Two Case Studies of Subsystem Design for General-Purpose CSCW Software Architectures

This paper discusses subsystem design guidelines for the software architecture of general-purpose computer supported cooperative work systems, i.e., systems that are designed to be applicable in various application areas requiring explicit collaboration support. In our opinion, guidelines for subsystem level design are rarely given most guidelines currently given apply to the programming language level. We extract guidelines from a case study of the redesign and extension of an advanced commercial workflow management system and place them into the context of existing software engineering research. The guidelines are then validated against the design decisions made in the construction of a widely used web-based groupware system. Our approach is based on the well-known distinction between essential (logical) and physical architectures. We show how essential architecture design can be based on a direct mapping of abstract functional concepts as found in general-purpose systems to modules in the essential architecture. The essential architecture is next mapped to a physical architecture by applying software clustering and replication to achieve the required distribution and performance characteristics

A nonet of novel species of Monanthotaxis (Annonaceae) from around Africa

As part of an ongoing revision of the genus Monanthotaxis Baill. (Annonaceae), nine new species are described and one variety is reinstated to species rank. Two new species from West Africa (Monanthotaxis aquila P.H. Hoekstra, sp. nov. and Monanthotaxis atewensis P.H. Hoekstra, sp. nov.), four new species from Central Africa (Monanthotaxis couvreurii P.H. Hoekstra, sp. nov., Monanthotaxis latistamina P.H. Hoekstra, sp. nov., Monanthotaxis tripetala P.H. Hoekstra, sp. nov. and Monanthotaxis zenkeri P.H. Hoekstra, sp. nov.), one new species from Tanzania (Monanthotaxis filipes P.H. Hoekstra, sp. nov.), one new species from the area around Maputo (Monanthotaxis maputensis P.H. Hoekstra, sp. nov.), one new species from the Comoro Islands (Monanthotaxis komorensis P.H. Hoekstra, sp. nov.) and Monanthotaxis klainei (Engl.) Verdc. var. angustifolia (Boutique) Verdc. is raised to species level leading to the replacement name Monanthotaxis atopostema P.H. Hoekstra, nom. nov. (not Monanthotaxis angustifolia (Exell) Verdc.). Complete descriptions, comparisons with related species, ecological information and IUCN conservation assessments are given for the new species. Five species were classified as critical endangered, two species as endangered, one as vulnerable and one as least concern, warranting the need of further collecting and studying those species

A new species of Monanthotaxis from Gabon with a unique inflorescence type for Annonaceae

Monanthotaxis Baillon (1890: 878) currently consists of 56 species (Rainer & Chatrou 2006) confined to tropical Africa and Madagascar and is the second most species-rich genus of Annonaceae in Africa after Uvaria Linnaeus (1753: 536). Both genera belong to the tribe Uvarieae Hooker & Thomson (1855: 91, 92). Circumscription of this tribe has recently been modified to comply with the principle of monophyly, and it now almost exclusively consists of climbing species, all from the Old World tropics (Chatrou et al. 2012). Generic circumscription within Uvarieae has been in disarray for considerable time. Delimitation of Uvaria and related genera has recently been modified based on phylogenetic relationships (Zhou et al. 2010, Zhou et al. 2009). Monanthotaxis was monophyletic in Wang et al. (2012), based on a limited sampling of seven species. Subsequent study with increased sampling (Hoekstra, unpub.) has revealed that the African species of Friesodielsia van Steenis (1948: 458) and Exellia Boutique (1951b: 117) are nested in Monanthotaxis. Whatever the solution and taxonomic consequences, the name Monanthotaxis with the type Monanthotaxis congoensis Baillon (1890: 879) will be retained as it is the oldest valid generic name. Along with phylogenetic analysis, we are conducting a taxonomic revision. The last revision of Monanthotaxis and allied genera was published over a century ago by Engler & Diels (1901). Since then, only contributions to local floras have been published (e.g. Boutique 1951a, Le Thomas 1969, Robson 1960, Verdcourt 1971a). While studying the material of Monanthotaxis, we encountered a remarkable new species, which differs from all other species of Annonaceae in its large and lax panicle-like inflorescence. Panicle-like inflorescences are rare in Annonaceae, and those that have been recorded are either congested, as in e.g. Unonopsis and Guatteria (Erkens et al. 2008, Maas et al. 2007), or with only a few flowers, as in Monanthotaxis le-testui Pellegrin (1950: 75). This new species is probably closely related to M. congoensis since they share several characters. Verdcourt (1971b) divided the genus in three subgenera and five sections. In his classification, this new species would join M. congoensis in the typical section Monanthotaxis, which is easily distinguished by having flowers with the four to six petals in a single whorl and less than 17 stamens. Because it is so similar to M. congoensis, our new species will almost certainly be classified within Monanthotaxis, and we decided to publish it before a new generic classification has been completed

Some finite-graph models for process algebra

In this paper, we present a number of closely related models of process algebra, called finite-graph models. In a finite-graph model of process algebra, each process is a bisimulafion class of a particular kind of process graphs, called recursive process graphs. Just as in the standard graph model, each guarded each guarded recursive specification has exactly one solution in a finite-graph model, but in contrast to the standard graph model, this solution can be shown to contain a finite recursive process graph as element

Fiber diameter, porosity and functional group gradients in electrospun scaffolds

Developing, homeostatic, and regenerating tissues are full of various gradients, including mechanical, chemical, porosity and growth-factor gradients. However, it remains challenging to replicate these gradients using common tissue engineering approaches. Here, we use electrospinning to create scaffolds with in-depth gradients. We created a fiber diameter gradient and pore size gradient throughout the depth of electrospun (ESP) scaffolds by a continuous gradient of polymer concentration. As an alternative to this established method, we developed a novel method to create fiber diameter gradients by changing the voltage on both needle and collector, keeping the total voltage constant. In this way, fiber diameter could be changed in a gradient matter by focusing the electrospinning spot. Using this method, we created a fiber diameter and pore size gradient, while keeping all other parameters constant. Lastly, we developed a novel method to create functional group gradients, which can potentially be used in a wide variety of polymer solutions to couple peptides and proteins to ESP scaffolds. A scaffold with an in-depth gradient of functional groups was created by adding functionalized poly(ethylene glycol) additives to the polymer solution, a novel method with potentially wide applications. The techniques demonstrated here could be applied to a wide variety of polymers and applications and can aid in developing physiologically relevant gradient scaffolds.</p

Bioprinting:From Tissue and Organ Development to <i>in Vitro</i> Models

Bioprinting techniques have been flourishing in the field of biofabrication with pronounced and exponential developments in the past years. Novel biomaterial inks used for the formation of bioinks have been developed, allowing the manufacturing of in vitro models and implants tested preclinically with a certain degree of success. Furthermore, incredible advances in cell biology, namely, in pluripotent stem cells, have also contributed to the latest milestones where more relevant tissues or organ-like constructs with a certain degree of functionality can already be obtained. These incredible strides have been possible with a multitude of multidisciplinary teams around the world, working to make bioprinted tissues and organs more relevant and functional. Yet, there is still a long way to go until these biofabricated constructs will be able to reach the clinics. In this review, we summarize the main bioprinting activities linking them to tissue and organ development and physiology. Most bioprinting approaches focus on mimicking fully matured tissues. Future bioprinting strategies might pursue earlier developmental stages of tissues and organs. The continuous convergence of the experts in the fields of material sciences, cell biology, engineering, and many other disciplines will gradually allow us to overcome the barriers identified on the demanding path toward manufacturing and adoption of tissue and organ replacements.</p

The interobserver and test-retest variability of the dysphonia severity index

Objective: The purpose of this study was to investigate the interobserver variability and the test-retest variability of the Dysphonia Severity Index (DSI), a multiparametric instrument to assess voice quality. Methods: The DSI was measured in 30 nonsmoking volunteers without voice complaints or voice disorders by two speech pathologists. The subjects were measured on 3 different days, with an interval of 1 week. Results: The difference in DSI between two observers (interobserver difference) was not significant. The intraclass correlation coefficient for the DSI was 0.79. The standard deviation of the difference between two duplicate measurements by different observers was 1.27. Conclusion: Differences in measurements between different observers were not significant. The intraclass correlation coefficient of the DSI was 0.79, which is to be considered good. Differences in DSI within one patient need to be larger than 2.49 to be significant. Copyrigh

Multimaterial tandem electrospinning for spatially modulated neural guidance

The goal of this work is the creation of an in vitro platform to investigate the combined effects of patterned topographical and bioactive cues towards achieving the spatially controlled growth of peripheral sensory neurons