Gas separation membrane

A method of fabricating a gas separation membrane includes providing a coextruded multilayer film that includes a first polymer layer formed of a first polymer material and a second polymer layer formed of a second polymer material, the first polymer material having a first gas permeability. The coextruded multilayer film is axially oriented such that the second polymer layer has a second gas permeability that is greater than the first gas permeability.Board of Regents, University of Texas Syste

Leadership between decks: a synthesis and development of engagement and resistance theories of leadership based on evidence from practice in Royal Navy warships

Purpose To understand the role of interaction in the process of leadership. Interaction has been claimed to be a leadership competence in earlier research into leadership in the Royal Navy. The aim of this research is to define how interaction works within naval teams. Design/methodology/approach The research uses Grounded Theory. Following a series of leadership discussions in separate focus groups, discussion topics were coded and subjected to recursive qualitative analysis. The grounded approach is used to synthesise and develop existing leadership theory strands as well as to extend the trait-process approach to leadership. Findings The research discovers the key interaction behaviours of engagement, disengagement and levelling. Our findings support recent developments in follower-centric perceptions of leadership and in interaction specifically. We develop engagement theory by combining it with the less well researched area of leadership resistance. We then re-frame resistance as social levelling, a more comprehensive interaction mechanism. Research limitations/implications The research is highly contextual because of its qualitative approach. Some of the detailed reactions to leadership behaviours may not found in other naval or military teams and are unlikely to be generalizable to non-military environments. However, the mechanism described, that of engagement, disengagement and levelling is considered highly generalizable if not universal. Rather than develop new theory fragments in an already confusing research environment, we fuse engagement and resistance theory to extend trait-process theories of leadership. The result is a coherent and integrative model of leadership dynamics which frames leadership in the mundane interaction of leaders and followers. Practical implications Interaction as a competence is strongly supported as is the encouragement of cultures which promote interaction. Selection procedures for future leaders should include interaction skills. The use of subtle methods of resistance are highlighted. Such methods may indicate poor interaction long before more overt forms of resistance are apparent. Originality/value This research uniquely uses Grounded Theory to extend current theories (competence based leadership and trait-process theories of leadership), explaining the complexity of leadership-interaction. The research also synthesises and develops engagement and levelling (resistance to leadership) theories for the first time. As such the project suggests a full range model of follower response to leadership including subtle forms of resistance to power. The value of group-level analysis using focus groups is recommended, especially for other collective leader-follower approaches to leadership. The research is of interest to those studying leadership process theories, competencies, leader-follower traditions, engagement and power/resistance research

Parasitoid complex of fall armyworm, spodoptera frugiperda, in Ghana and Benin

Open Access Journal; Published online: 21 Jan 2020The fall armyworm, Spodoptera frugiperda, a moth originating from the American continent, has recently invaded most African countries, where it is seriously threatening food security as a pest of cereals. The current management methods rely heavily on the use of synthetic insecticides but there is a need for more sustainable control methods, including biological control. Surveys were conducted in two West African countries, Ghana and Benin, to determine the native parasitoid complex and assess parasitism rates of S. frugiperda. Samples of S. frugiperda eggs and larvae were collected in maize fields located in 56 and 90 localities of Ghana and Benin, respectively, from July 2018 to July 2019. Ten species were found parasitizing the pest, including two egg parasitoids, one egg–larval, five larval and two larval–pupal parasitoids. The two most abundant parasitoids in both countries were two Braconidae: the egg‐larval parasitoid Chelonus bifoveolatus and the larval parasitoid Coccygidum luteum. Parasitism rates were determined in three Ghanaian regions and averages varied from 0% to 75% between sites and from 5% to 38% between regions. These data provide an important baseline for the development of various biological control options. The two egg parasitoids, Telenomus remus and Trichogramma sp. can be used in augmentative biological control and investigations should be conducted to assess how cultural practices can enhance the action of the main parasitoids, C. luteum and Ch. bifoveolatus, in the field. Understanding the parasitoid complex of S. frugiperda in Africa is also necessary before any development of classical biological controls involving the introduction of parasitoids from the Americas