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1.
Sensors (Basel) ; 24(2)2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38276343

RESUMEN

Participatory crowdsensing (PCS) is an innovative data sensing paradigm that leverages the sensors carried in mobile devices to collect large-scale environmental information and personal behavioral data with the user's participation. In PCS, task assignment and path planning pose complex challenges. Previous studies have only focused on the assignment of individual tasks, neglecting or overlooking the associations between tasks. In practice, users often tend to execute similar tasks when choosing assignments. Additionally, users frequently engage in tasks that do not match their abilities, leading to poor task quality or resource wastage. This paper introduces a multi-task assignment and path-planning problem (MTAPP), which defines utility as the ratio of a user's profit to the time spent on task execution. The optimization goal of MATPP is to maximize the utility of all users in the context of task assignment, allocate a set of task locations to a group of workers, and generate execution paths. To solve the MATPP, this study proposes a grade-matching degree and similarity-based mechanism (GSBM) in which the grade-matching degree determines the user's income. It also establishes a mathematical model, based on similarity, to investigate the impact of task similarity on user task completion. Finally, an improved ant colony optimization (IACO) algorithm, combining the ant colony and greedy algorithms, is employed to maximize total utility. The simulation results demonstrate its superior performance in terms of task coverage, average task completion rate, user profits, and task assignment rationality compared to other algorithms.

2.
J Am Chem Soc ; 2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36706380

RESUMEN

Two-dimensional (2D) transition-metal borides (TMBs) are especially expected to exhibit excellent performance in various fields among electricity, superconductivity, magnetism, mechanics, biotechnology, battery, and catalysis. However, the synthesis of ultrathin TMB single crystals with ultrahigh phase purity was deemed extremely challenging and has not been realized till date. That is because TMBs have the most kinds of crystal structures among inorganic compounds, which possess generous phase structures with similar formation energies compared with other transition-metal compounds, attributing to the metalloid and electron-deficient characteristics of boron. Herein, for the first time, we demonstrate a chemical potential-modulated strategy to realize the precise synthesis of various ultrahigh-phase-purity (approximately 100%) ultrathin TMB single crystals, and the precision in the phase formation energy can reach as low as 0.01 eV per atom. The ultrathin MoB2 single crystals exhibit an ultrahigh Young's modulus of 517 GPa compared to other 2D materials. Our work establishes a chemical potential-modulated strategy to synthesize ultrathin single crystals with ultrahigh phase purity, especially those with similar formation energies, and undoubtedly provides excellent platforms for their extensive research and applications.

3.
Sensors (Basel) ; 23(23)2023 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-38067797

RESUMEN

Efficient measurement of labor input is a critical aspect of on-site control and management in construction projects, as labor input serves as the primary and direct determinant of project outcomes. However, conventional manual inspection methods are off-line, tedious, and fail to capture their effectiveness. To address this issue, this research presents a novel method that leverages Inertial Measurement Unit (IMU) sensors attached to hand tools during construction activities to measure labor input in a timely and precise manner. This approach encompasses three steps: temporal-spatial feature extraction, self-similarity matrix calculation, and local specific structure identification. The underlying principle is based on the hypothesis that repetitive use data from hand tools can be systematically collected, analyzed, and converted into quantitative measures of labor input by the automatic recognition of repetition patterns. To validate this concept and assess its feasibility for general construction activities, we developed a preliminary prototype and conducted a pilot study focusing on rotation counting for a screw-connection task. A comparative analysis between the ground truth and the predicted results obtained from the experiments demonstrates the effectiveness and efficiency of measuring labor input using IMU sensors on hand tools, with a relative error of less than 5%. To minimize the measurement error, further work is currently underway for accurate activity segmentation and fast feature extraction, enabling deeper insights into on-site construction behaviors.


Asunto(s)
Proyectos Piloto , Rotación
4.
Opt Express ; 29(16): 24928-24946, 2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34614837

RESUMEN

Based on the hologram inpainting via a two-stage Generative Adversarial Network (GAN), we present a precise phase aberration compensation method in digital holographic microscopy (DHM). In the proposed methodology, the interference fringes of the sample area in the hologram are firstly removed by the background segmentation via edge detection and morphological image processing. The vacancy area is then inpainted with the fringes generated by a deep learning algorithm. The image inpainting finally results in a sample-free reference hologram containing the total aberration of the system. The phase aberrations could be deleted by subtracting the unwrapped phase of the sample-free hologram from our inpainting network results, in no need of any complex spectrum centering procedure, prior knowledge of the system, or manual intervention. With a full and proper training of the two-stage GAN, our approach can robustly realize a distinct phase mapping, which overcomes the drawbacks of multiple iterations, noise interference or limited field of view in the recent methods using self-extension, Zernike polynomials fitting (ZPF) or geometrical transformations. The validity of the proposed procedure is confirmed by measuring the surface of preprocessed silicon wafer with a Michelson interferometer digital holographic inspection platform. The results of our experiment indicate the viability and accuracy of the presented method. Additionally, this work can pave the way for the evaluation of new applications of GAN in DHM.

5.
Nanotechnology ; 31(25): 255604, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32270766

RESUMEN

Encapsulation of metal oxide nanoparticles (MO NPs) inside metal-organic frameworks (MOFs) has been realized successfully via surfactant-assisted nano-confined space strategy, which is a universal method for various MO NPs@MOFs. The size of MO NPs was limited by the confined nano-space and could be adjusted to a certain extent. The synthesis mechanism of MO NPs@MOFs was revealed via detailed structural characterizations and a series of control experiments. Surfactants introduced during MOFs (CuBDC, BDC = 1,4-benzenedicarboxylic acid) formation process plays a very important role in producing uniform voids of nano-confined space. Cu ions in MOF frameworks were directly used as precursors to fabricate CuO NPs in these confined void spaces. The synthesized CuO@CuBDC composites showed excellent catalytic activity in C-S cross-coupling reactions and dye pollutant photo-degradation reactions.

6.
ACS Omega ; 9(23): 24601-24609, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38882132

RESUMEN

Memristor-based neuromorphic computing is promising toward their potential application of handling complex parallel tasks in the period of big data. To implement brain-inspired applications of spiking neural networks, new physical architecture designs are needed. Here, a serial memristive structure (SMS) consisting of memristive devices with different top electrodes is proposed. Top electrodes Au, Cu, and Al are selected for nitrogen-doped TiO2 nanorod array-based memristive devices. The typical I-V cycles, retention, on/off ratio, and variations of cycle to cycle of top electrode-dependent memristive devices have been studied. Devices with Cu and Al electrodes exhibit a retention of over 104 s. And the resistance states of the device with the Al top electrode are reliable. Furthermore, the conductive mechanism underlining the I-V curves is discussed in detail. The interface-type mechanism and block conductance mechanism are illustrated, which are related to electron migration and ion/anion migration, respectively. Finally, the SMS has been constructed using memristive devices with Al and Cu top electrodes, which can mimic the spiking pulse-dependent plasticity of a synapse and a neuron body. The SMS provides a new approach to implement a fundamental physical unit for neuromorphic computing.

7.
Discov Oncol ; 15(1): 26, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38305998

RESUMEN

Gastric cancer (GC) is a heterogeneous disease whose development is accompanied by alterations in a variety of pathogenic genes. The phospholipase C Delta 3 enzyme is a member of the phospholipase C family, which controls substance transport between cells in the body. However, its role in gastric cancer has not been discovered. The purpose of this study was to investigate the expression and mechanism of action of PLCD3 in connection to gastric cancer. By Western blot analysis and immunohistochemistry, PLCD3 mRNA and protein expression levels were measured, with high PLCD3 expression suggesting poor prognosis. In N87 and HGC-27 cells, the silencing of PLCD3 using small interfering RNA effectively induced apoptosis and inhibited tumor cell proliferation, invasion, and migration. Conversely, overexpression of PLCD3 using overexpressed plasmids inhibited apoptosis in AGS and BGC-823 cells and promoted proliferation, migration, and invasion. In order to investigate the underlying mechanisms, we conducted further analysis of PLCD3, which indicates that this protein is closely related to the cell cycle and EMT. Additionally, we found that overexpression of PLCD3 inhibits apoptosis and promotes the development of GC cells through JAK2/STAT3 signaling. In conclusion, PLCD3 inhibits apoptosis and promotes proliferation, invasion, and migration, which indicated that PLCD3 might serve as a therapeutic target for gastric cancer.

8.
Artículo en Inglés | MEDLINE | ID: mdl-24432588

RESUMEN

The work relates to assessing the ability of the microwave for dehydration of large amount of waste hydrous ferrous sulfate generated from the titanium pigment process industry. The popular process optimization tool of response surface methodology with central composite design was adopted to estimate the effect of dehydration. The process variables were chosen to be power input, duration of heating and the bed thickness, while the response variable being the weight loss. An increase in all the three process variables were found to significantly increase the weight loss, while the effect of interaction among the parameters were found to be insignificant. The optimized process conditions that contribute to the maximum weight loss were identified to be a power input of 960 W, duration of heating of 14 min and bed thickness of 5 cm, resulting in a weight loss of 31.44%. The validity of the optimization process was tested with the repeat runs at optimized conditions.


Asunto(s)
Técnicas Químicas Combinatorias/métodos , Desecación/métodos , Compuestos Ferrosos/química , Compuestos Ferrosos/aislamiento & purificación , Calefacción/métodos , Residuos Industriales/prevención & control , Modelos Químicos , Agua/química , Simulación por Computador , Compuestos Ferrosos/efectos de la radiación , Ensayo de Materiales , Modelos Estadísticos
9.
Adv Mater ; 34(20): e2108396, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35306696

RESUMEN

Perovskites have engaged significant attention owing to rich species and remarkable physical properties as well as optoelectronic applications. Compared to bulk counterparts, ultrathin perovskites exhibit more available compositions due to the breaking of bulk lattice limitation. Coupled with crystal lattice relaxation and quantum confinement, infinite intriguing properties of ultrathin perovskites deserve to be explored. Developing ultrathin perovskites with alterable composition and structure is a necessity to fully explore this versatile family. Herein, a universal strategy is conceived via constructing oriented solvent microenvironment induced by the interfacial electric field originated from the charge separation between solid and liquid phases, which is conducive to controlling the precursor distribution and makes crystals preferentially nucleate and grow in the preferentially lateral mode. From layered to nonlayered, organic to inorganic, and toxic to low-toxic lead-free perovskite, a full-range synthesis is achieved of ultrathin perovskites. This work opens up opportunities both for ultrathin perovskite exploration through compositional engineering and for device miniaturization in energy conversion applications.

10.
Transpl Immunol ; 27(4): 151-6, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23063462

RESUMEN

The reason why delayed RBC engraftment and pure red cell aplasia (PRCA) develop only in some but not all recipients of major ABO-incompatible hematopoietic stem cell transplantation (HSCT) remains elusive and the underlying mechanisms are not fully understood. Understanding how incompatible erythroid blood group antibodies (Abs) interact with ABH antigens (Ags) of grafts, and investigating how to induce artificially accommodation of grafts are of obvious importance in transplantation immunology. The effects of anti-H on proliferation, apoptosis, and α-(1,2)-fucosyltransferase gene (FUT1) expression in erythroid differentiated K562 cells were analyzed by the MTT assay, Annexin V/PI staining, and quantitative RT-PCR method. The growth of erythroid differentiated K562 cells was significantly suppressed when anti-H dilution was ≤ 1:8 (P<0.001, as compared with 1:16). Under the complement-free culture conditions, the apoptotic ratio of erythroid differentiated K562 cells was significantly increased when anti-H dilution was ≤ 1:16 (P<0.05, as compared with 1:32). The apoptosis was not only closely associated with anti-H dilution (F=138.991, P<0.001), but also correlated with treated time (F=583.249, P<0.001), which indicated typical dose- and time-dependent effects. Under the complement-free culture conditions, the FUT1 mRNA expression level was also suppressed when anti-H dilution was ≤ 1:16 (P<0.05, as compared with 1:32), which also manifested in typical dose-dependent (F=130.356, P<0.001) and time-dependent (F=1432.00, P<0.001) effects. The results confirm that anti-H can trigger apoptosis and down-regulate FUT1 expression in erythroid differentiated K562 cells without complement mediation. The findings suggest that anti-H could accommodate grafts through triggering apoptosis and down-regulating Fut1 expression to reduce ABH antigens.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Células Eritroides/inmunología , Células Eritroides/metabolismo , Fucosiltransferasas/genética , Isoanticuerpos/inmunología , Sistema del Grupo Sanguíneo ABO/metabolismo , Apoptosis/inmunología , Secuencia de Bases , Diferenciación Celular , Proliferación Celular , Proteínas del Sistema Complemento/metabolismo , Regulación hacia Abajo , Células Eritroides/citología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Células K562 , ARN Mensajero/genética , ARN Mensajero/metabolismo , Inmunología del Trasplante , Galactósido 2-alfa-L-Fucosiltransferasa
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