Active fixturing: literature review and future research directions

Fixtures are used to fixate, position and support workpieces and represent a crucial tool in manufacturing. Their performance determines the result of the whole manufacturing process of a product. There is a vast amount of research done on automatic fixture layout synthesis and optimisation and fixture design verification. Most of this work considers fixture mechanics to be static and the fixture elements to be passive. However, a new generation of fixtures has emerged that has actuated fixture elements for active control of the part–fixture system during manufacturing operations to increase the end product quality. This paper analyses the latest studies in the field of active fixture design and its relationship with flexible and reconfigurable fixturing systems. First, a brief introduction is given on the importance of research of fixturing systems. Secondly, the basics of workholding and fixture design are visited, after which the state-of-the-art in active fixturing and related concepts is presented. Fourthly, part–fixture dynamics and design strategies which take these into account are discussed. Fifthly, the control strategies used in active fixturing systems are examined. Finally, some final conclusions and prospective future research directions are presented

A randomized placebo-controlled clinical trial of a multi-strain probiotic formulation (Bio-Kult®) in the management of diarrheapredominant irritable bowel syndrome

Background: Accumulating evidence supports the view that an imbalance of gut bacteria contributes to IBS, and that increasing the mass of beneficial species may reduce the numbers of pathogenic bacteria and help alleviate symptoms.Methods: In this double-blind trial 400 adult patients with moderate-to-severe symptomatic diarrhea-predominant IBS (IBS-D) were randomized to treatment with the multi-strain probiotic Bio-Kult® (14 different bacterial strains) or placebo for 16 weeks. The change in severity and frequency of abdominal pain was the primary outcome measure.Results: Probiotic treatment significantly improved the severity of abdominal pain in patients with IBS-D. A 69% reduction for probiotic versus 47% for placebo (p < 0,001) equates to a 145 point reduction on the IBS-severity scoring system (IBS-SSS). The proportion of patients who rated their symptoms as moderate-to-severe was reduced from 100% at baseline to 14% for the multi-strain probiotic at follow-up (month 5) versus 48% for placebo (p < 0,001). Also, the number of bowel motions per day from month 2 onwards was significantly reduced in the probiotic group compared with the placebo group (p < 0,05). In addition to relieving symptoms, the probiotic markedly improved all dimensions of quality of life in the 34-item IBS-Quality of Life (IBS-QoL) questionnaire. No serious adverse events were reported.Conclusions: The multi-strain probiotic was associated with significant improvement in symptoms in patients with IBSD and was well-tolerated. These results suggest that probiotics confer a benefit in IBS-D patients which deserves further investigation. Trial registration: [Clinicaltrials.gov NCT03251625; retrospectively registered on August 9, 2017]