ABSTRACT
Soft grippers that incorporate functional materials are important in the development of mechanically compliant and multifunctional interfaces for both sensing and stimulating soft objects and organisms. In particular, the capability for firm and delicate grasping of soft cells and organs without mechanical damage is essential to identify the condition of and monitor meaningful biosignals from objects. Here, we report a millimeter-scale soft gripper based on a shape memory polymer that enables manipulating a heavy object (payload-to-weight ratio up to 6400) and grasping organisms at the micro/milliscale. The silver nanowires and crack-based strain sensor embedded in this soft gripper enable simultaneous measurement of the temperature and pressure on grasped objects and offer temperature and mechanical stimuli for the grasped object. We validate our miniaturized soft gripper by demonstrating that it can grasp a snail egg while simultaneously applying a moderate temperature stimulation to induce hatching process and monitor the heart rate of a newborn snail. The results present the potential for widespread utility of soft grippers in the area of biomedical engineering, especially in the development of conditional or closed-loop interfacing with microscale biotissues and organisms.
Subject(s)
Biomedical Engineering , Equipment Design , Hand Strength/physiology , Robotics , Smart Materials/chemistry , Snails/physiology , Animals , Bioengineering , Biomimetics , Biotechnology/methods , Calibration , Elastic Modulus , Humans , Man-Machine Systems , Materials Testing , Nanowires , Pressure , Stress, Mechanical , TemperatureABSTRACT
OBJECTIVE: The objective of this study was to assess the association between women with endometriosis and risk of preterm birth. METHODS: Two reviewers independently determined all prospective cohort study, retrospective cohort study, large population based cohort study, retrospective secondary analysis, and double blinded, multicentric, observational and cohort study, placebo-controlled, randomized clinical trial published using PubMed, Medline, Korea Education and Research Information Service, and Scopus from March 1994 through February 2016 without language restrictions comparing obstetric outcomes women with endometriosis and women without endometriosis. The meta-analysis was performed following the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement. Six studies met inclusion criteria, including 50,472 women. Among 50,472 pregnancies, 39,659 had endometriosis and 10,813 had no endometriosis. Meta-analyses were estimated with odds ratios and 95% confidence intervals using random effect analysis according to heterogeneity of studies. RESULTS: Data from six effect sizes from six studies involving 50,472 patients were enrolled. These meta-analyses showed women with endometriosis have an increased risk of preterm birth (odds ratio, 1.473; 95% confidence interval, 1.216 to 1.785). CONCLUSION: These meta-analyses demonstrate women with endometriosis at pregnancy have an increased risk of preterm birth. Therefore, it is worthy for obstetrics to increase the careful inspection in women with endometriosis during pregnancy.
