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In recent years, the development of Brain-Computer Interface (BCI) technology has attracted significant attention, particularly in the acquisition and application of electroencephalogram (EEG) signals. Most pertinent studies have utilized EEG to monitor neural activity states. Given that EEG does not provide direct insights into the physical states of body structures, many researchers have refrained from employing EEG to assess structural body states such as Body Mass Index (BMI). This study, for the first time, employs portable EEG detection devices combined with machine learning algorithms such as Logistic Regression (LR), Naive Bayes (NB), and Support Vector Machine (SVM) to process EEG features, enabling the application of EEG in identifying BMI. We collected EEG data from three different states: resting state, free imagination, and viewing pictures. The results demonstrate that these EEG signals can effectively differentiate subjects with higher BMI. Particularly under visual stimulation, EEG features exhibited optimal performance when subjects viewed images of high-calorie foods, with the model achieving an average accuracy of 80% and an F1 score of 75%. From the perspective of frequency bands, within a single frequency band, the β band performed notably well in classification. However, the model constructed by integrating features from various frequency bands yielded the best classification performance. These comprehensive paradigms are expected to fill the current research gap in the application of EEG and provide new methodological perspectives for further studies. [Display omitted] [ABSTRACT FROM AUTHOR]

• Qualitative analysis on gain dynamics evolution in a narrow-linewidth fiber amplifier chain. • Revealing noise characteristics at low- and high-frequency regions in a fiber amplifier. • Effective optimization on RIN, FN and linewidth of single-frequency fiber laser amplifier. The relative intensity noise (RIN) and frequency noise (FN) of a single-frequency fiber laser (SFFL) are essential parameters that directly determine the sensitivity of high-precision optical metrology. Here, we report the gain-dynamics-dependent evolution of the RIN and FN in an SFFL Yb-fiber amplifier chain. Three types of single-mode Yb-doped fibers constructed with diverse mode-field diameters (MFD), core diameter, overlapping factor and doping concentrations were separately employed to achieve three SFFL amplifiers. The noise characteristics of the SFFL during the fiber amplification processes were investigated using contrast measurement curves of the RIN and FN. These results indicate that the amplifier-induced RIN and FN exhibit an iconic corner frequency of approximately 10 kHz. The relationships between the noise and signal input power exhibit opposite trends in the low- and high-frequency regions. In particular, the RIN curves of the noise power spectral density (PSD) reveal that a gain fiber with a larger overlapping factor can optimize the RIN. Moreover, higher doping concentration gain fiber can suppress the FN of the low-frequency region, realizing a narrower-linewidth SFFL. We believe that this study provides significant guidance for optimizing high-power, low-noise SFFL generation. [ABSTRACT FROM AUTHOR]

Photothermal therapy (PTT) is a promising strategy for antimicrobial therapy. However, the application of PTT to treat bacterial infections remains a challenge as the high temperature required for bacterial elimination can partly damage healthy tissues. Selecting the appropriate treatment temperature is therefore a key factor for PTT. In this work, we designed a near-infrared/pH dual stimuli-responsive activated procedural antibacterial system based on zeolitic imidazolate framework-8 (ZIF-8), which was bottom-up synthesized and utilized to encapsulate both Pd-Cu nanoalloy (PC) and the antibiotic amoxicillin (AMO). This procedural antibacterial therapy comprises chemotherapy (CT) and PTT. The former disrupts the bacterial cell wall by releasing AMO in an acidic environment, which depends on the sensitive response of ZIF-8 to pH value change. With the progression in time, the AMO release rate decreased gradually. The latter can then significantly stimulate drug release and further complete the antibacterial effect. This impactful attack consisted of two waves that constitute the procedural therapy for bacterial infection. Accordingly, the treatment temperature required for antibacterial therapy can be significantly lowered under this mode of treatment. This antibacterial system has a significant therapeutic effect on planktonic bacteria (G+/G−) and their biofilms and also has good biocompatibility; thus, it provides a promising strategy to develop an effective and safe treatment against bacterial infections. We have developed a near infrared/pH dual stimuli-responsive activated procedural antibacterial system that combines enhanced antibiotic delivery with photothermal therapy and has highly efficient antimicrobial activity. The antibacterial effect of this therapy was based on two mechanisms of action: chemotherapy, in which the bacterial cell wall was first destroyed, followed by photothermal therapy. After exposure to irradiation with an 808 nm laser, the inhibition rates were 99.8% and 99.1% for Staphylococcus aureus and Pseudomonas aeruginosa , respectively, and the clearance rates for their established biofilms were 75.3% and 74.8%, respectively. Thus, this procedural antibacterial therapy has shown great potentiality for use in the photothermal therapy of bacterial infectious diseases, including biofilm elimination. [Display omitted] [ABSTRACT FROM AUTHOR]

Considerable progress has been made in pattern recognition of surface electromyography (sEMG) with deep learning, bringing improvements to sEMG-based gesture classification. Current deep learning techniques are mainly based on convolutional neural networks (CNNs), recurrent neural networks (RNNs), and their hybrids. However, CNNs focus on spatial and local information, while RNNs are unparallelizable, and they suffer from gradient vanishing/exploding. Their hybrids often face problems of model complexity and high computational cost. Because sEMG signals have a sequential nature, motivated by the sequence modeling network Transformer and its self-attention mechanism, we propose a Transformer-based network, temporal depthwise convolutional Transformer (TDCT), for sparse sEMG recognition. With this network, higher recognition accuracy is achieved with fewer convolution parameters and a lower computational cost. Specifically, this network has parallel capability and can capture long-range features inside sEMG signals. We improve the locality and channel correlation capture of multi-head self-attention (MSA) for sEMG modeling by replacing the linear transformation with the proposed temporal depthwise convolution (TDC), which can reduce the convolution parameters and computations for feature learning performance. Four sEMG datasets, Ninapro DB1, DB2, DB5, and OYDB, are used for evaluations and comparisons. In the results, our model outperforms other methods, including Transformer-based networks, in most windows at recognizing the raw signals of sparse sEMG, thus achieving state-of-the-art classification accuracy. • Global features of sEMG signals can be captured better by our proposed network. • We improve local feature extraction with temporal convolutions in each sEMG channel. • We adopt depthwise separable convolution to improve channel correlation capture. • We reduce the parameters and computations through our proposed attention mechanism. [ABSTRACT FROM AUTHOR]

• The working domains of a hybrid heat pump for saturated steam is revealed. • The optimized performance of the hybrid system at different conditions is obtained. • A new evaluation criteria is defined to evaluate the hybrid heat pump system. • Comparison study with a typical heat pump system with/without rectifier is presented. • The application of the hybrid heat pump system is promoted. Absorption-compression heat pumps are especially suitable for high-temperature heat production, however, its performance at different conditions are highly influenced by the choice of ammonia-rich solution mass fraction and circulation ratio. This paper revealed the working domains of a hybrid absorption-compression heat pump for high-temperature (>130 °C) saturated steam production and obtained its optimized thermodynamic performance at different conditions. For saturated steam production, a supplied heat temperature up to 160 °C can be obtained using commercially available components with a thermal benefit compared to a gas boiler. For hot water or air production, the supplied temperature can be even higher. Moreover, a new heat coefficient of performance is proposed to evaluate the heat pump systems with both heat and power consumption. There are optimal heat coefficient of performance values for the circulation ratio and ammonia-rich solution mass fraction for the hybrid system. The results indicated that setting the ammonia-rich solution mass fraction less than 0.6 and the circulation ratio more than 0.7 is a better choice for the hybrid system in actual application. Finally, the hybrid heat pump system was used to improve the thermal performance of a saturated steam and power cogeneration system driven by an internal combustion engine. This work provides a useful guidance for the hybrid absorption-compression heat pump in actual application. [ABSTRACT FROM AUTHOR]

Highlights • Impact regime map of droplet impacting on heated silicon carbide surface is developed. • Droplet spreading dynamics and residence time during Leidenfrost state is analyzed. • Influence of surface roughness, wettability and surface material on the impact behaviors is analyzed. • Existing Leidenfrost temperature models are evaluated. Abstract Due to its superiority in suppressing hydrogen generation under severe accident conditions, silicon carbide (SiC) has been regarded as one of the promising candidates among the diverse accident tolerant fuel (ATF) claddings. Droplet impact experiments are conducted on preheated CVD-SiC surfaces with different roughness and the polished sintered-SiC and stainless-steel surface. The effects of surface roughness, contact angle and thermal properties on the impact behavior and cooling efficiency are discussed. The experiments are carried out in the range of 10 < We < 120 and T surf < 460 °C. The observed droplet impact phenomena on all the surfaces are categorized into five regimes, i.e. deposition, rebound with secondary atomization, breakup with secondary atomization, rebound and breakup. Deposition corresponds to nucleate boiling. Rebound and breakup are the hydrodynamic phenomena of film boiling. The rest two correspond to transition boiling. Droplet breakup can be induced thermally or mechanically in the transition boiling. Surface roughness can enhance droplet breakup both in the film and transition boiling. The small contact angle also promotes breakup. The thermal property of surfaces has little effect on the critical Weber number for droplet breakup, but affect the Leidenfrost point temperature (LPT) and CHF temperature significantly. The rupture of liquid film induced by roughness reduces the stagnant pressure beneath the droplet and lower the LPT. The droplet spreading dynamics are analyzed quantitatively, and developed an empirical model for droplet maximum spreading factor. It is found that the LPT model based on homogeneous nucleation mechanism coincides well with present experimental results. [ABSTRACT FROM AUTHOR]

Alternative splicing (AS) has been implicated in cell cycle regulation and cancer, but the underlying mechanisms are poorly understood. The poly(U)-binding splicing factor 60 (PUF60) is essential for embryonic development and is overexpressed in multiple types of cancer. Here, we report that PUF60 promotes mitotic cell cycle and lung cancer progression by controlling AS of the cell division cycle 25C (CDC25C). Systematic analysis of splicing factors deregulated in lung adenocarcinoma (LUAD) identifies that elevated copy number and expression of PUF60 correlate with poor prognosis. PUF60 depletion inhibits LUAD cell-cycle G2/M transition, cell proliferation, and tumor development. Mechanistically, PUF60 knockdown leads to exon skipping enriched in mitotic cell cycle genes, including CDC25C. Exon 3 skipping in the full-length CDC25C results in nonsense-mediated mRNA decay and a decrease of CDC25C protein, thereby inhibiting cell proliferation. This study establishes PUF60 as a cell cycle regulator and an oncogenic splicing factor in lung cancer. [Display omitted] • PUF60 acts as an oncogenic splicing factor and cell cycle regulator in lung cancer • PUF60 promotes lung cancer progression by regulating alternative splicing of mitotic genes • PUF60 depletion inhibits lung tumor development and reduces exon 3 inclusion in CDC25C • Exon 3 inclusion in CDC25C is critical for lung cancer cell proliferation Xu et al. identify the splicing factor PUF60 as a cell cycle regulator that promotes lung cancer development and progression. PUF60 depletion strongly inhibits mitotic cell cycle progression, cell proliferation, and tumor development of lung cancer, which is attributed by alternative splicing changes of cell cycle genes, particularly CDC25C. [ABSTRACT FROM AUTHOR]

In this research, an energy level difference graphic analysis method that describes the variation of the driving force for a thermodynamic process is proposed. This method is based on the average energy level difference, in which the contrastive analysis among energy transfer and conversion processes especially for off-design conditions is presented. The graphic analysis using this method is conducted on a combined cooling, heating and power (CCHP) system. At the design conditions, because the high energy level difference occurs in the combustor (COMB), the exergy destruction accounts for approximately 40% of the input fuel exergy, followed by the high-pressure generator (HPG). Moreover, this proposed method is introduced to evaluate the off-design performance of the CCHP system with the different operation method for the gas turbine. The energy level difference Δ A COMB under the inlet air throttling (IAT) operation method is decreased, which makes the less exergy destruction in the COMB compared with the reducing turbine inlet temperature (TIT) operation method. However, the opposite results are presented in the HPG. The proposed method may provide a new approach to reveal the energy-saving potential of the energy system. [ABSTRACT FROM AUTHOR]

An appropriate operation strategy is the requirement to obtain high-efficiency performance of a combined cooling, heating and power (CCHP) system. In this paper, the inlet air throttling (IAT) operation method for gas turbine combined with following the electric load (FEL), following the thermal load (FTL) and following the hybrid electric-thermal load (FHL) operation strategies are employed to analyze the primary energy consumption ( PEC ), carbon dioxide emission ( CDE ) and operation cost ( COST ) with respect to a CCHP system in Beijing, China. The matching between the different operation strategies and the energy demands of the reference building are analyzed to reveal the energy saving mechanism. The results indicate that the CCHP system is superior to the separate system on annual evaluation regardless of which operation strategy is used. Moreover, the economic performances of different operation strategies are evaluated based on the payback period ( PBP ). Finally, the sensitivity analyses of main component parameters and economic factors are presented for the PEC and PBP of the CCHP system, respectively. This study may provide a guidance to utilize the IAT operation method economically and efficiently. [ABSTRACT FROM AUTHOR]

This paper presents the exergy and exergoeconomic analyses of a typical combined cooling, heating and power (CCHP) system under off-design conditions. The exergoeconomic-related parameters and unit exergoeconomic cost of the flows are discussed using the exergy cost allocation method based on energy level (ECAEL). The absorption chiller is found to have an improved potential because of the highest relative cost difference and its continual increase with the decrease of the output power. According to the exergoeconomic factor analysis, the exergoeconomic performance of the turbine and combustor among all the components can be enhanced by decreasing the investment and destruction, respectively. Next, the unit energy costs of different products in the output power range (100–20%) including electricity, cooling and heating energy for users, are calculated. The results show that the electricity increases faster than that of other products from 0.537 to 1.077 Yuan/kWh. Finally, the sensitivity analyses for the unit energy cost of the products are presented with different influencing parameters, such as the natural gas price, service life and discount rate. This exergoeconomic analysis may provide guidance for evaluating the products in distributed energy systems for energy networks. [ABSTRACT FROM AUTHOR]

Thermodynamic and economic performance of the combined cooling, heating and power system (CCHP) is mainly affected by its configuration and operation strategy. In this paper, the reducing turbine inlet temperature (TIT) and inlet air throttling (IAT) control methods for gas turbines following the electric load (FEL) are used to analyze the primary energy consumption (PEC), operational cost (COST) and carbon dioxide emission (CDE) in a case of a CCHP system that satisfies the cooling, heating and electric demands of a five-star hotel in Beijing, China. The results indicate that the CCHP system with both TIT and IAT control methods has better off-design performance than separate system except for transition seasons. Since the more production of high-temperature flue gas, the IAT control method significantly reduces the fuel consumption of the auxiliary boiler to satisfy the thermal demand of the reference building, especially in hot summer and cold winter. In January, the IAT control method can decrease fuel consumption by 7.53% compared with TIT control method. Moreover, it is found that improved energy saving performance and decreased operation cost and carbon dioxide emission of the CCHP system are presented with the IAT control method at the annual performance. Finally, the sensitivity analysis of the electric price and gas price is presented for the operation cost and shows that the gas price is the most sensitive variables for the operation cost of the CCHP system. [ABSTRACT FROM AUTHOR]

A feasibility study was conducted on using solar energy in a conventional tri-generation system for sewage treatment plant application. Generally conventional CHP/CCHP systems can improve the biogas utilization efficiency, however, the waste heat from the power engines is limited for the digester thermal insulation most time in some colder areas, and the additional natural gas is consumed for supplement. This paper proposes a biogas and solar energy-assisted tri-generation system that upgrades the caloric value of biogas before combustion by introducing a thermochemical conversion process. The hourly dynamic energy performances of the proposed and reference systems were simulated by the established mathematic models under Tibet Lhasa weather data. Using solar energy not only reduces the dependence on the external fossil fuel, but also increase the output electric power and cooling energy. The saved natural gas in the whole year can reach 142,757 Nm 3 . This study may provide a new way to efficiently use the solar energy to improve the energy performance of tri-generation systems. [ABSTRACT FROM AUTHOR]

The part-load performance of combined cooling, heating and power (CCHP) system based on exergy and energy level graphic analysis under compressor inlet air throttling (IAT) operating strategy is presented in this paper. The results show that the combustor (COMB) is found to have the largest exergy destruction followed by high-pressure generator (HPG). Compared with the reducing turbine inlet temperature (TIT) operating strategy, the exergy destruction of COMB is decreased under IAT operating strategy; however, the opposite result is presented in HPG. A new graphic analysis based on energy level difference is proposed to indicate the potential to enhance the thermodynamics performance of the components under different operating strategies. The decrease of the energy level difference in the COMB and HPG is a most positive way to decrease the exergy destruction with IAT and TIT operation strategies. [ABSTRACT FROM AUTHOR]

This paper analyzes a solar assisted combined cooling, heating and power (SCCHP) system which supplies electricity, cooling and heat, with internal energy recovery and thermochemical upgrading. The proposed system consists of a chemically recuperated gas turbine cycle, an exhaust heat-driven absorption chiller and a heat exchanger, in which the reformer upgrades the absorbed turbine exhaust heat and solar heat into produced syngas chemical exergy. The system performance is analyzed and compared with a regular CCHP system without solar assistance, and a parameter sensitivity analysis is conducted to investigate the influence of the steam addition ratio. The system exhibits enhanced specific power generation and efficiency, and it saves depletable fossil fuel and commensurately reduces CO 2 emissions. The system exergy efficiency reaches 37%; a fossil fuel saving of 30.4% is attainable with a solar thermal share of 26%; and the reduction of fossil fuel use and improved system performance result in a commensurate 33% reduction of CO 2 emission as compared with the conventional CCHP system with the same technology but without solar assistance. [ABSTRACT FROM AUTHOR]

The off-design performance of a combined cooling heating and power (CCHP) system is of great importance and is affected by the system configuration and operating strategy. This paper proposes an alternative operating strategy called flue gas reinjecting (FGR) for a CCHP system consisting of a small-scale gas turbine, a double-effect absorption chiller and a hot water exchanger. The FGR operating strategy elevates the compressor inlet temperature by reinjecting a portion of the flue gas into the ambient air, which seems to contradict the well-proven concept of gas turbine inlet air cooling. In contrast, improving inlet air temperature cannot obviously influence the off-design performance of the gas turbine, and more high-temperature flue gas is produced in the gas turbine, which leads to more cooling and heating output in the absorption chiller and hot water exchanger, respectively. To extend the power output range (100–20%), reducing the turbine inlet temperature (TIT) operating strategy is introduced as an auxiliary means. The off-design performance of the CCHP system is investigated under the combined FGR and TIT operating strategy and independent TIT operating strategy. It is found that improved total efficiency and energy saving performance of the CCHP system are presented with the combined operating strategy at partial load. At a load rate of 50% (876 kW), the fuel energy saving ratio (FESR) increases from 20.52% to 22.96% as the temperature of the inlet air is increased from 25 to 45 °C using the combined operation strategy. The exhaust gas reinjection reduces the excess air resulting in inhibition of the formation of NO X in the combustor. Moreover, using the proposed operating strategy contributes to promoting more effective utilization of low-temperature heat and the direct blending of two fluids reduces heat and pressure losses emanating from the heat exchanger. This study may provide a new operating strategy for small-scale gas turbines to improve the off-design performance of CCHP systems. [ABSTRACT FROM AUTHOR]