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1.
Work ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38905076

RESUMO

BACKGROUND: Frontline supervisors have the most frequent interactions with workers on construction projects. Although Supervisors' Safety Leadership (SSL) is commonly practiced, its specific inter-relationship with workers' safety violations remains unclear, especially when it comes to detailed interactions between supervisors and workers, such as supervisors' safety coaching/safety controlling/safety caring against workers' situational/routine safety violations. OBJECTIVE: This study aims to uncover the intrinsic relationship between SSL and safety violations from the perspective of construction workers with the help of mediating variables at both organizational and individual levels. METHODS: A questionnaire survey was conducted to test all hypotheses based on empirical data from 346 construction workers. The path coefficient of the fitted model was then analyzed, including associated mediating effects. RESULTS: Situational safety violations are directly affected only by safety caring (ß= -0.161, p < 0.05), while routine safety violations are impacted only by safety coaching (ß= -0.159, p < 0.05). SSL can influence different types of safety violations through differing mediators. In particular, safety coaching acts on individuals' routine safety violations mainly through self-efficacy (ß= 0.199, p < 0.01; standardized indirect effect = -0.121, 95% CI[-0.226, -0.024]); safety controlling is more oriented to influence individuals' situational safety violations through group safety norm (ß= 0.383, p < 0.001; standardized indirect effect = -0.091, 95% CI[-0.177, -0.036]); and safety caring further influences individuals' situational safety violations mainly through safety motivation (ß= 0.581, p < 0.001; standardized indirect effect = -0.263, 95% CI[-0.418, -0.146]). CONCLUSION: The research enhances existing knowledge by clarifying the complex relationships between supervisor behavior and safety outcomes, particularly from the perceptions of construction workers towards supervisors' actions and leadership.

2.
Micromachines (Basel) ; 15(6)2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38930720

RESUMO

Whispering gallery mode (WGM) resonators have high-quality factors and can be used in high-sensitivity sensors due to the narrow line width that allows for the detection of small external changes. In this paper, a force-sensing system based on a high-Q asymmetric V-shaped CaF2 resonator is proposed. Based on the dispersion coupling mechanism, the deformation of the resonator is achieved by loading force, and the resonant frequency is changed to determine the measurement. By adjusting the structural parameters of the asymmetric V-shaped resonator, the deformation of the resonator under force loading is improved. The experimental results show that the sensitivity of the V-shaped tip is 18.84 V/N, which determines the force-sensing resolution of 8.49 µN. This work provides a solution for force-sensing measurements based on a WGM resonator.

3.
Opt Express ; 32(4): 4816-4826, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439224

RESUMO

In this paper, a simple sensing method based on a silicon oxide microcavity optomechanical oscillator (OMO) is proposed and demonstrated for the detection of acoustic signals. Firstly, the resonance damping was reduced by improving the optical quality factor (Qo) and increasing the sphere-to-neck ratio. After optimizing the process, a microsphere OMO was fabricated, which has an ultra-high mechanical quality factor (6.8 × 106) and greater sphere-to-neck ratio (∼11:1), based on which ultra-narrow linewidth phonon laser (∼1 Hz) is constructed. Secondly, by changing the refractive index of the coupling interval, the low-frequency acoustic pressure signal is efficiently coupled into the microcavity OMO to construct a high-resolution acoustic sensor. This sensing mechanism can not only measure the acoustic pressure, but also use the sideband signal in the modulation mechanism to measure the frequency of acoustic signals (15 Hz∼16 kHz), the sensitivity is 10.3 kHz/Pa, the minimum detectable pressure is 1.1 mPa, and noise-limited minimum detectable pressure is 28.8 µPa/Hz1/2. It is the highest detection resolution compared with the same type of low-frequency acoustic signal detection currently reported. This OMO-based acoustic sensing detection method opens up a new path for future miniaturized, ultra-high-precision, and cost-effective acoustic sensing.

4.
Glob Chang Biol ; 30(1): e17140, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273497

RESUMO

Growing evidence suggests that liana competition with trees is threatening the global carbon sink by slowing the recovery of forests following disturbance. A recent theory based on local and regional evidence further proposes that the competitive success of lianas over trees is driven by interactions between forest disturbance and climate. We present the first global assessment of liana-tree relative performance in response to forest disturbance and climate drivers. Using an unprecedented dataset, we analysed 651 vegetation samples representing 26,538 lianas and 82,802 trees from 556 unique locations worldwide, derived from 83 publications. Results show that lianas perform better relative to trees (increasing liana-to-tree ratio) when forests are disturbed, under warmer temperatures and lower precipitation and towards the tropical lowlands. We also found that lianas can be a critical factor hindering forest recovery in disturbed forests experiencing liana-favourable climates, as chronosequence data show that high competitive success of lianas over trees can persist for decades following disturbances, especially when the annual mean temperature exceeds 27.8°C, precipitation is less than 1614 mm and climatic water deficit is more than 829 mm. These findings reveal that degraded tropical forests with environmental conditions favouring lianas are disproportionately more vulnerable to liana dominance and thus can potentially stall succession, with important implications for the global carbon sink, and hence should be the highest priority to consider for restoration management.


Des preuves de plus en plus nombreuses suggèrent que la competition entre lianes et les arbres menace le puits de carbone mondial en ralentissant la récupération des forêts après une perturbation. Une théorie récente, fondée sur des observations locales et régionales, propose en outre que le succès compétitif des lianes sur les arbres est dû aux interactions entre la perturbation forestière et le climat. Nous présentons la première évaluation mondiale de la performance relative des lianes par rapport aux arbres en réponse aux perturbations forestières et aux facteurs climatiques. En utilisant un ensemble de données sans précédent, nous avons analysé 651 échantillons de végétation représentant 26,538 lianes et 82,802 arbres, issus de 556 emplacements uniques dans le monde entier, tirés de 83 publications. Les résultats montrent que les lianes ont de meilleure performances par rapport aux arbres (augmentation du ratio liane-arbre) lorsque les forêts sont perturbées, sous des zones chaudes aves précipitations faibles, et vers les basses altitudes tropicales. Nous avons également constaté que les lianes peuvent être un facteur critique entravant la récupération des forêts dans les forêts perturbées connaissant des climats favorables aux lianes, car les données de chronoséquence montrent que le succès compétitif élevé des lianes sur les arbres peut persister pendant des décennies après les perturbations, surtout lorsque la température annuelle moyenne dépasse 27.8°C, que les précipitations sont inférieures à 1614 mm et que le déficit hydrique climatique est supérieur à 829 mm. Ces découvertes révèlent que les forêts tropicales dégradées avec des conditions environnementales favorables aux lianes sont disproportionnellement plus vulnérables à la dominance des lianes, et peuvent ainsi potentiellement entraver la succession, avec d'importantes implications pour le puits de carbone mondial et devraient donc être la plus haute priorité à considérer pour la gestion de la restauration.


Assuntos
Árvores , Clima Tropical , Árvores/fisiologia , Florestas , Sequestro de Carbono , Água
5.
Opt Express ; 32(1): 79-91, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175064

RESUMO

In non-Hermitian systems, enhancing sensitivity under exceptional point (EP) conditions offers an ideal solution for reconciling the trade-off between sensitivity and size constraints in sensing applications. However, practical application is limited by undesired sensitivity to external fluctuations, noise, and errors in signal amplification synchronization. This paper presents a precisely controlled EP tracking and detection system (EPTDS) that achieves long-term rapid tracking and locking near the EP by constructing a second-order non-Hermitian optical sensing unit, employing an optical power adaptive control method, and utilizing a combinatorial demodulation-based dual-loop cascaded control (CDCC) technique to selectively suppress traditional noise at different frequencies. The system locking time is 10 ms, and in room temperature conditions, the output frequency error over 1 hour is reduced by more than 30 times compared to before locking. To assess its sensing capabilities, the EPTDS undergoes testing in a rotational experiment based on the Sagnac effect, with the output bias instability based on Allan deviation measured at 0.036 °/h. This is the best result for EP-enhanced angular rate sensing that we are aware of that has been reported. The EPTDS method can be extended to various sensing fields, providing a new path for transitioning non-Hermitian sensing from the laboratory to practical applications.

6.
Microsyst Nanoeng ; 9: 65, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37213821

RESUMO

Acoustic sensors with ultrahigh sensitivity, broadband response, and high resolution are essential for high-precision nondestructive weak signal detection technology. In this paper, based on the size effect of an ultrahigh-quality (Q) calcium fluoride (CaF2) resonator, a weak acoustic signal is detected by the dispersive response regime in which an acoustic, elastic wave modulates the geometry and is converted to a resonance frequency shift. Through the structural design of the resonator, the sensitivity reaches 11.54 V/Pa at 10 kHz in the experiment. To our knowledge, the result is higher than that of other optical resonator acoustic sensors. We further detected a weak signal as low as 9.4 µPa/Hz1/2, which greatly improved the detection resolution. With a good directionality of 36.4 dB and a broadband frequency response range of 20 Hz-20 kHz, the CaF2 resonator acoustic sensing system can not only acquire and reconstruct speech signals over a long distance but also accurately identify and separate multiple voices in noisy environments. This system shows high performance in weak sound detection, sound source localization, sleep monitoring, and many other voice interaction applications.

7.
Phys Chem Chem Phys ; 25(17): 12458-12468, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37096448

RESUMO

Aiming at achieving the concurrent performances of high loading, well controlled release and active targeted delivery, folate (FA) modified dual pH/reduction-responsive mixed polymeric micelles were rationally assembled using FA-PEG-PDEAEMA and PEG-SS-PCL by dissipative particle dynamics (DPD) simulations. The optimized polymers PEG112-PDEAEMA40, FA-PEG112-PDEAEMA40, and PEG112-SS-PCL70 were synthesized and characterized using 1H NMR, FT-IR and GPC, and their mixed micelles were applied for doxorubicin (DOX) delivery. The drug loading capacity (LC) and encapsulation efficiency (EE) values of the MIX1 (FA-PEG112-PDEAEMA40/PEG112-SS-PCL70) at a DOX/polymer feeding ratio of 15 mg/30 mg were 20.22% and 50.69%, which were higher than those of single polymer micelles and MIX2 (PEG112-PDEAEMA40/PEG112-SS-PCL70). Particle size distributions, mesoscopic morphologies, DPD simulations and in vitro drug release profiles all confirmed the well-controlled release performance of the DOX-loaded micelles formed by MIX1: slow DOX release with a cumulative release of 20.46% in the neutral environment and accelerated release with a cumulative release of 74.20% at pH 5.0 + 10 mM DTT within 120 h, which were similar to those of MIX2. Cytotoxicity assay found that both MIX1 and MIX2 blank micelles were biocompatible, and a superior inhibitory effect of the FA-modified DOX-loaded micelles MIX1 on HepG2 cells was found compared to that of free DOX and non-FA-modified DOX-loaded micelles MIX2. All of these confirmed the superiority of MIX1 micelles with high loading capacity, well controlled release, and enhanced inhibitory effects on HepG2 cells, which might be a prospective candidate for anticancer drug delivery.


Assuntos
Ácido Fólico , Micelas , Preparações de Ação Retardada , Ácido Fólico/química , Espectroscopia de Infravermelho com Transformada de Fourier , Doxorrubicina/química , Polietilenoglicóis/química , Polímeros/química , Concentração de Íons de Hidrogênio , Portadores de Fármacos/química , Sobrevivência Celular
8.
Environ Sci Pollut Res Int ; 30(21): 59282-59300, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37004614

RESUMO

Prefabricated buildings (PBs) contribute to sustainable development, and their development largely depends on the active participation of developers. However, based on the characteristics of different stages of PBs' development and the goals of "14th Five-Year Plan" for architecture in China, it is an urgent practical problem for the government to encourage developers' active participation while regulating their alienation behavior. To address such problem, this paper uses the evolutionary game method to explore the government's reasonable regulatory strategies for developers' behavior in different development stages of PBs. Meanwhile, this paper explores the boundary of government's regulatory strength on PBs based on actual situation in China, which help the government to drive high-quality development of PBs with effective policy resources. Results reveal that the strict regulatory strategies have limited effects in the incubation stage of PBs. In the growth stage, it is necessary to adjust the regulatory strategies appropriately. The dynamic linear regulatory strategy can enable the PBs to achieve the phased goal, and the dynamic nonlinear regulatory strategy can help to achieve the optimal goal of PBs in China. In the maturity stage, the government does not need to deliberately regulate due to the considerable profits of developers. The regulatory strategy of "light reward and heavy punishment" is better when it is adopted to promote the development of PBs in the growth stage. The research also provides valuable suggestions for government regulators to formulate reasonable and dynamic regulatory policies for PBs.


Assuntos
Governo , Desenvolvimento Sustentável , China
9.
Appl Opt ; 62(3): 820-825, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36821289

RESUMO

Whispering gallery mode (WGM) resonators with an ultrahigh quality (Q) factor provide an extremely high resolution for high-precision sensing. However, it is difficult to use them directly in magnetic sensors because of the transparency to the magnetic field. In this paper, a sandwich structure consisting of a neodymium iron boron magnet and calcium fluoride resonator with a Q factor of 109 is proposed. The experimental results show that, compared with the conventional magnetometer, the signal-to-noise ratio of the optical WGM magnetometer reaches 62 dB, with the direct current sensitivity of 42.59 MHz/mT and the AC sensitivity of 794p T H z -1/2 at 42 kHz.

10.
Appl Opt ; 62(6): 1492-1496, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36821309

RESUMO

Whispering-gallery-mode crystalline resonators currently maintain the best quality factor (Q) record; however, compact on-chip packaging is still a challenge, although various coupling architectures have been developed. Here, a chemical etching method is proposed to fabricate a miniaturized tapered fiber waveguide on silicon substrate. The Marangoni effect is implemented to reduce the surface roughness of the cone region. The optical loss of 0.1 dB/mm is obtained, and the Q of the on-chip crystalline resonator exceeds 108. Additionally, thermoelectric cooler (TEC) is implanted in the package to actively customize the temperature, and the temperature response of 18 pm/°C is consistent with the theoretical calculation.

11.
New Phytol ; 236(2): 714-728, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35811425

RESUMO

Hemiepiphytic figs killing their host trees is an ecological process unique to the tropics. Yet the benefits and adaptive strategies of their special life history remain poorly understood. We compared leaf phosphorus (P) content data of figs and palms worldwide, and functional traits and substrate P content of hemiepiphytic figs (Ficus tinctoria), their host palm and nonhemiepiphytic conspecifics at different growth stages in a common garden. We found that leaf P content of hemiepiphytic figs and their host palms significantly decreased when they were competing for soil resources, but that of hemiepiphytic figs recovered after host death. P availability in the canopy humus and soil decreased significantly with the growth of hemiepiphytic figs. Functional trait trade-offs of hemiepiphytic figs enabled them to adapt to the P shortage while competing with their hosts. From the common garden to a global scale, the P competition caused by high P demand of figs may be a general phenomenon. Our results suggest that P competition is an important factor causing host death, except for mechanically damaging and shading hosts. Killing hosts benefits hemiepiphytic figs by reducing interspecific P competition and better acquiring P resources in the P-deficient tropics, thereby linking the life history strategy of hemiepiphytic figs to the widespread P shortage in tropical soils.


Assuntos
Ficus , Vespas , Animais , Fósforo , Folhas de Planta , Solo , Árvores
12.
Micromachines (Basel) ; 13(4)2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-35457932

RESUMO

This paper presents a novel resonant magnetic sensor consisting of a graphene nanomechanical oscillator and magnetostrictive stress coupling structure, using Si/SiO2 substrate and Fe-Ga alloy, respectively. In this device, the deformation of the Fe-Ga alloy resulting from the external magnetic field changed the surface tension of the graphene, resulting in a significant change in the resonance frequency of graphene. Using the finite element analysis, it could be found that the response of the resonance frequency revealed a good linear relationship with the external magnetic field (along the x-axis) in the range of the 1 to 1.6 mT. By optimizing the sizes of each component of the magnetic sensor, such as the thickness of the Si/SiO2 substrate and the Fe-Ga alloy, and the length of the graphene, the sensitivity could even reach 834 kHz/mT, which is three orders of magnitude higher than conventional resonant magnetic devices. This provides a new method for highly sensitive and miniaturized magnetic sensors.

13.
Appl Opt ; 61(32): 9449-9454, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36606890

RESUMO

As a key component of the beam splitting and combining in photonic integrated circuits, an optical power splitter requires the characteristics of compactness, broadband, and low loss. Here, we propose a 1×2 ultra-broadband 3 dB power splitter with a 5 µm long beam splitting area, based on the structure of a subwavelength grating. The 0.45 dB bandwidth of the TE mode achieves 790 nm from 1.25 to 2.04 µm. This power splitter has a large fabrication tolerance, exceeding more than 30 nm (±15n m) and obtains the desired power ratio. It is suitable for high-speed and large-capacity communication, wavelength division multiplexing systems, and other multi-wave interconnection applications.

14.
Front Psychol ; 12: 796295, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34966339

RESUMO

The unsafe behavior of construction workers is one of the most important and direct causes of safety accidents. Managers usually develop effective incentives aimed at regulating worker safety behavior. Due to the large number of workers in construction projects, there are multiple differences in fairness preference, risk preference and ability level, which will lead to the complex effect of the traditional mechanism to regulate workers' safety behavior. In order to improve the effectiveness of incentive measures for worker safety behavior, this paper takes into account the multiple differences of individual workers' fairness preference, risk preference and ability level, based on the tournament mechanism to construct a competition incentive model. By designing a tournament reward and salary distribution for heterogeneous workers, the occurrence of unsafe behaviors can be reduced. The study found that in terms of the optimal level of safety investment, workers with risk aversion attitude generally invest higher than that of workers with risk preference, no matter whether they have a strong fairness preference or not; In terms of the distribution of tournament rewards, workers with a risk aversion attitude and a higher level of fairness preference need to be given higher incentives.

15.
BMC Cancer ; 21(1): 1228, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34781924

RESUMO

BACKGROUND: Competitive Endogenous RNA (ceRNA) may be closely associated with tumor progression. However, studies on ceRNAs and immune cells in LUAD are scarce. METHOD: The profiles of gene expression and clinical data of LUAD patients were extracted from the TCGA database. Bioinformatics methods were used to evaluate differentially-expressed genes (DEGs) and to form a ceRNA network. Preliminary verification of clinical specimens was utilized to detect the expressions of key biomarkers at the tissues. Cox and Lasso regressions were used to identify key genes, and prognosis prediction nomograms were formed. The mRNA levels of 9 genes in the risk score model in independent clinical LUAD samples were detected by qRT-PCR. The interconnection between the risk of cancer and immune cells was evaluated using the CIBERSORT algorithm, while the conformation of notable tumor-infiltrating immune cells (TIICs) in the LUAD tissues of the high and low risk groups was assessed using the RNA transcript subgroup in order to identify tissue types. Finally, co-expression study was used to examine the interconnection between the key genes in the ceRNA networks and the immune cells. RESULT: A ceRNA network of 115 RNAs was established, and nine key genes were identified to construct a Cox proportional-hazard model and create a prognostic nomogram. This risk-assessment model might serve as an independent factor to forecast the prognosis of LUAD, and it was consistent with the preliminary verification of clinical specimens. Survival analysis of clinical samples further validated the potential value of high risk groups in predicting LUAD prognosis. Five immune cells were identified with significant differences in the LUAD tissues of the high and low risk groups. Besides, two pairs of biomarkers associated with the growth of LUAD were found, i.e., E2F7 and macrophage M1 (R = 0.419, p = 1.4e- 08) and DBF4 and macrophage M1 (R = 0.282, p < 2.2 e- 16). CONCLUSION: This study identified several important ceRNAs, i.e. (E2F7 and BNF4) and TIICs (macrophage M1), which might be related to the development and prognosis of LUAD. The established risk-assessment model might be a potential tool in predicting LUAD of prognosis.


Assuntos
Adenocarcinoma de Pulmão/genética , Expressão Gênica , Redes Reguladoras de Genes , Neoplasias Pulmonares/genética , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/mortalidade , Algoritmos , Progressão da Doença , Humanos , Imunidade Celular , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/mortalidade , Linfócitos do Interstício Tumoral , MicroRNAs , Nomogramas , Análise de Regressão , Medição de Risco , Análise de Sobrevida
16.
Nat Commun ; 12(1): 6312, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34728627

RESUMO

For iron-based superconductors, the phase diagrams under pressure or strain exhibit emergent phenomena between unconventional superconductivity and other electronic orders, varying in different systems. As a stoichiometric superconductor, LiFeAs has no structure phase transitions or entangled electronic states, which manifests an ideal platform to explore the pressure or strain effect on unconventional superconductivity. Here, we observe two types of superconducting states controlled by orientations of local wrinkles on the surface of LiFeAs. Using scanning tunneling microscopy/spectroscopy, we find type-I wrinkles enlarge the superconducting gaps and enhance the transition temperature, whereas type-II wrinkles significantly suppress the superconducting gaps. The vortices on wrinkles show a C2 symmetry, indicating the strain effects on the wrinkles. By statistics, we find that the two types of wrinkles are categorized by their orientations. Our results demonstrate that the local strain effect with different directions can tune the superconducting order parameter of LiFeAs very differently, suggesting that the band shifting induced by directional pressure may play an important role in iron-based superconductivity.

17.
Nat Commun ; 12(1): 4146, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34230479

RESUMO

The iron-based superconductor is emerging as a promising platform for Majorana zero mode, which can be used to implement topological quantum computation. One of the most significant advances of this platform is the appearance of large vortex level spacing that strongly protects Majorana zero mode from other low-lying quasiparticles. Despite the advantages in the context of physics research, the inhomogeneity of various aspects hampers the practical construction of topological qubits in the compounds studied so far. Here we show that the stoichiometric superconductor LiFeAs is a good candidate to overcome this obstacle. By using scanning tunneling microscopy, we discover that the Majorana zero modes, which are absent on the natural clean surface, can appear in vortices influenced by native impurities. Our detailed analysis reveals a new mechanism for the emergence of those Majorana zero modes, i.e. native tuning of bulk Dirac fermions. The discovery of Majorana zero modes in this homogeneous material, with a promise of tunability, offers an ideal material platform for manipulating and braiding Majorana zero modes, pushing one step forward towards topological quantum computation.

18.
Colloids Surf B Biointerfaces ; 204: 111797, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33957490

RESUMO

Delivery of anticancer drugs by amphiphilic polymeric micelles with disulfide bonds as the reduction-responsive groups has potential application in the field of drug-controlled release. In this study, three disulfide-linked polycaprolactone-b-polyethylene glycol methyl ether methacrylate (PCL-SS-PPEGMA) were synthesized and confirmed by 1H NMR and GPC, and then used for doxorubicin (DOX) delivery. The CMC values of the three PCL-SS-PPEGMA micelles were low (0.71-4.56 mg/L), indicative of the good stability of micelles in aqueous solution. The drug loading content (LC) and encapsulation efficiency (EE), together with the DOX accelerated release profiles were determined, with good drug loading capacity and well drug-controlled release performance. And to explore the mesoscopic behavior of reduction-responsive drug-loaded polymeric micelles, by using a dedicated disulfide bond-breaking model and script, dissipative particle dynamics (DPD) simulations were carried out on the three PCL-SS-PPEGMA polymers. Their self-assembled behavior, formation of DOX-loaded micelles, the disulfide bond-breaking process, as well as the DOX reduction-responsive release process were simulated and assessed. Comparing the DPD simulation results with the experimental data, we found that they were in good agreement, effectively demonstrating that the DPD simulation method developed can provide a practical mesoscopic approach for the reduction-responsive drug-loaded polymeric micelles that involved the cleavage of dynamic covalent bonds.


Assuntos
Doxorrubicina , Micelas , Preparações de Ação Retardada , Portadores de Fármacos , Concentração de Íons de Hidrogênio , Polietilenoglicóis , Polímeros , Ácidos Polimetacrílicos
19.
Artigo em Inglês | MEDLINE | ID: mdl-33807980

RESUMO

Unsafe behaviors of construction workers are one of the main causes of accidents at construction sites. The research on unsafe behaviors of workers helps to reduce the incidence of accidents and has attracted much attention. However, a systematic literature review in this field is still lacking, which hinders stakeholders' comprehensive understanding of the unsafe behaviors of construction workers. Therefore, the aim of this study is to address this research gap based on retrieved literature from the Web of Science. First, the study conducted a descriptive analysis of the year, quantity, publishing organization, and keywords of the literature. In addition, three research topics were identified and discussed, including the influencing factors of construction workers' unsafe behaviors, the formation mechanism of unsafe behaviors, and the pre-control methods of unsafe behaviors. Moreover, a research framework was proposed and future research directions were also suggested. The research findings promote stakeholders' understanding of the influencing factors, formation mechanism, and pre-control methods of construction workers' unsafe behaviors, and lead to future research directions in the studied field.


Assuntos
Indústria da Construção , Saúde Ocupacional , Acidentes de Trabalho/prevenção & controle , Humanos , Comportamento Social , Local de Trabalho
20.
Appl Opt ; 60(10): 2761-2766, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33798149

RESUMO

In a resonator micro-optic gyroscope (R-MOG), backscattering noise and Kerr noise have been key issues affecting the optical gyro output that are difficult to completely suppress. A method is proposed to suppress backscattering noise in a R-MOG. It uses two independent lasers and, by locking the two optical signals at different resonance peaks, a differential output of the two optical signals is achieved that successfully suppresses the backscattering noise. At the same time, a light intensity feedback loop based on a light intensity modulator is added to the loop to ensure the same optical power into the cavity. Experimental results show that the light intensity fluctuation into the gyro system is reduced nearly two orders of magnitude and the bias stability is improved to 9.06 deg/h by using a light intensity feedback loop with two independent lasers.

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