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Lymphedema is known to affect as many as 140 to 250 million people worldwide. Approximately 99% of lymphedemas are secondary cases after lymphadenectomy, radiation, or parasite infection. There has been no accurate estimate of the lymphedema population size in South Korea. This study aimed to quantify the epidemiology of lymphedema in South Korea and analyze the clinical characteristics of patients with lymphedema using a nationwide database. This large-scale cross-sectional study included patients who received one of the following three diagnostic codes - Q82.0 (hereditary lymphedema), I97.2 (breast cancer-related lymphedema), and I89.0 (unclassified lymphedema) from the Korean Health Insurance Review and Assessment service between January 2019 and July 2022 at tertiary hospitals, general hospitals, or other hospitals. The demographics of the lymphedema population, medication use, and medical characteristics were identified. Over the last 4 years, the annual incidence of lymphedema has steadily increased and peaked in 2021 with the number 1.85 out of 1000. Of all patients, 81% were located in the upper extremity, and 10.6% had previous cancer. Most patients were diagnosed in general hospitals (53.2%), at orthopedic surgery department (41.9%). On average, lymphedema patients spent 70.17 US dollar for medication and hospitalized for 16.9 days annually after diagnosis. Commonly prescribed medications were Entelon® (Vitis vinifera seed extract) (66.9%), steroids (40.5%), non-steroidal anti-inflammatory drugs (26.5%) and diuretics (21.8%). Only 5.7% of patients received surgery and 19.2% received herbal medicine. This is the first study in South Korea to quantify demographic and medical characteristics of lymphedema patients. These results will contribute to a comprehensive understanding of lymphedema diagnosis and treatment in our nation.
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Linfedema , Humanos , República de Corea/epidemiología , Estudios Transversales , Femenino , Masculino , Linfedema/epidemiología , Persona de Mediana Edad , Adulto , Anciano , Incidencia , Adolescente , Adulto JovenRESUMEN
The superficial temporal artery (STA) bifurcates into frontal and parietal branches. The parietal branch is used as a recipient vessel for scalp reconstruction, but it is absent in approximately 16.3% of individuals. In this case, a 72-year-old woman with an occipital scalp defect lacked both the parietal branch of the STA and the superficial temporal vein. To address this anatomic variation, we used the frontal branch of the STA and the posterior auricular vein as alternative recipient vessels for anterolateral thigh free flap reconstruction. The surgical procedure involved end-to-end microvascular anastomosis of one artery and one vein. Partial flap necrosis occurred postoperatively, but eventually resolved with debridement. The frontal branch of the STA and the posterior auricular vein can serve as reliable alternatives in the absence of the parietal branch. Reconstructive surgeons should be aware of anatomic variations of the STA and adapt their surgical approach accordingly.
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The enrichment of phosphorus (P) and nitrogen (N) in aquatic systems can cause eutrophication. Moreover, P rocks may become exhausted in the next 100 years. A slow-release fertilizer called struvite (MgNH4PO4.6H2O) can reduce surface runoff. However, the high cost of raw material or chemicals is a bottleneck in their economical production. Therefore, incinerated sewage sludge ash, food wastewater, and bittern were combined as the sources of P, N, and Mg, respectively. Sawdust biochar was used to enhance the adsorptive recovery of nutrients. First, recovery kinetics was studied by comparing bittern-impregnated biochar (BtB) with the Mg-impregnated biochar (MgB). Subsequently, the synergistic physical and chemical interactions were observed for P and N recovery. Almost complete PO43-P recoveries were achieved within 10 min for both biochars. However, NH4+-N recovery was stable after 2 h, with 26% recovery by MgB and 20% recovery by BtB. Biochars activated with steam (steam-activated biochar) and KOH (KOH-activated biochar) gave superior activities to those of unactivated biochars and activated carbon (AC) nutrient recovery and struvite purity. Moreover, the activated biochars showed a lower risk of surface runoff, similar to that of AC. Therefore, activated biochars can be used as an alternative to AC for economical struvite production from a combination of wastewater sources.
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Carbón Orgánico , Fertilizantes , Nitrógeno , Fósforo , Estruvita , Eliminación de Residuos Líquidos , Aguas Residuales , Estruvita/química , Carbón Orgánico/química , Aguas Residuales/química , Fósforo/química , Fósforo/análisis , Nitrógeno/química , Nitrógeno/análisis , Fertilizantes/análisis , Eliminación de Residuos Líquidos/métodos , Nutrientes/análisis , Aguas del Alcantarillado/química , Adsorción , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Compuestos de Magnesio/química , Fosfatos/químicaRESUMEN
Scalp avulsion is a devastating injury. The best possible procedure is replantation. Several successful scalp replantations with anastomoses of several vessels in large defects have been reported. In this report, we present a case of replantation of a large scalp avulsion using revascularizing with only one artery and vein. Despite the initial signs of flap congestion, we could predict the survival of the replanted scalp and terminate the procedure after detecting good perfusion and washout with indocyanine green fluorescence imaging. The procedure was successful following the patient's recovery of sensory and sweating functions without complications such as flap necrosis or infection. Several important factors for successful scalp replantation with positive esthetic and functional outcomes were considered.
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South Korea is promoting digital healthcare services in the public sector. One notable initiative is the "artificial intelligence and the internet of things (AI-IoT)-based healthcare project for senior citizens", which was implemented by the Korea Health Promotion Institute (KHPI). This project utilized an IoT-based digital healthcare service that integrates information technology and screen-based AI speaker functions. Services through this project are intended for senior citizens aged 65 years (or older) who face challenges in visiting public healthcare institutions owing to limitations on outdoor activities, especially in the post-coronavirus 2019 era. This article shares the recent outcomes of this project and outlines the mid-to-long-term development strategies for this style of South Korean digital healthcare initiatives.
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PURPOSE: Triple-negative breast cancer (TNBC) is a breast cancer subtype that has poor prognosis and exhibits a unique tumor microenvironment. Analysis of the tumor microbiome has indicated a relationship between the tumor microenvironment and treatment response. Therefore, we attempted to reveal the role of the tumor microbiome in patients with TNBC receiving neoadjuvant chemotherapy. MATERIALS AND METHODS: We collected TNBC patient RNA-sequencing samples from the Gene Expression Omnibus and extracted microbiome count data. Differential and relative abundance were estimated with linear discriminant analysis effect size. We calculated the immune cell fraction with CIBERSORTx and conducted survival analysis using the Cancer Genome Atlas patient data. Correlations between the microbiome and immune cell compositions were analyzed and a prediction model was constructed to estimate drug response. RESULTS: Among the pathological complete response group (pCR), the beta diversity varied considerably; consequently, 20 genera and 24 species were observed to express a significant differential and relative abundance. Pandoraea pulmonicola and Brucella melitensis were found to be important features in determining drug response. In correlation analysis, Geosporobacter ferrireducens, Streptococcus sanguinis, and resting natural killer cells were the most correlated factors in the pCR, whereas Nitrosospira briensis, Plantactinospora sp. BC1, and regulatory T cells were key features in the residual disease group. CONCLUSION: Our study demonstrated that the microbiome analysis of tumor tissue can predict chemotherapy response of patients with TNBC. Further, the immunological tumor microenvironment may be impacted by the tumor microbiome, thereby affecting the corresponding survival and treatment response.
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Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética , Terapia Neoadyuvante , Microambiente Tumoral , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , PronósticoRESUMEN
BACKGROUND: Transgender and intersex populations have long remained under-documented in South Korea, largely due to the absence of comprehensive epidemiological data. With increasing societal acknowledgment, there's an urgent need to understand the demographics and health challenges faced by these communities. METHODS: This retrospective, large-scale data study included people who received the F64 codes from the Korean Health Insurance Review & Assessment Service between January 2007 and December 2021. Demographics, gender-affirmative treatments, and psychiatric related medications were examined. RESULTS: Between 2007 and 2021, 8,602 patients were diagnosed with "gender identity disorder" and 45 with "intersex." A steadily increasing annual prevalence was observed, peaking at 986 cases in 2021. The majority (79.8%) were aged between 10 and 30. Nearly half (53.2%) exhibited mental and behavioral disorders. Two-thirds had been prescribed anxiolytics or sedatives either before or after diagnosis. Merely 12.1% received hormone therapy covered by health insurance. CONCLUSION: This is the first large-scale study highlighting the demographics and clinical characteristics of the transgender and intersex populations in Korea. The study reveals a consistent growth of these communities over the past 15 years, with a significant proportion under 30 years of age facing mental and behavioral challenges. Findings underscore the need for targeted healthcare interventions, early psychological support, and comprehensive insurance coverage tailored to the specific needs of these individuals in Korea.
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Trastornos Mentales , Personas Transgénero , Humanos , Niño , Adolescente , Adulto Joven , Adulto , Personas Transgénero/psicología , Estudios Retrospectivos , República de Corea/epidemiología , Demografía , Factores de Transcripción , Proteínas de Ciclo Celular , Chaperonas de HistonasRESUMEN
The objective of this study is to investigate the correlation between the neighborhood deprivation index and survival rates of cancer patients in Korea. In this study, 5-year age-standardized survival rates of patients with cancer were determined using the National Cancer Cohort from 2014 to 2018 in Korea. The primary cancer sites were the stomach, colorectum, liver, lung, breast, cervix, prostate, and thyroid. Disparities were measured, and their impact on the overall survival rates was assessed using the Korean version of the Neighborhood Deprivation Index. Pearson's correlation coefficient was calculated to determine the strength of the correlation. The study cohort comprised 726,665 patients with cancer, of whom 50.7% were male. The predominant primary cancer sites were the stomach (n = 138,462), colorectum (n = 125,156), and thyroid gland (n = 120,886). Urban residents showed better survival outcomes than those situated in rural areas. The most deprived quartile had the lowest survival rate, while the least deprived quartile had the highest (p < 0.001). Most cancer types revealed significant correlations between neighborhood deprivation and 5-year age-standardized overall survival, with lung cancer showing the most substantial negative correlation (r = -0.510), followed by prostate cancer (r = -0.438). However, thyroid cancer showed only a marginal correlation (p = 0.069). The results of this study suggested that neighborhood deprivation is closely linked to disparities in overall survival across various types of cancer. A substantial negative correlation between the neighborhood deprivation index and all-cause mortality for lung and prostate cancer, as compared to breast and cervical cancers covered by the National Cancer Screening Program, may reinforce the need to address healthcare access and improve the early detection of cancer in socioeconomically deprived neighborhoods.
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X-ray structural science is undergoing a revolution driven by the emergence of X-ray Free-electron Laser (XFEL) facilities. The structures of crystalline solids can now be studied on the picosecond time scale relevant to phonons, atomic vibrations which travel at acoustic velocities. In the work presented here, X-ray diffuse scattering is employed to characterize the time dependence of the liquid phase emerging from femtosecond laser-induced melting of polycrystalline gold thin films using an XFEL. In a previous analysis of Bragg peak profiles, we showed the supersonic disappearance of the solid phase and presented a model of pumped hot electrons carrying energy from the gold surface to scatter at internal grain boundaries. This generates melt fronts propagating relatively slowly into the crystal grains. By conversion of diffuse scattering to a partial X-ray pair distribution function, we demonstrate that it has the characteristic shape obtained by Fourier transformation of the measured F(Q). The diffuse signal fraction increases with a characteristic rise-time of 13â ps, roughly independent of the incident pump fluence and consequent final liquid fraction. This suggests the role of further melt-front nucleation processes beyond grain boundaries.
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RATIONALE: The RoboticScope (BHS Technologies GmbH, Innsbruck, Austria) is a robotic exoscope, which consists of a robotic arm that holds a 3-dimensional camera. It has an advantage that a surgeon can perform an operation comfortably with a favorable ergonomic position. Also, it allows the delivery of clear and high-quality visualization for surgeons. In this study, we would like to share our initial experience with this newly developed microscope technology in lymphaticovenular anastomosis (LVA). To the best of our knowledge, it is the first experience of LVA using this microscope in Asia. PATIENT CONCERNS: A 65-year-old woman presented with bilateral lower extremity lymphedema after a hysterectomy that was performed 25 years back. Despite complex decongestive physiotherapy, an edematous symptom in both legs worsened. DIAGNOSES: In lymphoscintigraphy, a decreased visualization of main lymphatic flow in both the lower extremities was evident which was further suggestive of lymphatic obstruction. INTERVENTION: Although both sides showed edematous symptoms, we decided to proceed with the surgery on the left side first, because of the worsened condition. Four LVAs were performed at the dorsum of the foot (×2), ankle, and the superior edge of the knee using RoboticScope. OUTCOMES: At 6-months follow-up after operation, the postoperative circumference diameters were improved than preoperative in 10 cm above the knee (45 cm vs 49 cm), 10cm below the knee (37 cm vs 41 cm) and lateral malleolus (25 cm vs 28 cm). The lower extremity lymphedema index was also improved from 346.7 to 287.4 postoperatively. The RoboticScope provided a high-resolution image and a favorable ergonomic position during an operation. LESSONS: The results represent the possibility of the application of a robotic microscope in the field of microsurgery, and further studies are necessitated to confirm the efficacy of this system.
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Vasos Linfáticos , Linfedema , Femenino , Humanos , Anciano , Extremidad Inferior/cirugía , Linfedema/cirugía , Linfedema/etiología , Vasos Linfáticos/diagnóstico por imagen , Vasos Linfáticos/cirugía , Pierna/cirugía , Anastomosis Quirúrgica/métodos , Microcirugia/métodosRESUMEN
Momentum transfer from the water surface is strongly related to the dynamical scale and morphology of jumping animals. Here, we investigate the scale-dependent momentum transfer of various jumping organisms and engineered systems at an air-water interface. A simplified analytical model for calculating the maximum momentum transfer identifies an intermediate dynamical scale region highly disadvantageous for jumping on water. The Weber number of the systems should be designed far from 1 to achieve high jumping performance on water. We design a relatively large water-jumping robot in the drag-dominant scale range, having a high Weber number, for maximum jumping height and distance. The jumping robot, around 10 times larger than water striders, has a take-off speed of 3.6 m/s facilitated by drag-based propulsion, which is the highest value reported thus far. The scale-dependent hydrodynamics of water jumpers provides a useful framework for understanding nature and robotic system interacting with the water surface.
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Novel clay (bentonite) supported Ag0 nanoparticles (NPs) doped TiO2 nanocomposite (Clay/TiO2/Ag0(NPs)) thin film was obtained by using template synthesis method. The nanocomposite material is decorated with cubical Ag0(NPs) and utilised successfully in the photocatalytic degradation of tetracycline (TC) and sulfamethazine (SMZ) from aqueous solutions utilizing visible light and UV-A radiations. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS) analyses were used to characterise the nanocomposite materials. Diffusion reflectance spectroscopy (DRS) was utilised to determine the bandgap energies of the materials and also to confirm that Ag0(NPs) was successfully doped with TiO2. The nanocomposite material showed highly efficient photocatalytic activity for the breaking down of TC/SMZ under visible light irradiation by the enhanced electron-hole separation and adsorption of antibiotics at the vicinity of the catalyst. The oxidative degradation of TC/SMZ were shown to be highly dependent on the pH, initial concentration of TC/SMZ, and various co-existing ions. Reusability test of Clay/Ag0(NPs)/TiO2 nanocomposite revealed that the activity did not decline with repeated use. Treatment of TC and SMZ in real water system further enhanced the application potential of the novel catalysts for the treatment of full-scale wastewater polluted with these antibiotics.
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Antibacterianos , Nanocompuestos , Agua , Arcilla , Luz , Titanio/química , Nanocompuestos/química , Tetraciclina , CatálisisRESUMEN
Recent state-of-the-art active learning methods have mostly leveraged generative adversarial networks (GANs) for sample acquisition; however, GAN is usually known to suffer from instability and sensitivity to hyperparameters. In contrast to these methods, in this article, we propose a novel active learning framework that we call Maximum Classifier Discrepancy for Active Learning (MCDAL) that takes the prediction discrepancies between multiple classifiers. In particular, we utilize two auxiliary classification layers that learn tighter decision boundaries by maximizing the discrepancies among them. Intuitively, the discrepancies in the auxiliary classification layers' predictions indicate the uncertainty in the prediction. In this regard, we propose a novel method to leverage the classifier discrepancies for the acquisition function for active learning. We also provide an interpretation of our idea in relation to existing GAN-based active learning methods and domain adaptation frameworks. Moreover, we empirically demonstrate the utility of our approach where the performance of our approach exceeds the state-of-the-art methods on several image classification and semantic segmentation datasets in active learning setups.
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The contamination of the aquatic environment with emerging micro-pollutants is a serious global concern. The aim of this investigation was to synthesize novel functionalized material (BNAPTES) precursor to natural bentonite in a single pot facile synthetic route. The material was utilized for efficient and selective removal of tetracycline (TC) and triclosan (TCS) in aqueous wastes. The grafting of silane was confirmed with the FT-IR (Fourier Transform Infra-Red) analysis and the EDX (Energy Dispersive X-ray) analysis showed the incorporation of amino group with the bentonite. The structural changes of clay due to silane grafting were studied with the help of XRD (X-ray Diffraction) and BET (Brunner-Emmett-Teller) surface area analyses. Batch adsorption studies showed that functionalized clay significantly increased the selectivity and adsorption capacity of bentonite for TC and TCS. The Langmuir monolayer adsorption capacity was found to be 15.36 and 17.15â mg/g for TC and TCS, respectively. The rapid uptake of TC and TCS by functionalized material followed pseudo-second-rate kinetics. Further, a total of 78% of TC and 73% of TCS were removed within 5â min of contact and the adsorption equilibrium was achieved within 120 â min. The influence of background electrolytes and co-existing ions indicated that TC and TCS were selective towards BNAPTES. The loading capacities of the column packed with BNAPTES were found to be 56.00 and 44.42â mg/g for TC and TCS, respectively. Further, BNAPTES was found efficient even in real water treatment since the attenuation of TC and TCS was not affected significantly in the real water matrix.
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Triclosán , Contaminantes Químicos del Agua , Bentonita/química , Termodinámica , Arcilla , Espectroscopía Infrarroja por Transformada de Fourier , Descontaminación , Silanos , Antibacterianos , Tetraciclina , Triclosán/química , Adsorción , Cinética , Contaminantes Químicos del Agua/análisisRESUMEN
Carbon capture and utilization technology has been studied for its practical ability to reduce CO2 emissions and enable economical chemical production. The main challenge of this technology is that a large amount of thermal energy must be provided to supply high-purity CO2 and purify the product. Herein, we propose a new concept called reaction swing absorption, which produces synthesis gas (syngas) with net-zero CO2 emission through direct electrochemical CO2 reduction in a newly proposed amine solution, triethylamine. Experimental investigations show high CO2 absorption rates (>84%) of triethylamine from low CO2 concentrated flue gas. In addition, the CO Faradaic efficiency in a triethylamine supplied membrane electrode assembly electrolyzer is approximately 30% (@-200 mA cm-2), twice higher than those in conventional alkanolamine solvents. Based on the experimental results and rigorous process modeling, we reveal that reaction swing absorption produces high pressure syngas at a reasonable cost with negligible CO2 emissions. This system provides a fundamental solution for the CO2 crossover and low system stability of electrochemical CO2 reduction.
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Enzymatic deconstruction of poly(ethylene terephthalate) (PET) is under intense investigation, given the ability of hydrolase enzymes to depolymerize PET to its constituent monomers near the polymer glass transition temperature. To date, reported PET hydrolases have been sourced from a relatively narrow sequence space. Here, we identify additional PET-active biocatalysts from natural diversity by using bioinformatics and machine learning to mine 74 putative thermotolerant PET hydrolases. We successfully express, purify, and assay 51 enzymes from seven distinct phylogenetic groups; observing PET hydrolysis activity on amorphous PET film from 37 enzymes in reactions spanning pH from 4.5-9.0 and temperatures from 30-70 °C. We conduct PET hydrolysis time-course reactions with the best-performing enzymes, where we observe differences in substrate selectivity as function of PET morphology. We employed X-ray crystallography and AlphaFold to examine the enzyme architectures of all 74 candidates, revealing protein folds and accessory domains not previously associated with PET deconstruction. Overall, this study expands the number and diversity of thermotolerant scaffolds for enzymatic PET deconstruction.
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Hidrolasas , Tereftalatos Polietilenos , Hidrolasas/metabolismo , Tereftalatos Polietilenos/química , Filogenia , Hidrólisis , EtilenosRESUMEN
A simulation of quantum dot (QD) energy levels was designed to reproduce a quantum mechanical analytic method based on perturbation theory. A Schrödinger equation describing an electron-hole pair in a QD was solved, in consideration of the heterogeneity of the material parameters of the core and shell. The equation was solved numerically using single-particle basis sets to obtain the eigenstates and energies. This approach reproduced an analytic solution based on perturbation theory, while the calculation was performed using a numerical method. Owing to the effectiveness of the method, QD behavior according to the core diameter and external electric field intensity could be investigated reliably and easily. A 9.2 nm diameter CdSe/ZnS QD with a 4.2 nm diameter core and 2.5 nm thick shell emitted a 530 nm green light, according to an analysis of the effects of core diameter on energy levels. A 4 nm redshift at 5.4×105 V/cm electric field intensity was found while investigating the effects of external electric field on energy levels. These values agree well with previously reported experimental results. In addition to the energy levels and light emission wavelengths, the spatial distributions of wavefunctions were obtained. This analysis method is widely applicable for studying QD characteristics with varying structure and material compositions and should aid the development of high-performance QD technologies.
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Hydrogels have diverse chemical properties and can exhibit reversibly large mechanical deformations in response to external stimuli; these characteristics suggest that hydrogels are promising materials for soft robots. However, reported actuators based on hydrogels generally suffer from slow response speed and/or poor controllability due to intrinsic material limitations and electrode fabrication technologies. Here, we report a hydrogel actuator that operates at low voltages (<3 volts) with high performance (strain > 50%, energy density > 7 × 105 joules per cubic meter, and power density > 3 × 104 watts per cubic meter), surpassing existing hydrogel actuators and other types of electroactive soft actuators. The enhanced performance of our actuator is due to the formation of wrinkled nanomembrane electrodes that exhibit high conductivity and excellent mechanical deformation through capillary-assisted assembly of metal nanoparticles and deswelling-induced wrinkled structures. By applying an electric potential through the wrinkled nanomembrane electrodes that sandwich the hydrogel, we were able to trigger a reversible and substantial electroosmotic water flow inside a hydrogel film, which drove the controlled swelling of the hydrogel. The high energy efficiency and power density of our wrinkled nanomembrane electrode-induced actuator enabled the fabrication of an untethered insect-scale aquabot integrated with an on-board control unit demonstrating maneuverability with fast locomotion speed (1.02 body length per second), which occupies only 2% of the total mass of the robot.
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Hidrogeles , Agua , Animales , Hidrogeles/química , Electrodos , Conductividad Eléctrica , InsectosRESUMEN
The present study used a bioassay of immobilized microalgae (Chlorella vulgaris) via direct contact to assess the toxicity of eleven uncontaminated (reference) and five field contaminated soils with various physicochemical properties and contamination. Photosynthetic oxygen concentration in the headspace of the test kit by Chlorella vulgaris in the reference soils ranged between 12.93% and 14.80% and only 2.54%-7.14% in the contaminated soils, respectively. Inherent test variability (CVi) values ranged between 2.90% and 9.04%; variation due to soil natural properties (CVrs) ranged between 0.33% and 13.0%; and minimal detectable difference (MDD) values ranged from 4.69% to 11.6%. A computed toxicity threshold of 15% was established for microalgae soil toxicity tests based on calculations of the maximal tolerable inhibition (MTI). All contaminated soils were considered toxic to microalgae because their levels of inhibition ranged between 39.5% and 82.9%, exceeding the 15% toxicity threshold. It can be concluded that the elevated concentrations of heavy metals and organic contaminants in the contaminated soils induced the higher inhibitory levels. Overall, direct contact soil toxicity tests using immobilized microalgae provided coherent and repeatable data and can be utilized as a simple and suitable tool for the toxicity testing of contaminated field soils.