Insecticide Toxicity, Synergism and Resistance in Plutella xylostella (Lepidoptera: Plutellidae)

Plutella xylostella has become particularly notorious for its resistance to various insecticides. The toxicities of abamectin, hexaflumuron and indoxacarb to third instar larvae of the pest were assayed using the leaf-dipping method. The results showed that abamectin and indoxacarb with the lowest LC50 values exhibited stronger toxicity to larvae than hexaflumuron. To determine the synergism of PBO, DEM, DEF and TPP on the toxicity of tested insecticides and demonstrating possible biochemical mechanisms, an abamectin-, a hexaflu-muron- and an indoxacarb-resistant strain of P. xylostella were selected under laboratory conditions. After 10 generations of selection, the selected strains developed 14.21, 7.08, and 32.36-fold higher resistance to these insecticides, respectively. Abamectin resistance in abamectin-selected strain was suppressed with the synergists such as DEM and PBO, suggesting the involvement of monooxygeneses and glutathione S-transferase in the development of resistance in P. xylostella. Treatment with PBO and DEF significantly decreased the toxicity of hexaflumuron in the hexaflumuron-selected strain. Also, in indoxacarb-selected strain, the maximum synergism was occurred using PBO and DEF, followed by DEM and TPP. Hexaflumuron and indoxacarb synergism studies indicated in hexaflumuron resistance, monooxygenases and esterases, and in indoxacarb resistance, monooxygenases, esterases and glutathione S-transferae may be involved in the resistance mechanism

Cloudless Friend-to-Friend Middleware for Smartphones

Using smartphones for peer-to-peer communication over the Internet is difficult without the aid of centralized services. These centralized services, which usually reside in the cloud, are necessary for brokering communication between peers, and all communication must pass through them. A reason for this is that smartphones lack publicly reachable IP addresses. Also, because people carry their smartphones with them, smartphones will often disconnect from one network and connect to another. Smartphones can also go offline. Additionally, a network of trusted peers (or friends) requires a directory of known peers, authentication mechanisms, and secure communication channels. In this paper, we propose a peer-to-peer middleware that provides these features without the need for centralized services.Comment: ICETE 2018: E-Business and Telecommunications pp 199-218. Part of the Communications in Computer and Information Science book series (CCIS, volume 1118). The final authenticated publication is available online at https://doi.org/10.1007/978-3-030-34866-3_1

Temperature-dependent development of Habrobracon hebetor (Hym.: Braconidae) reared on larvae of Galleria mellonella (Lep.: Pyralidae)

The development times and the survival rates of different stages of Habrobracon hebetor Say reared on the last instar larvae of Galleria mellonella (L.) were compared at ten different constant temperatures (16 - 38 ºC). The development time of immature stages of the parasitoid, H. hebetor, decreased as the temperature increased in the range of 16 to 38 ºC. However, no larvae could survive and develop at 16 ºC. Development time from egg to adult females was the shortest (8.368 ± 0.069 days) at 35 ºC and the longest (32.667 ± 0.33 days) at 18 ºC. Egg incubation period, larval and pupal development times were significantly different at various constant temperatures. No significant difference was found between two sexes in their developmental periods from eggs to adult stage. The survival rate of the egg stage ranged between 94.90 and 100% at all temperature levels, but larval survival rates was significantly different at various temperatures. Although significant difference was found in the survival rate of pupal stage (P < 0.05), the trend of survival rate for pupae was similar to those of larvae. The relationship between temperature and the developmental rate of the parasitoid well described by linear regression model (R2 = 0.89, P = 0.0001, at the egg stage and R2 = 0.95, P = 0.0001, at the egg-adult stage). The lowest threshold temperature was obtained for all developmental stages of the parasitoid. Degree-days requirements (DD) for egg, larva, pupa and egg-female stages were 22.73, 56.82, 109.89 and 188.68, respectively. The results in this study showed that the temperature range between 25 and 32 ºC provide a favourable condition for mass rearing of this parasitoid

Biology and demography of Trissolcus basalis (Hym.: Scelionidae) on eggs of two different hosts

A study was taken up to investigate the biological and population attributes of Trissolcus basalis (Wollaston) on eggs of Eurygaster integriceps Puton (EI) and Graphosuma lineatum (L.) (GL). First, immature development, time of adult eclosion, offspring sex ratio and rate of emergence were recorded by random selection of 25 parasitized egg masses of each host (350 eggs with 0-4 h old) separately at 25 ± 0.5 °C, 65 ± 5% RH and 16: 8 L: D. In addition, percent parasitism, immature survival rate, adult longevity and first 10 days fecundity of females were calculated using 25 newly emerged pairs (0-4 h) confined in tubes and provided with two masses of respected host eggs daily under the same conditions till they died. Results revealed that T. basalis males had significantly shorter development period (11.75 ± 0.058 and 12.57 ± 0.96 d on EI and GL eggs, respectively) compared to that of females (12.62 ± 0.06 and 13.72 ± 0.69 d on eggs of EI and GL, respectively). Similarly, it was noticed that malesâ longevity (54.72 ± 1.63 d) on EI eggs was significantly higher compared to their sibling females (43.16 ± 2.045 d) and male and female wasps on GL eggs which had significantly shorter longevity. In general, T. basalis reared on EI eggs had significantly longer oviposition period (39 ± 1.79 d), higher fecundity (292.4 ± 11.14 egg/female) and greater % parasitism (84.09 ± 1.56%) when compared with those on GL eggs. Moreover, immature survival rate was 82 and 64 % for wasp reared on EI and GL eggs, respectively. Finally, rm, λ and R0 were 0.316 and 0.224 d-1, 1.372 and 1.252 d-1 and 118.5 and 51.08 f/f/gen for wasps on EI and GL eggs, respectively. The population age distribution demonstrated that, totally, 95-98 and 2-5 % of the population were immature and adult stages for both hosts

Prompt attention of the diagnostic medical imaging centers in Tehran: An experience of people with physical disability

Background: Nowadays, change in the pattern of diseases to chronic has been with increasing use of medical imaging services. People with physical disability require continuous diagnostic and therapeutic services. Objectives: This study aimed to measure the waiting time for receiving medical imaging services and to examine sociodemographic factors associated with the poor experience of these people. Patients and Methods: In a cross-sectional study to assess the responsiveness of comprehensive rehabilitation centers in Tehran in 2016-2017, 610 people with physical disabilities who were referred to 10 comprehensive physical rehabilitation centers for rehabilitation services were asked whether they had used medical imaging services during their rehabilitation. The 477 participants (218 women) with positive response consisted the sample of this study. A checklist was used for data collection. T test, Chi-Square and Multiple Logistic Regression Model were used for analytical reports. Results: Poor experience in prompt attention of centers was reported by 26 of public diagnostic service users while 16 of private sector users and 21.2 by total sample. Waiting time for appointment and waiting time at the center were significantly longer in public medical imaging centers compared to the private sector (P < 0.05). Overall experience of public service users about prompt attention was poorer than the private sector (P < 0.05). Physical status (odd ratio OR = 3.2; 95% confidence interval CI = 1.3-7.8) and duration of disability (OR = 0.28; 95% CI = 0.09-0.9) were the predictors of poor experience of respondents about prompt attention in public and private centers respectively. Conclusion: From the service users� viewpoint, private centers had better performance in prompt attention than public centers. Attention to physical condition and duration of disability in scheduling diagnostic services is recommended. © 2018, Author(s)

Predictors of poor responsiveness in physical rehabilitation centers in Tehran

Background: Responsiveness as a nonmedical, nonfinancial aspect of a health system's goals requires special attention, particularly in people with physical disabilities. This study aimed to investigate the predictors of poor responsiveness of rehabilitation centers in Tehran. Methods: A cross sectional study was conducted to investigate 610 individuals with physical disabilities who referred to 10 comprehensive rehabilitation centers in Tehran using Quota sampling in 2016-2017. The following questionnaires were used in this study: Health System Responsiveness questionnaire, recommended by World Health Organization (WHO); Activities of Daily Living (ADL); and Instrumental Activity of Daily Living (IADL). Multiple logistic regression models were used to determine the sociodemographic characteristics (sex, age, perceived social class, etc.), self-assessed health, and physical functioning (eg, Instrumental Activities of Daily Living (IADL) as predictors of poor responsiveness in comprehensive rehabilitation centers of Tehran. Results: The mean years of education of respondents was 12.57 (SD=5.07). The majority of the participants perceived themselves as belonging to the middle class. Among the participants, 17.1% were completely dependent in their instrumental activities of daily living (IADL). Respondents who were not satisfied with their health insurance accounted for 40.2% of the sample. Also, 20.9% of the participants reported poor responsiveness. Based on the logistic regression model, variables of education, perceived social class, satisfaction with health insurance, and IADL were predictors of overall poor responsiveness after adjusting other covariates. Conclusion: Level of education was a strong predictor of poor responsiveness. Insurance companies should make policies to facilitate people's access to rehabilitation services and increase customer satisfaction. Moreover, rehabilitation service providers should pay special attention to those with physical disabilities who are more severely disadvantaged. © Iran University of Medical Sciences

Cuminum cyminum methanolic extract – Fe₃O₄ nanocomposite: A novel and efficient insecticide against the potato tuber moth (Lepidoptera: Gelechiidae) to protect potatoes

Phthorimaea operculella is a significant insect pest of cultivated potatoes in tropical and subtropical regions such as Iran. Since the potato is one of the most valuable sources of human food, non-chemical control of potato pests is essential. Application of medicinal plant extracts is a low-risk alternative method to synthetic chemical insecticides. Hence, the present study was conducted to investigate a potential strategy to improve the insecticidal activity of plant extracts for efficient management of P. operculella. The insecticidal efficacy of pure methanolic extract (PME) and Fe3O4@methanolic extract (FME) of Cuminum cyminum were evaluated against the potato tuber moth under laboratory conditions. The morphological characteristics of Fe3O4@Cumin were investigated by scanning electron microscope. Magnetic properties of the samples were determined using a vibration sample magnetometer. XRD was used to prove the crystalline structure of Fe3O4@Cumin. SEM, FTIR, XRD, and VSM analyses confirmed that the methanolic extract was loaded on Fe3O4. The toxicity of PME and Fe3O4@Cumin were evaluated on one-day-old eggs and penetration the first instar larvae of P. operculella into potato tubers and leaves. The LC50 values of Cumin extract and Fe3O4@ Cumin were 961.07 and 601.48 and 496.84 and 268.82 ppm for penetrating neonate larvae to tubers and leaves, and 874.90 and 595.16 ppm for eggs, respectively. Bioassays revealed that Fe3O4@Cumin was more toxic than non-formulated Cumin methanolic extract against eggs and neonate larvae of P. operculella. The formulated methanolic extract was significantly more repellent against the pest. Our results suggested that the prepared nanocomposite could be used as a new effective tool for P. operculella management strategies to protect potatoes