Development of a Two-Finger Haptic Robotic Hand with Novel Stiffness Detection and Impedance Control.

Haptic hands and grippers, designed to enable skillful object manipulation, are pivotal for high-precision interaction with environments. These technologies are particularly vital in fields such as minimally invasive surgery, where they enhance surgical accuracy and tactile feedback: in the development of advanced prosthetic limbs, offering users improved functionality and a more natural sense of touch, and within industrial automation and manufacturing, they contribute to more efficient, safe, and flexible production processes. This paper presents the development of a two-finger robotic hand that employs simple yet precise strategies to manipulate objects without damaging or dropping them. Our innovative approach fused force-sensitive resistor (FSR) sensors with the average current of servomotors to enhance both the speed and accuracy of grasping. Therefore, we aim to create a grasping mechanism that is more dexterous than grippers and less complex than robotic hands. To achieve this goal, we designed a two-finger robotic hand with two degrees of freedom on each finger; an FSR was integrated into each fingertip to enable object categorization and the detection of the initial contact. Subsequently, servomotor currents were monitored continuously to implement impedance control and maintain the grasp of objects in a wide range of stiffness. The proposed hand categorized objects' stiffness upon initial contact and exerted accurate force by fusing FSR and the motor currents. An experimental test was conducted using a Yale-CMU-Berkeley (YCB) object set consisted of a foam ball, an empty soda can, an apple, a glass cup, a plastic cup, and a small milk packet. The robotic hand successfully picked up these objects from a table and sat them down without inflicting any damage or dropping them midway. Our results represent a significant step forward in developing haptic robotic hands with advanced object perception and manipulation capabilities.

Beneficial worm allies warn plants of parasite attack below-ground and reduce above-ground herbivore preference and performance.

Antagonistic interactions among different functional guilds of nematodes have been recognized for quite some time, but the underlying explanatory mechanisms are unclear. We investigated responses of tomato (Solanum lycopersicum) to two functional guilds of nematodes-plant parasite (Meloidogyne javanica) and entomopathogens (Heterorhabditis bacteriophora, Steinernema feltiae below-ground, and S. carpocapsae)-as well as a leaf mining insect (Tuta absoluta) above-ground. Our results indicate that entomopathogenic nematodes (EPNs): (1) reduced root knot nematode (RKN) infestation below-ground, (2) reduced herbivore (T. absoluta) host preference and performance above-ground, and (3) induced overlapping plant defence responses by rapidly activating polyphenol oxidase and guaiacol peroxidase activity in roots, but simultaneously suppressing this activity in above-ground tissues. Concurrently, we investigated potential plant signalling mechanisms underlying these interactions using transcriptome analyses. We found that both entomopathogens and plant parasites triggered immune responses in plant roots with shared gene expression. Secondary metabolite transcripts induced in response to the two nematode functional guilds were generally overlapping and showed an analogous profile of regulation. Likewise, we show that EPNs modulate plant defence against RKN invasion, in part, by suppressing active expression of antioxidant enzymes. Inoculations of roots with EPN triggered an immune response in tomato via upregulated phenylpropanoid metabolism and synthesis of protease inhibitors in plant tissues, which may explain decreased egg laying and developmental performance exhibited by herbivores on EPN-inoculated plants. Furthermore, changes induced in the volatile organic compound-related transcriptome indicated that M. javanica and/or S. carpocapsae inoculation of plants triggered both direct and indirect defences. Our results support the hypothesis that plants "mistake" subterranean EPNs for parasites, and these otherwise beneficial worms activate a battery of plant defences associated with systemic acquired resistance and/or induced systemic resistance with concomitant antagonistic effects on temporally co-occurring subterranean plant pathogenic nematodes and terrestrial herbivores.

Aphid alarm pheromone alters larval behaviour of the predatory gall midge, Aphidoletes aphidimyza and decreases intraguild predation by anthocorid bug, Orius laevigatus.

Intraguild predation is the killing and consuming of a heterospecific competitor that uses similar resources as the prey, and also benefit from preying on each other. We investigated the foraging behaviour of the gallmidge, Aphidoletes aphidimyza, a predator of aphids used for biological control that is also the intraguild prey for most other aphid natural enemies. We focus on how aphid alarm pheromone can alter the behaviour of the gallmidge, and predation by the anthocorid bug Orius laevigatus (O. laevigatus). We hypothesised that gallmidges would respond to the presence of (E)-ß-farnesene (EBF) by leaving the host plant. Since feeding by Aphidoletes gallmidge larvae does not induce EBF emission by aphids, this emission indicates the presence of an intraguild predator. We found that gallmidge larvae reduced their foraging activities and left the plant earlier when exposed to EBF, particularly when aphids were also present. Contrastingly, gallmidge females did not change the time visiting plants when exposed to EBF, but lay more eggs on plants that had a higher aphid density. Lastly, EBF reduced the number of attacks of the intraguild predator, O. laevigatus, on gallmidge larvae, potentially because more gallmidges stopped aphid feeding and moved off the plant at which point O. laevigatus predated on aphids. Our work highlights the importance of understanding how intraguild predation can influence the behaviour of potential biological control agents and the impact on pest control services when other natural enemies are also present.

Plant Growth-Promoting Rhizobacteria Enhance Defense of Strawberry Plants Against Spider Mites.

Plants mediate interactions between below- and above-ground microbial and animal communities. Microbial communities of the rhizosphere commonly include mutualistic symbionts such as mycorrhizal fungi, rhizobia and free-living plant growth-promoting rhizobacteria (PGPR) that may influence plant growth and/or its defense system against aboveground pathogens and herbivores. Here, we scrutinized the effects of three PGPR, Azotobacter chroococcum, Azospirillum brasilense, and Pseudomonas brassicacearum, on life history and population dynamics of two-spotted spider mites, Tetranychus urticae, feeding on aboveground tissue of strawberry plants, and examined associated plant growth and physiology parameters. Our experiments suggest that these three species of free-living rhizobacteria strengthen the constitutive, and/or induce the direct, anti-herbivore defense system of strawberry plants. All three bacterial species exerted adverse effects on life history and population dynamics of T. urticae and positive effects on flowering and physiology of whole strawberry plants. Spider mites, in each life stage and in total, needed longer time to develop on PGPR-treated plants and had lower immature survival rates than those fed on chemically fertilized and untreated plants. Reduced age-specific fecundity, longer developmental time and lower age-specific survival rates of mites feeding on rhizobacteria treated plants reduced their intrinsic rate of increase as compared to mites feeding on chemically fertilized and control plants. The mean abundance was lower in spider mite populations feeding on PGPR-treated strawberries than in those feeding on chemically fertilized and untreated plants. We argue that the three studied PGPR systemically strengthened and/or induced resistance in above-ground plant parts and enhanced the level of biochemical anti-herbivore defense. This was probably achieved by inducing or upregulating the production of secondary plant metabolites, such as phenolics, flavonoids and anthocyanins, which were previously shown to be involved in induced systemic resistance of strawberry plants. Overall, our study emphasizes that PGPR treatment can be a favorable strawberry plant cultivation measure because providing essential nutrients needed for proper plant growth and at the same time decreasing the life history performance and population growth of the notorious herbivorous pest T. urticae.

The Relationship between Household Food Insecurity and Depressive Symptoms among Pregnant Women: A Cross Sectional Study.

Objective: There is growing evidence suggesting that household food insecurity (HFI) is associated with adverse outcomes on mental health; however, limited evidence exists for pregnant women. This study was conducted to determine the relationship between HFI and depressive symptoms among a sample of pregnant women. Method : This cross sectional study was performed on 394 pregnant women referring to the health centers located in Qom, Iran, from October 2017 to March 2019. HFI was evaluated using an 18-item US Household Food Security Survey Module. The Beck Depression Inventory-II questionnaire was applied to determine the severity of depressive symptoms. Logistic regression analysis was used to determine the factors associated with elevated depressive symptoms in the study population. Results: The mean (± standard deviation) age of the study population was 28.59 ± 7.28 years. Almost 48% of participants were food insecure, and 37% experienced elevated levels of depressive symptoms during pregnancy. The prevalence of elevated depressive symptoms was significantly higher in food-insecure (P < 0.001) and unemployed (P = 0.02) women, while it was significantly lower in women with higher education levels (P < 0.001). In the adjusted model, it was revealed that HFI was significantly associated with the higher likelihood of having elevated depressive symptoms (OR = 3.31, 95% CI = 2.07, 5.29), while the higher level of education was negatively associated with the levels of depressive symptoms (OR = 0.40, 95% CI = 0.20, 0.79). Conclusion: HFI was positively associated with the severity of depressive symptoms in a sample of pregnant women. Further studies are needed to confirm this finding. Meanwhile, routine screening of HFI for all pregnant women in the community health centers is recommended.

Effect of Age-Dependent Parasitism in Eggs of Tuta absoluta (Lepidoptera: Gelechiidae) on Intraguild Predation Between Nabis pseudoferus (Hemiptera: Nabidae) and Trichogramma brassicae (Hymenoptera: Trichogrammatidae).

The tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a destructive pest of tomato that can cause up to 100% yield loss. The predatory bug Nabis pseudoferus (Remane) (Hemiptera: Nabidae) and the parasitoid Trichogramma brassicae (Bezdenko) (Hymenoptera: Trichogrammatidae) are natural enemies of this pest. Since the interaction between predators and parasitoids in different trophic levels including intraguild predation (IGP) can decrease or increase the efficiency of natural enemies, the effects of age-dependent parasitism of host eggs on IGP between these two species were investigated under laboratory conditions. In no-choice and choice preference tests, the predatory bug was exposed to 40 parasitized and nonparasitized eggs of different ages (24, 48, and 72 h old). Investigation of switching behavior was conducted using various combinations of tomato leafminer eggs (30:90, 45:75, 60:60, 75:45, and 90:30 nonparasitized:parasitized eggs) using eggs of different ages (24, 48, and 72 h old). In no-choice tests, the highest feeding rate of the predatory bug was 39.21 ± 0.36 eggs on 24-h-old nonparasitized eggs and the lowest feeding rate was 1.4 ± 0.80 eggs on 72-h-old parasitized eggs. In choice tests, comparison of the Manly's ß indices indicated that the predatory bug preferred to feed on nonparasitized eggs with 48- and 72-h-old eggs, but there was no significant preference for the 24-h-old eggs. Results of switching test showed that the linear regression between Manly's ß index and different ratios of nonparasitized eggs to parasitized and nonparasitized eggs was not significant in 72-h-old eggs. However, this regression was significant with 24- and 48-h-old eggs and the predator's preference was dependent upon the ratio of nonparasitized and parasitized tomato leafminer eggs. Results of the current study showed that the increasing age of parasitized egg decreased intensity of IGP between N. pseudoferus and T. brassicae.

Nitrogen Fertilization Increases the Nutritional Quality of Aphis gossypii (Hemiptera: Aphididae) as Prey for Hippodamia variegata (Coleoptera: Coccinellidae) and Alters Predator Foraging Behavior.

Nitrogen (N) fertilization is a common agricultural practice, which, by increasing the quality of plants, also enhances their nutritional suitability for insect herbivores, creating the possibility of a cascade of N across trophic levels, from plant to herbivore to predator. We manipulated the quality of cucumber plants by fertilizing them with three different N rates (110, 160, and 210 ppm), which represented low, medium, and high N levels, respectively. Colonies of Aphis gossypii Glover (Hemiptera: Aphididae) were then reared on these plants and used as prey for adult Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae) in experiments that characterized the predator's foraging behavior and functional response to different aphid densities. The nutritional content of plants and aphids was also measured. As N fertilization increased, so did the nutrient content (total energy) of aphids and this resulted in declining rates of aphid consumption by beetles at higher aphid densities. Females in the 110 N treatment, and males in all treatments, responded to aphids with a type II functional response (decelerating consumption at higher densities), but females in the 160 and 210 ppm N treatments exhibited a type III response (consuming a declining proportion of available aphids at high densities). Beetles fed aphids from the 110 N treatment consumed more prey in both assays than did those fed aphids from the 210 N treatment. Beetle searching time, handling time, and duration of digestive pauses all increased at high levels of N fertilization, especially for females. The results indicate that heavy N fertilization can increase prey nutritional quality to the point where it alters predator foraging and feeding behavior, resulting in slower rates of prey consumption and longer prey handling times.

Differential Change Patterns of Main Antimicrobial Peptide Genes During Infection of Entomopathogenic Nematodes and Their Symbiotic Bacteria.

The expression of antimicrobial peptides (AMPs) as the main humoral defense reactions of insects during infection by entomopathogenic nematodes (EPNs) and their symbiont is addressed herein. Three AMPs, attacin, cecropin, and spodoptericin, were evaluated in the fifth instar larvae of Spodoptera exigua Hübner (beet armyworm) when challenged with Steinernema carpocapsae or Heterorhabditis bacteriophora. The results indicated that attacin was expressed to a greater extent than either cecropin or spodoptericin. While spodoptericin was expressed to a much lesser extent, this AMP was induced against Gram-positive bacteria, and thus not expressed after penetration of Xenorhabdus nematophila and Photorhabdus luminescens. Attacin and cecropin in the larvae treated with S. carpocapsae at 8 hr post-injection (PI) attained the maximum expression levels and were 138.42-fold and 65.84-fold greater than those of larvae infected with H. bacteriophora, respectively. Generally, the ability of H. bacteriophora to suppress attacin, cecropin, and spodoptericin was greater than that of S. carpocapsae. According to the results, the expression of AMPs by Sp. exigua larvae against S. carpocapsae was determined in the 4 statuses of monoxenic nematode, axenic nematode, live symbiotic bacterium, and dead symbiotic bacterium. The expression of attacin in larvae treated with a monoxenic nematode and live bacterium at 8 and 2 hr PI, respectively, were increased to the maximum amount. Live X. nematophila was the strongest agent for the suppression of attacin. The expression of cecropin against monoxenic nematodes and live symbiotic bacteria at 8 and 4 hr PI, respectively, reached the maximum amount while the expression levels of attacin and cecropin for axenic nematodes were lesser and stable. The results highlighted that the ability of P. luminescens in AMPs suppression was much more than X. nematophila. The results also showed that the effect of symbiotic bacterium in suppressing attacin and cecropin expression was greater than that of a monoxenic nematode; this result provided deep insight into the expression pattern parallels and fluctuations of the main AMPs during nematode infection.

Are Entomopathogenic Nematodes Effective Biological Control Agents Against the Carob Moth, Ectomyelois ceratoniae?

The carob moth (Ectomyelois ceratoniae) is the key pest of pomegranate, which causes a significant percentage of losses in pomegranate orchards and warehouses of Iran annually. The pest larvae are characterized by displaying a cryptic behavior within the fruit, which avoids most routine control techniques, especially chemical method. The low efficiency of traditional measurements and also the rich species diversity of natural enemies within the infested fruits highlight the necessity of exploring effective control methods, especially environmental friendly approaches. Entomopathogenic nematodes (EPNs) are a group of biological control agents that actively search for the host, including those in a cryptic habitat like the carob moth larvae within infested fruits. Here, we assumed that treatment of the infested and dropped fruits with EPNs may provide new insight into the management of the carob moth. Three species of EPNs, Steinernema feltiae, S. carpocapsae, and Heterorhabditis bacteriophora were selected and used in a series of in vitro and in vivo experiments. In preliminary assays, the EPNs species were used with different concentrations of infective juveniles (IJs) (0, 1, 5, 10, 25, and 50 IJ/larvae) in 2-cm diam. plates. The mortality rates of the laboratory tests were 79.75% and 76.5% for S. feltiae and S. carpocapsae, corresponded to LC50 value of 2.02 IJ/larva for S. feltiae and 2.05 IJ/larva for S. carpocapsae. On the contrary, H. bacteriophora demonstrated low virulence on the pest larvae in petri tests with a LC50 = 426.92 IJ/larva. Hence, both Steinernema species were selected for subsequent experiments. The penetration rate for S. feltiae and S. carpocapsae into the hemocoel of the pest was 43% and 31%, respectively, and the corresponding reproduction rate was 15,452 IJ/larva for S. feltiae and 18,456 IJ/larva for S. carpocapsae. The gathered data from those in vitro tests were used for a field assay. Different concentrations (5, 10, 50, 100, and 160 IJ/cm2 of the arena) of S. feltiae and S. carpocapsae were applied in the field test. The mean mortality results from the last test were 10.89% and 26.65% for S. feltiae and S. carpocapsae, respectively. Finally, we found that these low virulence rates of the nematodes were attributed to inhibitory/repellency effects of saprophytic fungi within the infested pomegranates, a usual status of the infested fruits in autumn or winter seasons. Future work on additional EPN populations more adapted to the extreme conditions of the pomegranate production area in Iran may provide sufficient evidence to continue the further investigation on the best EPN species populations and advanced formulations with high durability.

Pathogenicity of Two Species of Entomopathogenic Nematodes Against the Greenhouse Whitefly, Trialeurodes vaporariorum (Hemiptera: Aleyrodidae), in Laboratory and Greenhouse Experiments.

The greenhouse whitefly Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) is a polyphagous pest in greenhouse crops. The efficacy of two entomopathogenic nematodes (EPN), Steinernema feltiae and Heterorhabditis bacteriophora, as biological control agents against T. vaporariorum was evaluated using two model crops typical of vegetable greenhouse productions: cucumber and pepper. Laboratory tests evaluated adults and second nymphal instars for pest susceptibility to different EPN species at different concentrations of infective juveniles (IJ; 0, 25, 50, 100, 150, 200, and 250 IJ per cm(2)); subsequent greenhouse trials against second nymphal instars on cucumber and pepper plants evaluated more natural conditions. Concentrations were applied in combination with Triton X-100 (0.1% v/v), an adjuvant for increasing nematode activity. In laboratory studies, both life stages were susceptible to infection by the two nematode species, but S. feltiae recorded a lower LC50 than H. bacteriophora for both insect stages. Similarly, in greenhouse experiments, S. feltiae required lower concentrations of IJ than H. bacteriophora to reach the same mortality in nymphs. In greenhouse trials, a significant difference was observed in the triple interaction among nematode species × concentration × plant. Furthermore, the highest mortality rate of the second nymphal instars of the T. vaporariorum was obtained from the application of S. feltiae concentrated to 250 IJ/cm(2) on cucumber (49 ± 1.23%). The general mortality caused by nematodes was significantly higher in cucumber than in pepper. These promising results support further investigation for the optimization of the best EPN species/concentration in combination with insecticides or adjuvants to reach a profitable control of this greenhouse pest.

Incidence of genitourinary cancers in the Islamic Republic of Iran: a survey in 2005.

We here report the incidence of different types of genitourinary cancers among the Iranian population according to the records of the Iran Ministry of Health and Medical Education. In a population-based cancer-registry study in 2005, all recorded data in pathology laboratories, freestanding cancer clinics and treatment centers, physician offices, and other state central registries were obtained with the assistance of Iran Universities of Medical Sciences and sent to the Diseases Management Center in the Health Ministry. The prevalences of urological cancers were as follows: bladder cancer 48.3%; prostate cancer 33.4%; renal cell carcinoma 10.3%; renal pelvis and ureter cancer 0.75%; testicular cancer 6.15%; penile cancer 0.15%; urethral cancer 0.45%; and other unspecified urinary cancers 0.43%. The male to female ratios for the various common urological cancers varied between 1.69 (renal cell carcinoma) and 7.75 (unspecified urinary cancers). The incidence of prostate cancer among our population was dramatically higher than in other countries of Asia. However, bladder cancer was found to be the commonest of the genitourinary cancers, especially in elderly patients, among our population.

Diagnostic application of flexible cystoscope in pelvic fracture urethral distraction defects.

INTRODUCTION: The aim of this study was to evaluate the diagnostic value of antegrade flexible cystoscopy in pelvic fracture urethral distraction defects (PFUDD). MATERIALS AND METHODS: Between 1999 and 2004, a total of 111 patients with PFUDD were evaluated by antegrade flexible cystoscopy. The flexible cystoscope was introduced into the posterior urethra and the area was evaluated for any probable fistula, false passages, or displacement of the posterior urethra. For preventing misalignment, flexible cystoscope was also used during the urethroplasty to open the posterior urethra at its exact distal point. RESULTS: Posterior urethra ended distal to the external sphincter in 16 patients (14.4%). Five (4.5%) and 9 (8.1%) patients had severe displacement of the posterior end of the urethra and bladder neck false passage, respectively. Prostatic urethrorectal fistula was detected in 1 patient. Another 1 patient had bladder rhabdomyoma. CONCLUSION: Flexible cystoscopy is a valuable procedure in the evaluation of the bladder, the bladder neck, and the posterior urethra in patients with urethral distraction defects and complements voiding cystography before the surgery. It is also helpful for showing the exact distal point of the proximal urethra during urethroplasty in cases with displaced posterior urethra.

Predation by Allothrombium pulvinum on the spider mites Tetranychus urticae and Amphitetranychus viennensis: predation rate, prey preference and functional response.

The deutonymphs of Allothrombium pulvinum Ewing (Acari: Trombidiidae) are among the most important natural enemies of spider mites in North, North East and West Iran. In this study, maximum predation rate and preference experiments were conducted with A. pulvinum deutonymphs on apple leaf discs, to determine their preference for either of two spider mite species: Amphitetranychus viennensis (Zacher) and Tetranychus urticae Koch (Acari: Tetranychidae). Maximum predation rate tests showed that the predatory mite consumed more eggs and females of T. urticae than of A. viennensis. Furthermore, the Manly's preference index for eggs and females of T. urticae confirmed that T. urticae were the preferred prey. The functional response of A. pulvinum deutonymphs on females of T. urticae was examined over a 24-h period. Predation of A. pulvinum deutonymphs presented with females of T. urticae followed a type III functional response. Estimated handling time for the predatory mites was 4.51 h and attack coefficient b, which describes the changes in attack rate with prey densities in a type III functional response, was 0.021.

Host preference by Allothrombium pulvinum (Acari: Trombidiidae) larvae on aphids: Macrosiphum rosae, Aphis gossypii and Hyalopterus amygdali (Homoptera: Aphididae).

In this study aphid-plant association and its effect on host preference of parasitic Allothrombium pulvinum larvae was examined with multiple-choice tests. Host species selection, host size selection and superparasitism with mite larvae were studied with two-choice tests. Three aphid species were used: Macrosiphum rosae, Aphis gossypii and Hyalopterus amygdali. In multiple-choice tests, larvae of A. pulvinum showed no significant preference for any aphid-plant association when given M. rosae on rose, A. gossypii on cucumber and H. amygdali on apricot simultaneously. Two-choice tests showed that larval mites preferred H. amygdali to A. gossypii, but had no preference when offered a choice between A. gossypii and M. rosae or between H. amygdali and M. rosae. In host size selection and superparasitism tests, significantly more mites selected the larger host (M. rosae). Furthermore, parasitised H. amygdali were preferred to unparasitised ones.