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1.
Rev Assoc Med Bras (1992) ; 70(6): e20231614, 2024.
Article in English | MEDLINE | ID: mdl-39045956

ABSTRACT

OBJECTIVE: Melatonin plays a role in many biological and physiological events. There are studies in the literature relating melatonin levels to many psychiatric disorders such as schizophrenia, bipolar disorder, and major depressive disorder. We aimed to investigate the relationship between serum melatonin levels with the Beck Depression Inventory and the Beck Scale for Suicidal Ideation in suicide patients. METHODS: The study was conducted prospectively with volunteer patients aged 20-50 years who were admitted to the emergency department after a suicide attempt. The social and occupational status, educational levels, marital status, and stressor factors of patients were questioned. Beck Depression Inventory and Beck Scale for Suicidal Ideation were applied to each patient included in the study. Blood melatonin levels were evaluated using the enzyme-linked immunosorbent assay method. The data were analyzed with the SPSS 23.00 statistical program. Descriptive values were expressed by the number of cases (n), percentage (%), median (interquartile range), and mean±standard deviation. The Kolmogorov-Smirnov test was used to assess the distribution of continuous variables, and the Pearson or Spearman correlation test was used to assess the relationship between disease severity and melatonin level. A value of p<0.05 was considered statistically significant. RESULTS: No statistically significant correlation was found between melatonin level and the Beck Depression Inventory score (r=-0.098, p=0.44). However, a statistically weak, inverse, and significant correlation was discovered between melatonin levels and the Beck Scale for Suicidal Ideation score (r=-0.465, p=0.00). CONCLUSION: According to our results, it was determined that there was a significant negative relationship between melatonin level and the Beck Scale for Suicidal Ideation scoring.


Subject(s)
Melatonin , Psychiatric Status Rating Scales , Suicidal Ideation , Suicide, Attempted , Humans , Melatonin/blood , Adult , Female , Male , Middle Aged , Prospective Studies , Young Adult , Suicide, Attempted/psychology , Enzyme-Linked Immunosorbent Assay , Socioeconomic Factors , Severity of Illness Index , Depression/blood , Depression/psychology , Statistics, Nonparametric
2.
Front Robot AI ; 10: 1198749, 2023.
Article in English | MEDLINE | ID: mdl-37692530

ABSTRACT

A distinctive feature of quadrupeds that is integral to their locomotion is the tail. Tails serve many purposes in biological systems, including propulsion, counterbalance, and stabilization while walking, running, climbing, or jumping. Similarly, tails in legged robots may augment the stability and maneuverability of legged robots by providing an additional point of contact with the ground. However, in the field of terrestrial bio-inspired legged robotics, the tail is often ignored because of the difficulties in design and control. In this study, we test the hypothesis that a variable stiffness robotic tail can improve the performance of a sprawling quadruped robot by enhancing its stability and maneuverability in various environments. In order to validate our hypothesis, we integrated a cable-driven, flexible tail with multiple segments into the underactuated sprawling quadruped robot, where a single servo motor working alongside a reel and cable mechanism regulates the tail's stiffness. Our results demonstrated that by controlling the stiffness of the tail, the stability of locomotion on rough terrain and the climbing ability of the robot are improved compared to the movement with a rigid tail and no tail. Our findings highlight that constant ground support provided by the flexible tail is key to maintaining stable locomotion. This ensured a predictable gait cycle, eliminating unexpected turning and slipping, resulting in an increase in locomotion speed and efficiency. Additionally, we observed the robot's enhanced climbing ability on surfaces inclined up to 20°. The flexibility of the tail enabled the robot to overcome obstacles without external sensing, exhibiting significant adaptability across various terrains.

3.
Toxicol Res (Camb) ; 12(3): 400-407, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37397919

ABSTRACT

Research on heat-induced food contamination is being given more attention as a result of the health risks that have been publicly revealed in recent years. Furan is known as a colorless, combustible, heterocyclic aromatic organic molecule and is formed when food products are processed and stored. It has been established that furan, which is inevitably ingested, has a deleterious impact on human health and causes toxicity. Furan is known to have adverse effects on the immune system, neurological system, skin, liver, kidney, and fat tissue. Infertility caused by furan is a result of its damaging effects on several tissues and organs as well as the reproductive system. Although studies on the adverse effects of furan on the male reproductive system have been performed, there is no study revealing apoptosis in Leydig cells at the gene level. In this study, TM3 mouse Leydig cells were exposed to 250- and 2,500-µM concentrations of furan for 24 h. The findings demonstrated that furan decreased cell viability and antioxidant enzyme activity while increasing lipid peroxidation, reactive oxygen species, and apoptotic cell rates. Furan also increased the expression of the important apoptotic genes Casp3 and Trp53 while decreasing the expression of another pro-apoptotic gene, Bcl2, and antioxidant genes Sod1, Gpx1, and Cat. In conclusion, these results imply that furan may cause loss of cell function in mouse Leydig cells responsible for testosterone biosynthesis by impairing the efficiency of the antioxidant system, possibly by inducing cytotoxicity, oxidative stress, and apoptosis.

4.
Neurotox Res ; 41(6): 660-669, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37452911

ABSTRACT

In this study, we aimed to investigate the effects of carvacrol (CA), a widely used phytochemical having anti-oxidant and neuroprotective effects, on transient receptor potential (TRP) channels in an animal model of Parkinson's disease (PD). A total of 64 adult male Spraque-Dawley rats were divided into four groups: sham-operated, PD animal model (unilateral intrastriatal injections of 6-hydroxydopamine (6-OHDA), 6 µg/µl), PD + vehicle (dimethyl sulfoxide (DMSO)) treatment, and PD + CA treatment (10 mg/kg, every other day, for 14 days). Half of the brain samples of substantia nigra pars compacta (SNpc) and striatum (CPu) were collected for immunohistochemistry and the remaining half were used for molecular analyses. CA treatment significantly increased the density of dopaminergic neurons immunolabeled with tyrosine hydroxylase and transient receptor potential canonical 1 (TRPC1) channel in the SNpc of PD animals. In contrast, the density of astrocytes immunolabeled with glial fibrillary acetic acid and transient receptor potential ankyrin 1 (TRPA1) channel significantly decreased following CA treatment in the CPu of PD animals. RT-PCR and western blot analyses showed that 6-OHDA administration significantly reduced TRPA1 and TPRPC1 mRNA expression and protein levels in both SNpc and CPu. CA treatment significantly upregulated TRPA1 expression in PD group, while TRPC1 levels did not display an alteration. Based on this data it was concluded that CA treatment might protect the number of dopaminergic neurons by reducing the reactive astrogliosis and modulating the expression of TRP channels in both neurons and astrocytes in an animal model of PD.


Subject(s)
Parkinson Disease , Rats , Male , Animals , Parkinson Disease/drug therapy , Parkinson Disease/metabolism , Oxidopamine/toxicity , Oxidopamine/metabolism , Disease Models, Animal , Dopaminergic Neurons , Substantia Nigra/metabolism
5.
Toxicol Mech Methods ; 33(9): 796-805, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37488932

ABSTRACT

Furan is an organic chemical that can cause adverse effects on human health and is formed as a result of the thermal decomposition of many food components during cooking, storage, and processing techniques. Studies have shown that exposure to furan causes nephrotoxicity, hepatotoxicity, immunotoxicity, and reproductive toxicity. According to our current knowledge of the literature, the genotoxic mode of action of furan is highly controversial. The genotoxic effects of furan on the male reproductive system, however, have not been studied. In this study, the TM3 Leydig cell line was treated with 750, 1500, and 3000 µM concentrations of furan for 24 h. Following the completion of the exposure period, the cytotoxicity of furan in TM3 Leydig cells was assessed using a cell viability assay and a spectrophotometric measurement of lactate dehydrogenase (LDH) enzyme levels. The double fluorescence staining method was used to demonstrate furan-induced apoptosis, and DNA damage was shown using the micronucleus, comet, and chromosomal aberration assays. The result indicated that furan administration of Leydig cells resulted in an increase in structural chromosomal aberration, comet, and micronucleus formation, reduced cell viability, increased LDH activity, and a higher incidence of apoptotic cells. These findings revealed that furan induces DNA damage in TM3 Leydig cells, causing genotoxicity and DNA damage-induced cytotoxicity.


Subject(s)
DNA Damage , Leydig Cells , Male , Humans , Apoptosis , Chromosome Aberrations/chemically induced , Furans/toxicity , Comet Assay , Cell Survival
6.
Environ Sci Pollut Res Int ; 30(18): 53295-53308, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36853541

ABSTRACT

Worldwide research is being conducted to determine the level of acrylamide (ACR) that humans are exposed to from food and environmental sources. Glycidamide (GA) is an important epoxide metabolite of ACR, and its cytotoxicity is stronger than ACR. In this study, it was aimed to elucidate the effects and underlying mechanisms of GA on the induction of apoptosis in embryonic fibroblast cells. The toxicogenomic profile of GA was studied in terms of both apoptotic and oxidative stress. Embryonic fibroblast cells were exposed to GA (1 and 1000 µM) in the presence and absence of hesperidin (Hes) (20 µM) or vitamin C (VitC) (50 µM) for 24 h. Cell viability, cytotoxicity, lipid peroxidation, hydroxyl radicals, hydrogen peroxide, antioxidant enzyme levels and gene expressions, apoptotic, and oxidative stress-related gene expressions were measured in embryonic fibroblast cells. The results showed that GA induced cytotoxicity and diminished the expression levels of apoptotic genes. Furthermore, GA increased the levels of oxidative stress markers and significantly changed the oxidative stress-related gene expression. It has been determined that antioxidant molecules are considerably suppressed in GA-induced toxicity at both gene and enzyme levels. In addition to these results, when VitC, which is known to have strong antioxidant properties in eliminating the toxic effects of GA, is taken as reference, it has been proven that Hes has stronger antioxidant properties compared to VitC. Finally, GA-induced apoptosis in embryonic fibroblast cells is associated with nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent oxidative stress and Hes has antioxidant properties with strong effects.


Subject(s)
Antioxidants , Hesperidin , Humans , Antioxidants/pharmacology , Antioxidants/metabolism , Hesperidin/pharmacology , Oxidative Stress , Epoxy Compounds/toxicity , Fibroblasts/metabolism , Apoptosis , NF-E2-Related Factor 2/metabolism
7.
Theriogenology ; 193: 146-156, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36182826

ABSTRACT

Arsenite (As) and fluoride (F), both of which are linked to a variety of human ailments, are regularly found in underground drinking water. Numerous studies have shown that As and/or F have negative impacts on testicular function and fertility. For this purpose, mouse Leydig cells, the main cells responsible for the generation and regulation of steroid hormones such as testosterone, were used to reveal the effects of individual and combined exposure of As and F on the steroidogenic pathway in the male reproductive system. Leydig cells were treated with 0.39 µM (50 ppb) As and 0.0476 mM (2 ppm) F alone and in combination for 24 h. The findings revealed that As and/or F exposure induced oxidative stress and apoptosis in Leydig cells and altered antioxidant equilibrium of the cells by reducing superoxide dismutase, catalase, glutathione peroxidase. Additionally, individual and combined administration of As and/or F significantly supressed the expression of both steroidogenic enzymes and the genes encoding these enzymes. In conclusion, this study showed that exposure to As and F at environmentally relevant concentrations dispersed by water decreased testosterone production in Leydig cells, an important cell of the male reproductive system. The deleterious effects of even the lowest concentrations of As and F elements that can reach humans from the environment on the Leydig cell, and therefore on male infertility, emphasize necessity new safe limits for these elements.


Subject(s)
Arsenites , Drinking Water , Animals , Antioxidants/pharmacology , Arsenites/metabolism , Arsenites/toxicity , Catalase/metabolism , Drinking Water/metabolism , Fluorides/metabolism , Fluorides/pharmacology , Glutathione Peroxidase/genetics , Glutathione Peroxidase/metabolism , Humans , Leydig Cells/metabolism , Lipid Peroxidation , Male , Mice , Sodium Compounds , Sodium Fluoride/pharmacology , Steroids/metabolism , Superoxide Dismutase/metabolism , Testosterone/metabolism
8.
Proc Natl Acad Sci U S A ; 119(30): e2113912119, 2022 07 26.
Article in English | MEDLINE | ID: mdl-35857871

ABSTRACT

Studies of active matter-systems consisting of individuals or ensembles of internally driven and damped locomotors-are of interest to physicists studying nonequilibrium dynamics, biologists interested in individuals and swarm locomotion, and engineers designing robot controllers. While principles governing active systems on hard ground or within fluids are well studied, another class of systems exists at deformable interfaces. Such environments can display mixes of fluid-like and elastic features, leading to locomotor dynamics that are strongly influenced by the geometry of the surface, which, in itself, can be a dynamical entity. To gain insight into principles by which locomotors are influenced via a deformation field alone (and can influence other locomotors), we study robot locomotion on an elastic membrane, which we propose as a model of active systems on highly deformable interfaces. As our active agent, we use a differential driven wheeled robotic vehicle which drives straight on flat homogeneous surfaces, but reorients in response to environmental curvature. We monitor the curvature field-mediated dynamics of a single vehicle interacting with a fixed deformation as well as multiple vehicles interacting with each other via local deformations. Single vehicles display precessing orbits in centrally deformed environments, while multiple vehicles influence each other by local deformation fields. The active nature of the system facilitates a differential geometry-inspired mathematical mapping from the vehicle dynamics to those of test particles in a fictitious "spacetime," allowing further understanding of the dynamics and how to control agent interactions to facilitate or avoid multivehicle membrane-induced cohesion.


Subject(s)
Locomotion , Robotics , Humans
9.
Proc Natl Acad Sci U S A ; 119(31): e2200924119, 2022 Aug 02.
Article in English | MEDLINE | ID: mdl-35901212

ABSTRACT

Locomotion by shape changes or gas expulsion is assumed to require environmental interaction, due to conservation of momentum. However, as first noted in [J. Wisdom, Science 299, 1865-1869 (2003)] and later in [E. Guéron, Sci. Am. 301, 38-45 (2009)] and [J. Avron, O. Kenneth, New J. Phys, 8, 68 (2006)], the noncommutativity of translations permits translation without momentum exchange in either gravitationally curved spacetime or the curved surfaces encountered by locomotors in real-world environments. To realize this idea which remained unvalidated in experiments for almost 20 y, we show that a precision robophysical apparatus consisting of motors driven on curved tracks (and thereby confined to a spherical surface without a solid substrate) can self-propel without environmental momentum exchange. It produces shape changes comparable to the environment's inverse curvatures and generates movement of [Formula: see text] cm per gait. While this simple geometric effect predominates over short time, eventually the dissipative (frictional) and conservative forces, ubiquitous in real systems, couple to it to generate an emergent dynamics in which the swimming motion produces a force that is counter-balanced against residual gravitational forces. In this way, the robot both swims forward without momentum and becomes fixed in place with a finite momentum that can be released by ceasing the swimming motion. We envision that our work will be of use in a broad variety of contexts, such as active matter in curved space and robots navigating real-world environments with curved surfaces.

10.
Toxicology ; 475: 153241, 2022 06 15.
Article in English | MEDLINE | ID: mdl-35714946

ABSTRACT

Excessive intake of arsenic (As) and fluoride (F), which are present in underground drinking water, have adverse effects on human health, and especially on the male reproductive system. In this regard, it's critical to figure out how As and F affect Leydig and Sertoli cells, which are key cells in the male reproductive system. The goal of this study was to determine the synergistic effects of co-exposure of As and F, via drinking water, on Leydig and Sertoli cells, which are models for the male reproductive system, as well as the mechanisms underlying these effects in terms of oxidative damage and apoptosis. Leydig and Sertoli cells were exposed to concentrations of 7.7 µM (0.57 ppm) As and 0.4 mM (7.24 ppm) F based on the highest daily intake of drinking water for 24 h. The present results revealed that As and/or F treatment reduced cell viability and proliferation in Leydig and Sertoli cells, elevated lactate dehydrogenase, a cytotoxicity marker, and triggered oxidative stress and apoptosis. Furthermore, it has been proven that when As and F are exposed in combination, they have a synergistic effect. In conclusion, by revealing the harmful effects of As and F on Leydig and Sertoli cells, and thus on male infertility, it is possible to reduce As and F exposure to prevent infertility after exposure to these molecules not only separately but also together. It will be considered to determine new action and action plans to reduce As and F exposure.


Subject(s)
Arsenic , Drinking Water , Arsenic/metabolism , Drinking Water/metabolism , Fluorides/toxicity , Humans , Leydig Cells , Male , Oxidative Stress , Sertoli Cells
11.
Bioinspir Biomim ; 17(4)2022 06 16.
Article in English | MEDLINE | ID: mdl-35533656

ABSTRACT

Serially connected robots are promising candidates for performing tasks in confined spaces such as search and rescue in large-scale disasters. Such robots are typically limbless, and we hypothesize that the addition of limbs could improve mobility. However, a challenge in designing and controlling such devices lies in the coordination of high-dimensional redundant modules in a way that improves mobility. Here we develop a general framework to discover templates to control serially connected multi-legged robots. Specifically, we combine two approaches to build a general shape control scheme which can provide baseline patterns of self-deformation ('gaits') for effective locomotion in diverse robot morphologies. First, we take inspiration from a dimensionality reduction and a biological gait classification scheme to generate cyclic patterns of body deformation and foot lifting/lowering, which facilitate the generation of arbitrary substrate contact patterns. Second, we extend geometric mechanics, which was originally introduced to study swimming at low Reynolds numbers, to frictional environments, allowing the identification of optimal body-leg coordination in this common terradynamic regime. Our scheme allows the development of effective gaits on flat terrain with diverse numbers of limbs (4, 6, 16, and even 0 limbs) and backbone actuation. By properly coordinating the body undulation and leg placement, our framework combines the advantages of both limbless robots (modularity and narrow profile) and legged robots (mobility). Our framework can provide general control schemes for the rapid deployment of general multi-legged robots, paving the way toward machines that can traverse complex environments. In addition, we show that our framework can also offer insights into body-leg coordination in living systems, such as salamanders and centipedes, from a biomechanical perspective.


Subject(s)
Robotics , Animals , Extremities , Gait , Locomotion , Urodela
12.
Support Care Cancer ; 30(1): 749-756, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34370103

ABSTRACT

PURPOSE: To identify cancer patients' palliative care needs with problem burden, problem intensity, and felt needs related to these problems while receiving cancer treatment. METHODS: This is a descriptive survey study conducted at a tertiary hospital with no palliative care services in Istanbul, Turkey, from September 2019 to February 2020. Data were collected using the Patient Information Form and the Three Levels of Needs Questionnaire (3LNQ). Descriptive statistics (frequency and percentage) were used to present data. RESULTS: The mean age of patients was 60.2 ± 13.0, and the mean duration since the diagnosis was 11.6 ± 21.4 months. Of the patients, 40.4% were diagnosed with gastrointestinal (GI) cancer, and 34.4% had stage 4 cancer. Patients mostly received help for their pain (85.7%), lack of appetite (64.8%), and nausea (73/7%). The most frequent unmet needs were problems with concentration (70%), worrying (68%), difficulties with sex life (63.6%), problems with being limited in work and daily activities (61.4%), and being depressed (58.5%) among patients who reported to have these symptoms. CONCLUSION: This study shows that patients with cancer require supportive and palliative care along with medical treatment for cancer and its treatment-induced physical and psychological symptoms. The study results have the potential to guide the development of palliative care services, especially for outpatient oncology settings in countries where palliative care services mostly focus on the end-of-life care. Further studies are also needed to focus on interventions to meet cancer patients' palliative care needs during the medical cancer treatment process with tailored palliative care delivery models.


Subject(s)
Hospice Care , Neoplasms , Terminal Care , Child , Child, Preschool , Humans , Neoplasms/epidemiology , Neoplasms/therapy , Palliative Care , Surveys and Questionnaires
13.
Acta Biomed ; 92(4): e2021241, 2021 09 02.
Article in English | MEDLINE | ID: mdl-34487104

ABSTRACT

Background The management of ankle sprains is common practice in emergency departments. Traditionally, physicians would order radiographs for all ankle injuries although the overall incidence of fractures are less than 15% .  The Ottawa Ankle Rules (OAR) have been developed to predict the necessity of radiographs in acute ankle injuries. Material and Method This is a prospective study of consecutive patients aged 16 years or older with acute non-penetrating ankle or foot injuries and who had a radiography of ankle or foot or both. Results 499 cases were included in the study. 56.90 % of the patients were male and the median age of the patients was 30 (IQR  22,44).  22.85 % (114/499) of patients with ankle or midfoot injuries had fractures.  The sensitivity, specificity, PPV and NPV of OAR for ankle and midfoot injuries  were 100, 45.26, 26.00, 100 and 100, 43.71, 19.92 and 100 respectively. In this study 792 x rays were ordered from 499 patients. According to OAR 509  (%64.27) of them were indicated whereas 283 (% 35.73) were not. When the weight bearing test is sole criteria 303 ( 38.26%) x rays were obtained to find out three fractures. Conclusion OAR should be safely used in emergency departments. Implantation of this rule prevents patients from unnecessary radiation exposure. It is a reasonable approach to reassess the patient if symptoms not resolve several days later  for avoiding unnecessary x ray exposure when the weight bearing test exist as the only positive criteria.


Subject(s)
Ankle Injuries , Foot Injuries , Fractures, Bone , Ankle , Ankle Injuries/diagnostic imaging , Emergency Service, Hospital , Foot Injuries/diagnostic imaging , Fractures, Bone/diagnostic imaging , Fractures, Bone/epidemiology , Humans , Male , Prospective Studies , Sensitivity and Specificity
14.
Bioinspir Biomim ; 17(1)2021 11 30.
Article in English | MEDLINE | ID: mdl-34496355

ABSTRACT

Earthworms (Lumbricus terrestris) are characterized by soft, highly flexible and extensible bodies, and are capable of locomoting in most terrestrial environments. Previous studies of earthworm movement focused on the use of retrograde peristaltic gaits in which controlled contraction of longitudinal and circular muscles results in waves of shortening/thickening and thinning/lengthening of the hydrostatic skeleton. These waves can propel the animal across ground as well as into soil. However, worms benefit from axial body bends during locomotion. Such lateral bending and buckling dynamics can aid locomotor function via hooking/anchoring (to provide propulsion), modify travel orientation (to avoid obstacles and generate turns) and even generate snake-like undulatory locomotion in environments where peristaltic locomotion results in poor performance. To the best of our knowledge, lateral bending and buckling of an earthworm's body has not yet been systematically investigated. In this study, we observed that within confined environments, worms use lateral bending and buckling to anchor their body to the walls of their burrows and tip (anterior end) bending to search the environment. This locomotion strategy improved the performance of our soft-bodied robophysical model of the earthworm both in a confined (in an acrylic tube) and above-ground heterogeneous environment (rigid pegs), where present peristaltic robots are relatively limited in terradynamic capabilities. In summary, lateral bending and buckling facilitates the mobility of earthworm locomotion in diverse terrain and can play an important role in the creation of low cost soft robotic devices capable of traversing a variety of environments.


Subject(s)
Oligochaeta , Robotic Surgical Procedures , Robotics , Animals , Gait , Locomotion/physiology , Oligochaeta/physiology , Robotics/methods
15.
Bioinspir Biomim ; 16(6)2021 09 01.
Article in English | MEDLINE | ID: mdl-34359055

ABSTRACT

Locomotion at the microscale is remarkably sophisticated. Microorganisms have evolved diverse strategies to move within highly viscous environments, using deformable, propulsion-generating appendages such as cilia and flagella to drive helical or undulatory motion. In single-celled algae, these appendages can be arranged in different ways around an approximately 10 µm long cell body, and coordinated in distinct temporal patterns. Inspired by the observation that some quadriflagellates (bearing four flagella) have an outwardly similar morphology and flagellar beat pattern, yet swim at different speeds, this study seeks to determine whether variations in swimming performance could arise solely from differences in swimming gait. Robotics approaches are particularly suited to such investigations, where the phase relationships between appendages can be readily manipulated. Here, we developed autonomous, algae-inspired robophysical models that can self-propel in a viscous fluid. These macroscopic robots (length and width = 8.5 cm, height = 2 cm) have four independently actuated 'flagella' (length = 13 cm) that oscillate under low-Reynolds number conditions (Re∼O(10-1)). We tested the swimming performance of these robot models with appendages arranged two distinct configurations, and coordinated in three distinct gaits. The gaits, namely the pronk, the trot, and the gallop, correspond to gaits adopted by distinct microalgal species. When the appendages are inserted perpendicularly around a central 'body', the robot achieved a net performance of 0.15-0.63 body lengths per cycle, with the trot gait being the fastest. Robotic swimming performance was found to be comparable to that of the algal microswimmers across all gaits. By creating a minimal robot that can successfully reproduce cilia-inspired drag-based swimming, our work paves the way for the design of next-generation devices that have the capacity to autonomously navigate aqueous environments.


Subject(s)
Robotics , Swimming , Flagella , Gait , Locomotion
16.
Sci Robot ; 6(56)2021 07 28.
Article in English | MEDLINE | ID: mdl-34321347

ABSTRACT

Swarms of ground-based robots are presently limited to relatively simple environments, which we attribute in part to the lack of locomotor capabilities needed to traverse complex terrain. To advance the field of terradynamically capable swarming robotics, inspired by the capabilities of multilegged organisms, we hypothesize that legged robots consisting of reversibly chainable modular units with appropriate passive perturbation management mechanisms can perform diverse tasks in variable terrain without complex control and sensing. Here, we report a reconfigurable swarm of identical low-cost quadruped robots (with directionally flexible legs and tail) that can be linked on demand and autonomously. When tasks become terradynamically challenging for individuals to perform alone, the individuals suffer performance degradation. A systematic study of performance of linked units leads to new discoveries of the emergent obstacle navigation capabilities of multilegged robots. We also demonstrate the swarm capabilities through multirobot object transport. In summary, we argue that improvement capabilities of terrestrial swarms of robots can be achieved via the judicious interaction of relatively simple units.

17.
Sci Robot ; 6(55)2021 06 16.
Article in English | MEDLINE | ID: mdl-34135117

ABSTRACT

Robotic navigation on land, through air, and in water is well researched; numerous robots have successfully demonstrated motion in these environments. However, one frontier for robotic locomotion remains largely unexplored-below ground. Subterranean navigation is simply hard to do, in part because the interaction forces of underground motion are higher than in air or water by orders of magnitude and because we lack for these interactions a robust fundamental physics understanding. We present and test three hypotheses, derived from biological observation and the physics of granular intrusion, and use the results to inform the design of our burrowing robot. These results reveal that (i) tip extension reduces total drag by an amount equal to the skin drag of the body, (ii) granular aeration via tip-based airflow reduces drag with a nonlinear dependence on depth and flow angle, and (iii) variation of the angle of the tip-based flow has a nonmonotonic effect on lift in granular media. Informed by these results, we realize a steerable, root-like soft robot that controls subterranean lift and drag forces to burrow faster than previous approaches by over an order of magnitude and does so through real sand. We also demonstrate that the robot can modulate its pullout force by an order of magnitude and control its direction of motion in both the horizontal and vertical planes to navigate around subterranean obstacles. Our results advance the understanding and capabilities of robotic subterranean locomotion.

18.
Support Care Cancer ; 29(11): 6481-6493, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33905013

ABSTRACT

PURPOSE: This study aimed to explore the impacts of the COVID-19 pandemic on the quality of life of breast cancer survivors. METHODS: This qualitative descriptive study included 18 breast cancer survivors who completed cancer treatment within the last five years in Istanbul, Turkey. A directed content analysis was performed using the quality-of-life domains as guiding themes. RESULTS: The mean age was 51 ± 5.9, and the average months since active treatment were 26.5 ± 9.8 (9-48). Six themes and associated categories are as follows: Physical functioning; Changes in physical activity and weight, new physical symptoms, Role functioning; Work-life, changes in household chores, Emotional functioning; Emotional changes, fear of having the COVID-19 infection, Cognitive Functioning; Risk Perception about the COVID-19 infection, reactions to the COVID-19 pandemic' measures, Social Functioning; Familial relationship changes, social interactions, General Health/Utilization of Healthcare services; Changes in routine follow-ups, changes in diet. CONCLUSION: Breast cancer survivors had different challenges causing new physical and psychological symptoms such as lymphedema, pain, burnout, and anxiety that may have long-term effects on their quality of life.


Subject(s)
Breast Neoplasms , COVID-19 , Cancer Survivors , Breast Neoplasms/epidemiology , Child, Preschool , Female , Humans , Pandemics , Quality of Life , SARS-CoV-2
19.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Article in English | MEDLINE | ID: mdl-33608460

ABSTRACT

Early root growth is critical for plant establishment and survival. We have identified a molecular pathway required for helical root tip movement known as circumnutation. Here, we report a multiscale investigation of the regulation and function of this phenomenon. We identify key cell signaling events comprising interaction of the ethylene, cytokinin, and auxin hormone signaling pathways. We identify the gene Oryza sativa histidine kinase-1 (HK1) as well as the auxin influx carrier gene OsAUX1 as essential regulators of this process in rice. Robophysical modeling and growth challenge experiments indicate circumnutation is critical for seedling establishment in rocky soil, consistent with the long-standing hypothesis that root circumnutation facilitates growth past obstacles. Thus, the integration of robotics, physics, and biology has elucidated the functional importance of root circumnutation and uncovered the molecular mechanisms underlying its regulation.


Subject(s)
Gene Expression Regulation, Plant , Histidine Kinase/metabolism , Indoleacetic Acids/pharmacology , Oryza/growth & development , Plant Proteins/metabolism , Plant Roots/growth & development , Soil/chemistry , Biological Transport , Cytokinins/metabolism , Histidine Kinase/genetics , Oryza/drug effects , Oryza/genetics , Oryza/metabolism , Plant Growth Regulators/pharmacology , Plant Proteins/genetics , Plant Roots/drug effects , Plant Roots/genetics , Plant Roots/metabolism
20.
Proc Natl Acad Sci U S A ; 118(6)2021 02 09.
Article in English | MEDLINE | ID: mdl-33547237

ABSTRACT

Living systems at all scales aggregate in large numbers for a variety of functions including mating, predation, and survival. The majority of such systems consist of unconnected individuals that collectively flock, school, or swarm. However, some aggregations involve physically entangled individuals, which can confer emergent mechanofunctional material properties to the collective. Here, we study in laboratory experiments and rationalize in theoretical and robophysical models the dynamics of physically entangled and motile self-assemblies of 1-cm-long California blackworms (Lumbriculus variegatus, Annelida: Clitellata: Lumbriculidae). Thousands of individual worms form braids with their long, slender, and flexible bodies to make a three-dimensional, soft, and shape-shifting "blob." The blob behaves as a living material capable of mitigating damage and assault from environmental stresses through dynamic shape transformations, including minimizing surface area for survival against desiccation and enabling transport (negative thermotaxis) from hazardous environments (like heat). We specifically focus on the locomotion of the blob to understand how an amorphous entangled ball of worms can break symmetry to move across a substrate. We hypothesize that the collective blob displays rudimentary differentiation of function across itself, which when combined with entanglement dynamics facilitates directed persistent blob locomotion. To test this, we develop a robophysical model of the worm blobs, which displays emergent locomotion in the collective without sophisticated control or programming of any individual robot. The emergent dynamics of the living functional blob and robophysical model can inform the design of additional classes of adaptive mechanofunctional living materials and emergent robotics.


Subject(s)
Annelida/physiology , Robotics , Animals , Desiccation , Imaging, Three-Dimensional , Locomotion , Models, Biological , Phototaxis/physiology , Stress, Physiological , Taxis Response/physiology , Temperature , Volatilization , Water
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