The Fact of the Given From a Realist Idealist Perspective

In his well-known Mind and World and in line with Wilfrid Sellars (1991) or “that great foe of ‘immediacy’” (ibid., 127) Hegel, McDowell claims that “when Evans argues that judgments of experience are based on non-conceptual content, he is falling into a version of the Myth of the Given” (1996, 114). In this talk and on the basis of a Berkeleyio-Kantian ‘realist idealist’ world view (sect. 1) and an explication of Kant’s concept of the “given manifold” (CPR, e.g. B138; sect. 2), I will argue that Kant and Evans (1982, chs. 5.1–5.2) were indeed mistaken in their versions of the given (sect. 3), but that Sellars and his student McDowell were even more mistaken (sects. 4–5) and that, in the end, there would appear to be a non-conceptual and (thus) non-propositional and essentially (Kantio-)Schopenhauerian given (1816, ch. 1) in perceptual experience from which we unconsciously (Helmholtz 1867, ch. 26) and automatically infer to our first perceptual beliefs

Telecommunications in cometary environments

Propagation effects on telecommunications in a cometary environment include those due to dust, the inhomogeneous plasma of the coma and tail, and ionization generated by impact of neutral molecules and dust on the spacecraft. Attenuation caused by dust particles is estimated to be on the order of 10 to the minus 5th power dB for the Halley Intercept Mission. Ionization generated by impact on the spacecraft is estimated to result in an electron content of 10 to the 12th power to 10 to the 13th power el/sq meters (3 eV electrons) along the telecommunications path. An estimate of the electron content due to Comet Halley itself is 10 to the 16th power to 10 to the 17th power el/sq meters, compared to a content of 10 to the 16th power to 10 to the 18th power el/sq meters for the Earth's ionosphere and 10 to the 17th power to 10 to the 18th power el/sq meters for the interplanetary medium. The electron content of the plasma near Comet Halley will cause excess range delay, and a Doppler shift of the signal from the spacecraft will occur in propagation to the rate of change of the path electron content. It is recommended that S and X down-link frequencies by employed to monitor the path electron content and amplitude scintillation and spectral broadening of the received signals. These measurements will provide a quantitative base of knowledge that will be valuable for radio science and telecommunications system design purposes

Protective vaccination in the horse against _Streptococcus equi_ with recombinant antigens

_Streptococcus equi_ subspecies _equi_ (_S. equi_) is a clonal, equine host-adapted pathogen of global importance that causes a highly contagious suppurative lymphodendopathy of the head and neck, more commonly known as Strangles. The disease is highly prevalent, can be severe and spread easily by visibly infected animals or by carrier animals that show no clinical signs of disease. Antibiotic treatment is usually ineffective. However, the majority of horses develop immunity to re-infection, suggesting that vaccination should be a feasible way to prevent the infection. Live attenuated vaccine strains of _S. equi_ are available but adverse reactions have been reported and they suffer from a short duration of immunity. Thus, a safe and effective vaccine against _S. equi_ is highly desirable. In this report, Welsh mountain ponies vaccinated with a combination of seven recombinant _S. equi_ proteins, were significantly protected from experimental infection by _S. equi_, resembling the spontaneous disease. The protective antigens consisted of five surface localized proteins and two IgG endopeptidases. The results from a second vaccination trial indicate that the endopeptidases were important for good protection. The similarity of _S. equi_ to other pyogenic streptococci suggests that our findings have broader implications for the prevention of streptococcal infections

Magnetic fields in circumstellar disks: The potential of Zeeman observations

Context. Recent high angular resolution polarimetric continuum observations of circumstellar disks provide new insights into their magnetic field. However, direct constraints are limited to the plane of sky component of the magnetic field. Observations of Zeeman split spectral lines are a potential approach to enhance these insights by providing complementary information. Aims. We investigate which constraints for magnetic fields in circumstellar disks can be obtained from Zeeman observations of the $113~\mathrm{GHz}$ CN lines. Furthermore, we analyze the requirements to perform these observations and their dependence on selected quantities. Methods. We simulate the Zeeman splitting with the radiative transfer (RT) code POLARIS (Reissl et al. 2016) extended by our Zeeman splitting RT extension ZRAD (Brauer et al. 2017), which is based on the line RT code Mol3D (Ober et al. 2015). Results. We find that Zeeman observations of the $113~\mathrm{GHz}$ CN lines provide significant insights into the magnetic field of circumstellar disks. However, with the capabilities of recent and upcoming instrument/observatories, even spatially unresolved observations would be challenging. Nevertheless, these observations are feasible for the most massive disks with a strong magnetic field and high abundance of CN/H. The most restrictive quantity is the magnetic field strength, which should be at least in the order of $\sim1~\mathrm{mG}$. In addition, the inclination of the disk should be around $60\deg$ to preserve the ability to derive the line-of-sight (LOS) magnetic field strength and to obtain a sufficiently high circularly polarized flux.Comment: 15 pages, 14 figure

Propagation effects on spread-spectrum mobile satellite systems

In contrast to the situation at L-band, wide bandwidths of 500 MHz or more have been allocated for mobile satellite service at frequencies between 20 and 50 GHz. These broad bandwidths are well suited for the use of spread-spectrum. Certain system considerations about the use of such high frequencies for mobile satellite service are mentioned first, and attention is then given to propagation effects on high-frequency broad-band systems. Attenuation due to rain is a constant at 20 to 50 MHz, but would not be a serious problem if outages occurring for one to three percent of the time, depending on location, are considered to be acceptable. Clear air absorption becomes a significant factor above 40 GHz, but should not exceed 2 dB at a 10 degree elevation angle and frequencies below 40 GHz. Spread-spectrum provides a form of frequency diversity that helps to minimize the effects of multipath