Are organically grown apples tastier and healthier? A comparative field study using conventional and alternative methods to measure fruit quality

Since 1994 important supermarket chains in Switzerland successfully sell apples from verified organic production. However, in supermarkets customers often ask whether there are, apart from a more environmentally friendly production, objective arguments of inner fruit quality that justify the higher prices of organic apples. In a field study with the ‘Golden Delicious’ cultivar, we harvested fruits of 5 pairs of organic/integrated fruit farms. The orchards within the pairs were less than 1 km from each other and were similar in micro climate, soil conditions and planting system. Maximum distance between the pairs was 180 km. To measure inner fruit quality we investigated at the beginning and at the end of cold storage (i) standard parameters (firmness, sugar, malic acid, mineral elements etc.); (ii) taste parameters by repeated panel tests; (iii) components that are good for human health (phenols, selenium, fibres, vitamin C and E) and (iv) fruit «vitality quality» by holistic approaches using image forming technique (crystallisation in copper chloride, and chromatography after Pfeiffer), degradation tests and feeding preference tests with laboratory rats. All fruit samples of organic orchards had significantly firmer fruit flesh (14%) and had 15% higher taste marks than conventional ones. P-content was 31% higher (p < 0.01) in organic apples and was closely correlated with technical quality (r2 = 0.93) and sensory score (r2 = 0.69). Content of phenols (mainly flavanols) was 19% and image forming quality 60% higher in organic apples. The picture producing method distinguished 100% correctly the organic and integrated samples and was closely in line with technical quality (r2 = 0.68). The results show that organically grown apples can have an outstanding inner quality. However, for generalizable conclusions more extensive studies are necessary

DAC-Less amplifier-less generation and transmission of QAM signals using sub-volt silicon-organic hybrid modulators

We demonstrate generation and transmission of optical signals by directly interfacing highly efficient silicon-organic hybrid (SOH) modulators to binary output ports of a field-programmable gate array. Using an SOH Mach-Zehnder modulator (MZM) and an SOH IQ modulator we generate ON-OFF- keying and binary phase-shift keying signals as well as quadrature phase-shift keying and 16-state quadrature amplitude modulation (16QAM) formats. Peak-to-peak voltages amount to only 0.27 V-pp for driving the MZM and 0.41 V-pp for the IQ modulator. Neither digital-to-analog converters nor drive amplifiers are required, and the RF energy consumption in the modulator amounts to record-low 18 fJ/bit for 16QAM signaling

Mechanisms of recruitment for the retrieval of food in Amitermes evuncifer Silvestri (Isoptera: Termitidae: Termitinae)

The study revealed that there was quantitative recruitment in colonies of Amitermes evuncifer, whenever food was discovered by the scouting foragers. Discovered food stimulated the termites to accelerate their running speed, to and from the food source. Increased trail-laying activity, accelerated movement and carrying of food by the returning workers facilitated recruitment of other confederates from their nest. These activities equally directed the recruited termites to the food source. Amitermes evuncifer was observed to regulate traffic in relation to newly discovered food source. The results showed that there was rapid communication between the termites of food source within 3-4 min. It was further observed that the trail to newly found food source did not become dominant over the trail to the already existing food source. The results showed clearly the effect of food on vital activities of termite

Silicon-Organic Hybrid (SOH) and Plasmonic-Organic Hybrid (POH) integration

Silicon photonics offers tremendous potential for inexpensive high-yield photonic-electronic integration. Besides conventional dielectric waveguides, plasmonic structures can also be efficiently realized on the silicon photonic platform, reducing device footprint by more than an order of magnitude. However, nei-ther silicon nor metals exhibit appreciable second-order optical nonlinearities, thereby making efficient electro-optic modulators challenging to realize. These deficiencies can be overcome by the concepts of silicon-organic hybrid (SOH) and plasmonic-organic hybrid integration, which combine SOI waveguides and plasmonic nanostructures with organic electro-optic cladding materials

Optical interconnect with densely integrated plasmonic modulator and germanium photodetector arrays

We demonstrate the first chip-to-chip interconnect utilizing a densely integrated plasmonic Mach-Zehnder modulator array operating at 3 x 10 Gbit/s. A multicore fiber provides a compact optical interface, while the receiver consists of germanium photodetectors

Silicon-organic hybrid electro-optical devices

Organic materials combined with strongly guiding silicon waveguides open the route to highly efficient electro-optical devices. Modulators based on the so-called silicon-organic hybrid (SOH) platform have only recently shown frequency responses up to 100 GHz, high-speed operation beyond 112 Gbit/s with fJ/bit power consumption. In this paper, we review the SOH platform and discuss important devices such as Mach-Zehnder and IQ-modulators based on the linear electro-optic effect. We further show liquid-crystal phase-shifters with a voltage-length product as low as V pi L = 0.06 V.mm and sub-mu W power consumption as required for slow optical switching or tuning optical filters and devices

Silicon-Organic Hybrid (SOH) and Plasmonic-Organic Hybrid (POH) integration

Silicon-organic hybrid (SOH) and plasmonic-organic hybrid (POH) integration combines organic clectro-optic materials with silicon photonic and plasmonic waveguides, The concept enables fast and power-efficient modulators that support advanced modulation formats such as QPSK and 16QAM

Optical interconnect solution with plasmonic modulator and Ge photodetector array

We report on an optical chip-to-chip interconnect solution, thereby demonstrating plasmonics as a solution for ultra-dense, high-speed short-reach communications. The interconnect comprises a densely integrated plasmonic Mach-Zehnder modulator array that is packaged with standard driving electronics. On the receiver side, a germanium photodetector array is integrated with trans-impedance amplifiers. A multicore fiber provides a compact optical interface to the array. We demonstrate 4 × 20 Gb/s on-off keying signaling with direct detection.ISSN:1041-1135ISSN:1941-017

Cross-polarized photon-pair generation and bi-chromatically pumped optical parametric oscillation on a chip

Nonlinear optical processes are one of the most important tools in modern optics with a broad spectrum of applications in, for example, frequency conversion, spectroscopy, signal processing and quantum optics. For practical and ultimately widespread implementation, on-chip devices compatible with electronic integrated circuit technology offer great advantages in terms of low cost, small footprint, high performance and low energy consumption. While many on-chip key components have been realized, to date polarization has not been fully exploited as a degree of freedom for integrated nonlinear devices. In particular, frequency conversion based on orthogonally polarized beams has not yet been demonstrated on chip. Here we show frequency mixing between orthogonal polarization modes in a compact integrated microring resonator and demonstrate a bi-chromatically pumped optical parametric oscillator. Operating the device above and below threshold, we directly generate orthogonally polarized beams, as well as photon pairs, respectively, that can find applications, for example, in optical communication and quantum optics