Resonant conditions for Love wave guiding layer thickness

In this work we report a systematic investigation of polymer overlayer thickness in a Love wave device working at a fundamental frequency of 110MHz and at the 330MHz harmonic. At both frequencies we observe the initial reduction in insertion loss associated with a Love wave device. Significantly, we also observe a series of resonant conditions as the layer thickness is further increased. The separation of these resonances is attributed to an increase in thickness of half of the acoustic wavelength in the polymer

Pulse mode operation of Love wave devices for biosensing applications

In this work we present a novel pulse mode Love wave biosensor that monitors both changes in amplitude and phase. A series of concentrations of 3350 molecular weight poly(ethylene glycol) (PEG) solutions are used as a calibration sequence for the pulse mode system using a network analyzer and high frequency oscilloscope. The operation of the pulse mode system is then compared to the continuous wave network analyzer by showing a sequence of deposition and removal of a model mass layer of palmitoyl-oleoyl-sn-glycerophosphocholine (POPC) vesicles. This experimental apparatus has the potential for making many hundreds of measurements a minute and so allowing the dynamics of fast interactions to be observed

Using Network Analysis to Understand Knowledge Mobilization in a Community-based Organization

Background Knowledge mobilization (KM) has been described as putting research in the hands of research users. Network analysis is an empirical approach that has potential for examining the complex process of knowledge mobilization within community-based organizations (CBOs). Yet, conducting a network analysis in a CBO presents challenges. Purpose The purpose of this paper is to demonstrate the value and feasibility of using network analysis as a method for understanding knowledge mobilization within a CBO by (1) presenting challenges and solutions to conducting a network analysis in a CBO, (2) examining the feasibility of our methodology, and (3) demonstrating the utility of this methodology through an example of a network analysis conducted in a CBO engaging in knowledge mobilization activities. Method The final method used by the partnership team to conduct our network analysis of a CBO is described. Results An example of network analysis results of a CBO engaging in knowledge mobilization is presented. In total, 81 participants completed the network survey. All of the feasibility benchmarks set by the CBO were met. Results of the network analysis are highlighted and discussed as a means of identifying (1) prominent and influential individuals in the knowledge mobilization process and (2) areas for improvement in future knowledge mobilization initiatives. Conclusion Findings demonstrate that network analysis can be feasibly used to provide a rich description of a CBO engaging in knowledge mobilization activities

Comparing regional differentiation of land cover changes in natural and administrative regions of the Czech Republic using multivariate statistics

The detection and evaluations of land cover changes represent the major task for landscape transformation studies in post-communistic countries. The results of such evaluation are, however, highly influenced by spatial delimitation of monitored units as natural or administrative regions. Moreover, the objective quantitative assessment of land cover changes and their typologies in different types of regions can be hardly done by traditional map-interpretation approach. The aim of the present research was to evaluate the differences in results of land cover changes in the Czech Republic detected in natural (93 geomorphological units) and administrative (77 districts) regions using multivariate statistics. To analyse land cover (LC) changes we used STATISTICA 9 software. The application of principal component analysis (PCA), factor analysis (FA) and cluster analysis (CA) reveals the main overall trends in land cover changes in the Czech Republic. We applied PCA, CA and FA to land cover data from CORINE projects in 1990, 2000 and 2006. We analyzed LC changes in geomorphological units of Czechia as a whole. We made our calculation based on standardised data for land cover classes. The final number of variables (LC classes) used in the study was 11, drawing upon generalisation of only those land cover classes that are present in Czech landscape. For both sets of territorial units (i.e. natural and administrative), we calculated the Euclidean distance (full connections) between the cases (territorial units). The k-means method and hierarchical clustering were used for clustering. Based on these methods we set the typology of land cover changes in natural and administrative units. Finally, we assessed the differences between these typologies as regards statistical distribution of regions among the individual types. The factors influencing differences between these typologies are discussed, concluding in considerations on a role of spatial delimitation in land cover changes studies.

Deadlock checking by a behavioral effect system for lock handling

AbstractDeadlocks are a common error in programs with lock-based concurrency and are hard to avoid or even to detect. One way for deadlock prevention is to statically analyze the program code to spot sources of potential deadlocks. Often static approaches try to confirm that the lock-taking adheres to a given order, or, better, to infer that such an order exists. Such an order precludes situations of cyclic waiting for each other’s resources, which constitute a deadlock.In contrast, we do not enforce or infer an explicit order on locks. Instead we use a behavioral type and effect system that, in a first stage, checks the behavior of each thread or process against the declared behavior, which captures potential interaction of the thread with the locks. In a second step on a global level, the state space of the behavior is explored to detect potential deadlocks. We define a notion of deadlock-sensitive simulation to prove the soundness of the abstraction inherent in the behavioral description. Soundness of the effect system is proven by subject reduction, formulated such that it captures deadlock-sensitive simulation.To render the state-space finite, we show two further abstractions of the behavior sound, namely restricting the upper bound on re-entrant lock counters, and similarly by abstracting the (in general context-free) behavioral effect into a coarser, tail-recursive description. We prove our analysis sound using a simple, concurrent calculus with re-entrant locks

Tailoring the ferromagnetic surface potential landscape by a templating two-dimensional metal-organic porous network

Two-dimensional metal-organic porous networks (2D-MOPNs) have been identified as versatile nanoarchitectures to tailor surface electronic and magnetic properties on noble metals. In this context, we propose a protocol to redecorate a ferromagnetic surface potential landscape using a 2D-MOPN. Ultrathin cobalt (Co) films grown on Au(111) exhibit a well-ordered surface triangular reconstruction. On the ferromagnetic surface, the adsorbed 2,4,6-tris(4-pyridyl)-1,3,5triazine (T4PT) molecules can coordinate with the native Co atoms to form a large-scale Co-T4PT porous network. The Co-T4PT network with periodic nanocavities serves as a templating layer to reshape the ferromagnetic surface potential. The subsequently deposited C60 molecules are steered by the network porous potential and the neighboring C60 interactions. The prototype of the ferromagnetic-supported 2D-MOPN is a promising template for the tailoring of molecular electronic and spin properties

Social Capital During COVID-19: Research Case Studies from U.S. and U.K. Contexts

Our research used a case study methodology to explore how engineering students at a university in the United Kingdom and in the United States experienced social supports in the spring term(s) of 2020 when universities worldwide shifted into emergency remote teaching due to the COVID-19 pandemic. To the best of our knowledge, this is the first cross-cultural study to examine engineering students' social support during the pandemic. We administered the Undergraduate Support Survey to engineering undergraduates at both institutions. The survey collected data about students' sense of belonging and social capital, including names of individuals who provided support for their engineering education and the specific expressive and instrumental resources they utilized during the pandemic. Results revealed similarities and differences between students at the two institutions. Both groups reported friends/roommates, professors, and family members as the primary providers of support, and both reported almost the same frequency in communication with these individuals. Participants at both institutions also reported high rates of instrumental and expressive support. However, the mean response for both sense of belonging and satisfaction at the university was lower in the U.K. and the types of alters identified in the two groups showed marked differences. Our work affirms the importance of social relationships to engineering students' success and persistence

Analysis of Germanium Hydride Molecular Clusters

Isotope clusters in library electron ionization mass spectra of germanes often appear a few u lower than theoretically expected from elemental composition; for example, the dominant peak of the Ge4H10+ pattern is shifted 8 u down. This phenomenon is due to combinations of three essential components: the molecular ion GenH2n+2+ and two products of hydrogen elimination, GenH+ and Gen+. Using these components, isotope clusters can be accurately projected for germanium hydrides from Ge2H6 up to Ge5H12