Chiroptical methods are widely used in structural and conformational analyses of biopolymers. The application of these methods to investigations of biofluids would provide new avenues for the molecular diagnosis of protein-misfolding diseases. In this work, samples of human blood plasma and hen egg white were analyzed using a combination of conventional and chiroptical methods: ultraviolet absorption/electronic circular dichroism (UV/ECD), Fourier transform infrared absorption/vibrational circular dichroism (FTIR/VCD), and Raman scattering/Raman optical activity (Raman/ROA). For comparison, the main components of these substances--human serum albumin (HSA) and ovalbumin (Ova)--were also analyzed by these methods. The ultraviolet region of the ECD spectrum was analyzed using the CDNN CD software package to evaluate the secondary structures of the proteins. The UV/ECD, FTIR/VCD, and Raman/ROA spectra of the substances were quite similar to those of the corresponding major proteins, while some differences were also detected and explained. The conclusions drawn from the FTIR/VCD and Raman/ROA data were in good agreement with the secondary structures calculated from ECD. The results obtained in this work demonstrate that the chiroptical methods used here can be applied to analyze not only pure protein solutions but also more complex systems, such as biological fluids.

Abstract. Current intrusion detection systems have a narrow scope. They target flow aggregates, reconstructed TCP streams, individual packets or application-level data fields, but no existing solution is capable of handling all of the above. Moreover, most systems that perform payload inspection on entire TCP streams are unable to handle gigabit link rates. We argue that network-based intrusion detection systems should consider all levels of abstraction in communication (packets, streams, layer-7 data units, and aggregates) if they are to handle gigabit link rates in the face of complex application-level attacks such as those that use evasion techniques or polymorphism. For this purpose, we developed a framework for network-based intrusion prevention at the network edge that is able to cope with all levels of abstraction and can be easily extended with new techniques. We validate our approach by making available a practical system, SafeCard , capable of reconstructing and scanning TCP streams at gigabit rates while preventing polymorphic buffer-overflow attacks, using (up to) layer-7 checks. Such performance makes it applicable in-line as an intrusion prevention system. SafeCard merges multiple solutions, some new and some known. We made specific contributions in the implementation of deep-packet inspection at high speeds and in detecting and filtering polymorphic buffer overflows.

In many workloads, most write operations performed on a file system modify only a small number of blocks. The logstructured file system was designed for such a workload, additionally with the aim of fast crash recovery and system snapshots. Surprisingly, although implemented for Berkeley Sprite and BSD systems, there was no complete implementation for the current Linux kernel. In this paper, we present a complete implementation of the log-structured file system for the Linux kernel, which includes a user-space garbage collector and additional tools. We evaluate the measurements obtained in several test cases and compare the results with widely-used ext3.

For many years, multiserver 1 operating systems have been demonstrating, by their design, high dependability and reliability. However, the design has inherent performance implications which were not easy to overcome. Until now the context switching and kernel involvement in the message passing was the performance bottleneck for such systems to get broader acceptance beyond niche domains. In contrast to other areas of software development where fitting the software to the parallelism is difficult, the new multicore hardware is a great match for the multiserver systems. We can run individual servers on different cores. This opens more room for further decomposition of the existing servers and thus improving dependability and live-updatability. We discuss in general the implications for the multiserver systems design and cover in detail the implementation and evaluation of a more dependable networking stack. We split the single stack into multiple servers which run on dedicated cores and communicate without kernel involvement. We think that the performance problems that have dogged multiserver operating systems since their inception should be reconsidered: it is possible to make multiserver systems fast on multicores.

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