Artificial Cage Research Articles

Detection of Soybean Insect Pest and a Forecasting Platform Using Deep Learning with Unmanned Ground Vehicles

Soybeans (Glycine max (L.) Merr.), a popular food resource worldwide, have various uses throughout the industry, from everyday foods and health functional foods to cosmetics. Soybeans are vulnerable to pests such as stink bugs, beetles, mites, and moths, which reduce yields. Riptortus pedestris (R. pedestris) has been reported to cause damage to pods and leaves throughout the soybean growing season. In this study, an experiment was conducted to detect R. pedestris according to three different environmental conditions (pod filling stage, maturity stage, artificial cage) by developing a surveillance platform based on an unmanned ground vehicle (UGV) GoPro CAM. Deep learning technology (MRCNN, YOLOv3, Detectron2)-based models used in this experiment can be quickly challenged (i.e., built with lightweight parameter) immediately through a web application. The image dataset was distributed by random selection for training, validation, and testing and then preprocessed by labeling the image for annotation. The deep learning model localized and classified the R. pedestris individuals through a bounding box and masking in the image data. The model achieved high performances, at 0.952, 0.716, and 0.873, respectively, represented through the calculated means of average precision (mAP) value. The manufactured model will enable the identification of R. pedestris in the field and can be an effective tool for insect forecasting in the early stage of pest outbreaks in crop production.

Comparative study of stator current-based and vibration-based methods for railway traction motor bearing cage fault diagnosis at high-speed condition

Traction motor’s rolling element bearings are one of the most critical components for the structural health monitoring of high-speed train vehicles. Most structural health monitoring techniques for railway rolling element bearings are using vibration signal. However, the vibration characteristic of cage defect is difficult to be transmitted to external monitoring point owing to the location of cage in bearing. Hence, the cage defect of Railway Traction Motor Bearing (RTMB) is usually difficult to be recognized with motor housing vibration acceleration signal. Considering Induction Motor (IM) itself a sensor, the mechanical imbalance of bearing cage defect can reflect in stator current through the motor gap magnetic field rather than a solid transmission path. A novel strategy with stator current for monitoring the traction motor bearing cage health status in High-Speed Train (HST) is proposed in this paper. This method requires no additional sensor in the practical application. To prove the strategy is feasible and more effective than vibration-based method for the cage fault diagnosis of RTMB, a comprehensive experiment investigation with a real railway traction motor of a HST is completed. Artificial cage defects are processed on bearings at both ends of the induction motor, respectively. Three high-speed (≥250 km/h) conditions are observed. The data analysis results show that vibration-based method is almost invalid at high-speed condition and the proposed current-based method is feasible and effective for the fault diagnosis of high-speed railway traction motor bearing cage.

Artificial Protein Cage Delivers Active Protein Cargos to the Cell Interior.

Artificial protein cages have potential as programmable, protective carriers of fragile macromolecules to cells. While natural cages and VLPs have been extensively exploited, the use of artificial cages to deliver active proteins to cells has not yet been shown. TRAP-cage is an artificial protein cage with an unusual geometry and extremely high stability, which can be triggered to break apart in the presence of cellular reducing agents. Here, we demonstrate that TRAP-cage can be filled with a protein cargo and decorated with a cell-penetrating peptide, allowing it to enter cells. Tracking of both the TRAP-cage and the cargo shows that the protein of interest can be successfully delivered intracellularly in the active form. These results provide a valuable proof of concept for the further development of TRAP-cage as a delivery platform.

Anterior cervical discectomy and fusion with polyetheretherketone cages in the management of single and double level cervical spondylotic myelopathy-our experiences of 80 cases

Background: Anterior cervical discectomy with fusion (ACDF) is challenging with respect to both patient selection and choice of surgical procedure.Objectives: The aim of this study was to evaluate the clinical outcome of anterior cervical discectomy and fusion with an artificial cage made of polyetheretherketoneMaterials & Methods: From January 2012 to January 2017, 80 consecutive patients referred to the Department of spine surgery, Bangabandhu Shekh Mujib Medical University were recruited for the study. Postoperative Clinical outcome assessed with Nurick scale for myelopathy, Odom's criteria for functional outcome and Visual Analogue Scale (VAS) for both neck and arm pain. Radiological fusion was assessed by X-ray. Operative complications were reported.Results: 36 patients were operated for one level discectomy and fusion with PEEK cages and 44 patients for two levels. There were 48 (60%) males and 32 (40%) females. The age of the patients ranged from 30-72 years, a mean ± SD 45 ± 8.34. At the 2 years clinical follow-up, there were significant post operative improvements of Nurick scale, and VAS comparative to preoperative record. According to Odom's criteria, 72/80 patients (90%) were graded excellent-good.Conclusion: Anterior cervical discectomy and fusion with polyetheretherketone (PEEK) cage is an effective treatment of cervical myelopathy having higher fusion rate and lack of donor site morbidity.KYAMC Journal Vol. 9, No.-1, April 2018, Page 32-34

Membrane protein oligomers by design

Protein Design In recent years, soluble protein design has achieved successes such as artificial enzymes and large protein cages. Membrane proteins present a considerable design challenge, but here too there have been advances, including the design of a zinc-transporting tetramer. Lu et al. report

In Spondylotic Cervical Myelopathy Anterior Cervical Discectomy and Fusion by Peek Cage Without Plate Reinforcement is a Standard Method of Treatment

Background: Anterior cervical discectomy with fusion (ACDF) is challenging with respect to both patient selection and choice of surgical procedure.Objective: The aim of this study was to evaluate the clinical outcome of anterior cervical discectomy and fusion with an artificial cage made of polyetheretherketone .Patients and Methods: From January 2012 to January 2016, 40 consecutive patients referred to the Department of spine surgery, Bangabandhu Shekh Mujib Medical University were recruited for the study.Postoperative Clinical outcome assessd with Nurick scale for myelopathy, Odom’s criteria for functional outcome and Visual Analogue Scale (VAS) for both neck and arm pain. Radiological fusion was assessed by X-ray. Operative complications were reported.Results: 18 patients were operated for one level discectomy and fusion with PEEK cages and 22 patients for two levels. There were 24 (60%) males and 16 (40%) females. The age of the patients ranged from 30-72 years, a mean ± SD 45±8.34. At the 2 years clinical follow-up, there were significant post operative improvements of Nurick scale, and VAS comparative to preoperative record. According to Odom’s criteria, 36/40 patients (90%) were graded excellentgood.Conclusion: Anterior cervical discectomy and fusion with polyetheretherketone (PEEK) cage is an effective treatment of cervical myelopathy having higher fusion rate and lack of donor site morbidity.J Dhaka Medical College, Vol. 25, No.2, October, 2016, Page 110-114

Self-Injurious Behavior (SIB) as a Maladaptive Function of Previous Learning Experience in a Female Pig-Tail Macaque Model (A Hypothesis)

Aim. This paper aims to describe how to decrease hair-plucking behavior in a female pig-tail macaque model as one of Self-Injurious Behavior (SIB) representations of human behavior by using a different way called 'pulling back' technique. Method. An action researched by applying an environmental analyses used to examined its effectiveness on the case. The subject inserted from an artificial individual cage without any grass into a semi natural cage with plenty of grass, leaf, and insects. An instantaneous sampling method (per minute in a ten minutes) used to calculated the amount of hair-plucking behavior between two conditions. Result and discussion. The level of hair-plucking behavior was lower at the semi natural cage with plenty of grass, leaf, and insects. It shown us that hair-plucking behavior had been replaced by plucking grass, leaf, and insects. It seems that plucking grass, leaf, and insects as a previous learning experience had evolved into a different form of maladaptive function as hair-plucking behavior. Although plucking behavior has a central function of feeding behavior since we knew that non-human primates used their hands to hold the food rather than other lower species, but here this behavior faced to malfunction since the behavior couldn't keep its normal function to support survival effort rather than produced serious injuried-body. Here, hair-plucking behavior seems like to be a consequence or side-effect of tick-seeking behavior. Conclusion. These results may have a natural implication to Self-Injurious Behavior (SIB) in human. In human, a self could be a substitute-target for injurious behavior when the other one than self was unreachable. Self-Injurious Behavior (SIB) may as replacement of environmental-injurious, partner-injurious, or other-injurious. Based on these results we propose that a 'pulling back' technique may use to reduce Self-Injurious Behavior (SIB) by seeking and kept the original function of the certain behavior when it failed in a certain adaptation levels in a changing world.

Smells familiar: group-joining decisions of predatory mites are mediated by olfactory cues of social familiarity

Group-living animals frequently have to trade off the costs and benefits of leaving an established group and joining another group. Owing to their high fitness relevance, group-joining decisions are commonly nonrandom and may be based on traits of both individual members and the group such as life stage, body size, social status and group density or size, respectively. Many group-living animals are able to recognize and to associate preferentially with familiar individuals, i.e. those encountered before. Hence, after dispersing from established groups, animals commonly have to decide whether to join a new familiar or unfamiliar group. Using binary choice situations we assessed the effects of social familiarity on group-joining behaviour of the plant-inhabiting predatory mite Phytoseiulus persimilis. Group living in P. persimilis is brought about by the patchy distribution of its spider mite prey and mutual conspecific attraction. In the first experiment, gravid predator females given a choice between spider mite patches occupied by unfamiliar and familiar groups of females strongly preferred to join familiar groups and to deposit their eggs in these patches. Preference for socially familiar groups was robust across biases of spider mite prey densities between choice options. The second experiment revealed that the predatory mite females can smell social familiarity from a distance. Females subjected to odour choice situations in artificial cages were more strongly attracted to the odour of familiar than unfamiliar groups. We argue that P. persimilis females preferentially join socially familiar groups because a familiar social environment relaxes competition and optimizes foraging and reproduction.

From repulsion to attraction: species- and spatial context-dependent threat sensitive response of the spider mite Tetranychus urticae to predatory mite cues

Prey perceiving predation risk commonly change their behavior to avoid predation. However, antipredator strategies are costly. Therefore, according to the threat-sensitive predator avoidance hypothesis, prey should match the intensity of their antipredator behaviors to the degree of threat, which may depend on the predator species and the spatial context. We assessed threat sensitivity of the two-spotted spider mite, Tetranychus urticae, to the cues of three predatory mites, Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius andersoni, posing different degrees of risk in two spatial contexts. We first conducted a no-choice test measuring oviposition and activity of T. urticae exposed to chemical traces of predators or traces plus predator eggs. Then, we tested the site preference of T. urticae in choice tests, using artificial cages and leaves. In the no-choice test, T. urticae deposited their first egg later in the presence of cues of P. persimilis than of the other two predators and cue absence, indicating interspecific threat-sensitivity. T. urticae laid also fewer eggs in the presence of cues of P. persimilis and A. andersoni than of N. californicus and cue absence. In the artificial cage test, the spider mites preferred the site with predator traces, whereas in the leaf test, they preferentially resided on leaves without traces. We argue that in a nonplant environment, chemical predator traces do not indicate a risk for T. urticae, and instead, these traces function as indirect habitat cues. The spider mites were attracted to these cues because they associated them with the existence of a nearby host plant.

Analytical solution for the depolarization of hyperpolarized nuclei by chemical exchange saturation transfer between free and encapsulated xenon (HyperCEST)

We present an analytical solution of the Bloch-McConnell equations for the case of chemical exchange saturation transfer between hyperpolarized nuclei in cavities and in solvent (HyperCEST experiment). This allows quantitative investigation of host-guest interactions by means of nuclear magnetic resonance spectroscopy and, due to the strong HyperCEST signal enhancement, even NMR imaging. Hosts of interest can be hydrophobic cavities in macromolecules or artificial cages like cryptophane-A which was proposed as a targeted biosensor. Relevant system parameters as exchange rate and host concentration can be obtained from the monoexponential depolarization process which is shown to be governed by the smallest eigenvalue in modulus. For this dominant eigenvalue we present a useful approximation leading to the depolarization rate for the case of on- and off-resonant irradiation. It is shown that this rate is a generalization of the longitudinal relaxation rate in the rotating frame. We demonstrate for the free and cryptophane-A-encapsulated xenon system, by comparison with numerical simulations, that HyperCEST experiments are precisely described in the valid range of this widely applicable analytical approximation. Altogether, the proposed analytical solution allows optimization and quantitative analysis of HyperCEST experiments but also characterization and optimal design of possible biosensors.

Conformationally flexible chiral supramolecular catalysts for enantioselective Diels–Alder reactions with anomalous endo/exo selectivities

The potential of supramolecular catalysts to realize anomalous regio- and/or stereoselectivity in organic synthesis is highly attractive. To date, there have been a few examples of non-polymeric and non-covalent chiral supramolecular catalysts that induce practical enantioselectivity. In this regard, a metal-organic framework (MOF) may be one of the most important techniques for constructing conformationally rigid supramolecular catalysts. However, it is not easy to use the MOF technique to fine-tune a much more precise cage in catalysts for anomalous purposes. To establish high catalytic activity with anomalous regio- and/or stereoselectivity, in principle, an artificial cage should be conformationally flexible, like an active pocket in an enzyme with an induced-fit function. In this feature article, we focus on the anomalous endo/exo-selective Diels-Alder reaction, and overview the development of the successive catalysts including our recent highly active, conformationally flexible, and chiral supramolecular catalysts. The evolution from 'ready-made' single-molecule catalysts to 'tailor-made' supramolecular catalysts could offer not only high enantioselectivity but also high anomalous endo/exo-selectivities due to substrate-specific characteristics, as with enzymes.

Clinical outcome of cervical disc replacement and adjacent cage fusion for multi-segmental cervical disc herniation

Objective To evaluate the clinical outcome of artificial cervical disc replacement and cage fusion in the treatment of multi-segmental cervical disc herniation. Methods A total of 39 patients with multi-level cervical disc herniation were treated with disc replacement and adjacent segment cage fusion at one stage. There were 29 patients with two level cervical disc herniation, nine with three level cervical disc herniation and one with four level cervical disc herniation. Of the patients, there were 17 male and 22 female, aged between 35 and 63 years ( mean age 47 years). The herniated disc was located at C3-4 and C4-5 in two patients, C4-5 and C5-6 in 15, C5-6 and C6-7 in nine, C4-5 and C6-7 in three, C3-4,C4-5 and C5-6 in four, C4-5, C5-6 and C6-7 in five and C3-4, C4-8 , C5-6 and C6-7 in one. There were 18 patients with myelopathy and 21 with radieulopathy. The stabilization and the range of motion of implanted disc,the fusion of cage and the displacement of cage were observed on dynamic radiograph postoperatively. The clinical symptom and the neurological function were evaluated according to JOA score and odom' s criteria. Postoperative clinical symptoms and daily function were evaluated by using neck disability index (NDI) scale. Results Twenty-nine patients with bi-level cervical disc herniation underwent single level disc replacement and cage fusion on adjacent segment. Nine patients with three level disc herniation underwent single level disc replacement in seven and level cage fusion on adjacent segment in two. Twopatients underwent two level disc replacement and one level cage fusion. One patient with four level disc herniation was treated with two level disc replacement and two level cage fusion. The patients were followed up for from 6 moths to 3 years, which showed that definite stabilization was achieved for all disc with average range of motion for 9.3 degrees postoperatively. Solid fusion was achieved in all cage, with no subsidence or displacement of cage. The JOA score was increased from 9.1 to 13.2 at final follow up and the NDI (neck disability index) score decreased from 41.8 reduced to 29.5 at final follow up. The clinical success rate (excellent/good/fair) according to Odom' s Criteria was 85%. Conclusion Cervical disc replacement and cage fusion can attain definite stabilization and satisfactory mobility and provide a new effective treatment for cervical disc herniation. The long-term outcome needs further clinical followup. Key words: Intervertebral disk displacemant; Cervical vertebrae; Cervical disc prosthesis

A new passive collector to assess settlement rates, substrate selection and predation pressure in decapod crustacean larvae

Quantitative sampling and experiments evaluating larval settlement of marine invertebrates require an effective, highly replicable sampling unit. Artificial collectors, cages and solid trays have been used to assess spatial and temporal patterns of postlarval settlement of decapod crustaceans. However, because of problems with sample retention upon retrieval, the interpretation of data from artificial collectors can be problematic. Moreover, the costs and time invested in construction can be high, especially in high-energy subtidal environments where there is a considerable risk of damage and loss. In this study, we describe and test a new passive collector for postlarvae of benthic decapod crustaceans. The device is equipped with a mechanism that covers the collector surface during deployment and retrieval, but exposes it while at rest on the sea bed. The collector design also proved effective in determining settlement patterns, substrate preferences and predation effects. In general, passive collectors are effective in monitoring settlement rates for a diversity of species and therefore will be useful in biodiversity studies. Densities of megalopae closely approximated those in comparable natural habitats collected by diver-based suction sampling. Megalopae exhibited a strong preference for structurally heterogeneous substrates. Megalopal settlement to experimental substrates was statistically the same with and without predator exclusion mesh, indicating that the mesh does not produce undue behavioral artifacts, and that predation pressure was negligible at the experimental sites. These collectors represent a versatile alternative to be applied to a wide variety of questions regarding the settlement and early post-settlement processes in brachyuran crabs, as well as other benthic species and lend themselves well to a variety of manipulative experiments in the subtidal environment.

Anterior cervical discectomy with fusion in patients with cervical disc degeneration: a prospective outcome study of 258 patients (181 fused with autologous bone graft and 77 fused with a PEEK cage)

BackgroundAnterior cervical discectomy with fusion (ACDF) is challenging with respect to both patient selection and choice of surgical procedure. The aim of this study was to evaluate the clinical outcome of ACDF, with respect to both patient selection and choice of surgical procedure: fusion with an autologous iliac crest graft (AICG) versus fusion with an artificial cage made of polyetheretherketone (PEEK).MethodsThis was a non-randomized prospective single-center outcome study of 258 patients who underwent ACDF for cervical disc degeneration (CDD). Fusion was attained with either tricortical AICG or PEEK cages without additional anterior plating, with treatment selected at surgeon's discretion. Radicular pain, neck-pain, headache and patient satisfaction with the treatment were scored using the visual analogue scale (VAS).ResultsThe median age was 47.5 (28.3-82.8) years, and 44% of patients were female. 59% had single-level ACDF, 40% had two level ACDF and 1% had three-level ACDF. Of the patients, 181 were fused with AICG and 77 with a PEEK-cage. After surgery, the patients showed a significant reduction in radicular pain (ΔVAS = 3.05), neck pain (ΔVAS = 2.30) and headache (ΔVAS = 0.55). Six months after surgery, 48% of patients had returned to work: however 24% were still receiving workers' compensation.Using univariate and multivariate analyses we found that high preoperative pain intensity was significantly associated with a decrease in pain intensity after surgery, for all three pain categories. There were no significant correlations between pain relief and the following patient characteristics: fusion method (AICG or PEEK-cage), sex, age, number of levels fused, disc level fused, previous neck surgery (except for neck pain), previous neck trauma, or preoperative symptom duration. Two hundred out of the 256 (78%) patients evaluated the surgical result as successful. Only 27/256 (11%) classified the surgical result as a failure. Patient satisfaction was significantly associated with pain relief after surgery.ConclusionsACDF is an effective treatment for radicular pain in selected patients with CDD after six months follow up.Because of similar clinical outcomes and lack of donor site morbidity when using PEEK, we now prefer fusion with PEEK cage to AICG.Lengthy symptom duration was not a negative prognostic marker in our patient population.The number of patients who returned to work 6 months after surgery was lower than expected.

Do mangrove root structures function to shelter benthic macrofauna from predators?

Clarification of the role of mangrove root structures as shelter from predators for benthic animals was investigated by considering (1) the impact of predation on benthic faunal communities in a mangrove forest as indicated by a predator exclusion experiment, and (2) the uses and effects of mangrove root structures by benthic animals under laboratory conditions. In the exclusion experiment, three treatments (predator exclusion cages, partial cages and un-caged controls) were established on surface substrates in each of 3 microhabitats (tidal creek, mangrove cover present and mangrove cover absent) in a Rhizophora mangrove forest in Southern Thailand. After 1 month, benthic invertebrates were sampled and comparisons made of their species' richness, abundance and biomass among the treatments. Laboratory experiments were undertaken in tanks containing artificial mangrove roots, using 2 dominant crab species ( Perisesarma indiarum and Uca bengali) as prey and the barred mudskipper Periophthalmus argentilineatus as predator. Crab preference for root structure and predation rates were recorded. Predator exclusion from the mangrove area resulted in enhanced species' richness, abundance and biomass of benthic invertebrates in all microhabitats, including those with mangrove roots. However, the partial cage treatment did not change such characteristics, indicating that the artificial cage itself did not affect the animals. The laboratory experiments demonstrated that crab preferences for root structures were not influenced by predator presence, and that root structures did not reduce crab predation rates. Such process of dominant species might be cause for significant predation in field benthic community. The overall results indicated that predation was significant for species' richness, abundance and biomass of benthic mangrove forest communities, and vertical root structures did not necessarily provide effective shelter for benthic animals.

Instrumented Posterior Lumbar Interbody Fusion in Adult Spondylolisthesis

It is unclear whether using artificial cages increases fusion rates compared with use of bone chips alone in posterior lumbar interbody fusion for patients with lumbar spondylolisthesis. We hypothesized artificial cages for posterior lumbar interbody fusion would provide better clinical and radiographic outcomes than bone chips alone. We assumed solid fusion would provide good clinical outcomes. We clinically and radiographically followed 34 patients with spondylolisthesis having posterior lumbar interbody fusion with mixed autogenous and allogeneic bone chips alone and 42 patients having posterior lumbar interbody fusion with implantation of artificial cages packed with morselized bone graft. Patients with the artificial cage had better functional improvement in the Oswestry disability index than those with bone chips alone, whereas pain score, patient satisfaction, and fusion rate were similar in the two groups. Postoperative disc height ratio, slip ratio, and segmental lordosis all decreased at final followup in the patients with bone chips alone but remained unchanged in the artificial cage group. The functional outcome correlated with radiographic fusion status. We conclude artificial cages provide better functional outcomes and radiographic improvement than bone chips alone in posterior lumbar interbody fusion for lumbar spondylolisthesis, although both techniques achieved comparable fusion rates. Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Prey suitability of western flower thrips, Frankliniella occidentalis, and onion thrips, Thrips tabaci, for the predatory mite Amblyseius swirskii

Western flower thrips, Frankliniella occidentalis, and onion thrips, Thrips tabaci, are both important polyphagous pests of vegetables and ornamentals in greenhouses. Difficulties in biological control of these pests have prompted a search for new natural enemies. Most recently, the predatory mite Amblyseius swirskii has been commercialised as biological control agent of whiteflies and thrips. However, little is known about the suitability of thrips as prey for A. swirskii. We therefore assessed prey acceptance and life history of A. swirskii when feeding on F. occidentalis and T. tabaci at 25±1°C. Amblyseius swirskii juveniles preyed upon first larval instars of both F. occidentalis and T. tabaci but suffered from high mortality (67 and 78%). Developmental time (egg to adult) of A. swirskii was 7.8 days with either prey species. Adult A. swirskii females readily accepted first larval instars of both thrips species, which were attacked in <20 min on a leaf and <10 min in an artificial cage. Oviposition rates (0.92 and 0.99 eggs/female/day) and offspring sex ratios (63 and 70% females) were similar with F. occidentalis and T. tabaci as prey. Less than one-third of juveniles reaching adulthood and oviposition rates below one egg/female per day resulted in relatively low intrinsic rates of increase (r m) (0.056 and 0.024 per day with F. occidentalis and T. tabaci, respectively). Altogether, our study suggests that the recently reported superiority of A. swirskii to the widely used Neoseiulus cucumeris in suppression of thrips is due to other traits than its population growth capacity with thrips as prey.

Direct and indirect adverse effects of tomato on the predatory mite Neoseiulus californicus feeding on the spider mite Tetranychus evansi

AbstractPlants may defend themselves against herbivores via morphological traits, chemical traits, or a combination of both. Herbivores that overcome the defensive mechanisms of a plant tend to specialize on this plant due to enhanced protection from natural enemies. Well‐known examples of plants possessing a suite of defensive mechanisms are found in nightshades (Solanaceae), especially in the tomato genus Lycopersicon. The spider mite Tetranychus evansi Baker and Pritchard (Acari: Tetranychidae) is specialized on solanaceous plants and is an invasive pest of tomato in Europe and Africa. Biological control of T. evansi with currently available natural enemies, such as the predatory mites Phytoseiulus persimilis Athias‐Henriot and Neoseiulus californicus McGregor (both Acari: Phytoseiidae), is unsuccessful, with the underlying mechanisms only vaguely known. We hypothesized that T. evansi is a key pest of tomato because this host plant provides a two‐pronged protection from natural enemies. Direct adverse effects of tomato on predators may arise from morphological traits and/or trichome exudates, whereas indirect effects are prey‐mediated through the accumulation of toxic plant compounds. Using a 2 × 3 factorial design, we assessed and separated direct and indirect effects of tomato on the life history of N. californicus feeding on two strains of T. evansi (reared on bean or tomato) on three substrates (tomato leaf, bean leaf, and an artificial cage). Developmental time and oviposition rate of N. californicus were both directly and indirectly negatively affected by tomato whereas offspring sex ratio and survival of juveniles and adult females were unaffected. The direct and indirect, prey‐mediated adverse effects of tomato on N. californicus with T. evansi prey had similar magnitudes and were additive. We conclude that T. evansi per se is a suitable prey species for N. californicus and discuss the results with respect to the potential use of N. californicus as biological control agent of T. evansi on tomato and other host plants.

The invasive bivalve Limnoperna fortunei enhances benthic invertebrate densities in South American floodplain rivers

We assessed the effects of the introduced bivalve L. fortunei on the abundance and biomass of associated benthic invertebrates in South American large floodplain rivers. The survey was based on comparisons of L. fortunei-covered and L. fortunei-barren areas in five artificial cages from where large predators were excluded, exposed to colonization by the mussel for a total of 17 months in the lower Parana river delta. Accompanying invertebrates were dominated by Oligochaeta, Nematoda, Rotifera, Copepoda, Gastropoda, Hirudinea, Chironomidae and nauplii. Also present in minor numbers were Tardigrada, Turbellaria, Cladocera, Ostracoda, Insecta, Hydracarina and Decapoda. Dominant invertebrates were 27–100% more numerous (and hosted 43–100% more biomass) in areas with L. fortunei than in areas barren of the mussel. In areas with L. fortunei, total invertebrate biomass (excluding the bivalve) was positively correlated with mussel biomass, and increased with time of exposure under water. No such trend was observed in areas barren of L. fortunei. It is suggested that higher invertebrate growth is associated with enhanced substrate complexity and, probably, the transfer of organic matter from the plankton to the sediments due to the mussels’ feces and pseudofeces. Some of the adverse ecosystem-wide effects of filter-feeding invasive mussels observed in European and North American water bodies may be offset in the Parana by the extremely high loads of organic matter in these turbid waters.

Variability in the numbers of post-settlement King George whiting (Sillaginidae: Sillaginodes punctata, Cuvier) in relation to predation, habitat complexity and artificial cage structure

The importance of predation by fish in altering abundances of juvenile King George whiting ( Sillaginodes punctata) was examined at multiple locations in Port Phillip Bay, Australia, by manipulating the numbers of piscivorous fish in unvegetated sand and seagrass habitats using cages. Additional information regarding the local abundances of, and habitat use by, the most common piscivorous fish, Western Australian salmon (Arripidae: Arripis truttacea, Cuvier), was gathered using netting surveys and underwater video. Regardless of habitat, abundances of S. punctata were similar in partial cages and uncaged areas. In unvegetated sand, S. punctata were more abundant inside cages than partial cages or uncaged areas. In seagrass, there was no difference in the numbers of S. punctata between caging treatments. Patterns in abundances of S. punctata between cage treatments in each habitat were consistent between sites, but the relative difference in the abundances of S. punctata between habitats was site specific. Abundances of A. truttacea varied significantly between sites, and they consumed a variety of epibenthic fishes including atherinids, clupeids, gobiids, syngnathids and pleuronectids. At one site in Port Phillip Bay (Blairgowrie), A. truttacea occurred more commonly in patches of unvegetated sand than seagrass. Over unvegetated sand, abundances of A. truttacea varied little between partial cages and uncaged areas. The numbers of S. punctata varied between caging treatments and habitats in a manner that was consistent with a model whereby seagrass interferes with foraging by predatory fish and provides juvenile fish with a refuge from predation. The almost total absence of A. truttacea in seagrass habitats and the lack of S. punctata in their diets implies, however, that patterns in S. punctata in seagrass/unvegetated sand mosaics are driven by processes other than direct predation.