Biodegradable electrohydraulic actuators for sustainable soft robots.

Combating environmental pollution demands a focus on sustainability, in particular from rapidly advancing technologies that are poised to be ubiquitous in modern societies. Among these, soft robotics promises to replace conventional rigid machines for applications requiring adaptability and dexterity. For key components of soft robots, such as soft actuators, it is thus important to explore sustainable options like bioderived and biodegradable materials. We introduce systematically determined compatible materials systems for the creation of fully biodegradable, high-performance electrohydraulic soft actuators, based on various biodegradable polymer films, ester-based liquid dielectric, and NaCl-infused gelatin hydrogel. We demonstrate that these biodegradable actuators reliably operate up to high electric fields of 200 V/µm, show performance comparable to nonbiodegradable counterparts, and survive more than 100,000 actuation cycles. Furthermore, we build a robotic gripper based on biodegradable soft actuators that is readily compatible with commercial robot arms, encouraging wider use of biodegradable materials systems in soft robotics.

Transgender health and medicine - Are radiological devices prepared?

BACKGROUND & AIMS: To determine if radiological hard- and software offers options beyond the binary female / male classification. METHODS: We surveyed thirteen radiological hardware and six radiological software vendors about the options to enter patient gender. RESULTS: Six of thirteen hardware and five of six software vendors replied to our inquiry. All vendors except one offered a third option in addition to male / female. CONCLUSION: We found that most hard- and software systems provide with a third option for patient gender. These systems allow radiology personnel to accurately document patient gender in the medical record and contribute to an inclusive patient experience in the radiology department. Registering the biological sex in addition to gender may further improve medical care.

Associations of Gait Disorders and Recurrent Falls in Older People: A Prospective Population-Based Study.

BACKGROUND: Recurrent falls represent a major source of serious adverse health outcomes in the general older population. Gait impairment has been linked to recurrent falls, but there are only limited long-term data on this association. OBJECTIVES: The objective of the study was to investigate the association of gait disorders (GDs) and gait tests with future falls in an existing longitudinal population-based cohort. METHOD: The study was performed in participants of the Bruneck Study cohort 2010 aged 60-97 years, with prospective 5-year follow-up. At baseline, participants underwent a clinical gait assessment (to determine neurological and non-neurological GDs according to an established classification) and were also evaluated by quantitative and semiquantitative gait tests (Hauser Index, Tinetti balance and gait test, and gait speed). Logistic regression analysis adjusted for age and sex was used to determine the relationship of baseline variables with incident recurrent falls at 5-year follow-up. RESULTS: Of 328 included participants, 22 (6.7%) reported recurrent falls at follow-up. Baseline presence of GDs was associated with recurrent falls at follow-up (odds ratio [OR] 4.2; 95% confidence interval [CI] 1.6-11.1; p = 0.004), and this effect was largely driven by neurological GDs (OR 5.5; 95% CI 1.7-17.4; p = 0.004). All 3 simple gait tests were predictive for incident falls (Hauser Index, p = 0.002; Tinetti test, p = 0.006; and gait speed, p < 0.001). CONCLUSIONS: Clinical assessment of GDs and gait tests both had independent significant predictive value for recurrent falls over a 5-year follow-up period. This highlights the potential of such assessments for early fall risk screening and timely implementation of fall-preventive measures.

Can carbon labels encourage green food choices?

Introduction: A conventionally grown kiwi from Spain or an organic pineapple from Ghana? Which is the more environmentally friendly option? Given that the production and distribution of food is responsible for about a quarter of our CO2e emissions and thus plays a role in climate change the answer to such questions and, accordingly, making the right food product choices is crucial. The problem, however, is that it is difficult for consumers to calculate the CO2e value of food as it depends on several specifications such as the type of food, origin, etc. Could carbon labeling of food circumvent this problem and help consumers make more environmentally friendly choices? Methods: In an online experiment, 402 participants had to choose 20 food products from a fictitious online shop. The participants were randomly assigned to either one of three food labeling conditions (Star Rating, Green Foot, and Traffic Light Label, short TLL) or the control condition. Results: The labeling conditions resulted in lower overall CO2e emissions, the purchase of more green food products and fewer red food products than in the control condition. The TLL outperformed the other two labels and was also the most accepted. Discussion: The carbon TLL is therefore a promising intervention to help consumers to not only choose more environmentally friendly foods, but also make a significant contribution to the fight against climate change.

Becoming Sustainable, The New Frontier in Soft Robotics.

The advancement of technology has a profound and far-reaching impact on the society, now penetrating all areas of life. From cradle to grave, one is supported by and depends on a wide range of electronic and robotic appliances, with an ever more intimate integration of the digital and biological spheres. These advances, however, often come at the price of negatively impacting our ecosystem, with growing demands on energy, contributions to greenhouse gas emissions and environmental pollution-from production to improper disposal. Mitigating these adverse effects is among the grand challenges of the society and at the forefront of materials research. The currently emerging forms of soft, biologically inspired electronics and robotics have the unique potential of becoming not only like their natural antitypes in performance and capabilities, but also in terms of their ecological footprint. This review outlines the rise of sustainable materials in soft and bioinspired robotics, targeting all robotic components from actuators to energy storage and electronics. The state-of-the-art in biobased robotics spans flourishing fields and applications ranging from microbots operating in vivo to biohybrid machines and fully biodegradable yet resilient actuators. These first steps initiate the evolution of robotics and guide them into a sustainable future.

Resilient yet entirely degradable gelatin-based biogels for soft robots and electronics.

Biodegradable and biocompatible elastic materials for soft robotics, tissue engineering or stretchable electronics with good mechanical properties, tunability, modifiability or healing properties drive technological advance, and yet they are not durable under ambient conditions and do not combine all the attributes in a single platform. We have developed a versatile gelatin-based biogel, which is highly resilient with outstanding elastic characteristics, yet degrades fully when disposed. It self-adheres, is rapidly healable and derived entirely from natural and food-safe constituents. We merge all the favourable attributes in one material that is easy to reproduce and scalable, and has a low-cost production under ambient conditions. This biogel is a step towards durable, life-like soft robotic and electronic systems that are sustainable and closely mimic their natural antetypes.

A Lesson from Plants: High-Speed Soft Robotic Actuators.

Rapid energy-efficient movements are one of nature's greatest developments. Mechanisms like snap-buckling allow plants like the Venus flytrap to close the terminal lobes of their leaves at barely perceptible speed. Here, a soft balloon actuator is presented, which is inspired by such mechanical instabilities and creates safe, giant, and fast deformations. The basic design comprises two inflated elastomer membranes pneumatically coupled by a pressurized chamber of suitable volume. The high-speed actuation of a rubber balloon in a state close to the verge of mechanical instability is remotely triggered by a voltage-controlled dielectric elastomer membrane. This method spatially separates electrically active and passive parts, and thereby averts electrical breakdown resulting from the drastic thinning of an electroactive membrane during large expansion. Bistable operation with small and large volumes of the rubber balloon is demonstrated, achieving large volume changes of 1398% and a high-speed area change rate of 2600 cm2 s-1. The presented combination of fast response time with large deformation and safe handling are central aspects for a new generation of soft bio-inspired robots and can help pave the way for applications ranging from haptic displays to soft grippers and high-speed sorting machines.

Vacuum-processed polyethylene as a dielectric for low operating voltage organic field effect transistors.

We report on the fabrication and performance of vacuum-processed organic field effect transistors utilizing evaporated low-density polyethylene (LD-PE) as a dielectric layer. With C60 as the organic semiconductor, we demonstrate low operating voltage transistors with field effect mobilities in excess of 4 cm2/Vs. Devices with pentacene showed a mobility of 0.16 cm2/Vs. Devices using tyrian Purple as semiconductor show low-voltage ambipolar operation with equal electron and hole mobilities of ∼0.3 cm2/Vs. These devices demonstrate low hysteresis and operational stability over at least several months. Grazing-angle infrared spectroscopy of evaporated thin films shows that the structure of the polyethylene is similar to solution-cast films. We report also on the morphological and dielectric properties of these films. Our experiments demonstrate that polyethylene is a stable dielectric supporting both hole and electron channels.

Limitations of the MELD score in predicting mortality or need for removal from waiting list in patients awaiting liver transplantation.

BACKGROUND: Decompensated cirrhosis is associated with a poor prognosis and liver transplantation provides the only curative treatment option with excellent long-term results. The relative shortage of organ donors renders the allocation algorithms of organs essential. The optimal strategy based on scoring systems and/or waiting time is still under debate. METHODS: Data sets of 268 consecutive patients listed for single-organ liver transplantation for nonfulminant liver disease between 2003 and 2005 were included into the study. The Model for End-Stage Liver Disease (MELD) and Child-Turcotte-Pugh (CTP) scores of all patients at the time of listing were used for calculation. The predictive ability not only for mortality on the waiting list but also for the need for withdrawal from the waiting list was calculated for both scores. The Mann-Whitney-U Test was used for the univariate analysis and the AUC-Model for discrimination of the scores. RESULTS: In the univariate analysis comparing patients who are still on the waiting list and patients who died or were removed from the waiting list due to poor conditions, the serum albumin, bilirubin INR, and CTP and MELD scores as well as the presence of ascites and encephalopathy were significantly different between the groups (p < 0.05), whereas serum creatinine and urea showed no difference. Comparing the predictive abilities of CTP and MELD scores, the best discrimination between patients still alive on the waiting list and patients who died on or were removed from the waiting list was achieved at a CTP score of >or=9 and a MELD score of >or=14.4. The sensitivity and specificity to identify mortality or severe deterioration for CTP was 69.0% and 70.5%, respectively; for MELD, it was 62.1% and 72.7%, respectively. This result was supported by the AUC analysis showing a strong trend for superiority of CTP over MELD scores (AUROC 0.73 and 0.68, resp.; p = 0.091). CONCLUSION: The long term prediction of mortality or removal from waiting list in patients awaiting liver transplantation might be better assessed by the CTP score than the MELD score. This might have implications for the development of new improved scoring systems.

Enhancement of arsenic trioxide-mediated apoptosis using docosahexaenoic acid in arsenic trioxide-resistant solid tumor cells.

It has been shown that the polyunsaturated fatty acid docosahexaenoic acid (DHA) can sensitize various tumor cells to reactive oxygen species (ROS)-inducing anticancer agents. Recently, we demonstrated that DHA also enhances the apoptotic effect of clinically achievable concentrations (1-2 microM) of arsenic trioxide (As2O3) in several As2O3-resistant human leukemic cell lines via a ROS-dependent mechanism. The aim of the present study was to evaluate whether this combined effect of As2O3 and DHA is also applicable to As2O3-resistant solid tumor cells. We have tested 12 different tumor cell lines, including MDA-MB-468, SK-BR-3, MCF-7 (breast cancer), ES-2, SKOV-3 (ovarian cancer), HT-29, SW-620, LS-174T (colon cancer), PC-3 (prostate cancer), HeLa (cervical cancer), PANC-1 (pancreatic cancer) and one primary melanoma cell line. With the exception of MDA-MB-468 and ES-2, all cells were resistant to treatment with either As2O3 or DHA alone. However, combined treatment with As2O3 and DHA significantly reduced viability in 7 of the 10 As2O3-resistant solid tumors tested. The cytotoxic effect of As2O3 and DHA was associated with the induction of apoptosis and a concomitant increase of intracellular lipid peroxidation products. Importantly, the combined effect of As2O3 and DHA was selectively toxic for malignant cells since no cytotoxic effect was observed in normal skin fibroblasts, human microvascular endothelial cells and peripheral blood mononuclear cells derived from healthy donors. Our data indicate that DHA may help to extend the therapeutic spectrum of As2O3 in the treatment of solid tumors since it may overcome de novo or acquired resistance to As2O3.

Docosahexaenoic acid enhances arsenic trioxide-mediated apoptosis in arsenic trioxide-resistant HL-60 cells.

Recent reports indicate a broad spectrum of antileukemic activity for arsenic trioxide (As(2)O(3)) due to its ability to induce apoptosis via intracellular production of reactive oxygen species (ROS). Despite its potent apoptotic mechanism, As(2)O(3) is not equally effective in all leukemic cells, which has prompted a search for agents enhancing As(2)O(3) efficacy. Recently, evidence has been gathered that the polyunsaturated fatty acid docosahexaenoic acid (DHA) may sensitize tumor cells to ROS-inducing anticancer agents. The aim of our investigation was to evaluate whether DHA enhances As(2)O(3)-mediated apoptosis in As(2)O(3)-resistant HL-60 cells. While 1 microM As(2)O(3) or 25 microM DHA reduced cell viability to 85.8% +/- 2.9% and 69.2% +/- 3.6%, combined treatment with As(2)O(3) and DHA reduced viability to 13.0% +/- 9.9% with a concomitant increase of apoptosis. Apoptotic cell death was preceded by collapse of the mitochondrial membrane potential, increased expression of proapoptotic B-cell lymphoma protein-2-associated X protein (Bax), and caspase-3 activation. Importantly, the combined effect of As(2)O(3) and DHA was associated with increased production of intracellular ROS and toxic lipid peroxidation products and was abolished by the antioxidant vitamin E or when oleic acid (a nonperoxidizable fatty acid) was used in place of DHA. Intracellular ROS and toxic lipid peroxidation products most likely constitute the key mediators contributing to the combined effect of As(2)O(3) and DHA. Our data provide the first evidence that DHA may help to extend the therapeutic spectrum of As(2)O(3) and suggest that the combination of As(2)O(3) and DHA could be more broadly applied in leukemia therapy.