Protein hydrolysates supplement in the nutrient solution of soilless grown fresh peppermint and spearmint as a tool for improving product quality

7openInternationalInternational coauthor/editorThe present study investigated the potential of fresh peppermint (Mentha × piperita L.) and spearmint (Mentha spicata L.) production on a floating raft system combined with a commercial protein hydrolysate supplement (Amino16®) in a nutrient solution aiming to improve plant product quality. Three levels of the protein hydrolysate solution (0, 0.25 and 0.50%) were added in the nutrient solution, and the plants were harvested after twenty-four days. Plant growth characteristics were recorded, and nutritional, essential oil and polyphenolic composition were determined in fresh tissue. The addition of protein hydrolysates did not affect the fresh or dry weight but reduced plant height. Nitrate content significantly decreased, while total chlorophyll and essential oil content increased in both species. Moreover, the protein hydrolysate solution further increased total antioxidant capacity, total soluble phenol and carotenoid contents in spearmint plants, while it did not affect the essential oil and polyphenolic composition in both species. In conclusion, protein hydrolysates solution may be added in the nutrient solution, to improve the quality of peppermint and spearmint grown in a floating system, without adverse effects on crop yield or the essential oil and polyphenolic profile.openAktsoglou, D.; Kasampalis, D.; Sarrou, E.; Tsouvaltzis, P.; Chatzopoulou, P.; Martens, S.; Siomos, A.Aktsoglou, D.; Kasampalis, D.; Sarrou, E.; Tsouvaltzis, P.; Chatzopoulou, P.; Martens, S.; Siomos, A

Performance comparison of LS, LMMSE and Adaptive Averaging Channel Estimation (AACE) for DVB-T2

© 2015 IEEE. In this paper the performance of the Adaptive Averaging Channel Estimator (AACE-LS) which is a modified Least Square (LS) estimator and the AACE-LMMSE which is a modified Linear Minimum Mean Error (LMMSE) estimator, are compared with respect to the conventional LS and the LMMSE estimators. The AACE is an estimator which is based on the averaging of the last N Scattered Pilots (SP) from the DVB-T2 model carried in the received OFDM symbols. The proposed method could in general be applied to any pilot based estimator. The noise introduced by the channel is considered as Additive White Gaussian Noise (AWGN) with zero mean and thus an averaging process is used to eliminate it. The estimator adaptively follows the fluctuations of the amplitude envelope in the time domain and adapts the size of the buffer N, with respect to the coherence time (Tc). Finally, based on the averaged estimated channel, the LS or the LMMSE equalizer is applied to the received signal in the frequency domain. Simulations clearly show that the performance of the AACE-LS is superior to the conventional LS estimator and is near to the performance of the LMMSE with no need of a prior knowledge of the statistics and the noise of the channel and thus if the channel is unknown to the receiver, the AACE is a good choice

Designing AfriCultuReS services to support food security in Africa

ABSTRACT: Earth observation (EO) data are increasingly being used to monitor vegetation and detect plant growth anomalies due to water stress, drought, or pests, as well as to monitor water availability, weather conditions, disaster risks, land use/land cover changes and to evaluate soil degradation. Satellite data are provided regularly by worldwide organizations, covering a wide variety of spatial, temporal and spectral characteristics. In addition, weather, climate and crop growth models provide early estimates of the expected weather and climatic patterns and yield, which can be improved by fusion with EO data. The AfriCultuReS project is capitalizing on the above to contribute towards an integrated agricultural monitoring and early warning system for Africa, supporting decision making in the field of food security. The aim of this article is to present the design of EO services within the project, and how they will support food security in Africa. The services designed cover the users' requirements related to climate, drought, land, livestock, crops, water, and weather. For each category of services, results from one case study are presented. The services will be distributed to the stakeholders and are expected to provide a continuous monitoring framework for early and accurate assessment of factors affecting food security in Africa.This paper is part of the AfriCultuReS project "Enhancing Food Security in African Agricultural Systems with the Support of Remote Sensing", which received funding from the European Union's Horizon 2020 Research and Innovation Framework Programme under grant agreement No. 77465

Biostimulants as a Means to Alleviate the Transplanting Shock in Lettuce

When transplanting vegetable plants in the field, the transplants undergo a small or large setback in growth, known as transplanting shock. Various practices are commonly applied to reduce the transplanting shock. In the past two decades, several studies have shown that the application of microbial and non-microbial biostimulants can enhance plant tolerance against abiotic stresses. However, there is no information on the effect of applying biostimulants at the time of transplanting in mitigating the transplanting shock of lettuce transplants in the field. Lettuce seedlings transplanted into the soil of an unheated plastic greenhouse were treated with two biostimulants, one microbial (Bactiva®) and one non-microbial (Isabion®), on the day of transplanting and after 14 and 21 days. During production, plant growth, and development, chlorophyll fluorescence and compositional parameters were determined. According to the results, the application of the non-microbial biostimulant had a significant effect on some measured parameters, with the leaves of the treated plants having a higher chlorophyll index (CCI) by 8%, as well as higher fluorescence parameters Fm/Fo, Fv/Fo, and Fv/Fm and area by 7, 10, 3, and 27%, respectively, but fewer total soluble phenols and lower fluorescence parameter ABS/RC by 7 and 26%, respectively, compared to the control untreated ones. The above may constitute some effects on the transplanting shock, without, however, being accompanied by significant effects on the number of leaves/plant, the leaf color parameters (L*, a*, b*, C*, and ho), and the chlorophyll (a, b, a + b), total carotenoid, dry matter, and nitrate content, along with the antioxidant capacity and plant fresh weight at harvest. However, a notable effect was that a greater percentage of plants at harvest had a fresh weight in the 351–400 class, while the greatest percentage of the control plants had a fresh weight in the 301–350 g class. In contrast, the application of the microbial biostimulant had no significant effect on any of the parameters determined compared to the control. Therefore, under the conditions of the present study, the effectiveness of biostimulant application at the time of transplanting on lettuce transplants is questionable

Comparison of Longley-Rice, ITU-R P.1546 and Hata-Davidson propagation models for DVB-T coverage prediction

This paper compares precision field-strength measurements taken by a Rohde & Schwarz FSH-3 portable spectrum analyzer with simulation results derived from the ITM coverage prediction model (Irregular Terrain Model), also known as NTIA-ITS Longley-Rice model, in conjunction with the 3-arc-second SRTM (Satellite Radar Topography Mission) geographical data, the propagation predictions of ITU-R Recommendation P.1546 and those of the empirical Hata-Davidson model using HAAT. ITU-R P.1546 and Hata-Davidson models exhibit higher errors at longer distances and therefore necessary corrections should be introduced in the models in order to increase propagation prediction accuracy. Especially, measurements results show that ITU-R P.1546, on average, underestimates the field strength at distances longer than 50 km. The Longley-Rice model using the terrain digital elevations is more accurate, as expected, and its results are closer to the measurement data

Test strategies for industrial testers for converter controls equipment

Power converters and their controls electronics are key elements for the operation of the CERN accelerator complex, having a direct impact on its availability. To prevent early-life failures and provide means to verify electronics, a set of industrial testers is used throughout the converters controls electronics' life cycle. The roles of the testers are to validate mass production during the manufacturing phase and to provide means to diagnose and repair failed modules that are brought back from operation. In the converter controls electronics section of the power converters group in the technology department of CERN (TE/EPC/CCE), two main test platforms have been adopted: a PXI platform for mixed analogue-digital functional tests and a JTAG Boundary-Scan platform for digital interconnection and functional tests. Depending on the functionality of the device under test, the appropriate test platforms are chosen. This paper is a follow-up to results presented at the TWEPP 2015 conference, adding the boundary scan test platform and the first results from exploitation of the test system. This paper reports on the test software, hardware design and test strategy applied for a number of devices that has resulted in maximizing test coverage and minimizing test design effort

UHF TV band spectrum and field-strength measurements before and after analogue switch-off

Measurements of UHF-TV band spectra and field-strength levels in the pre- and post-analogue switch-off periods in the cities of Thessaloniki and Skopje clearly demonstrate the much reduced spectrum occupancy, the lower signal levels, and the feasibility of digital dividend allocations to cellular operators in the 800 MHz band, as well as the feasibility of opportunistic secondary spectrum utilization in extensive parts of the spectrum. The risk of LTE-4G interference to TV services and vice-versa is also pointed out and clearly observed from spectrum measurements near a cellular base station

Designing AfriCultuReS services to support food security in Africa

Earth Observation (EO) data are increasingly being used to monitor vegetation and detect plant growth anomalies due to water stress, drought, or pests, as well as to monitor water availability, weather conditions, disaster risks, land-use/land-cover changes and to evaluate soil degradation. Satellite data are provided regularly by worldwide organizations, covering a wide variety of spatial, temporal and spectral characteristics. In addition, climate and crop growth models provide early estimates of the expected weather patterns and yield, which can be improved by fusion with EO data. The project “AfriCultuReS” is capitalizing on the above to contribute towards an integrated agricultural monitoring and early warning system for Africa, supporting decision making in the field of food security. The aim of this paper is to present the design of EO services within the project, and how they will support food security in Africa. The designed services cover the users' requirements related to climate, drought, land, livestock, crops, water, and weather. For each category of services, results from one case study are presented. The services will be distributed to the stakeholders and are expected to provide a continuous monitoring framework for early and accurate assessment of factors affecting food security in Africa