Boron Fertilization of Corn in Kentucky

The need for use of boron (B) for alfalfa production has been recognized for many years in Kentucky and is presently recommended for general use as an annual topdressing on alfalfa fields. Use of B is also recommended in Kentucky for red clover fields which are to be harvested for seed. In recent years, there has been interest in use of fertilizer B for good corn production in Kentucky. Plant available B is greatly affected by soil pH and decreases with increasing soil pH. Because of this, some states recommend use of B on corn grown on soils with a pH of 6.1 or higher. Also, some commercial soil testing laboratories serving Kentucky routinely test for B, and often recommend its use for corn. This has resulted in many corn growers in Kentucky asking if they need to use B on corn

Isospin Physics in Heavy-Ion Collisions at Intermediate Energies

In nuclear collisions induced by stable or radioactive neutron-rich nuclei a transient state of nuclear matter with an appreciable isospin asymmetry as well as thermal and compressional excitation can be created. This offers the possibility to study the properties of nuclear matter in the region between symmetric nuclear matter and pure neutron matter. In this review, we discuss recent theoretical studies of the equation of state of isospin-asymmetric nuclear matter and its relations to the properties of neutron stars and radioactive nuclei. Chemical and mechanical instabilities as well as the liquid-gas phase transition in asymmetric nuclear matter are investigated. The in-medium nucleon-nucleon cross sections at different isospin states are reviewed as they affect significantly the dynamics of heavy ion collisions induced by radioactive beams. We then discuss an isospin-dependent transport model, which includes different mean-field potentials and cross sections for the proton and neutron, and its application to these reactions. Furthermore, we review the comparisons between theoretical predictions and available experimental data. In particular, we discuss the study of nuclear stopping in terms of isospin equilibration, the dependence of nuclear collective flow and balance energy on the isospin-dependent nuclear equation of state and cross sections, the isospin dependence of total nuclear reaction cross sections, and the role of isospin in preequilibrium nucleon emissions and subthreshold pion production.Comment: 101 pages with embedded epsf figures, review article for "International Journal of Modern Physics E: Nuclear Physics". Send request for a hard copy to 1/author

Fünfiiber-Drone: A Modular Open-Platform 18-grams Autonomous Nano-Drone

Miniaturizing an autonomous robot is a challenging task - not only the mechanical but also the electrical components have to operate within limited space, payload, and power. Furthermore, the algorithms for autonomous navigation, such as state-of-the-art (SoA) visual navigation deep neural networks (DNNs), are becoming increasingly complex, striving for more flexibility and agility. In this work, we present a sensor-rich, modular, nano-sized Unmanned Aerial Vehicle (UAV), almost as small as a five Swiss Franc coin - called Fünfliber - with a total weight of 18g and 7.2cm in diameter. We conceived our UAV as an open-source hardware robotic platform, controlled by a parallel ultra-low power (PULP) system-on-chip (SoC) with a wide set of onboard sensors, including three cameras (i.e., infrared, optical flow, and standard QVGA), multiple Time-of-Flight (ToF) sensors, a barometer, and an inertial measurement unit. Our system runs the tasks necessary for a flight controller (sensor acquisition, state estimation, and low-level control), requiring only 10% of the computational resources available aboard, consuming only 9mW - 13x less than an equivalent Cortex M4-based system. Pushing our system at its limit, we can use the remaining onboard computational power for sophisticated autonomous navigation workloads, as we showcase with an SoA DNN running at up to 18Hz, with a total electronics' power consumption of 271mW