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Packet-switched unidirectional and bidirectional ring wavelength division multiplexing (WDM) networks with destination stripping provide an increased capacity due to spatial wavelength reuse. Besides unicast traffic, future destination stripping ring WDM networks also need to support multicast traffic efficiently. This article examines the largest achievable transmitter throughput, receiver throughput, and multicast through put of both unidirectional and bidirectional ring WDM networks with destination stripping. A probabilistic analysis evaluates both the nominal capacity, which is based on the mean hop distances traveled by the multicast packet copies, and the effective capacity, which is based on the ring segment with the highest utilization probability, for each of the three throughput metrics. The developed analytical methodology accommodates not only multicast traffic with arbitrary multicast fanout but also unicast and broadcast traffic. Numerical investigations compare the nominal transmission, receiver, and multicast capacities with the effective transmission, receiver, and multicast capacities and examine the impact of number of ring nodes and multicast fanout on the effective transmission, reception, and multicast capacity of both types of ring networks for different unicast, multicast, and broadcast traffic scenarios and different mixes of unicast and multicast traffic. The presented analytical methodology enables the evaluation and comparison of future multicast-capable medium access control (MAC) protocols for unidirectional and bidirectional ring WDM networks in terms of transmitter, receiver, and multicast throughput efficiency. Index Terms--Average hop distance, destination stripping, multicast, ring network, spatial wavelength reuse, wavelength division multiplexing (WDM).

Background: Gas exchange between soil and atmosphere is of great importance for greenhouse gas cycles. As gas transport in soil is generally dominated by diffusion, the soil gas diffusion coefficient (DS) is crucial to understand fluxes between soil and atmosphere. Estimating DS is still a great source of uncertainty when calculating soil gas fluxes such as soil respiration from soil gas profiles. In situ measurement of the effective exchange coefficient (Deff) not only reduces this uncertainty, but also allows to quantify non‐diffusive transport processes in addition to the purely diffusive exchange (DS), which cannot be investigated by laboratory measurements or the application of soil gas diffusivity models. Even though several methods for in situ Deff measurement exist, they often lack in the temporal resolution to identify short‐term effects on Deff or require laborious set‐ups, which makes them unsuitable for a fast and mobile application. Aims: Our objective was to test an improved profile probe for model‐based soil gas flux analyses that allows in situ monitoring of (1) soil CO2 profiles with high temporal resolution, (2) soil gas transport coefficients, including non‐diffusive transport processes, (3) soil–atmosphere CO2 flux, and (4) soil respiration profiles. Methods: We developed a CO2 profile probe with build‐in sensors that can easily be installed in soil to gain continuous CO2 concentration profiles. The probe includes the option to inject CO2 as a tracer gas to estimate Deff. To account for changes in natural CO2 concentrations in the soil, we tested two approaches: firstly, a differential approach using two probes, an injection probe and a reference probe, and secondly, a stand‐alone approach in which changes in natural CO2 concentrations are estimated by a statistical model using its main environmental drivers. The resulting tracer gas profiles were used to fit a finite element gas diffusion model to derive Deff. Using the derived Deff values and the CO2 profiles allowed calculating CO2 fluxes. The approach was tested with controlled laboratory experiments using different mineral substrates to compare the diffusivity estimates of the in situ method with laboratory measurements on soil cores. Additional laboratory experiments included artificial CO2 sources to simulate soil respiration in order to evaluate the gradient‐based estimation of soil respiration profiles. In a second step, both approaches were tested under natural conditions in the field. Results: The derived Deff values agreed well with laboratory measurements of DS and DS‐transfer functions. The artificial CO2 sources could accurately be estimated with the gradient method. In the field under calm conditions, both approaches for the estimation of the changing natural CO2 profile gave comparable results. Under windy conditions, the stand‐alone approach gave unrealistically high values, whereas the differential approach using a reference profile still gave reliable results. We observed a clear relationship between Deff and wind‐induced pressure pumping in the topsoil. The estimated surface CO2 efflux agreed well with chamber measurements. Conclusions: This new set‐up enables monitoring of diffusive and non‐diffusive soil gas exchange and soil respiration in situ with high resolution and relatively low effort. [ABSTRACT FROM AUTHOR]

Research has been conducted on the aldol products with allyl-protected hydroxy group. The conversion of these products into amino alcohols carried out via Curtius rearrangement is described.

Research has been conducted on the intramolecular Diels-Alder reaction. The thermolysis of dienals prepared in the presence of zinc metal with ethyl 2-bromo-methylacrylate has produced tricyclic cycloadducts in the intramolecular Diels-Alder reaction.

The influence by a single modification at the 3'-terminus on the enzymatic stability of the phosphodiester backbone containing therapeutic oligonucleotides and by cytosine analogues of the phenoxazine and 9-(2-aminoethoxy)-phenoxazine are investigated. Data indicate that incorporation at the 3'-terminus completely protects the oligonucleotide against 3'-exonuclease attack.

Research has been conducted on the antisense oligonucleotides which alter splicing patterns and bind target pre-mRNA with high affinity. Results demonstrate that antisense peptide nucleic acids alter IL-5R(alpha) pre-mRNA splicing similar to their counterparts of the same sequence.

Research has been conducted on the 3'-C-methylene thymidine and 5-methyluridine/cytidine H-phosphonates and phosphonamidites. The synthesis of these compounds has been carried out and their biophysical properties and target-binding affinity are described.