222 research outputs found

    Report of Telenomus chrysopae (Hym.: Scelionidae) from Iran

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    در تحقیقی که به منظور شناسایی دشمنان طبیعی شته‌ها در سال‌های 1384-1383در اصفهان انجام شد، زنبور پارازیتوئید Telenomus chrysopae Ashmead از خانواده‌ی Scelionidae به عنوان پارازیتوئید تخم بالتوری C‏hrysoperla sp. (Neur.: Chrysopidae) مورد شناسایی قرار گرفت. این زنبور که برای اولین بار از ایران گزارش می‌شود، قبلاً از آمریکای شمالی و اروپا گزارش شده است

    Schottkyjeve diode proizvedene na elektro-kemijski raslim nano- i mikro-stapićima

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    Aligned ZnO nanorods grown on polycrystalline substrates have promising optoelectronic applications. Novel samples with such structures were electrodeposited on stainless foil from a ZnCl2 route. Well-aligned and free-standing hexagonal nanorods with 100 nm diameter and closely-packed microrods with a diameter above 1 µm could be grown normal to the substrate. The optical transition energies (absorption and emission) of samples were determined by transmittance and photoluminescence spectroscopy. We report on the fabrication of high-quality AgSchottky diodes formed on the oxygen-treated (002) facets of microrods. Diodes with a large barrier height (1.1 eV), low saturation current density (1.3 pA/cm2 ) and high rectification factor (5 × 106 at ±3 V) were fabricated. The concentration and mobility of free electrons in oxygen-treated microrods were measured as 1.4 × 1014 cm−3 and 1.2 cm2V−1 s −1 , respectively.Poredani nanoštapići ZnO, narasli na polikristalnoj podlozi, mogli bi naći primjene u optoelektroničkim napravama. Pripremili smo nove uzorke takvih naprava elektro-taloženjem na listiće nerđajućeg čelika primjenom ZnCl2. Postigli smo dobro odvojene i poredane heksagonalne nano-štapiće promjera 100 nm i gusto poredane mikro-štapiće promjera većeg od 1 µm, narasle okomito na podlogu. Primjenom propusne i fotoluminescentne spektroskopije odredili smo (apsorpcijske i emisijske) prijelazne energije uzoraka. Izvješćujemo o izradi visoko-kvalitetnih Ag-Schottky dioda izvedenih na (002) plohama mikro-štapića nakon obrade kisikom. Načinili smo diode s visokim protunaponom (1.1 eV), malom gustoćom struje zasićenja (1.3 pA/cm2 ) i velikim faktorom ispravljanja (5 × 106 na ±3 V). Odredili smo koncentraciju i pokretljivost slobodnih elektrona u kisikom-obrađenim mikro-štapićima od 1.4 × 1014 cm−3 odnosno 1.2 cm2V−1 s −1

    A survey of alfalfa aphids and their natural enemies in Isfahan, Iran, and the effect of alfalfa strip-harvesting on their populations

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    During a two-year (2004-2005) survey of alfalfa aphids and their natural enemies in Isfahan, a total of four aphid species and 58 species of their natural enemies comprised of 45 predatory species, 11 parasitoid species and two species of parasitic mites were collected and identified. Moreover, five hyperparasitoid species were collected. On each sampling date, six 20-sweep samples were taken using a 38cm-diameter sweep-net and also six 20-stem were sampled. The results showed that the mean percent of Hippodamia variegata Goeze, Nabis spp., Deraeocoris spp., Orius spp., Geocoris spp. and aphid parasitoids in strip-harvested field were 38%, 95%, 119%, 57%, 100% and 122%, respectively; higher than those in conventionally-harvested field. In contrast, the mean percent of Acyrthosiphon pisum (Harris) and Therioaphis trifolii (Monell) forma maculata (Buckton) were 24% and 28%, respectively; lower in strip-harvested field than in conventionally-harvested field

    An investigation on alfalfa aphids and their parasitoids in different parts of Iran, with a key to the parasitoids (Hemiptera: Aphididae; Hymenoptera: Braconidae: Aphidiinae)

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    In the current study some information is presented about the distribution and associations between alfalfa aphids and their parasitoids in different regions in 11 provinces of Iran, as well as an identification key to the parasitoids. The main aphids were Therioaphis trifolii maculata (Buckton) and Acyrthosiphon pisum (Harris) followed by Aphis craccivora Koch and Acyrthosiphon kondoi Shinji. The distribution pattern of these aphids showed a discrepancy in different regions. Therioaphis trifolii maculata was almost distributed in all studied areas, but A. craccivora mostly distributed in lower regions including the deserts of the east and central parts of Iran. Acyrthosiphon pisum and A. kondoi were mainly occurred in higher altitude regions.Trioxys complanatus Quilis and Praon exsoletum (Nees) were found to be specific parasitoids of T. trifolii maculata, and collected, with a few exceptions, in all studied regions. The species of Acyrthosiphon were mainly attacked by Aphidius ervi Haliday followed by A. smithi Sharma & Subba Rao and A. eadyi Starý, Gonzalez & Hall. Lysiphlebus fabarum (Marshall) was the common parasitoid of A. craccivora, but Ephedrus persicae Froggatt locally found to show host specificity on this aphid. Praon volucre (Haliday) was occasionally found to attack A. pisum and A. craccivora, but the other parasitoids including Aphidius colemani Viereck, Lysiphlebus confusus Tremblay & Eady and Diaeretiella rapae (McIntosh) were only reared from A. craccivora. Considering the occurrence of alfalfa aphids together with their parasitoids in almost all studied areas, it seems that more attention should be paid to the parasitoids of alfalfa aphids, especially the specific ones, along with other control methods in an integrated pest management programme

    Chromogenic in situ hybridisation test for breast cancer patients with equivocal IHC results - A study from Iran

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    Background: HER2/neu overexpression on cell membranes of breast cancer cells is due to HER2/neu gene amplification and it is important to identify potential candidates for anti HER2 therapy with trastuzumab. IHC, FISH and CISH are standard FDA approved assays currently used to determine HER2 status in routine practice. The aim of this study was to determine HER2 gene amplification, using the CISH method in breast carcinoma samples which had IHC +2 reactions. Materials and Methods: This study was conducted from 2008-2010 using 334 consecutive breast carcinoma samples referred from local laboratories to Mehr Hospital. CISH assays were performed for all cases, and IHC tests were also done for determining efficacy and accuracy of local labs. HER2 status in local IHC tests was compared with central IHC and CISH results. Results: Of 334 breast cancer patients, 16 were negative for HER2 IHC (0, +1), 201 cases were equivocal (+2), and 31 positive (+3). Of 334 referral cases, 88 were CISH positive (26.3) and 246 were CISH negative (73.7). Of 201 IHC +2 cases, HER2 gene amplification was observed in 42 cases (kappa: 0.42). A 29.9 concordance was found between local IHC and central IHC. Sensitivity and specificity of local IHC were 90 and 53.8, respectively. Conclusions: Low accuracy of IHC results in local labs was associated with the following factors: using former FDA-approved criteria for HER2 interpretation, utilizing non-validated kits, and lack of any quality assurance program. Therefore, following the new 2014 ASCO/CAP guideline and comprehensive quality assurance should be implemented to ensure accuracy of HER2 testing

    Properties of Pt Schottky Type Contacts On High-Resistivity CdZnTe Detectors

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    In this paper we present studies of the I-V characteristics of CdZnTe detectors with Pt contacts fabricated from high-resistivity single crystals grown by the high-pressure Brigman process. We have analyzed the experimental I-V curves using a model that approximates the CZT detector as a system consisting of a reversed Schottky contact in series with the bulk resistance. Least square fits to the experimental data yield 0.78-0.79 eV for the Pt-CZT Schottky barrier height, and <20 V for the voltage required to deplete a 2 mm thick CZT detector. We demonstrate that at high bias the thermionic current over the Schottky barrier, the height of which is reduced due to an interfacial layer between the contact and CZT material, controls the leakage current of the detectors. In many cases the dark current is not determined by the resistivity of the bulk material, but rather the properties of the contacts; namely by the interfacial layer between the contact and CZT material.Comment: 12 pages, 11 figure

    First record of Pediobius metallicus (Hym.: Eulophidae) from Iran

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    در این بررسی، زنبور Pediobius metallicus (Nees) به‌عنوان پارازیتویید مگس Liriomyza sp. (Dip.: Agromyzidae) از شهرستان زابل )استان سیستان و بلوچستان( جمع‌آوری و شناسایی شد. این زنبور برای فون حشرات ایران رکورد جدیدی محسوب می‌شود

    Review of invasive grapevine aphid, Aphis illinoisensis Shimer, and native parasitoids in the Mediterranean (Hemiptera, Aphididae; Hymenoptera, Braconidae, Aphidiinae)

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    A summary of the study of Aphis illinoisensis Shimer on grapes, Vitis vinifera in the Mediterranean area brings references and new findings on its distribution in Crete/Greece, Turkey, Northern Cyprus, Malta, Israel, Montenegro, Tunisia, Algeria and Libya. Parasitoids of A. illinoisensis were only occasionally found (Aphidius matricariae Hal. - Cyprus, Turkey, Greece; Aphidius colemani Viereck - Libya; Lysiphlebus testaceipes Cress. - Algeria). Of the native species, i.e. A. colemani, and others similar to the native species, L. testaceipes seem to be a promising biocontrol agent within the framework of an ecologically friendly management in the area. Given the evidence of its expansion, A. illinoisensis is expected to expand further in several directions from the recently documented invaded area to all the grape-growing areas of the Mediterranean and even those of South-Eastern and Central Europe
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