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1.
Proc Natl Acad Sci U S A ; 119(34): e2207767119, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35969749

RESUMO

Untethered soft miniature robots capable of accessing hard-to-reach regions can enable new, disruptive, and minimally invasive medical procedures. However, once the control input is removed, these robots easily move from their target location because of the dynamic motion of body tissues or fluids, thereby restricting their use in many long-term medical applications. To overcome this, we propose a wireless spring-preloaded barbed needle release mechanism, which can provide up to 1.6 N of force to drive a barbed needle into soft tissues to allow robust on-demand anchoring on three-dimensional (3D) surfaces. The mechanism is wirelessly triggered using radio-frequency remote heating and can be easily integrated into existing untethered soft robotic platforms without sacrificing their mobility. Design guidelines aimed at maximizing anchoring over the range of the most biological tissues (kPa range) and extending the operating depth of the device inside the body (up to 75%) are also presented. Enabled by these advances, we achieve robust anchoring on a variety of ex vivo tissues and demonstrate the usage of such a device when integrated with existing soft robotic platforms and medical imaging. Moreover, by simply changing the needle, we demonstrate additional functionalities such as controlled detachment and subsurface drug delivery into 3D cancer spheroids. Given these capabilities, our proposed mechanism could enable the development of a new class of biomedical-related functionalities, such as local drug delivery, disease monitoring, and hyperthermia for future untethered soft medical robots.


Assuntos
Robótica , Sistemas de Liberação de Medicamentos , Movimento (Física) , Robótica/métodos
2.
Nature ; 554(7690): 81-85, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29364873

RESUMO

Untethered small-scale (from several millimetres down to a few micrometres in all dimensions) robots that can non-invasively access confined, enclosed spaces may enable applications in microfactories such as the construction of tissue scaffolds by robotic assembly, in bioengineering such as single-cell manipulation and biosensing, and in healthcare such as targeted drug delivery and minimally invasive surgery. Existing small-scale robots, however, have very limited mobility because they are unable to negotiate obstacles and changes in texture or material in unstructured environments. Of these small-scale robots, soft robots have greater potential to realize high mobility via multimodal locomotion, because such machines have higher degrees of freedom than their rigid counterparts. Here we demonstrate magneto-elastic soft millimetre-scale robots that can swim inside and on the surface of liquids, climb liquid menisci, roll and walk on solid surfaces, jump over obstacles, and crawl within narrow tunnels. These robots can transit reversibly between different liquid and solid terrains, as well as switch between locomotive modes. They can additionally execute pick-and-place and cargo-release tasks. We also present theoretical models to explain how the robots move. Like the large-scale robots that can be used to study locomotion, these soft small-scale robots could be used to study soft-bodied locomotion produced by small organisms.


Assuntos
Biomimética/métodos , Desenho de Equipamento , Locomoção , Robótica/instrumentação , Elasticidade , Rotação , Natação , Caminhada
3.
BMC Public Health ; 24(1): 425, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336690

RESUMO

OBJECTIVE: To translate the Stressors in Breast Cancer Scale (SBCS) from English to Chinese and assess its psychometric properties. METHODS: The Brislin's translation model was applied to perform forward translation, back translation, cross-cultural adaptation, Whereas the Chinese version of the SBCS was formed by conducting pre-testing. A cohort of 878 breast cancer patients participated in this methodological study. Content validity, construct validity, convergent validity, discriminant validity, and criterion-related validity were used to establish validity. Internal consistency reliability, split-half reliability, and test-retest reliability were used to establish reliability. RESULTS: The final scale contained five dimensions and 24 items, including interpersonal relationship and healthcare strains, worries and concerns about the future, physical appearance and sex strains, daily difficulties and health. The average content validity index of the scale was 0.975. The goodness-of-fit index (χ2/DF = 2.416, RMSEA = 0.057, GFI = 0.896, CFI = 0.947, IFI = 0.947, and TLI = 0.939) indicated that the model was well-fitted. The composite reliability (CR) of the dimensions ranged from 0.825 to 0.934, the average variance extracted (AVE) ranged from 0.539 to 0.712, and the correlation coefficients of each dimension with the other dimensions were less than the square root of the AVE for that dimension. The Criterion-related validity was 0.511. The Cronbach's alpha was 0.938, and the dimensions ranged from 0.779 to 0.900. Split-half reliability was 0.853, with dimensions ranging from 0.761 to 0.892. Test-retest reliability was 0.855. CONCLUSIONS: The Chinese version of the SBCS has good reliability and validity, which can be applied to the assessment of stressors in breast cancer patients in China.


Assuntos
Povo Asiático , Neoplasias da Mama , Psicometria , Feminino , Humanos , Povo Asiático/psicologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/psicologia , China , Reprodutibilidade dos Testes , Inquéritos e Questionários , Tradução , Estresse Psicológico/diagnóstico
4.
Molecules ; 29(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38930847

RESUMO

Electrochemical nitrate reduction (NO3-RR) has been recognized as a promising strategy for sustainable ammonia (NH3) production due to its environmental friendliness and economical nature. However, the NO3-RR reaction involves an eight-electron coupled proton transfer process with many by-products and low Faraday efficiency. In this work, a molybdenum oxide (MoOx)-decorated titanium dioxide nanotube on Ti foil (Mo/TiO2) was prepared by means of an electrodeposition and calcination process. The structure of MoOx can be controlled by regulating the concentration of molybdate during the electrodeposition process, which can further influence the electron transfer from Ti to Mo atoms, and enhance the binding energy of intermediate species in NO3-RR. The optimized Mo/TiO2-M with more Mo(IV) sites exhibited a better activity for NO3-RR. The Mo/TiO2-M electrode delivered a NH3 yield of 5.18 mg h-1 cm-2 at -1.7 V vs. Ag/AgCl, and exhibited a Faraday efficiency of 88.05% at -1.4 V vs. Ag/AgCl. In addition, the cycling test demonstrated that the Mo/TiO2-M electrode possessed a good stability. This work not only provides an attractive electrode material, but also offers new insights into the rational design of catalysts for NO3-RR.

5.
Arch Orthop Trauma Surg ; 144(2): 583-589, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37898976

RESUMO

PURPOSE: This study was designed to investigate influencing factors of out-of-hospital anticoagulation therapy compliance among patients undergoing major orthopaedic surgeries. METHODS: A cross-sectional, descriptive study was conducted from July 2022 to February 2023 among outpatients who underwent major orthopedic surgery in our hospital. Patients (n = 200) were surveyed using the General Information Questionnaire, the General Self-Efficacy Scale, the Specificity of Medication-Taking Beliefs Scale, and the Morisky Medication Adherence Scale. Factors that influenced patient compliance were also determined using univariate and multivariate regression analyses. RESULTS: One hundred eighty-three valid questionnaires were returned, the compliance with outpatient anticoagulation therapy among patients undergoing major orthopaedic surgeries was good in 56.3% (103/183) of all cases and poor in 43.7% (80/183). Multivariate logistic regression analysis showed that medication duration, adverse effects, self-efficacy and medication beliefs influenced adherence to out-of-hospital anticoagulation therapy in patients undergoing major orthopedic surgery (P < 0.05). CONCLUSIONS: Poor compliance with out-of-hospital anticoagulation therapy in patients undergoing major orthopedic surgery is mainly associated with a long course of medication, adverse reactions, low self-efficacy and low medication beliefs. Healthcare staff should strengthen post-discharge anticoagulation management based on relevant influencing factors to enhance patient compliance.


Assuntos
Procedimentos Ortopédicos , Pacientes Ambulatoriais , Humanos , Adesão à Medicação , Estudos Transversais , Assistência ao Convalescente , Alta do Paciente , Anticoagulantes/uso terapêutico
6.
Angew Chem Int Ed Engl ; 62(32): e202303290, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37132602

RESUMO

Cluster catalysts are attractive for their atomically precise structures, defined compositions, tunable coordination environments, uniform active sites, and their ability to transfer multiple electrons, but they suffer from poor stability and recyclability. Here, we report a general approach to the direct insolubilization of a water soluble polyoxometalate (POM) [{(B-α-PW9 O34 )Co3 (OH)(H2 O)2 (O3 PC(O)-(C3 H6 NH3 )PO3 )}2 Co]14- (Co7 ) and formation of a series of POM-based solid catalysts with the counter-cations Ag+ , Cs+ , Sr2+ , Ba2+ , Pb2+ , Y3+ , and Ce3+ . They exhibit improved catalytic activities for visible-light-driven water oxidation following the trend CsCo7 >SrCo7 >AgCo7 >CeIII Co7 >BaCo7 >YCo7 >PbCo7 . While CsCo7 exhibits mainly homogeneous catalysis, the others are predominantly heterogeneous catalysts. An optimal oxygen yield of 41.3 % and a high apparent quantum yield (AQY) of 30.6 % for SrCo7 is obtained, which is comparable to that of the parent homogeneous POM. Band gap structures, UV/Vis spectra, and real-time laser flash photolysis experiments collectively suggest that easier electron transfer from the solid POM catalyst to the photosensitizer promotes photocatalytic water oxidation performance. These solid POM catalysts exhibit good stability, which is directly confirmed by a combination of Fourier-transform infrared spectroscopy, electron microscopy, X-ray diffraction patterns, Raman spectroscopy, X-ray photoelectron spectroscopy, five cycles of tests, and poisoning experiments.

7.
J Chem Phys ; 156(20): 204301, 2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35649828

RESUMO

The adsorption and self-assembly structures of melamine molecules on an Ag(111) surface are studied by low temperature scanning tunneling microscopy (STM) combined with tip-enhanced Raman spectroscopy (TERS). Two ordered self-assembly phases of melamine molecules on Ag(111) were studied by STM and TERS, combining with first-principles simulations. The α-phase consists of flat-lying melamine molecules, while the ß-phase consists of mixed up-standing/tilted melamine molecules. Moreover, dehydrogenation of melamine can be controlled by annealing the sample as well as by a tip-enhanced photo-catalytic effect. Our work demonstrates TERS as a powerful tool not only for investigating the configuration and vibration properties of molecules on a metal surface with high spatial resolution but also for manipulating the chemical reactions with tip and photo-induced effects.

8.
BMC Plant Biol ; 21(1): 371, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34384382

RESUMO

BACKGROUND: The Orchid family is the largest families of the monocotyledons and an economically important ornamental plant worldwide. Given the pivotal role of this plant to humans, botanical researchers and breeding communities should have access to valuable genomic and transcriptomic information of this plant. Previously, we established OrchidBase, which contains expressed sequence tags (ESTs) from different tissues and developmental stages of Phalaenopsis as well as biotic and abiotic stress-treated Phalaenopsis. The database includes floral transcriptomic sequences from 10 orchid species across all the five subfamilies of Orchidaceae. DESCRIPTION: Recently, the whole-genome sequences of Apostasia shenzhenica, Dendrobium catenatum, and Phalaenopsis equestris were de novo assembled and analyzed. These datasets were used to develop OrchidBase 4.0, including genomic and transcriptomic data for these three orchid species. OrchidBase 4.0 offers information for gene annotation, gene expression with fragments per kilobase of transcript per millions mapped reads (FPKM), KEGG pathways and BLAST search. In addition, assembled genome sequences and location of genes and miRNAs could be visualized by the genome browser. The online resources in OrchidBase 4.0 can be accessed by browsing or using BLAST. Users can also download the assembled scaffold sequences and the predicted gene and protein sequences of these three orchid species. CONCLUSIONS: OrchidBase 4.0 is the first database that contain the whole-genome sequences and annotations of multiple orchid species. OrchidBase 4.0 is available at http://orchidbase.itps.ncku.edu.tw/.


Assuntos
Bases de Dados Genéticas , Orchidaceae/genética , Genoma de Planta
9.
BMC Infect Dis ; 19(1): 969, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31718560

RESUMO

BACKGROUND: Hand, foot and mouth disease (HFMD) is a serious infectious disease, which has become a public health problem. Previous studies have shown that temperature may influence the incidence of HFMD, but most only focus on single city and the results are highly heterogeneous. Therefore, a multicity study was conducted to explore the association between temperature and HFMD in different cities and search for modifiers that influence the heterogeneity. METHODS: We collected daily cases of childhood HFMD (aged 0-5 years) and meteorological factors of 21 cities in Guangdong Province in the period of 2010-2013. Distributed lag non-linear model (DLNM) with quasi-Poisson was adopted to quantify the effects of temperature on HFMD in 21 cities. Then the effects of each city were pooled by multivariate meta-analysis to obtain the heterogeneity among 21 cities. Potential city-level factors were included in meta-regression to explore effect modifiers. RESULTS: A total of 1,048,574 childhood cases were included in this study. There was a great correlation between daily childhood HFMD cases and temperature in each city, which was non-linear and lagged. High heterogeneity was showed in the associations between temperature and HFMD in 21 cities. The pooled temperature-HFMD association was peaking at the 79th percentile of temperature with relative risk (RR) of 2.474(95% CI: 2.065-2.965) as compared to the median temperature. Latitude was the main modifier for reducing the heterogeneity to 69.28% revealed by meta-analysis. CONCLUSIONS: There was a strong non-linear and lagged correlation between temperature and HFMD. Latitude was strongly associated with the relationship between temperature and HFMD. Meanwhile, it had an effect on modifying the relationship. These findings can conducive to local governments developing corresponding preventive measures.


Assuntos
Doença de Mão, Pé e Boca/diagnóstico , Pré-Escolar , China/epidemiologia , Cidades , Doença de Mão, Pé e Boca/epidemiologia , Humanos , Incidência , Lactente , Recém-Nascido , Saúde Pública , Risco , Temperatura
10.
Environ Res ; 173: 262-269, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30928857

RESUMO

OBJECTIVE: Guangdong province is one of the provinces most frequently hit by tropical cyclones in China. Hand, foot and mouth disease (HFMD) continues to severely affect public health across the world. Our study aimed to evaluate the impacts of different grades of tropical cyclones and accompanying precipitation and wind velocity on HFMD among children younger than 6 years old in Guangdong province from 2009 to 2013. METHODS: A time-stratified case-crossover design was used to examine the association between tropical cyclones and childhood HFMD. Principal component analysis (PCA) was first used to eliminate multicollinearity among meteorological variables. Conditional Poisson regression was then applied to calculate odds ratios (ORs) and the 95% confidence intervals (CIs). RESULTS: Tropical storms increased the risk of HFMD among children below 6 years of age on lag 4 days (OR = 1.55, 95%CI: 1.28-1.88). Tropical storms were also a risk factor for boys below 3 years of age, boys between 3 and 6 and girls below 3 years of age with the largest OR = 1.52 (95%CI:1.15-2.00), OR = 1.81 (95%CI = 1.21-2.71) and OR = 1.51 (95%CI = 1.04-2.19), respectively. Precipitation during tropical cyclones had an adverse effect on childhood HFMD when reaching 25-49.9 mm or above 100 mm with OR = 1.20 (95%CI = 1.00-1.43) on lag 0 day and OR = 1.25 (95%CI = 1.04-1.49) on lag 7 days, respectively. For extreme wind velocity during tropical cyclones, the impact on childhood HFMD was largest on the day tropical cyclones landed (OR = 1.25, 95%CI: 1.06-1.48) with winds up to 13.9-24.4  m/s. CONCLUSIONS: Tropical storms can increase the risk of HFMD among children younger than 3 years old, especially boys between 3 and 6 years old. Precipitation during tropical cyclones is a risk factor for childhood HFMD when it is between 25 and 49.9 mm or above 100 mm. As extreme wind velocity reaches 13.9-24.4  m/s, it has an adverse effect on children's health. Children below 3 years old and boys between 3 and 6 should be given more consideration during tropical storms.


Assuntos
Tempestades Ciclônicas , Exposição Ambiental/estatística & dados numéricos , Doença de Mão, Pé e Boca/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Incidência , Lactente , Masculino , Razão de Chances , Temperatura , Vento
11.
Environ Res ; 169: 196-205, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30466013

RESUMO

OBJECTIVES: This study aims to estimate the impact of heatwaves from July 2010 to October 2012 on daily outpatient visits for respiratory disease (RD) in Cangnan, China and identify vulnerable populations. METHODS: The definition of heatwave was a period at least 3 consecutive days with maximum temperature exceeding 35 °C in this study. A time-stratified case-crossover design was conducted to examine the relationship between heatwaves and outpatient visits for RD. Patient data for the period from 2010 to 2012 were collected from the Third People's Hospital of Cangnan and daily meteorological data for the same period were collected from the China Meteorological Data Service Center. Data regarding the air pollution index (API), a composite indicator of air pollution, were collected from the Data Center of the Chinese Ministry of Environmental Protection. RD were identified based on the 10th revision International Classification of Diseases (ICD-10) codes (J00-J99). A conditional Poisson regression model was applied to examine the heatwave-RD association using the Relative Risk (RR) while adjusting for meteorological and air pollution factors including temperature, rainfall, wind speed, pressure, humidity, sunshine hours and API. RESULTS: During the study period, 4 heatwaves occurred and a total of 1732 outpatient visits for RD were reported. Heatwaves increased the frequency of RD outpatient visits and the highest RR of total RD was 1.155% and 95% Confidence Intervals (95% CI) was 1.084-1.232 at Lag 0. For subcategories, heatwaves increased the risk of infectious RD (Lag 0: RR =1.182, 95% CI: 1.106-1.263) and decreased the risk of non-infectious RD ((Lag 6: RR =0.750, 95% CI: 0.568-0.990). Moreover, heatwaves showed adverse effects on acute upper respiratory infection (Lag 0: RR =1.306, 95% CI: 1.177-1.450). The RR of outpatient visits for RD was statistically significant in females (Lag 0: RR =1.161, 95% CI: 1.046-1.298), males (Lag 4: RR =1.161, 95% CI: 1.096-1.261), young people aged 4-17 years (Lag 0: RR =1.741, 95% CI: 1.524-1.990) and elders aged 65 years or older (Lag 5: RR =1.412, 95% CI: 1.111-1.794) during heatwaves. CONCLUSIONS: Heatwaves had a significant harmful impact on daily outpatient visits for RD in Cangnan, especially for vulnerable population identified. These results can be used not only to strengthen the health education and protection of these vulnerable populations, but also to assist relevant organizations with developing intervention programmes and improving disease prevention and community care.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Temperatura Alta , Doenças Respiratórias/epidemiologia , Adolescente , Idoso , Poluição do Ar/estatística & dados numéricos , Criança , Pré-Escolar , China/epidemiologia , Estudos Cross-Over , Feminino , Humanos , Masculino , Pacientes Ambulatoriais , Tempo
12.
Proc Natl Acad Sci U S A ; 113(41): E6007-E6015, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27671658

RESUMO

Shape-programmable matter is a class of active materials whose geometry can be controlled to potentially achieve mechanical functionalities beyond those of traditional machines. Among these materials, magnetically actuated matter is particularly promising for achieving complex time-varying shapes at small scale (overall dimensions smaller than 1 cm). However, previous work can only program these materials for limited applications, as they rely solely on human intuition to approximate the required magnetization profile and actuating magnetic fields for their materials. Here, we propose a universal programming methodology that can automatically generate the required magnetization profile and actuating fields for soft matter to achieve new time-varying shapes. The universality of the proposed method can therefore inspire a vast number of miniature soft devices that are critical in robotics, smart engineering surfaces and materials, and biomedical devices. Our proposed method includes theoretical formulations, computational strategies, and fabrication procedures for programming magnetic soft matter. The presented theory and computational method are universal for programming 2D or 3D time-varying shapes, whereas the fabrication technique is generic only for creating planar beams. Based on the proposed programming method, we created a jellyfish-like robot, a spermatozoid-like undulating swimmer, and an artificial cilium that could mimic the complex beating patterns of its biological counterpart.

13.
Nano Lett ; 18(5): 2937-2942, 2018 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-29601201

RESUMO

The atomic structures of self-assembled silicon nanoribbons and magic clusters on Ag(110) substrate have been studied by high-resolution noncontact atomic force microscopy (nc-AFM) and tip-enhanced Raman spectroscopy (TERS). Pentagon-ring structures in Si nanoribbons and clusters have been directly visualized. Moreover, the vibrational fingerprints of individual Si nanoribbon and cluster retrieved by subnanometer resolution TERS confirm the pentagonal nature of both Si nanoribbons and clusters. This work demonstrates that Si pentagon can be an important element in building silicon nanostructures, which may find important applications for future nanoelectronic devices based on silicon.

14.
Med Care ; 56(5): 448-454, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29485529

RESUMO

OBJECTIVE: We sought to build on the template-matching methodology by incorporating longitudinal comorbidities and acute physiology to audit hospital quality. STUDY SETTING: Patients admitted for sepsis and pneumonia, congestive heart failure, hip fracture, and cancer between January 2010 and November 2011 at 18 Kaiser Permanente Northern California hospitals. STUDY DESIGN: We generated a representative template of 250 patients in 4 diagnosis groups. We then matched between 1 and 5 patients at each hospital to this template using varying levels of patient information. DATA COLLECTION: Data were collected retrospectively from inpatient and outpatient electronic records. PRINCIPAL FINDINGS: Matching on both present-on-admission comorbidity history and physiological data significantly reduced the variation across hospitals in patient severity of illness levels compared with matching on administrative data only. After adjustment for longitudinal comorbidity and acute physiology, hospital rankings on 30-day mortality and estimates of length of stay were statistically different from rankings based on administrative data. CONCLUSIONS: Template matching-based approaches to hospital quality assessment can be enhanced using more granular electronic medical record data.


Assuntos
Benchmarking/métodos , Pacientes Internados/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Indicadores de Qualidade em Assistência à Saúde , Índice de Gravidade de Doença , California , Comorbidade , Registros Eletrônicos de Saúde/normas , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Estudos Retrospectivos
15.
BMC Public Health ; 17(1): 641, 2017 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-28784172

RESUMO

BACKGROUND: Community engagement strategies are often integrated in public health interventions designed to promote condom use among men who have sex with men (MSM), a key population for HIV prevention. However, the ways in which condom use peer norms and self-efficacy play a role in the association between community engagement and condom use is unclear. This study examines the potential mediating roles of peer norms and self-efficacy in this association. METHODS: A nationwide cross-sectional online survey was conducted among Chinese MSM in 2015. Recruitment criteria included being born biologically male, being older than 16 years, having had anal sex with a man at least once during their lifetime, and having had condomless anal or vaginal sex in the past three months. Mplus 6.11 was used to conduct confirmatory factor analysis and path modeling analysis to examine the structural relationships between HIV/sexual health community engagement (e.g., joining social media and community events related to HIV and sexual health services), condom use peer norms, condom use self-efficacy, and frequency of condom use. RESULTS: The study found that HIV/sexual health community engagement, condom use peer norms, condom use self-efficacy, and frequency of condom use were mutually correlated. A good data model was achieved with fit index: CFI = 0.988, TLI = 0.987, RMSEA = 0.032, 90% CI (0.028, 0.036). HIV/sexual health community engagement was associated with frequency of condom use, which was directly mediated by condom use peer norms and indirectly through self-efficacy. CONCLUSION: The study suggests that condom use peer norms and self-efficacy may be mediators in the pathway between community engagement and condom use, and suggests the importance of peer-based interventions to improve condom use.


Assuntos
Preservativos/estatística & dados numéricos , Homossexualidade Masculina/psicologia , Sexo Seguro/psicologia , Autoeficácia , Normas Sociais , Adolescente , Adulto , China , Estudos Transversais , Infecções por HIV/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Grupo Associado , Fatores Socioeconômicos
16.
Proc IEEE Inst Electr Electron Eng ; 103(2): 205-224, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27746484

RESUMO

Untethered robots miniaturized to the length scale of millimeter and below attract growing attention for the prospect of transforming many aspects of health care and bioengineering. As the robot size goes down to the order of a single cell, previously inaccessible body sites would become available for high-resolution in situ and in vivo manipulations. This unprecedented direct access would enable an extensive range of minimally invasive medical operations. Here, we provide a comprehensive review of the current advances in biome dical untethered mobile milli/microrobots. We put a special emphasis on the potential impacts of biomedical microrobots in the near future. Finally, we discuss the existing challenges and emerging concepts associated with designing such a miniaturized robot for operation inside a biological environment for biomedical applications.

17.
Sci Robot ; 9(88): eadi5155, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478591

RESUMO

Wireless millimeter-scale robots capable of navigating through fluid-flowing tubular structures hold substantial potential for inspection, maintenance, or repair use in nuclear, industrial, and medical applications. However, prevalent reliance on external powering constrains these robots' operational range and applicable environments. Alternatives with onboard powering must trade off size, functionality, and operation duration. Here, we propose a wireless millimeter-scale wheeled robot capable of using environmental flows to power and actuate its long-distance locomotion through complex pipelines. The flow-powering module can convert flow energy into mechanical energy, achieving an impeller speed of up to 9595 revolutions per minute, accompanied by an output power density of 11.7 watts per cubic meter and an efficiency of 33.7%. A miniature gearbox module can further transmit the converted mechanical energy into the robot's locomotion system, allowing the robot to move against water flow at an average rate of up to 1.05 meters per second. The robot's motion status (moving against/with flow or pausing) can be switched using an external magnetic field or an onboard mechanical regulator, contingent on different proposed control designs. In addition, we designed kirigami-based soft wheels for adaptive locomotion. The robot can move against flows of various substances within pipes featuring complex geometries and diverse materials. Solely powered by flow, the robot can transport cylindrical payloads with a diameter of up to 55% of the pipe's diameter and carry devices such as an endoscopic camera for pipeline inspection, a wireless temperature sensor for environmental temperature monitoring, and a leak-stopper shell for infrastructure maintenance.

18.
Biotechnol J ; 19(1): e2300273, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37702130

RESUMO

The chip-based digital polymerase chain reaction (PCR) is an indispensable technique for amplifying and quantifying nucleic acids, which has been widely employed in molecular diagnostics at both fundamental and clinical levels. However, the previous designs have yet to achieve widespread application due to limitations in complex chip fabrication, pretreatment procedures, special surface properties, and low throughput. This study presents a facile digital microfluidic chip driven by centrifugal force for digital PCR analysis. Interestingly, regardless of the hydrophilicity or hydrophobicity of the inner chip surface, an efficient digitization process can be achieved. PCR reagents introduced into the inlet can be allocated to 9600 microchambers and subsequently isolated by the immiscible phase (silicone oil). The centrifugal priming approach offers a facile means to achieve high-throughput analysis. The design was further employed for the quantification of nucleic acids using digital PCR. The calculated result exhibited a strong correlation with the measured value at the concentrations from 1 copy/µL to 1000 copies/µL (R2  = 0.99). Additionally, the chip also allowed digital multiplexed analysis, thereby indicating its potential for multi-target detection applications.


Assuntos
Técnicas Analíticas Microfluídicas , Ácidos Nucleicos , Microfluídica , Reação em Cadeia da Polimerase/métodos , Ácidos Nucleicos/genética , Análise de Sequência com Séries de Oligonucleotídeos , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/métodos
19.
Lab Chip ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953554

RESUMO

The in vitro recapitulation of tumor microenvironment is of great interest to preclinical screening of drugs. Compared with culture of cell lines, tumor organ slices can better preserve the complex tumor architecture and phenotypic activity of native cells, but are limited by their exposure to fluid shear and gradual degradation under perfusion culture. Here, we established a decellularized liver matrix (DLM)-GelMA "sandwich" structure and a perfusion-based microfluidic platform to support long-term culture of tumor slices with excellent structural integrity and cell viability over 7 days. The DLM-GelMA was able to secrete cytokines and growth factors while providing shear protection to the tumor slice via the sandwich structure, leading to the preservation of the tumor microenvironment where immune cells (CD3, CD8, CD68), tumor-associated fibroblasts (α-SMA), and extracellular matrix components (collagen I, fibronectin) were well maintained. Furthermore, this chip presented anti-tumor efficacy at cisplatin (20 µM) on tumor patients, demonstrating our platform's efficacy to design patient-specific treatment regimens. Taken together, the successful development of this DLM-GelMA sandwich structure on the chip could faithfully reflect the tumor microenvironment and immune response, accelerating the screening process of drug molecules and providing insights for practical medicine.

20.
Adv Mater ; : e2405178, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38762788

RESUMO

Graphyne (GY) and graphdiyne (GDY)-based monolayers represent the next generation 2D carbon-rich materials with tunable structures and properties surpassing those of graphene. However, the detection of band formation in atomically thin GY/GDY analogues has been challenging, as both long-range order and atomic precision have to be fulfilled in the system. The present work reports direct evidence of band formation in on-surface synthesized metallated Ag-GDY sheets with mesoscopic (≈1 µm) regularity. Employing scanning tunneling and angle-resolved photoemission spectroscopies, energy-dependent transitions of real-space electronic states above the Fermi level and formation of the valence band are respectively observed. Furthermore, density functional theory (DFT) calculations corroborate the observations and reveal that doubly degenerate frontier molecular orbitals on a honeycomb lattice give rise to flat, Dirac and Kagome bands close to the Fermi level. DFT modeling also indicates an intrinsic band gap for the pristine sheet material, which is retained for a bilayer with h-BN, whereas adsorption-induced in-gap electronic states evolve at the synthesis platform with Ag-GDY decorating the (111) facet of silver. These results illustrate the tremendous potential for engineering novel band structures via molecular orbital and lattice symmetries in atomically precise 2D carbon materials.

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