A new nanoscale architecture of Fe3O4-carbon hybrid materials was developed by a vacuum incipient wetness procedure. The amount of Fe3O4 nanoparticles were controllably confined inside the cavity of ...the bowl-shaped hollow porous carbon nanocapsules (CNB). TEM images and TG curves proved that different loading of Fe3O4 small nanoparticles (NPs) with a diameter less than 50 nm were stored in CNB. Benefiting from the synergistic effect of the appropriate amount of uniformly dispersed Fe3O4 NPs and bowl-shaped carbon nano-capsules with high specific surface area, high conductivity and high amount of Nitrogen (N) and oxygen (O) elemental doping of Fe3O4@CNB, the new architecture provides good reversibility for the transport of electrolyte ions. When tested in supercapacitor devices, Fe3O4@CNB-2 (containing 40.3 wt% Fe3O4) exhibited the highest gravimetric (466 F g−1) and volumetric capacitance (624 F cm−3). The supercapacitors based on these materials also showed excellent cycling stability (92.4% capacitance retention after 5000 cycles). This class of Fe3O4-carbon hybrid materials has excellent electrochemical properties, and its synthesis strategy can be extended to construct other hybrid materials for various applications, such as biomedicine, catalysis, energy harvest, energy storage and so on.
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Research shows that there are important institutional underpinnings for building university-industry linkages. This paper aims to understand how China is developing the relevant organizational ...structures and incentives in its universities. What academic institutions shape the scope and channels of university-industry linkages? What incentives do universities provide to encourage and facilitate faculty engagement with industry? My analysis is accomplished through content analysis of university documents and in-depth interviews with personnel in two top institutions—Fudan University and Shanghai Jiaotong University, supplemented by official statistics. It shows that the hybrid organizational structure to manage technology transfer is a product of historical legacy and institutional learning—parts uniquely Chinese and parts adapted from the West. Faculty incentives also have varied effects. In spite of being enticed to disclose inventions and pursue commercialization, faculty remains keener on scholarly publications.
A greenhouse gas sensor has been developed to simultaneously detect multiple gas species within a hollow-core photonic bandgap fiber (HC-PBF) structure entirely composed of fibers. To enhance ...sensitivity, the gas cell consists of HC-PBF enclosed between two single-mode fibers fused with a reflective end surface to double the absorption length. The incorporation of side holes for gas diffusion allows for analysis of the relationship between gas diffusion speed, number of drilled side holes, and energy loss. As the number of drilled holes increases, the response time decreases to less than 3 min at the expense of energy loss. Gas experiments demonstrated detection limits of 0.1 ppm for methane and 2 ppm for carbon dioxide, with an average time of 50 s. In-situ testing conducted in rice fields validates the effectiveness of the developed gas detection system using HC-PBF cells, establishing all-fiber sensors with high sensitivity and rapid response.
In recent years, passive wireless sensors have been studied for various infrastructure sectors, making them a research and development focus. While substantial evidence already supports their ...viability, further effort is needed to understand their dependability and applicability. As a result, issues related to the theory and implementation of wireless sensors still need to be resolved. This paper aims to review and summarize the progress of the different materials used in different passive sensors, the current status of the passive wireless sensor readout devices, and the latest peripheral devices. It will also cover other related aspects such as the system equipment of passive wireless sensors and the nanogenerators for the energy harvesting for self-powered sensors for applications in contemporary life scenarios. At the same time, the challenges for future developments and applications of passive wireless are discussed.
Transition metal dichalcogenides (TMD), analogue of graphene, could form various dimensionalities. Similar to carbon, one-dimensional (1D) nanotube of TMD materials has wide application in hydrogen ...storage, Li-ion batteries, and supercapacitors due to their unique structure and properties. Here we demonstrate the feasibility of tungsten disulfide nanotubes (WS2-NTs)/graphene (GS) sandwich-type architecture as anode for lithium-ion batteries for the first time. The graphene-based hierarchical architecture plays vital roles in achieving fast electron/ion transfer, thus leading to good electrochemical performance. When evaluated as anode, WS2–NTs/GS hybrid could maintain a capacity of 318.6 mA/g over 500 cycles at a current density of 1A/g. Besides, the hybrid anode does not require any additional polymetric binder, conductive additives, or a separate metal current-collector. The relatively high density of this hybrid is beneficial for high capacity per unit volume. Those characteristics make it a potential anode material for light and high-performance lithium-ion batteries.
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•A Wireless-controlled robotic hand motion system composed of a glove with flexible force sensors and a 3D printed robotic arm. The user wearing the glove could guide the action of ...the 3D printed robotic arm. The 3D printed arm simultaneously acted following the motion of the glove.•The 3D printed arm was built up with 46 individual parts that were printed with white biodegradable polylactic acid (PLA) material.•Few components made the system easy to control, robust and low cost with high accuracy and sensitivity.•The robotic arm followed the action correctly with a maximum 0.133 ms time delay all the time.•This system would probably be helpful for people who work in a dangerous environment for their jobs, disabled people or elder people in their daily lives.
Hand gesture recognition is an emerging field of technology in robotics and human-computer interaction. It has tremendous applications in daily life activities and intelligent workplaces. In this study, a system which could help people to work and operate without directly using hands or contacting by hands, is proposed and demonstrated. This system composed of a glove with flexible force sensors and a 3D printed robotic forearm. The user wearing the glove could control the action of the 3D printed robotic forearm. The 3D printed forearm simultaneously acted following the motion of the glove. The 3D printed forearm was composed of 46 individual parts that were printed with white biodegradable polylactic acid (PLA). Electronic components in the system are five flex sensors, a master Arduino Nano, a slave Arduino Nano, a wireless NRF24L01 transmitter module banding on the glove, a second wireless NRF24L01 receiver module in the forearm and five motors. The five flex sensors on the fingers of the glove detected and collected the signals reflecting the movements of the hands. The Arduino Nano processed the signals from the flex sensors and sent them through the wireless transmitter module to the slave Arduino Nano. In order to control the action of the robotic forearm, it was embedded with a slave Arduino Nano as a control kernel, a wireless NRF24L01 receiver module and five actuators. The slave Arduino Nano received and processed the signals through the wireless receiver module. After that, the signals were sent to the actuators- servo motors. The fingers’ action in the robotics arm was executed with the actuators. After carefully testing the system, the robotic arm followed the action correctly with a maximum 0.133 ms time delay all the time. This system could be really useful for the users who work in dangerous conditions, hazardous environment or require remote operation for safety reasons.
Solar powered steam generation is an emerging area in the field of energy harvest and sustainable technologies. The nano-structured photothermal materials are able to harvest energy from the full ...solar spectrum and convert it to heat with high efficiency. Moreover, the materials and structures for heat management as well as the mass transportation are also brought to the forefront. Several groups have reported their materials and structures as solutions for high performance devices, a few creatively coupled other physical fields with solar energy to achieve even better results. This paper provides a systematic review on the recent developments in photothermal nanomaterial discovery, material selection, structural design and mass/heat management, as well as their applications in seawater desalination and fresh water production from waste water with free solar energy. It also discusses current technical challenges and likely future developments. This article will help to stimulate novel ideas and new designs for the photothermal materials, towards efficient, low cost practical solar-driven clean water production.
Nicotinamide N-methyltransferase (NNMT) is overexpressed in various human tumors and involved in the development and progression of several carcinomas. In breast cancer, NNMT was found to be ...overexpressed in several cell lines. However, the clinical relevance of NNMT in breast cancer is not yet clear.
NNMT expression in breast carcinoma was examined by immunohistochemistry, and then, its relationship with patient clinicopathological characteristics was analyzed. The effects of NNMT on chemoresistance in breast cancer cells were assessed by cell viability, colony formation, and apoptosis assay. The NNMT, SIRT1, p53, and acetyl-p53 proteins, which are involved in NNMT-related chemoresistance, were examined by Western blotting. The SIRT1 mRNA was examined by real-time PCR, and its activity was measured by using the SIRT1 deacetylase fluorometric reagent kit.
NNMT expression was significantly higher (53.9%) in breast carcinoma than in paracancerous tissues (10.0%) and breast hyperplasia (13.3%). A high level of NNMT expression correlated with poor survival and chemotherapy response in breast cancer patients who received chemotherapy. Ectopic overexpression of NNMT significantly inhibited the apoptotic cell death and suppression of colony formation induced by adriamycin and paclitaxel. Mechanistic studies revealed that NNMT overexpression increased SIRT1 expression and promoted its activity. Either inhibition of SIRT1 by EX527 or knockdown of SIRT1 by siRNA could reverse NNMT-mediated resistance to adriamycin and paclitaxel, which suggests that SIRT1 plays a critical role in NNMT-related chemoresistance in breast cancer.
The results of this study demonstrate a novel correlation between the NNMT expression level and patient survival, suggesting that NNMT has the potential to become a new prognostic biomarker to predict the treatment outcomes of the clinical chemotherapy in breast cancer. Moreover, targeting NNMT or downstream SIRT1 may represent a new therapeutic approach to improve the efficacy of breast cancer chemotherapy.
This paper studies the multi-period mean-variance (MV) asset-liability portfolio management problem (MVAL), in which the portfolio is constructed by risky assets and liability. It is worth mentioning ...that the impact of general correlation is considered, i.e., the random returns of risky assets and the liability are not only statistically correlated to each other but also correlated to themselves in different time periods. Such a model with a general correlation structure extends the classical multi-period MVAL models with assumption of independent returns. The authors derive the explicit portfolio policy and the MV efficient frontier for this problem. Moreover, a numerical example is presented to illustrate the efficiency of the proposed solution scheme.
This essay conducts a bibliometric study on innovation research in organizations within the three levels (i.e., individual, work team, and organizational) by using CiteSpace software to analyze 6,354 ...academic articles from the year 2000 to 2020 in four aspects: temporal distribution of published papers, scientific community (countries/regions/cited authors), intellectual structure (cited journals/cited references), and research hotspots. The research findings show that the total number and the growth rate of publications at the organizational level are far higher than the other two levels (individual and work team). The top three countries with the number of publications are United States, China, and United Kingdom. The top five highly cited authors are identified and listed from individual, work team, and organizational levels.
and
are the top two highly cited journals at all three levels (i.e., individual, work team, and organizational levels). The most highly cited articles at the three levels are about topics of linking empowering leadership and employee creativity, team-level predictors of innovation at work, and organizational ambidexterity. The top three research hotspots are identified and listed from individual, work team, and organizational levels. These findings provide snapshots and comparisons of innovation research in management within the three levels (i.e., individual, work team, and organizational levels), which might be beneficial for researchers and scholars to understand and explore innovative behavior in organizations from a multilevel perspective.
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