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We devised a method for screening various substances for possible aphid repellency. Corn leaf aphids ( Rhopalosiphum maidis) were released in an arena and allowed to select paired green tiles coated with petroleum jelly alone or petroleum jelly containing 1% of the substance being tested. Aphids adhering to tiles were counted 24 h later. If significantly fewer aphids landed on treated tiles, the substance was considered to have potential for repelling aphids. Fifty-five substances were tested. Most showed no activity, but several including β-citronellol, farnesol, geraniol, linalool, oils distilled from several species of Artemisia and Achillea millefolia (yarrow) oil showed some promise. [ABSTRACT FROM AUTHOR]

Potato progenies in a line × tester mating design and the clonal parents were screened for field resistance to potato leafroll virus (PLRV) to determine the heritability of this trait. Twelve advanced potato clones or varieties were crossed as pistillate parents to two pollen testers. The seedling progenies and clonal parents were exposed to aphid-transmitted potato leafroll virus for two growing seasons. Cumulative infection by potato leafroll virus was determined by post-season serological indexing of foliage grown from sprouted tubers after 2 years of exposure. Narrow-sense heritability was estimated from regression of mid-parent on progeny as h² = 0.72. This estimate indicates a high level of useable genetic variance for PLRV resistance in advanced breeding materials. Although variation in resistance to PLRV appears to be a quantitative trait in susceptible and moderately resistant clones, performance of the most resistant parents suggests that genes with major effects may be present. These results are similar to the conclusions of other researchers who found one or two genes controlling the phenotypes of extreme resistance, resistance to infection, or suppression of virus titre. [ABSTRACT FROM AUTHOR]

Detecting the primordial 'B-mode' polarization of the cosmic microwave background is one of the major challenges of modern observational cosmology. Microwave telescopes need sensitive cryogenic bolometers with an overall equivalent noise temperature in the nK range. In this paper, we present the development status of large area (about 1 cm $$^{2})$$ spider-web bolometer, which imply additional fabrication challenges. The spider-web is a suspended Si $$_{3}$$ N $$_{4}$$ 1 $$\upmu $$ m-thick and 8-mm diameter with mesh size of 250 $$\upmu $$ m. The thermal sensitive element is a superconducting transition edge sensor (TES) at the center of the bolometer. The first prototype is a Ti-Au TES with transition temperature tuned around 350 mK, new devices will be a Mo-Au bilayer tuned to have a transition temperature of 500 mK. We present the fabrication process with micro-machining techniques from silicon wafer covered with SiO $$_{2}$$ - Si $$_{3}$$ N $$_{4}$$ CVD films, 0.3 and 1 $$\upmu $$ m- thick, respectively, and preliminary tests. [ABSTRACT FROM AUTHOR]

The ATHENA X-IFU development program foresees to build and characterize an instrument Demonstration Model (DM), in order to probe the system critical technologies before the mission adoption. In this respect, we are now developing the DM of the X-IFU Cryogenic AntiCoincidence Detector (CryoAC), which will be delivered to the Focal Plane Assembly development team for the integration with the TES array. Before the delivery, we will characterize and test the CryoAC DM in our CryoLab at INAF/IAPS. In this paper, we report the main results of the activities performed to improve our cryogenic test setup, making it suitable for the DM integration. These activities mainly consist in the development of a mechanical setup and a cryogenic magnetic shielding system, whose effectiveness has been assessed by FEM simulations and a measurement at warm. The preliminary performance test has been performed by means of the last CryoAC single-pixel prototype, the AC-S8 pre-DM sample. [ABSTRACT FROM AUTHOR]

The ATHENA X-ray observatory is the second large-class mission in the ESA Cosmic Vision 2015-2025 science programme. One of the two on-board instruments is the X-IFU, an imaging spectrometer based on a large array of TES microcalorimeters. To reduce the particle-induced background, the spectrometer works in combination with a cryogenic anticoincidence detector (CryoAC), placed less than 1 mm below the TES array. The last CryoAC single-pixel prototypes, namely AC-S7 and AC-S8, are based on large-area (1 cm2) silicon absorbers sensed by 65 parallel-connected iridium TES. This design has been adopted to improve the response generated by the athermal phonons, which will be used as fast anticoincidence flag. The latter sample is featured also with a network of aluminum fingers directly connected to the TES, designed to further improve the athermals collection efficiency. In this paper, we will report the main results obtained with AC-S8, showing that the additional fingers network is able to increase the energy collected from the athermal part of the pulses (from the 6% of AC-S7 up to the 26 % with AC-S8). Furthermore, the finger design is able to prevent the quasiparticle recombination in the aluminum, assuring a fast pulse rising front (L/R limited). In our road map, the AC-S8 prototype is the last step before the development of the CryoAC demonstration model, which will be the detector able to demonstrate the critical technologies expected in the CryoAC development programme. [ABSTRACT FROM AUTHOR]

The assessment of neutrino absolute mass scale is still a crucial challenge in today particle physics and cosmology. Beta or electron capture spectrum end-point study is currently the only experimental method which can provide a model-independent measurement of the absolute scale of neutrino mass. HOLMES is an experiment funded by the European Research Council to directly measure the neutrino mass. HOLMES will perform a calorimetric measurement of the energy released in the electron capture decay of the artificial isotope 163Ho. In a calorimetric measurement, the energy released in the decay process is entirely contained into the detector, except for the fraction taken away by the neutrino. This approach eliminates both the issues related to the use of an external source and the systematic uncertainties arising from decays on excited final states. The most suitable detectors for this type of measurement are low-temperature thermal detectors, where all the energy released into an absorber is converted into a temperature increase that can be measured by a sensitive thermometer directly coupled with the absorber. This measurement was originally proposed by De Rujula and Lusignoli (Nucl Phys B 219:277, 1983. 10.1016/0550-3213(83)90642-9), but only in the last decade the technological progress in detectors development has allowed to design a sensitive experiment. HOLMES plans to deploy a large array of low-temperature microcalorimeters with implanted 163Ho nuclei. In this contribution we outline the HOLMES project with its physics reach and technical challenges, along with its status and perspectives. [ABSTRACT FROM AUTHOR]

In this paper new version of the 6 Li-based neutron spectrometer for high flux environments is described. The new spectrometer was built with commercial single crystal Chemical Vapour Deposition diamonds of electronic grade. These crystals feature better charge collection as well as higher radiation hardness. New metal contacts approaching ohmic conditions were deposited on the diamonds suppressing build-up of space charge observed in the previous prototypes. New passive preamplification of the signal at detector side was implemented to improve its resolution. This preamplification is based on the RF transformer not sensitive to high neutron flux. The compact mechanical design allowed to reduce detector size to a tube of 1 cm diameter and 13 cm long. The spectrometer was tested in the thermal column of TRIGA reactor and at the DD neutron generator. The test results indicate an energy resolution of 300 keV (FWHM), reduced to 72 keV (RMS) excluding energy loss, and coincidence timing resolution of 160 ps (FWHM). The measured data are in agreement with Geant4 simulations except for larger energy loss tail presumably related to imperfections of metal contacts and glue expansion. [ABSTRACT FROM AUTHOR]

Sage Russet was released in 2009 by Oregon State University, in cooperation with the USDA-ARS and the Agricultural Experiment Stations of Idaho and Washington. It is a product of the Northwest Potato Variety (Tri-State) Development Program. Sage Russet has a medium-early maturity and produces long, somewhat flattened tubers with medium russeting of the skin. Total yields of Sage Russet are similar to those of Russet Burbank and Ranger Russet, but are significantly higher than those of Russet Norkotah. Sage Russet has significantly higher U.S. No.1 yields than Russet Burbank, Russet Norkotah, and Ranger Russet. It can be grown as an early or late crop with high U.S. No.1 yields and minimal internal defects. It achieved very high merit scores in processing and fresh market in Western Regional trials and can be considered for both markets. Sage Russet has a medium to high fertility requirements with high nitrogen use efficiency and medium storage capability. Sage Russet has moderate specific gravity and produces lighter fry color than the industry standard varieties. The color of fried strips following tuber storage at 4.4 °C and 7.2 °C is significantly lighter for Sage Russet than the control varieties, indicating good cold sweetening resistance. Chemical analyses have shown that Sage Russet has higher protein and vitamin C content than control varieties. Sage Russet is moderately resistant to early dying, early blight, and common scab, is resistant to tuber late blight, but susceptible to Fusarium wilt and is prone to shatter bruise. [ABSTRACT FROM AUTHOR]

The ATHENA observatory is the second large-class ESA mission, in the context of the Cosmic Vision 2015-2025, scheduled to be launched on 2028 at L2 orbit. One of the two planned focal plane instruments is the X-ray Integral Field Unit (X-IFU), which will be able to perform simultaneous high-grade energy spectroscopy and imaging over the 5 arcmin FoV by means of a kilo-pixel array of transition-edge sensor (TES) microcalorimeters, coupled to a high-quality X-ray optics. The X-IFU sensitivity is degraded by the particle background, induced by primary protons of both solar and cosmic rays' origin and secondary electrons. A Cryogenic AntiCoincidence (CryoAC) TES-based detector, located $$<$$ 1 mm below the TES array, will allow the mission to reach the background level that enables its scientific goals. The CryoAC is a 4-pixel detector made of Silicon absorbers sensed by Iridium TESs. We currently achieve a TRL $$=$$ 3-4 at the single-pixel level. We have designed and developed two further prototypes in order to reach TRL $$=$$ 4. The design of the CryoAC has been also optimized using the Geant4 simulation tool. Here we will describe some results from the Geant4 simulations performed to optimize the design and preliminary test results from the first of the two detectors, 1 cm $$^{2}$$ area, made of 65 Ir TESs. [ABSTRACT FROM AUTHOR]

In this paper, we explore the possibility of using transition edge sensor (TES) detectors in multi-mode configuration in the focal plane of the Short Wavelength Instrument for the Polarization Explorer (SWIPE) of the balloon-borne polarimeter Large-Scale Polarization Explorer (LSPE) for the Cosmic Microwave Background (CMB) polarization. This study is motivated by the fact that maximizing the sensitivity of TES bolometers, under the augmented background due to the multi-mode design, requires a non-trivial choice of detector parameters. We evaluate the best parameter combination taking into account scanning strategy, noise constraints, saturation power, and operating temperature of the cryostat during the flight. [ABSTRACT FROM AUTHOR]

The determination of the neutrino mass is an open issue in modern particle physics and astrophysics. The direct mass measurement is the only theory-unrelated experimental tool capable to probe such quantity. The HOLMES experiment will measure the end-point energy of the electron capture decay of $$^{163}$$ Ho, aiming at a statistical sensitivity on the neutrino mass around 1 eV/c $$^2$$ . In order to acquire the large needed statistics by keeping the pile-up contribution as low as possible, 1000 transition edge sensors will be readout simultaneously with the frequency domain readout, a multiplexing technique where the multiplex factor is only limited by the bandwidth of the available commercial fast digitizers. We outline here the HOLMES project with its technical challenges, and its status and perspectives. [ABSTRACT FROM AUTHOR]

The microcalorimeter array for a rhenium experiment (MARE) project aims at the direct and calorimetric measurement of the electron neutrino mass with sub-eV sensitivity. The design is based on large arrays of thermal detectors to study the beta decay of $$^{187}$$ Re and the electron capture of $$^{163}$$ Ho. One of the activities of the project, MARE 1 in Milan, has started in Milan using one array of 6 $$\times $$ 6 silicon implanted thermistors equipped with AgReO $$_4$$ absorbers. The purposes of MARE 1 in Milan are to achieve a sensitivity on the neutrino mass of a few eV and to investigate the systematics of $$^{187}$$ Re neutrino mass measurements, focusing on those caused by the beta environmental fine structure and the beta spectrum theoretical shape. In parallel, the MARE collaboration is performing an R&D work for producing absorbers embedded with radioactive metal $$^{163}$$ Ho. We report here the status of MARE using Re as beta source and the preliminary results obtained with $$^{163}$$ Ho. [ABSTRACT FROM AUTHOR]

Owyhee Russet (AO96160-3) originated from a cross between A89384-10 and A89512-3 in 1996. Owyhee Russet was released in 2009 by Oregon State University, in cooperation with the USDA-ARS and the Agricultural Experiment Stations of Idaho and Washington and is a product of the Northwest Potato Variety (Tri-State) Development Program. Owyhee Russet has semi-erect medium sized vines with medium to late maturity. The tubers are long, with a tan skin, medium russeting, and attractive tuber appearance for fresh market. Owyhee Russet was evaluated in several locations across the Northwest for more than 15 years. Total yield of Owyhee Russet is similar to that of Russet Burbank and Ranger Russet but significantly higher than Russet Norkotah. U.S. No.1 tuber yield of Owyhee Russet is significantly higher than Russet Burbank and Russet Norkotah, resulting in substantially higher marketable yield. Owyhee Russet tubers have significantly higher specific gravity than Russet Burbank and Russet Norkotah. Fry color following tuber storage at 4°C and 9°C is significantly lighter for Owyhee Russet than the comparison varieties. Relative strengths include high yield with a very high proportion of U.S. No.1 tubers, good tuber appearance and excellent processing quality, resistance to cold sweetening, common scab and Fusarium dry rot. Weaknesses include susceptibility to foliar and tuber late blight and susceptibility to metribuzin herbicide injury. Allelic patterns of five SSR markers have shown that Owyhee Russet has a distinctive DNA genetic fingerprint from its russet type reference varieties which are Ranger Russet, Russet Burbank, and Russet Norkotah. [ABSTRACT FROM AUTHOR]

Palisade Russet is a medium-late maturing, lightly russeted potato cultivar notable for its resistance to late blight (Phytophthora infestans) infection of foliage and tuber. Palisade Russet is suitable for processing with low tuber glucose concentrations observed following long-term storage at a temperature as low as 5.6°C with consistently acceptable fry color scores (USDA value ≤2.0) following storage at temperatures of 5.6 to 8.9°C. Reducing sugars are also maintained uniformly throughout the tuber, resulting in a low incidence of sugar ends in French fries relative to standard processing cultivars such as Russet Burbank and Ranger Russet. Palisade Russet has shown high specific gravities in western production regions of the U.S. which may limit its acceptance by the western processing industry. However, in potato production regions with inherently low specific gravities, Palisade Russet could have potential as a processing cultivar. In full-season trials conducted in Idaho, Oregon, and Washington over a 5 year period, the average total yield of Palisade Russet across all three states was very similar to yields observed for Ranger Russet and Russet Burbank. However, the U.S. No. 1 yield of Palisade Russet was 3% and 31% higher relative to Ranger Russet and Russet Burbank, respectively. In addition to late blight, Palisade Russet is also resistant to Verticillium wilt, black dot, and pink rot, and has a moderate level of resistance to net necrosis, PVY, and early blight of both the foliage and tuber. The disease resistances of Palisade Russet make it a good candidate for organic production, or for use by growers seeking reduced pesticide inputs. Palisade Russet displays a low incidence of second growth and growth cracks, especially relative to Russet Burbank, and is intermediate between Ranger Russet and Russet Burbank for incidence of hollow heart/brown center. Blackspot bruise expression for Palisade Russet is less pronounced than for either Ranger Russet or Russet Burbank, however it is slightly more susceptible to shatter bruise. Palisade Russet was released in 2011 by the USDA-ARS and the Agricultural Experiment Stations of Idaho, Oregon, and Washington, and is a product of the Pacific Northwest Potato Variety (Tri-State) Development Program. [ABSTRACT FROM AUTHOR]

We present the design, implementation and first tests of the superconducting LC filters for the frequency domain readout of spiderweb TES bolometers of the SWIPE experiment on the balloon-borne LSPE mission which aims at measuring the linear polarization of the Cosmic Microwave Background at large angular scales to find the imprint of inflation on the B-mode CMB polarization. LC filters are designed, produced and tested at the INFN sections of Pisa and Genoa where thin film deposition and cryogenic test facilities are present, and where also the TES spiderweb bolometers are being produced. [ABSTRACT FROM AUTHOR]

In the last years organic scintillators have been largely investigated in order to achieve high light yield together with good time response. Pure organic compound with high quality crystalline structure can achieve both this goals. Among a large type of organic compound, para -terphenyl (C 18 H 14 ) have proven to have practical applications as detector medium for particle physics. In this work, the characterization of different sizes high quality mono-crystal p -terphenyl samples is presented. The optical and scintillation properties (emission spectrum, light yield, attenuation length, and decay time) are investigated. Coupling a Silicon PhotoMultiplier-based readout system to the crystal, a small prototype for a high resolution TOF detector was built; the preliminary results, obtained on a 20×30×3 mm 3 sample, with dual-side read-out (Hamamatsu S10931-050P SiPMs) and irradiated with 90 Sr source, show a time resolution of 35 ps. [ABSTRACT FROM AUTHOR]

HOLMES is a new experiment to directly measure the neutrino mass with a sensitivity as low as 0.4 eV. HOLMES will perform a calorimetric measurement of the energy released in the electron capture decay of 163 Ho. HOLMES will deploy a large array of low temperature microcalorimeters with implanted 163 Ho nuclei. HOLMES baseline detector is an array of 1000 microcalorimeters each with an implanted 163 Ho activity of about 300 Bq, an energy resolution FWHM of about 1 eV at the spectrum end-point ( Q ≈ 2.5 keV), and a time resolution of about 1 μs. Matching these performances requires a careful optimization of all components, from the microcalorimeters to the signal processing algorithms. We outline here the project technical challenges and the present status of the development. [ABSTRACT FROM AUTHOR]