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1.
PLoS One ; 18(12): e0295823, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38128010

RESUMEN

The study of plant root growth in real time has been difficult to achieve in an automated, high-throughput, and systematic fashion. Dynamic imaging of plant roots is important in order to discover novel root growth behaviors and to deepen our understanding of how roots interact with their environments. We designed and implemented the Generating Rhizodynamic Observations Over Time (GROOT) robot, an automated, high-throughput imaging system that enables time-lapse imaging of 90 containers of plants and their roots growing in a clear gel medium over the duration of weeks to months. The system uses low-cost, widely available materials. As a proof of concept, we employed GROOT to collect images of root growth of Oryza sativa, Hudsonia montana, and multiple species of orchids including Platanthera integrilabia over six months. Beyond imaging plant roots, our system is highly customizable and can be used to collect time- lapse image data of different container sizes and configurations regardless of what is being imaged, making it applicable to many fields that require longitudinal time-lapse recording.


Asunto(s)
Oryza , Robótica , Raíces de Plantas , Montana
2.
Turk J Chem ; 47(2): 465-475, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37528929

RESUMEN

Turkey is the world's leading producer of figs, a typical Mediterranean fruit. The fig, Ficus carica L. (Moraceae), has been widely cultivated since ancient times due to the nutritional value of its fruits. It was aimed to investigate the phytochemical characterization and biological properties of F. carica leaf extracts in order to determine their potential for use in the treatment of various diseases. F. carica leaves were extracted in 70% methanol at 40 °C under reflux. To obtain extracts of different polarities, the crude extract was fractionated with n-hexane, dichloromethane, and n-butanol. Phenolic content was determined using liquid chromatography-high resolution mass spectrometry (LC-HRMS). 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and antityrosinase activities of all extracts were investigated using spectrophotometric methods. Furthermore, the DNA-damage protective properties of extracts were investigated using electrophoretic methods. The n-butanol extract was found to have the highest total phenolic content, with 72.58 ± 4.52 mg GAE/g dry weight. According to LC-HRMS analysis, rutin (40.13 g/kg) was the most abundant compound in the n-butanol extract. The n-butanol extract, which was found to have the highest tyrosinase inhibitory effects among the extracts, demonstrated radical scavenging activity of 37.01 ± 1.15% and 82.57 ± 0.88% at 80 and 200 µg/mL, respectively. The n-butanol extract had the highest protective effects against Fenton's reagent, UV radiation, and singlet oxygen. Given these findings, it is possible to argue that F. carica leaves can be evaluated for developing products that could be used to treat various diseases.

3.
J Craniofac Surg ; 34(3): 881-883, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36731089

RESUMEN

AIM: The aim of this study is to examine the effects of the burr used for hump reduction and osteoplasty on cochlear function. MATERIALS AND METHODS: The design of this study was prospective, randomized, and controlled. Twenty patients who underwent burr-assisted septorhinoplasty were included in the study group. The control group consisted of 20 patients who underwent septoplasty. Pure tone audiometry, distortion product otoacoustic emission test, and tympanometry were performed to determine the auditory functions. RESULTS: No significant difference was observed between the bone conduction thresholds of the right and left ears in both groups, except for a single frequency (1000 Hz in the left ear) in the control group. There was no significant difference between the 2 groups' air conduction thresholds at frequencies of 500, 1000, 2000, 4000, 6000, and 8000 Hz preoperatively and postoperatively. In addition, the study and control group did not differ significantly in signal-to-noise ratio measurements at frequencies of 500, 1000, 2000, and 4000 Hz. The comparison of preoperative and postoperative otoacoustic emission measurement results of the study group revealed a statistically significant difference only at the frequencies of 2000 Hz in the right ear and 500 Hz in the left ear. Despite those differences, otoacoustic emissions were still present at those frequencies postoperatively. CONCLUSIONS: Our study showed that using burrs during rhinoplasty slightly impacts hearing, but it does not cause significant hearing loss. Burr-assisted rhinoplasty appears to be a safe operation regarding the auditory functions.


Asunto(s)
Umbral Auditivo , Conducción Ósea , Cóclea , Tabique Nasal , Rinoplastia , Estudios Prospectivos , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Persona de Mediana Edad , Rinoplastia/efectos adversos , Cóclea/fisiología , Pruebas de Impedancia Acústica , Tabique Nasal/cirugía , Instrumentos Quirúrgicos
4.
J Int Adv Otol ; 18(6): 478-481, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36349668

RESUMEN

BACKGROUND: It is aimed to investigate the incidence of cerebrospinal fluid gusher in cochlear implantation and the association between cerebrospinal fluid gusher and inner-ear malformations in adult and pediatric patients. METHODS: A retrospective case review of 1025 primary cochlear implantation procedures was performed. Patients with inner-ear malformation or cerebrospinal fluid gusher during primary cochlear implantation were included and divided into 2 groups according to age: pediatric and adult groups. RESULTS: The incidence of inner-ear malformation was 4.19% (17/405) and 7.6% (47/620) in the adult and pediatric groups, respectively. There was a significant difference in the incidence of inner-ear malformation in the pediatric group. The incidence of cerebrospinal fluid gusher was 0.9% (4/405) and 4.1% (26/620) in the adult and pediatric groups, respectively. There was a significant difference in the incidence of gusher between the adult and pediatric groups. CONCLUSION: The incidence of a cerebrospinal fluid gusher is higher in the pediatric group, compared to adults due to a higher rate of inner-ear malformation. Inner-ear malformation poses a risk factor for cerebrospinal fluid gusher.


Asunto(s)
Implantación Coclear , Implantes Cocleares , Oído Interno , Adulto , Humanos , Niño , Implantación Coclear/métodos , Estudios Retrospectivos , Oído Interno/cirugía , Oído Interno/anomalías , Implantes Cocleares/efectos adversos , Otorrea de Líquido Cefalorraquídeo/epidemiología , Otorrea de Líquido Cefalorraquídeo/etiología
5.
Proc Natl Acad Sci U S A ; 119(31): e2200924119, 2022 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-35901212

RESUMEN

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.

6.
Bioinspir Biomim ; 17(4)2022 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-35533656

RESUMEN

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.


Asunto(s)
Robótica , Animales , Extremidades , Marcha , Locomoción , Urodelos
7.
J Craniofac Surg ; 33(2): 418-420, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34267133

RESUMEN

ABSTRACT: Septorhinoplasty is one of the most common elective surgical procedures in otolaryngology. The present study aimed to evaluate the anxiety levels of patients who underwent septorhinoplasty at different times, compare the information methods, and determine the understanding of the informed consent through recall rates of the complications explained in the informed consent process. The patients were divided into the following 2 groups: Group 1 (giving information 14 days before the surgery) and Group 2 (giving information 3 days before the surgery). For the preoperative anxiety measurement, the State anxiety scale of the State-Trait Anxiety Inventory (STAI) was used. All patients were asked to recall the complications they remembered from the consent form on the day before the surgery. Each group has consisted of 25 patients. No significant difference was found between the STAI-1 and STAI-2a anxiety scores between groups. In Group 1, the STAI-2b anxiety score was significantly lower than the STAI-1 and STAI-2a scores (P < 0.05). In Group 2, the mean score of STAI-2b was not significantly higher than the STAI-1 and STAI-2 scores (P > 0.05). When the STAI-2b scores of the two groups were compared, the scores of Group 2 were significantly higher (P < 0.05). The most commonly remembered complications were bruising and swelling in both of the groups. In conclusion, the authors believe that long-term cooperation between the surgical team and the patient will reduce the anxiety levels of the patients and increase patients' satisfaction, resulting in a significant reduction in the amount of potential legal processes.Level of Evidence: 2.


Asunto(s)
Rinoplastia , Ansiedad , Procedimientos Quirúrgicos Electivos , Humanos , Consentimiento Informado , Satisfacción del Paciente
8.
Bioinspir Biomim ; 16(6)2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34359055

RESUMEN

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.


Asunto(s)
Robótica , Natación , Flagelos , Marcha , Locomoción
9.
Sci Robot ; 6(55)2021 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-34135117

RESUMEN

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.

10.
Sci Adv ; 7(17)2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33893101

RESUMEN

At the macroscale, controlling robotic swarms typically uses substantial memory, processing power, and coordination unavailable at the microscale, e.g., for colloidal robots, which could be useful for fighting disease, fabricating intelligent textiles, and designing nanocomputers. To develop principles that can leverage physical interactions and thus be used across scales, we take a two-pronged approach: a theoretical abstraction of self-organizing particle systems and an experimental robot system of active cohesive granular matter that intentionally lacks digital electronic computation and communication, using minimal (or no) sensing and control. As predicted by theory, as interparticle attraction increases, the collective transitions from dispersed to a compact phase. When aggregated, the collective can transport non-robot "impurities," thus performing an emergent task driven by the physics underlying the transition. These results reveal a fruitful interplay between algorithm design and active matter robophysics that can result in principles for programming collectives without the need for complex algorithms or capabilities.

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