Microwave Spectroscopy

Contains reports on three research projects

Resource dedication problem in a multi-project environment

There can be different approaches to the management of resources within the context of multi-project scheduling problems. In general, approaches to multiproject scheduling problems consider the resources as a pool shared by all projects. On the other hand, when projects are distributed geographically or sharing resources between projects is not preferred, then this resource sharing policy may not be feasible. In such cases, the resources must be dedicated to individual projects throughout the project durations. This multi-project problem environment is defined here as the resource dedication problem (RDP). RDP is defined as the optimal dedication of resource capacities to different projects within the overall limits of the resources and with the objective of minimizing a predetermined objective function. The projects involved are multi-mode resource constrained project scheduling problems with finish to start zero time lag and non-preemptive activities and limited renewable and nonrenewable resources. Here, the characterization of RDP, its mathematical formulation and two different solution methodologies are presented. The first solution approach is a genetic algorithm employing a new improvement move called combinatorial auction for RDP, which is based on preferences of projects for resources. Two different methods for calculating the projects’ preferences based on linear and Lagrangian relaxation are proposed. The second solution approach is a Lagrangian relaxation based heuristic employing subgradient optimization. Numerical studies demonstrate that the proposed approaches are powerful methods for solving this problem

Radio-Frequency Spectroscopy

Contains reports on three research projects

Radio-Frequency Spectroscopy

Contains reports on four research projects

Radio-Frequency Spectroscopy

Contains reports on four research projects

Thermodynamic analysis of the Quantum Critical behavior of Ce-lattice compounds

A systematic analysis of low temperature magnetic phase diagrams of Ce compounds is performed in order to recognize the thermodynamic conditions to be fulfilled by those systems to reach a quantum critical regime and, alternatively, to identify other kinds of low temperature behaviors. Based on specific heat ($C_m$) and entropy ($S_m$) results, three different types of phase diagrams are recognized: i) with the entropy involved into the ordered phase ($S_{MO}$) decreasing proportionally to the ordering temperature ($T_{MO}$), ii) those showing a transference of degrees of freedom from the ordered phase to a non-magnetic component, with their $C_m(T_{MO})$ jump ($\Delta C_m$) vanishing at finite temperature, and iii) those ending in a critical point at finite temperature because their $\Delta C_m$ do not decrease with $T_{MO}$ producing an entropy accumulation at low temperature. Only those systems belonging to the first case, i.e. with $S_{MO}\to 0$ as $T_{MO}\to 0$, can be regarded as candidates for quantum critical behavior. Their magnetic phase boundaries deviate from the classical negative curvature below $T\approx 2.5$\,K, denouncing frequent misleading extrapolations down to T=0. Different characteristic concentrations are recognized and analyzed for Ce-ligand alloyed systems. Particularly, a pre-critical region is identified, where the nature of the magnetic transition undergoes significant modifications, with its $\partial C_m/\partial T$ discontinuity strongly affected by magnetic field and showing an increasing remnant entropy at $T\to 0$. Physical constraints arising from the third law at $T\to 0$ are discussed and recognized from experimental results

Habitat determinants of golden‐headed lion tamarin (Leontopithecus chrysomelas) occupancy of cacao agroforests: Gloomy conservation prospects for management intensification

Organismal distributions in human‐modified landscapes largely depend on the capacity of any given species to adapt to changes in habitat structure and quality. The golden‐headed lion tamarin (GHLT; Leontopithecus chrysomelas) is an Endangered primate from the Brazilian Atlantic Forest whose remaining populations occupy heterogeneous landscapes consisting primarily of shade cacao (Theobroma cacao) agroforestry, locally known as cabrucas. This cash crop can coexist with high densities of native tree species and holds a significant proportion of the native fauna, but its widely extolled wildlife‐friendly status is increasingly threatened by management intensification. Although this potentially threatens to reduce the distribution of GHLTs, the main determinants of tamarin's occupancy of cabrucas remain unknown, thereby limiting our ability to design and implement appropriate conservation practices. We surveyed 16 cabruca patches in southern Bahia, Brazil, and used occupancy modeling to identify the best predictors of GHLT patch occupancy. Key explanatory variables included vegetation structure, critical resources, landscape context, human disturbance, and predation pressure. We found a negative relationship between GHLT occupancy and the prevalence of jackfruit trees (Artocarpus heterophylus), which is likely associated with the low representation of other key food species for GHLTs. Conversely, cabrucas retaining large‐diameter canopy trees have a higher probability of GHLT occupancy, likely because these trees provide preferred sleeping sites. Thus, key large tree resources (food and shelter) are currently the main drivers of GHLT occupancy within cabruca agroecosystems. Since both factors can be directly affected by crop management practices, intensification of cabrucas may induce significant habitat impacts on GHLT populations over much of their remaining range‐wide distribution

Five mucosal transcripts of interest in ulcerative colitis identified by quantitative real-time PCR: a prospective study

<p>Abstract</p> <p>Background</p> <p>The cause and pathophysiology of ulcerative colitis are both mainly unknown. We have previously used whole-genome microarray technique on biopsies obtained from patients with ulcerative colitis to identifiy 5 changed mucosal transcripts. The aim of this study was to compare mucosal expressions of these five transcripts in ulcerative colitis patients vs. controls, along with the transcript expression in relation to the clinical ulcerative colitis status.</p> <p>Methods</p> <p>Colonic mucosal specimens from rectum and caecum were taken at ambulatory colonoscopy from ulcerative colitis patients (<it>n </it>= 49) with defined inflammatory activity and disease extension, and from controls (<it>n </it>= 67) without inflammatory bowel disease. The five mucosal transcripts aldolase B, elafin, MST-1, simNIPhom and SLC6A14 were analyzed using quantitative real-time PCR.</p> <p>Results</p> <p>Significant transcript differences in the rectal mucosa for all five transcripts were demonstrated in ulcerative colitis patients compared to controls. The grade of transcript expression was related to the clinical disease activity.</p> <p>Conclusion</p> <p>The five gene transcripts were changed in patients with ulcerative colitis, and were related to the disease activity. The known biological function of some of the transcripts may contribute to the inflammatory features and indicate a possible role of microbes in ulcerative colitis. The findings may also contribute to our pathophysiological understanding of ulcerative colitis.</p

Microwave Physics

Contains reports on five research projects