretion model that takes into account the circularization and subsequent viscous transport of infalling material, and implemented as a 'subgrid' model in hydrodynamic simulations. The resulting accretion rates are generally low in low mass (≲ 1011.5 M⊙) haloes, but show outbursts of Eddington-limited accretion during galaxy mergers. During outbursts these objects strongly resemble quasars. In higher mass haloes, gas accretion peaks at ~10 per cent of the Eddington rate, which is thought to be conducive to the formation of radio jets. The resulting accretion rate depends strongly on the effective pressure of the gas surrounding the BH, which in turn depends strongly on halo mass. This induces a sharp transition in the importance of BH feedback. In small haloes, the growth of galaxies is regulated by star formation and supernova feedback, but above a halo mass of 1011.5 M⊙, rapid BH growth leads to the suppression of star formation and reduced growth of stellar mass with increasing halo mass. [ABSTRACT FROM AUTHOR]

Background Child conduct problems are a major public health priority. Group-based parenting programmes are popular in addressing such problems, but evidence for their longer-term effectiveness is limited. Moreover, process evaluations are rare and little is understood about the key facilitative and inhibitive factors associated with maintaining outcomes in the longer term. Method This study involved the use of qualitative methods as part of a larger process evaluation to explore the longer-term experiences of parents who participated in a randomized controlled trial ( RCT) of the Incredible Years Parenting Programme ( IYPP) in disadvantaged settings in Ireland. A series of one-to-one in-depth interviews was conducted with parents at 12- ( n = 20) and 18-month follow-up ( n = 8) and analysed using constructivist grounded theory. Results Most parents reported positive child behaviour despite several challenges, but a substantial subset reported periods of relapse in positive outcomes. A relapse in child behaviour was linked to relinquishing skills in stressful times, the negative influence of an unsupportive environment, and the perceived ineffectiveness of parenting skills. Resilience in implementing skills despite adversity, and the utilization of available social supports, were associated with the maintenance of positive outcomes. Conclusions Strengthening resilience and social support capacities may be important factors in maintaining positive longer-term outcomes. Those who design, research and deliver parenting programmes might consider the possibility of including a relapse-prevention module and/or the provision of post-intervention supports for more vulnerable families. [ABSTRACT FROM AUTHOR]

The combined action of two lepidoteran pests, Plutella xylostella L. (Plutellidae) and Pieris rapae L. (Pieridae), causes significant yield losses in cabbage (Brassica oleracea variety capitata) crops in the Democratic People's Republic of Korea. Integrated pest management (IPM) strategies for these cropping systems are in their infancy, and sampling plans have not yet been developed. We used statistical resampling to assess the performance of fixed sample size plans (ranging from 10 to 50 plants). First, the precision (D = SE/mean) of the plans in estimating the population mean was assessed. There was substantial variation in achieved D for all sample sizes, and sample sizes of at least 20 and 45 plants were required to achieve the acceptable precision level of D ⩽ 0.3 at least 50 and 75% of the time, respectively. Second, the performance of the plans in classifying the population density relative to an economic threshold (ET) was assessed. To account for the different damage potentials of the two species the ETs were defined in terms of standard insects (SIs), where 1 SI = 1 P. rapae = 5 P. xylostella larvae. The plans were implemented using different economic thresholds (ETs) for the three growth stages of the crop: precupping (I SI/plant), cupping (0.5 SI/plant), and heading (4 SI/plant). Improvement in the classification certainty with increasing sample sizes could be seen through the increasing steepness of operating characteristic curves. Rather thin prescribe a particular plan, we suggest that the results of these analyses be used to inform practitioners of the relative merits of the different sample sizes. [ABSTRACT FROM AUTHOR]

The lepidopteran pests Plutella xylostella L. (Plutellidae) and Pieris rapae L. (Pieridae: Pierini) are responsible for major yield losses of cabbage, Brassica oleracea L. (Brassicaceae), in North Korea. Preliminary integrated pest management (IPM) programmes using economic thresholds (ETs) to schedule insecticide applications have proved promising and have demonstrated marked increases in yield compared to standard farming practice, which relies heavily on synthetic insecticides. To use ETs effectively on a routine basis, farmers need efficient yet sufficiently precise methods of surveying crops for pests. Here we construct and validate binomial sequential sampling plans for the two-species pest complex and for P. rapae alone. The recommended plans would be practical to implement, demanding maximum sample sizes below 50 plants, and proved very slightly conservative with respect to classifying the population relative to the ET (i.e., they were slightly more likely to suggest control at the ET than not). [ABSTRACT FROM AUTHOR]

The Safe Schools/Healthy Students (SS/HS) Initiative is an ambitious and comprehensive prevention initiative to promote evidence-based practice to address school safety and the reduction of substance abuse. This article describes the history of the SS/HS initiative and the national evaluation efforts to monitor the success of the initiative. To gather an overview of program evaluation and dissemination strategies across sites, we conducted a survey of SS/HS sites. Results revealed that most sites used an external evaluator, usually from a private firm, and quasi-experimental designs, although there was variation. We also summarize the strategies, some key findings, and common themes across the evaluation articles in this special issue. Implications for future comprehensive evaluations are discussed. [ABSTRACT FROM AUTHOR]

Adult diamondback moths (DBM), Plutella xylostella L. (Lepidoptera: Plutellidae), inoculated with the fungus Zoophthora radicans, were released within a large field cage containing DBM-infested potted broccoli plants. Larvae and pupae on exposed and caged control plants were examined on five occasions over the next 48 days for evidence of Z. radicans infection. Infected larvae were first detected on exposed plants 4 days after the initial release of adults, and after 48 days the infection level reached 79%. Aerially borne conidia were a factor in transmission of the fungus. Infection had no effect on possible losses of larval and adult cadavers due to scavengers in field crops. In a trial to measure the influence of infection on dispersal, twice as many non-infected as infected males were recaptured in pheromone traps, although the difference in cumulative catch only became significant 3 days after release of the males. In a separate experiment, when adult moths were inoculated with Beauveria bassiana conidia and released into the field cage, DBM larvae collected from 37 of 96 plants sampled 4 days later subsequently died from B. bassiana infection. The distribution of plants from which the infected larvae were collected was random, but the distribution of infected larvae was clustered within the cage. These findings suggest that the auto-dissemination of fungal pathogens may be a feasible strategy for DBM control, provided that epizootics can be established and maintained when DBM population densities are low. [ABSTRACT FROM AUTHOR]

Abstract Aims: Molecular procedures were used to identify Thiothrix spp. in biofilms from sulphide-rich waters in two distinct ecosystems. Methods and Results: Biofilm samples were obtained from two groundwater-fed systems in central and northern Florida, including an artesian spring and municipal water tank. The 16S rDNA in each sample was directly amplified by polymerase chain reaction. Conclusions: Clonal libraries of biofilm 16S rDNA from each site contained rDNA sequences that were 99–99·5% similar to Thiothrix unzii . Significance and Impact of the Study: This is the first report of T. unzii in a natural system. Biofilm formation by Thiothrix spp. can cause fouling in groundwater processing equipment, including municipal water-processing facilities, agricultural irrigation systems and spring water bottling plant filters. Biofouling can have severe economic and human health impacts as it will influence flow rates and related water treatments. Characterization of specific fouling bacteria and their molecular ecology is essential for their regulation. [ABSTRACT FROM AUTHOR]

Laboratory studies investigated the interaction between the fungal entomopathogen Beauveria bassiana (Balsamo) Vuillemin and sublethal doses of the insecticides imidacloprid and cyromazine when applied to larvae of the Colorado potato beetle, Leptinotarsa decemlineata (Say). When second instars were fed potato leaf discs treated with sublethal doses of imidacloprid and a range of doses of B. bassiana, a synergistic action was demonstrated. Similar results were observed when larvae were sprayed directly with B. bassiana conidia and immediately fed leaf discs treated with imidacloprid. No synergistic interaction was detected when larvae were fed leaf discs treated with sublethal doses of imidacloprid 24 h after application of B. bassiana conidia to larvae. However, a synergistic interaction was detected when larvae were fed leaf discs treated with imidacloprid and sprayed with B. bassiana conidia 24 h later. Although sublethal doses of both imidacloprid and the triazine insect growth regulator (IGR) cyromazine prolonged the duration of the second instar, only imidacloprid interacted with B. bassiana to produce a synergistic response in larval mortality. In leaf consumption studies, the highest dose of B. bassiana tested promoted feeding in inoculated second instars. Feeding was inhibited when larvae were fed foliage treated with sublethal doses of imidacloprid and significantly reduced when fed foliage treated with a sublethal dose of cyromazine. Starvation of larvae for 24 h immediately after B. bassiana treatment produced a similar result to the combined treatment of B. bassiana and imidacloprid and increased the level of mycosis when compared with B. bassiana controls. Imidacloprid treatment affected neither the rate of germination of B. bassiana conidia on the insect cuticle nor the rate at which conidia were removed from the integument after application. The statistical analysis used to detect synergism and the possible role of starvation-induced stress factors underlying the observed synergistic interactions are discussed. [ABSTRACT FROM PUBLISHER]

Presents information on a study which examined evidence for the origin of the ovarian cancer cell line SW626. Utilization of immunologic markers for the differentiation of ovarian from colonic primary tumors; Results; Recommendations.