Natural deduction and coherence for weakly distributive categories

AbstractThis paper examines coherence for certain monoidal categories using techniques coming from the proof theory of linear logic, in particular making heavy use of the graphical techniques of proof nets. We define a two sided notion of proof net, suitable for categories like weakly distributive categories which have the two-tensor structure (times/par) of linear logic, but lack a negation operator. Representing morphisms in weakly distributive categories as such nets, we derive a coherence theorem for such categories. As part of this process, we develop a theory of expansion-reduction systems with equalities and a term calculus for proof nets, each of which is of independent interest. In the symmetric case the expansion-reduction system on the term calculus yields a decision procedure for the equality of maps for free weakly distributive categories.The main results of this paper are these. First we have proved coherence for the full theory of weakly distributive categories, extending similar results for monoidal categories to include the treatment of the tensor units. Second, we extend these coherence results to the full theory of ∗-autonomous categories — providing a decision procedure for the maps of free symmetric ∗-autonomous categories. Third, we derive a conservative extension result for the passage from weakly distributive categories to ∗-autonomous categories. We show strong categorical conservativity, in the sense that the unit of the adjunction between weakly distributive and ∗-autonomous categories is fully faithful

A Historiometric Examination of Machiavellianism and a New Taxonomy of Leadership

Although researchers have extensively examined the relationship between charismatic leadership and Machiavellianism (Deluga, 2001; Gardner & Avolio, 1995; House & Howell, 1992), there has been a lack of investigation of Machiavellianism in relation to alternative forms of outstanding leadership. Thus, the purpose of this investigation was to examine the relationship between Machiavellianism and a new taxonomy of outstanding leadership comprised of charismatic, ideological, and pragmatic leaders. Using an historiometric approach, raters assessed Machiavellianism via the communications of 120 outstanding leaders in organizations across the domains of business, political, military, and religious institutions. Academic biographies were used to assess twelve general performance measures as well as twelve general controls and five communication specific controls. The results indicated that differing levels of Machiavellianism is evidenced across the differing leader types as well as differing leader orientation. Additionally, Machiavellianism appears negatively related to performance, though less so when type and orientation are taken into account.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Aspergillus nidulans Septin AspB Plays Pre- and Postmitotic Roles in Septum, Branch, and Conidiophore Development

Members of the septin family of proteins act as organizational scaffolds in areas of cell division and new growth in a variety of organisms. Herein, we show that in the filamentous fungus Aspergillus nidulans, the septin AspB is important for cellular division, branching, and conidiation both pre- and postmitotically. AspB localizes postmitotically to the septation site with an underlying polarity that is evident as cytokinesis progresses. This localization at the septation site is dependent on actin and occurs before the cross-wall is visible. AspB localizes premitotically as a ring at sites of branching and secondary germ tube emergence. It is the only known branch site marker. In addition, AspB is found at several stages during the development of the asexual reproductive structure, the conidiophore. It localizes transiently to the vesicle/metula and metula/phialide interfaces, and persistently to the phialide/conidiospore interface. A temperature-sensitive mutant of AspB shows phenotypic abnormalities, including irregular septa, high numbers of branches, and immature asexual reproductive structures

Alluvial Sedimentation and Erosion in an Urbanizing Watershed,Gwynn Falls, Maryland

Earlier measurements of stream channel geometry on 19 reaches were repeated to provide a longitudinal study of stream channel adjustment over 13 years (1987-2000) in the urbanizing Gwynns Falls, Maryland watershed. We observed both enlargement and reduction in channel size, depending on the extent of upstream development, the timing and location of urbanization and upstream channel adjustment, and the presence of hydrologic constrictions and grade controls. Based on a relatively simple visual assessment of the composition, size, and extent of instream sediment storage, we categorized stream reaches into three phases: aggraded (7 sites), early erosion (7 sites), and late erosion (5 sites). Aggraded sites had point and lateral bars mantled with fine-grained sediment and experienced some reduction in cross-sectional area, primarily through the deposition of fine-grained material on bars in the channel margins. Early erosion sites had smaller bars and increases in channel cross-sectional area as a consequence of the evacuation of in-channel fine-grained sediment. Fine-grained sediments were either entirely absent or found only at a few high bar elevations at late erosion sites. Sediment evacuation from late erosion sites has both enlarged and simplified channels, as demonstrated by an increase in cross-sectional area and a strong decrease in channel width variation. Channel cross-sectional area enlargement, reduced channel width variation, and channel incision were ubiquitous at erosion sites. As a result, overbank flows were less common in the erosion sites as determined by high water marks left by a 2-year flood that occurred during the study period. Principal causes for channel changes appear to be increased high flow durations and reduced sediment supply. Spatial variation in channel conditions could not be tied simply to sub-basin impervious cover or watershed area. In-channel sediment storage is a useful indicator of channel form and adjustment. When combined with information on development and sedimentation conditions in the contributing drainage, instream sediment storage can be used to effectively assess future channel adjustments