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Modular reconfigurable robots exhibit prominent advantages in the reconnaissance and exploration tasks within unstructured environments for their characteristics of high adaptability and high robustness. However, due to the limitations in locomotion mechanism and integration requirements, the modular design of miniature robots in the aquatic environment encounters significant challenges. Here, a modular strategy based on the synthetic jet principle is proposed, and a modular reconfigurable robot system is developed. Specialized bottom and side jet actuators are designed with vibration motors as excitation sources, and a motion module is developed incorporating the jet actuators to realize three-dimensional agile motion. Its linear, rotational, and ascending motion speeds reach 70.7 mm s-1, 3.3 rad s-1, and 28.7 mm s-1, respectively. The module integrates the power supply, communication, and control system with a small size of 48 mm × 38 mm × 38 mm, which ensures a wireless controllable motion. Then, various configurations of the multi-module robot system are established with corresponding motion schemes, and the experiments with replaceable intermediate modules are further conducted to verify the transportation and image-capturing functions. This work demonstrates the effectiveness of synthetic jet propulsion for aquatic modular reconfigurable robot systems, and it exhibits profound potential in future underwater applications.
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Vibration is a common strategy for aquatic organisms to achieve their life activities, especially at the air-water interface. For the locomotion of small creatures, the organs with plate features are often used on water surfaces, which inspires relevant studies about using thin plates for robot propulsions. However, the influence of the general deformations of thin plates on the generated flow fields has not been considered. Here, a comprehensive investigation is conducted about the flow fields that arose by vibrations of thin plates and the potential as locomotion strategies are explored. It is discovered that as thin plates are subjected to vibration excitations on the water surface, the produced flow fields are mainly determined by the vibration shapes, and the influence rules of plate deformations on the flow fields are identified. The main factors producing asymmetric flow fields are analyzed to realize the morphology control of the flow fields. Then, to determine effective locomotion strategies on the water surface, the flow fields stimulated by integrated vibration exciters are explored, and 2 water surface robots are developed consequentially, which exhibit superior motion performance. This work reveals the basic rules of the vibration-induced-flow mechanism by thin plates and establishes new locomotion strategies for aquatic robots.
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The efficient utilization of food waste (FW) resources through Food Waste Valorization (FWV) has received increasing attention in recent years. Various decision-making studies have been undertaken to facilitate FWV implementation, such as the studies on decision-making framework and FWV technology assessment. Food waste hierarchy is a widely discussed framework in FW management, but it was found too simplified and does not always contribute positively to environmental sustainability. Moreover, decision-making studies in FWV often focus on specific aspects of the food system and employ distinctive decision-making approaches, making it difficult to compare the results from different studies. Therefore, our literature review is conducted to provide a comprehensive understanding of FWV decision-making. This study identifies what decisions are needed, and three levels of decisions are revealed: system-level, FW stream-level, and FWV option-level. The assessment approaches and criteria used to support decision-making in FWV are also collected and analyzed. Building upon these findings, an hourglass model is synthesized to provide a holistic illustration of decision-making in FWV. This study untangles the complexities of FWV decision-making and sheds light on the limitations of current studies. We anticipate this study will make more people realize that FWV is a multidisciplinary issue and requires the collective participation of researchers, practitioners, policymakers, and consumers. Such collective engagement is essential to effectively address practical challenges and propel the transition of the current food system toward a more resource-efficient paradigm.
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Tomada de Decisões , Alimentos , Gerenciamento de Resíduos/métodos , Perda e Desperdício de AlimentosRESUMO
PURPOSE: Although studies have suggested that gut microbiota may be associated with intervertebral disk disease, their causal relationship is unclear. This study aimed to investigate the causal relationship between the gut microbiota and its metabolic pathways with the risk of intervertebral disk degeneration (IVDD), low back pain (LBP), and sciatica. METHODS: Genetic variation data for 211 gut microbiota taxa at the phylum to genus level were obtained from the MiBioGen consortium. Genetic variation data for 105 taxa at the species level and 205 metabolic pathways were obtained from the Dutch Microbiome Project. Genetic variation data for disease outcomes were obtained from the FinnGen consortium. The causal relationships between the gut microbiota and its metabolic pathways and the risk of IVDD, LBP, and sciatica were evaluated via Mendelian randomization (MR). The robustness of the results was assessed through sensitivity analysis. RESULTS: Inverse variance weighting identified 46 taxa and 33 metabolic pathways that were causally related to IVDD, LBP, and sciatica. After correction by weighted median and MR-PRESSO, 15 taxa and nine pathways remained stable. After FDR correction, only the effect of the genus_Eubacterium coprostanoligenes group on IVDD remained stable. Sensitivity analyses showed no evidence of horizontal pleiotropy, heterogeneity, or reverse causation. CONCLUSION: Some microbial taxa and their metabolic pathways are causally related to IVDD, LBP, and sciatica and may serve as potential intervention targets. This study provides new insights into the mechanisms of gut microbiota-mediated development of intervertebral disk disease.
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Microbioma Gastrointestinal , Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Dor Lombar , Ciática , Humanos , Ciática/epidemiologia , Ciática/genética , Degeneração do Disco Intervertebral/epidemiologia , Degeneração do Disco Intervertebral/genética , Dor Lombar/epidemiologia , Dor Lombar/genética , Microbioma Gastrointestinal/genética , Análise da Randomização Mendeliana , Estudo de Associação Genômica AmplaRESUMO
Miniature robots have been widely studied and applied in the fields of search and rescue, reconnaissance, micromanipulation, and even the interior of the human body benefiting from their highlight features of small size, light weight, and agile movement. With the development of new smart materials, many functional actuating elements have been proposed to construct miniature robots. Compared with other actuating elements, piezoelectric actuating elements have the advantages of compact structure, high power density, fast response, high resolution, and no electromagnetic interference, which make them greatly suitable for actuating miniature robots, and capture the attentions and favor of numerous scholars. In this paper, a comprehensive review of recent developments in miniature piezoelectric robots (MPRs) is provided. The MPRs are classified and summarized in detail from three aspects of operating environment, structure of piezoelectric actuating element, and working principle. In addition, new manufacturing methods and piezoelectric materials in MPRs, as well as the application situations, are sorted out and outlined. Finally, the challenges and future trends of MPRs are evaluated and discussed. It is hoped that this review will be of great assistance for determining appropriate designs and guiding future developments of MPRs, and provide a destination board to the researchers interested in MPRs.
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OBJECTIVE: To investigate the bioactive compounds of Schisandrae Chinensis Fructus (SCF) and their mechanisms of action in the treatment of drug-induced liver injury (DILI), specifically Acetaminophen (APAP)-induced DILI. METHOD: Chemical components in SCF were identified using the UPLC-Q-TOF-MS method. Active components were then screened using HotMap, combined with SCF efficacy results concerning the prevention and treatment of drug-induced liver injury. Its direct target was elucidated using a comprehensive chemical-pharmacodynamic-exosome approach. RESULT: We identified Schisandrol A, is a lignan component, as a key active compound that improved the symptoms DILI in mouse liver tissue; specifically, reducing oxidative stress and thereby the inflammatory response. To further understand the biological function of miRNAs in mouse liver exosomes, we used TargetScan (v5.0) and Miranda (v3.3a) to predict the target genes of MicroRNAs (miRNAs), where changes in the expression of mmu-let-7 family miRNAs were closely related to autophagy. This revealed differential miRNA target genes that were involved in 20 Kyoto Encyclopedia of Genes and Genomes pathways, including glycerol phosphate metabolism, inositol phosphate metabolism, phospholipase D signaling pathway, Rap1 signaling pathway, and Ras signaling pathway. CONCLUSION: Schisandrol A alleviated the symptoms of DILI in mice by inhibiting oxidative stress and inflammation, whereas, it alleviated DILI by activating autophagy in the exosomes.
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Piezoelectric ultrasonic-assisted precision machining (PUAPM) technology is considered to be an efficient and environmentally friendly machining strategy by virtue of cutting force reduction, ductile cutting promotion, tool wear and machining noise reduction. Piezoelectric ultrasonic transducer (PUT) provides ultrasonic energy for PUAPM system, which is the core component to ensure the normal operation of the system. PUTs for PUAPM devices have emerged endlessly in recent decades and have been successfully applied in many fields, such as MEMS, biomedicine, optoelectronics, aerospace, etc. However, there is no comprehensive classification and analysis of the basic configurations, excitation principles, typical structures, performance analyses and control strategies for PUT. This work gives a critical review of research on PUT in recent years, especially the structural optimization, application expansion and ultrasonic energy stabilization in PUAPM. The influence mechanism of excitation mode, modal type, modal combination, horn structure and ceramic arrangement on the optimization of PUT structure is summarized. The improvement effect and mechanism of PUT vibration dimension, amplitude, frequency and structural characteristics on surface roughness, surface texture and cutting force are discussed. In addition, the causes of PUT amplitude fluctuation, and the influence of sensing and control methods on PUT amplitude regulation and system integration are analyzed. This review will help in understanding the current development and diversified applications of PUT and will promote the application of ultrasonic technology in more fields.
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Soil organic carbon (SOC) is essential for most soil functions. Changes in land use from natural land to cropland disrupt long-established SOC balances and reduce SOC levels. The intensive use of chemical fertilisers in modern agriculture accelerates the rate of SOC depletion. Domestic organic residues (DOR) are a valuable source of SOC replenishment with high carbon content. However, there is still a lack of knowledge and data regarding whether and to what extent DOR can contribute to replenishing SOC. This paper aims to unpack the potential of DOR as a SOC source. Total SOC demand and annual SOC loss are defined and calculated. The carbon flow within different DOR management systems is investigated in three countries (China, Australia, and The Netherlands). The results show that the total SOC demand is too large to be fulfilled by DOR in a short time. However, DOR still has a high potential as a source of SOC as it can mitigate the annual SOC loss by up to 100%. Achieving this 100% mitigation requires a shift to more circular management of DOR, in particular, more composting, and direct land application instead of landfilling and incineration (Australia and China), or a higher rate of source separation of DOR (The Netherlands). These findings form the basis for future research on DOR recycling as a SOC source.
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Solo , Gerenciamento de Resíduos , Solo/química , Carbono/análise , Países Baixos , Agricultura/métodos , China , AustráliaRESUMO
Extensive agricultural activities have been shown to degrade soils, promoting research into improving soil quality. One such method is to increase the amount of organic matter in the soil, and domestic organic residues (DOR) are commonly used for this purpose. The environmental impact of DOR-derived products, from production to agricultural application, remains unclear in current research. With the aim to have a more comprehensive understanding of the challenges and opportunities in DOR management and reuse, this study extended the boundaries of Life Cycle Assessment (LCA) to include the transport, treatment, and application of treated DOR on a national level while also quantifying soil carbon sequestration that has been less addressed in relevant LCA studies. This study focuses on The Netherlands, where incineration predominates, as a representative case to explore the benefits and trade-offs of moving towards more biotreatment for DOR. Two main biotreatments were considered, composting and anaerobic digestion. The results indicate that biotreatment of kitchen and yard residues generally has higher environmental impacts than incineration, including increased global warming and fine particulate matter formation. However, biotreatment of sewage sludge has lower environmental impacts than incineration. Substitution of nitrogen and phosphorus fertilisers with compost reduces mineral and fossil resource scarcity. In fossil-based energy systems like The Netherlands, replacing incineration with anaerobic digestion yields the highest benefit for fossil resource scarcity (61.93 %) due to energy recovery from biogas and the predominant use of fossil resources in the Dutch energy system. These findings indicate that replacing incineration with biotreatment of DOR may not benefit all impact categories in LCA. The environmental performance of substituted products can significantly influence the environmental benefits of increased biotreatment. Future studies or implementation of increased biotreatment should consider trade-offs and local context.
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Meio Ambiente , Solo , Animais , Agricultura/métodos , Incineração , Esgotos , Estágios do Ciclo de VidaRESUMO
This study explored whether the risk of thyroid cancer in Asian women is associated with consumption of oral contraceptives (Diane-35). We conducted a population-based, retrospective cohort study using the Taiwan National Health Insurance Research Database. From the database, 9865 women aged 18 to 65 years who were prescribed Diane-35 between 2000 and 2012 were included in the Diane-35 group, and 39,460 women who were not prescribed Diane-35 were included in the comparison group and were frequency-matched by age and index year. Both groups were followed until 2013 to calculate the incidence of thyroid cancer. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox proportional hazard model. The median (standard deviation) follow-up duration was 7.08 (3.63) and 7.04 (3.64) years in the Diane-35 and the comparison group, respectively. The incidence of thyroid cancer was 1.80-fold higher in the Diane-35 group than in the comparison group (2.72 vs 1.51 per 10,000 person-years). The cumulative incidence of thyroid cancer was significantly higher in the Diane-35 group than in the comparison group (log-rank test, P = .03). An elevated hazard ratio of thyroid cancer was observed in the Diane-35 group than in the comparison group (HR: 1.91, 95% CI: 1.10-3.30). In subgroup analysis, patients aged 30 to 39 years showed a higher hazard ratio of developing thyroid cancer after consuming Diane-35 than those in the comparison group (HR: 5.58, 95% CI: 1.84-16.91). The study provides evidence that women aged 30 to 39 years consuming Diane-35 are at increased risk of thyroid cancer. Nevertheless, a larger population with a longer follow-up may be necessary to confirm causality.
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Acetato de Ciproterona , Neoplasias da Glândula Tireoide , Humanos , Feminino , Acetato de Ciproterona/efeitos adversos , Anticoncepcionais Orais/efeitos adversos , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/induzido quimicamente , Neoplasias da Glândula Tireoide/epidemiologia , Taiwan/epidemiologia , IncidênciaRESUMO
BACKGROUND: This paper evaluated the clinical utility of massively parallel sequencing-based non-invasive prenatal testing (NIPT) for detecting trisomy 21 (T21), T18, T13, sex chromosome aneuploidies (SCA), and rare chromosome aneuploidies (RCA) among the data collected by a clinical laboratory in southern China. METHODS: In a 3-year period between January 2017 and December 2019, over 40,000 pregnant women underwent NIPT clinical screening test for fetal T21, T18, T13, SCA, and RCA in our laboratory. NIPT samples were processed using the NextSeq CN500 platform. The positive results were confirmed by karyotyping, and chromosomal microarray analysis (CMA) or copy number variants (CNV) sequencing. Details of the pregnancy outcomes were collected via telephone interview. RESULTS: NIPT results were available for 41,819 cases; 691 positive cases were reported. The overall sensitivity for detection of T21, T18, T13, SCA, and RCA was 99.21, 100.00, 100.00, 98.55, and 100.00%, and the specificity was 99.95, 99.94, 99.98, 99.69, and 99.92%, respectively. The positive predictive values (PPVs) for detection of T21, T18, T13, SCA, and RCA were 85.62, 45.24, 40.00, 34.17, and 13.51%, respectively, and those for detection of 45,X, 47,XXY, 47,XXX, 47,XYY, and 46,XY(delX) 20.00, 59.18, 28.95, 61.54, and 25.00%, respectively. Regarding pregnancy outcomes, 92.38% of the pregnancies with confirmed aneuploidies were terminated, and 91.20% of those identified as having a false-positive result were carried to term. Among 252 unconfirmed cases, 24.60% of the pregnancies were terminated and 38.10% carried to term, while 37.30% declined interview. CONCLUSIONS: NIPT is widely used to screen fetal aneuploidies based on its high sensitivity and specificity. However, in this study, the PPVs of NIPT in terms of detecting T18, T13, XO, XXX and RCA were < 50%. In addition, more than one-third of NIPT-positive women did not accept invasive prenatal diagnosis. Confirmatory diagnosis is strongly recommended for women with positive NIPT outcomes before any further decision is made.
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Síndrome de Down , Gestantes , Feminino , Gravidez , Humanos , Laboratórios Clínicos , Diagnóstico Pré-Natal/métodos , Síndrome de Down/diagnóstico , Aneuploidia , Resultado da GravidezRESUMO
Multiple degrees of freedom (DOFs) motion manipulation of various objects is a crucial skill for robotic systems, which relies on various robotic hands. However, traditional robotic hands suffer from problems of low manipulation accuracy, poor electromagnetic compatibility and complex system due to limitations in structures, principles and transmissions. Here we present a direct-drive rigid piezo robotic hand (PRH) constructed on functional piezoelectric ceramic. Our PRH holds four piezo fingers and twelve motion DOFs. It achieves high adaptability motion manipulation of ten objects employing pre-planned functionalized hand gestures, manipulating plates to achieve 2L (linear) and 1R (rotary) motions, cylindrical objects to generate 1L and 1R motions and spherical objects to produce 3R motions. It holds promising prospects in constructing multi-DOF ultra-precision manipulation devices, and an integrated system of our PRH is developed to implement several applications. This work provides a new direction to develop robotic hand for multi-DOF motion manipulation from micro scale to macro scale.
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Sulfide detection in domestic wastewater is widely demanded, as sulfide induces odour nuisance and wastewater assets corrosion. However, traditional sulfide detection methods are usually plagued by the limited detection range or interference from impurities. To address these constraints, this study improved the ion chromatographic pulsed amperometric method (IC-PAD) and tested its validity for use in domestic wastewater. Prior to sulfide detection, sulfide-containing sample collection usually requires the use of sulfide antioxidant buffers (SAOB) to minimize sulfide loss. Different sample matrixes require different SAOB recipes, which increases complexity and uncertainty when measuring different environmental samples. Therefore, this study also developed a more convenient and generic sample collection method without the addition of SAOB. The results indicated that the proposed SAOB-free sample collection method could minimize the sulfide loss during sample collection. The IC-PAD method showed a wide linear detection range up to 10 mg-S/L. The detection limit was 3 µg-S/L. Matrix effect studies showed that 1 g/L glucose, formate, acetate, methanol, ethanol, propionate, butyrate, lactate, or sulfate had no evident interference on sulfide measurement. However, 5 mM phosphate buffer led to interference, but reducing the KOH eluent concentration from 62 to 30 mM avoid this interference. Wolfe's vitamin mixture and Wolfe's modified mineral mixture could cause diminutive interference equivalent to 2.53 ± 1.32 µg-S/L sulfide. Moreover, the interference caused by chloride indicated that the IC-PAD method is more applicable for measuring sulfide in low-chloride wastewater. To this end, the IC-PAD method showed high accuracy and precision in the real domestic wastewater samples with chloride concentration of 68 mg/L. The recovery was higher than 97% and the relative standard deviation (RSD) was lower than 1.2%. This study demonstrated the potential use of IC-PAD method for measuring sulfide in real domestic wastewater and possible interference from the solution matrix to be considered.
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Cloretos , Águas Residuárias , Cloretos/análise , Cromatografia , Sulfetos/química , Glucose , AntioxidantesRESUMO
BACKGROUND: Percutaneous kyphoplasty (PKP) or percutaneous vertebroplasty (PVP) are commonly employed for Kummell's disease in stages II-III; however, these techniques produce some complications. OBJECTIVE: To compare the clinical efficacy and imaging results of percutaneous vertebroplasty + bone cement-augmented short-segment pedicle screw fixation (PSPVP) versus transpedicular intracorporeal bone grafting + pedicle screw fixation (PSIBG) in the treatment of stage II-III Kummell's disease. METHODS: A total of 69 patients admitted between November 2017 and March 2021 were included in this study; 36 of these were treated with PSPVP, and 33 were treated with PSIBG. Patients in the two groups were compared in terms of perioperative, follow-up, and imaging data. RESULTS: No statistically significant differences were found between the two groups in terms of operation duration (P > 0.05). However, the PSPVP group was superior to the PSIBG group in terms of incision length, intraoperative blood loss, and length of stay (P < 0.05). All patients were followed up for more than 12 months. The VAS score, height of anterior vertebral margin, kyphosis Cobb angle, wedge angle of the affected vertebra at seven days after surgery and last follow-up, and the ODI index at the last follow-up of the two groups were significantly improved compared with figures before surgery (P < 0.05). Compared with values before surgery, no statistically significant differences were found in the height of the posterior vertebral margin in the PSPVP group at seven days after surgery and at the last follow-up (P > 0.05). There were also no statistically significant differences in the VAS score, ODI index, kyphosis Cobb angle, and wedge angle of the affected vertebra between the two groups at corresponding time points (P > 0.05). The heights of the anterior and posterior vertebral margins in the PSIBG group were better than those in the PSPVP group after surgery and at the last follow-up (P < 0.05). In the PSPVP group, a pedicle screw fracture occurred in one patient two months after surgery, while an upper adjacent vertebral fracture occurred in one patient eight months after surgery. CONCLUSION: Both PSPVP and PSIBG can achieve good early clinical efficacy in the treatment of stage II-III Kummell's disease, with PSPVP being relatively less invasive while producing a poorer orthopedic effect and more complications than PSIBG.
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Cifose , Parafusos Pediculares , Fraturas da Coluna Vertebral , Vertebroplastia , Humanos , Vertebroplastia/efeitos adversos , Vertebroplastia/métodos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Fraturas da Coluna Vertebral/complicações , Resultado do Tratamento , Cifose/tratamento farmacológico , Cifose/etiologia , Cifose/cirurgia , Fixação Interna de Fraturas/métodos , Parafusos Pediculares/efeitos adversos , Estudos Retrospectivos , Cimentos Ósseos/uso terapêutico , Vértebras LombaresRESUMO
Airborne particulates (PM2.5 and TSP) were collected from outdoor and indoor areas at urban (Haizhu District) and suburban (Huadu District) sites from 2019 to 2020 in Guangzhou. Three nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) in the airborne particulates were identified by a gas chromatograph equipped with a triple-quadrupole mass spectrometer. In the Haizhu District and Huadu District, the nitro-PAH concentrations in PM2.5 and TSP did not show a significant decrease from winter to summer. From 2019 to 2020, the difference in the average concentration of nitro-PAHs in PM2.5 and TSP in Guangzhou was relatively low and had no statistical significance. The diagnostic ratios of 2-nitrofluorene (2-NF)/1-nitropyrene (1-NP) in TSP are less than five, while for 2-NF/1-NP in outdoor PM2.5 in the summer of 2019 and 2020 are more than five, which indicates that nitro-PAHs in the atmospheric PM2.5 in Guangzhou during summer mainly originated from the secondary formation of atmospheric photochemical reactions between parent PAHs and oxidants (·OH, NO3, and O3). 9-Nitroanthracene (9-NT) made the most significant contribution to the total nitro-PAH concentration. The incremental lifetime cancer risks (ILCRs) of nitro-PAHs in PM2.5 and TSP by inhalation exposure indicated low potential health risks in the urban-suburban of Guangzhou.
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Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Hidrocarbonetos Policíclicos Aromáticos/análise , Material Particulado/análise , Poluentes Atmosféricos/análise , Nitratos , Carvão Mineral/análise , Medição de Risco , Estações do Ano , China , Monitoramento AmbientalRESUMO
Methane emissions from the sewer system are considered to be a non-negligible source of aggravating the greenhouse effect. Meanwhile, the sewer system has long been plagued by sulfide-induced corrosion problems. This study explored the possibility of using a bioelectrochemical system to intensify the competition between electroactive bacteria, methanogens and sulfate-reducing bacteria, thereby reducing the production of methane and sulfide. Dual-chamber bioelectrochemical reactors were constructed and operated in fed-batch mode with the coexistence of Electroactive bacteria, Methanogenic archaea and Sulfate-reducing bacteria. Acetate was supplied as the sole carbon source. The results indicated that electrogenesis induced by the anode potentials of -0.42 V and -0.2 V (vs. Ag/AgCl) had advantages over methanogenesis and sulfidogenesis in consuming acetate. The stimulated electrogenesis by anode potentials resulted in a decrease in pH. Methane production was suppressed in the reactors with anode potentials of -0.42 and -0.2 V compared to open circuit controls. In contrast to methane, the capacity for sulfide production was facilitated in the reactors with the anode potentials of -0.42 V and -0.2 V compared to open circuit controls. 16s rRNA gene analysis showed that Geobacter was the most abundant genus on the anode biofilm in the anode potential-controlled reactor, while acetoclastic methanogens dominated in open circuit controls. Methanosaeta and Methanosarcina were the most abundant methanogens in open circuit controls. Collectively, our study demonstrates that the use of electrodes with anode potential control can help to control methane emissions, but could not yet prevent sulfide production, which requires further research.
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Bactérias , Metano , RNA Ribossômico 16S/genética , Eletrodos , Bactérias/genética , Acetatos , Sulfatos , SulfetosRESUMO
Objective: After laminoplasty, the cervical sagittal curvature of some patients tend to be lordotic, this phenomenon cannot be explained by the theory of laminoplasty, and the reason remains unknown. We explored the possible role played by pinching cervical spondylotic myelopathy (PCSM) in the cervical sagittal curvature change in patients after laminoplasty. Methods: From April 2017 to May 2019, we studied 122 patients undergoing laminoplasty with cervical spondylotic myelopathy (CSM). All patients were divided into Group A (anterior compression only, without PCSM) and Group B (both anterior and posterior compression, with PCSM). The visual analogue scale (VAS) was used to measure pain, and modiï¬ed Japanese Orthopedic Association (mJOA) score was derived. The cervical global angle (CGA) and the range of cervical motion (ROM) were compared. The clinical and imaging results were compared between Group A and Group B. Results: After laminoplasty, both the mean VAS and mJOA scores improved significantly in Group A and Group B, the mJOA recovery rate of Group B was better than that of Group A (P < 0.05). The mean CGA and ROM decreased in Group A, but increased in Group B. MRI revealed that the ligamentum flavum of Group A was significantly thinner than that of Group B (P < 0.05). Conclusions: Because of the hypertrophic and folded ligamentum flavum compressing the dorsal spinal cord, patients with PCSM may maintain a compulsive kyphotic posture. After laminoplasty, the cervical sagittal curvature of these patients tend to be lordotic due to the release of dorsal spinal cord compression.
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Amphibious robots can undertake various tasks in terrestrial and aquatic environments for their superior environmental compatibility. However, the existing amphibious robots usually utilize multi-locomotion systems with transmission mechanisms, leading to complex and bulky structures. Here, a miniature amphibious robot based on vibration-driven locomotion mechanism is developed. The robot has two unique rigid-flexible hybrid modules (RFH-modules), in which a soft foot and a flexible fin are arranged on a rigid leg to conduct vibrations from an eccentric motor to the environment. Then, it can run on ground with the soft foot adopting the friction locomotion mechanism and swim on water with the flexible fin utilizing the vibration-induced flow mechanism. The robot is untethered with a compact size of 75 × 95 × 21 mm3 and a small weight of 35 g owing to no transmission mechanism or joints. It realizes the maximum speed of 815 mm s-1 on ground and 171 mm s-1 on water. The robot, actuated by the RFH-modules based on vibration-driven locomotion mechanism, exhibits the merits of miniature structure and fast movements, indicating its great potential for applications in narrow amphibious environments.
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Robótica , Locomoção , Natação , Vibração , ÁguaRESUMO
The volume of waste produced by aspects of both industrial life and daily life has increased in the past few years in conjunction with the rapidly growing economy in China. In urban areas, citizens consume more resources and produce much waste, which pollutes the environment. Many cities have proposed numerous regulations for waste separation to help build environmentally friendly cities. Plenty of studies tried to reveal the mechanism of residents' waste separation behavior in different theoretical perspectives but were unable to clarify the effect of waste separation factors in university. Moreover, the response and performance of undergraduate students after the waste separation regulations are proposed and are not well discussed. To clarify the mechanism of waste separation behavior in campus and evaluate the response and performance, in this study, a questionnaire is used to sample undergraduate students from the Higher Education Mega Center in Guangzhou. With the use of SPSS 23.0, this study conducts an empirical analysis; the results of which show that (1) environmental awareness and personal responsibility have a significant positive impact on behavior attitude; (2) convenience and economic cost have a significant positive impact on perceived behavior control; (3) intention has a partial mediating role between behavior attitude, subjective norms, and perceived behavior control; and (4) habits directly affect behavior and regulate the relationship between intention and behavior. The results will provide some meaningful implications for the government.