Making serine integrases work for us

DNA site-specific recombinases are enzymes (often associated with mobile DNA elements) that catalyse breaking and rejoining of DNA strands at specific points, thereby bringing about precise genetic rearrangements. Serine integrases are a group of recombinases derived from bacteriophages. Their unusual properties, including directionality of recombination and simple site requirements, are leading to their development as efficient, versatile tools for applications in experimental biology, biotechnology, synthetic biology and gene therapy. This article summarizes our current knowledge of serine integrase structure and mechanism, then outlines key factors that affect the performance of these phage recombination systems. Recently published studies, that have expanded the repertoire of available systems and reveal system-specific characteristics, will help us to choose the best integrases for envisaged applications

Three stage rocket vehicle with parallel staging

A three stage rocket vehicle has a large forward propellant tank and a small aft propellant tank axially aligned. Secured to the rear end of the aft propellant tank is an engine mount structure carrying rocket engines. Offset and secured to the propellant tanks is a payload structure. The propellants from the large forward tank are fed into the aft propellant tank. This arrangement enables the vehicle to parallel stage its use of engines and components and results in significant payload capability. The design and components fully utilize existing space shuttle elements and tooling

Why are Liberal Education\u27s Friends of so Little Help?

Emphasizes the need for college teachers to apply diligence in improving teaching methods towards the achievement of liberal education goals. Potential for teachers to advance knowledge and awareness on liberal education; Factors that can be attributed to the failure of colleges and universities in the U.S. to make progress in their liberal programs and aims; Ways to address liberal education issues

Aging and Work in Canada: Firm Policies

Few Canadian firms have explicit policies dealing with the aging of their workforces, other than pension policies geared to a conventional retirement age. However, other firm policies have unanticipated consequences that apply differentially to older and younger workers. This paper reviews several relevant firm practices used in Canada, including pension and benefits practices, training policies and programs, and work and family practices. The most dramatic firm practice that has an impact on the older worker is restructuring through downsizing the workforce by means of retirement incentives and layoffs. We introduce the issue by considering available national-level Canadian data, and then consider five case studies representing different configurations of firm practices. These cases are: Sun Life Assurance Company of Canada, NOVA Corporation, Slater Steels, Bell Canada, and the garment industry in Montreal. Both management and employee level data are presented. We argue the importance of organizational latitude in establishing firm-based policies that dramatically change the nature of the life course in Canada.aging workforce; firm policies

The Academy of Dental Materials: Providing roots and wings.

ObjectivesThe long history of the Academy of Dental Materials (ADM) is documented with its strategies (a) to rapidly communicate science among its members, (b) to establish special awards to stimulate new science, and (c) to develop new dental materials scientists.MethodsWe searched the history of the last 35 years of the ADM newsletters, transactions, journals, and officer notes. We document the (a) presidents, (b) meeting history, (c) membership growth, and (d) development of special awards through 2019 with the recent creation of the ADM Marshall Post-Doctoral Award.ResultsThere are 36 years of recent ADM history, 42 international meetings, membership growth to 400 individuals from 15 countries, service of 19 presidents, Paffenbarger annual Awardees since 1989, induction of >200 fellows, and recognition of the first winner of Marshall Post-Doctoral Award in 2018. New directions for recruiting members are suggested. Three potential new thrusts for the organization are presented: artificial intelligence, genetic engineering, and intensive member mentoring.SignificanceThese suggestions for the ADM provide a path for the ADM to continue to adapt to the ever changing scientific landscape