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Motivation Modern genomic breeding methods rely heavily on very large amounts of phenotyping and genotyping data, presenting new challenges in effective data management and integration. Recently, the size and complexity of datasets have increased significantly, with the result that data are often stored on multiple systems. As analyses of interest increasingly require aggregation of datasets from diverse sources, data exchange between disparate systems becomes a challenge. Results To facilitate interoperability among breeding applications, we present the public plant Breeding Application Programming Interface (BrAPI). BrAPI is a standardized web service API specification. The development of BrAPI is a collaborative, community-based initiative involving a growing global community of over a hundred participants representing several dozen institutions and companies. Development of such a standard is recognized as critical to a number of important large breeding system initiatives as a foundational technology. The focus of the first version of the API is on providing services for connecting systems and retrieving basic breeding data including germplasm, study, observation, and marker data. A number of BrAPI-enabled applications, termed BrAPPs, have been written, that take advantage of the emerging support of BrAPI by many databases. Availability and implementation More information on BrAPI, including links to the specification, test suites, BrAPPs, and sample implementations is available at https://brapi.org/. The BrAPI specification and the developer tools are provided as free and open source.

This paper gives an overview on the development of microwave phototransistors within SiGe Bipolar and BiCMOS technologies. The physics and design of SiGe/Si Heterojunction Bipolar Phototransistors (HPT) are covered. A comprehensive analysis of the photodetection mechanisms and its localization into the structure is provided. After a description of the scaling rules, applications are presented in the field of Microwave-Photonics for short range and low-cost applications. Perspectives are then highlighted that includes the frequency increase, the enlargement of functionality and even on-chip optical links.

This Letter presents the impact of silicon substrate resistivity on SiGe phototransistors. SiGe phototransistors were fabricated on the commercially available SiGe/Si bipolar technology. The performances of the phototransistors fabricated based on low- and the high-resistive silicon substrate are compared. The phototransistor based on low-resistivity (LR) silicon substrate provides a responsivity of more than double compared to the phototransistor based on a high-resistivity silicon substrate that is fabricated by using the same bipolar transistor technology. The phototransistor fabricated on LR substrate exhibits low-frequency responsivity up to 1.35 A/W (at 50 MHz).

A low-cost polymer-based structure is proposed to improve the coupling between a fiber end section and photodetector active surface in optical links based on standard single-mode fiber (SSMF), which employs vertical cavity surface emitting lasers operating at 850 nm, i.e., below the SSMF cutoff wavelength. Considering receivers as small-area detectors, which are generally necessary to guarantee high-speed operation but at the same time are particularly subject to power fluctuations due to modal noise (whose impact is in turn enhanced in the presence of fiber-to-photodetector misalignment), significant achievements are demonstrated by employing the presented structure. Indeed, in the presence of a misalignment of ± 4 to ± 6 µ m , which is nowadays typically achievable, the relative optical power fluctuations due to modal noise reduce in the presented case more than four times (2.5% from more than 10%) with respect to the case of butt-coupling, which implies an increase of the same factor in the output signal-to-noise ratio at the receiver end.

To decrease cost and consumption of future wireless infrastructures, radio-over fibre systems utilising 850 nm vertical cavity surface emitting lasers and standard single-mode fibre (SSMF) are deserving particular attention in replacing the typical use of graded-index multimode fibre (GI-MMF). In the present work, a characterisation of noise and non-linearities of these links is performed, followed by an estimation of their impact on the system dynamics and the quality of the received signal. This allows to show that very good and similar performances can be obtained through the utilisation of SSMF and GI-MMF for the transmission of five long-term evolution channels with 20 MHz bandwidth, confirming that the former, by the higher diffusion and lower cost per metre of the SSMF, can be put among the leading candidates for the realisation of fourth-generation (4G) and 5G wireless networks.

A Multi-channel LTE transmission on a Radio-over-Fibre (RoF) system realized with low cost and low consumption 850nm Vertical Cavity Surface Emitting Laser (VCSEL) and Standard Single Mode Fibre (SSMF) is proposed in the framework of wireless networks fronthaul links. The performances are evaluated through the Error Vector Magnitude (EVM) comparing different distances, channels employed and modulation formats using the carrier aggregation nominal channel spacing for 20 MHz bandwidth LTE signals. The potentiality of this link is then highlighted by the maximum length achievable according to the LTE standard for 64-QAM, 256-QAM and 1024-QAM modulation formats, for which the maximum length results to be greater than 2 km, 1 km and 100 m, respectively.