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Within the appraisal system and the metadiscourse model, we examine engineering writers' evaluative behavior imprinted in research article introductions. Using a combination of in-house script and manual annotation, we explore lexical frequencies, semantic prosodies, and rhetoric constructs in the introductory sections of 100 most cited research articles spreading evenly across ten engineering sub-disciplines. The findings show that engineering research writers tend to provide factual rather than factional evaluations. The evaluative patterns and paces, however, vary due to the writers' step choices in each move. Despite the ubiquitous positivity bias suggested by the number of positive lexis and sentences, our study finds negative evaluations occur and oscillate between the three moves in the introductions, and often present with purposeful choices of technical details. Meanwhile, the use of attitudinal markers with strong negative values indicates that engineering writers express their criticality rather directly with little concessions and even less dramatization. • Evaluative patterns and paces vary due to the writers' step choices. • Negative evaluations occur and oscillate between the three moves in the introductions. • Engineering writers express their criticality rather directly. [ABSTRACT FROM AUTHOR]

We establish a conceptual model of the graphene-assisted near-field electroluminescent refrigerator (GANER), which is composed of an emitter and a receiver. The two basic components are formed by a homojunction structure using III–V group semiconductors as materials. The cooling rate density (CRD) and coefficient of performance (COP) of the GANER are derived based on fluctuation electrodynamics and thermodynamics. The electrical–optical–thermal coupling properties and parametric optimum designs of the GANER and the near-field electroluminescent refrigerator (NER) are studied. The performances of the GANER and the NER are compared. By making tradeoff between the CRD and the COP, the selective criteria of several key parameters are provided. The effects of graphene’s chemical potential and finite-rate heat transfer between the refrigerator and the environment on the optimum performances of the GANER are discussed. It is found that for an arbitrary value of the chemical potential, the performance of the GANER is superior to that of the NER. The advantages of the GANER are more prominent for a large chemical potential. The results obtained here may provide some guidance for optimally designing solid-state refrigerators. [ABSTRACT FROM AUTHOR]

The novel cycle model of a three-quantum-dot cooler, which possesses three Fermi reservoirs connected by three quantum dots to form a ring, is proposed. The roles of the properties of thermal reservoirs and the energy levels of quantum dots in determining the thermodynamic characteristics of the cooler are revealed. Quantitative analyses of the necessary conditions of cooling in the cases of particle flows moving clockwise or counterclockwise in the ring are obtained. The energy levels of quantum dots and the chemical potentials of heat reservoirs are selected optimally so that the cooler attains its maximum cooling rate. The effects of the chemical potentials of heat reservoirs on the systemic performance are analyzed. The optimal values of other parameters at the maximum cooling rate are calculated numerically, and the optimal selection criteria of main parameters are provided. All these results obtained here reveal a useful approach toward high-performance quantum refrigerators in multi-terminal nanoscale systems. This work establishes a quantum cooler considering three Fermi reservoirs connected by three quantum dots to form a ring. The necessary conditions of cooling in the cases of electron flows moving clockwise or counterclockwise in the ring are obtained, and the effects of characteristic parameters at the maximum cooling rate are discussed. The proposed model can open a new avenue for building practical coolers where thermal manipulation at micro-level is required. [ABSTRACT FROM AUTHOR]

A neoteric model of the solar-driven integrated device mainly composed of a thermionic generator (TIG) with a graphene-based anode and a thermophotovoltaic cell is presented, where the major irreversible losses inside and outside the system are considered. The analytical expressions for the power output and efficiency of two subsystems and the integrated device are derived. The temperatures of the emitter and collector are determined through heat balance equations. The effects of the voltage outputs of the generator and cell, area ratio of the absorber to the emitter, bandgap energy of the cell, and solar concentration factor on the systemic performance are evaluated. Several main parameters are optimized and parametric selection criteria are provided. The maximum efficiencies of the integrated device operated at different conditions are calculated. For example, under 1000 solar concentration, the efficiency of the integrated device attains 45.23%, which is obviously higher than that of a single solar-driven TIG (STIG) or other existing hybrid systems with a traditional TIG. It is found that replacing metallic anode by graphene anode and integrating a photovoltaic cell into the STIG largely enhance the conversion efficiency of solar energy. [ABSTRACT FROM AUTHOR]

Liraglutide, as a glucagon‑like peptide‑1 analogue, is used to treat type 2 diabetes mellitus and obesity. Previous findings have demonstrated the effects of liraglutide on adipogenesis; however, the underlying mechanism involved in this process remains to be elucidated. In the present study, to certify the effect of liraglutide on adipogenesis and explore the possible underlying mechanism involved in this process, preadipocyte 3T3‑L1 cells were cultured in adipocyte‑inducing medium and treated with liraglutide. Subsequently, the expression levels of the master transcription factors and adipocyte‑specific genes were measured by reverse transcription‑quantitative polymerase chain reaction and immunoblotting analysis. Lipid droplet production was detected by Oil red O staining. Cell proliferation was determined by a Cell Counting Kit-8 assay and cell immunofluorescence for Ki67, and apoptosis was assessed by flow cytometry. Next, the expression levels of the core components in the Hippo‑yes‑associated protein (YAP) signaling pathway as well as YAP‑specific target genes were measured. Finally, short interfering RNAs of mammalian ste20 kinase 1/2 (MST1/2), a key protein kinase in the Hippo‑YAP pathway, were used to determine whether liraglutide regulated adipogenic differentiation via the Hippo‑YAP pathway. It was demonstrated that liraglutide promoted adipogenic differentiation, suppressed proliferation, did not affect apoptosis of 3T3‑L1 cells and activated the Hippo‑YAP signaling pathway at the initial stage of adipogenesis. Silencing of MST1 counteracted the effect of increasing adipogenesis by liraglutide. These results suggested that liraglutide may activate the Hippo‑YAP signaling pathway leading to the inhibition of proliferation of preadipocyte 3T3‑L1 cells, and result in cells achieving transformation into mature adipocytes sooner. Taken together, the results of the present study may expand knowledge of the underlying mechanism of liraglutide facilitating adipogenesis, and may contribute to the development of GLP‑1 receptor agonists for weight loss and increased insulin sensitivity. [ABSTRACT FROM AUTHOR]

A self-reliant quantum cooler without an external control is proposed. To understand the thermal transport properties of the quantum system interacting with the baths described by the grand canonical ensemble, a two-level system with a single energy transport channel and a two-level coupled system with multi-channels are established. By considering the temperature dependence of the chemical potentials of the ultracold atom baths, the steady-state heat flows, particle currents, and entropy productions of these systems are derived. Results show that a steady heat current flows against the thermal bias for a nonequilibrium system coupled with ultracold quantum gases and the cooling rate can be enhanced by quantum coherence. • A quantum cooler is operated between two ultracold atom baths. • Ultracold atom baths are described by the grand canonical ensemble. • The self-contained cooling may be realized without an external control. • The relations between the cooling rate and other parameters are revealed. • The quantum coherence can enhance the cooling rate. [ABSTRACT FROM AUTHOR]

We proposed the finite-time cycle model of a measurement-based quantum cooler, where the invasive measurement provides the power to drive the cooling cycle. Such a cooler may be regarded as an alternative thought experiment of Maxwell's demon. The measurement-feedback information is capable of moving heat from the cold to hot bath without any work input and even making the maximum coefficient of performance larger than the Carnot limit. The causes that this seemingly paradoxical result does not violate the laws of thermodynamics can be clearly explained through the derivation of a generalized Clausius inequality including the mutual information. [ABSTRACT FROM AUTHOR]

• A concentrated solar spectrum photovoltaic-thermoradative coupled system is proposed. • Maximum efficiency and corresponding values of other parameters are calculated. • Optimum selection criteria of several main parameters are provided. • The proposed system can obtain a large efficiency under low solar concentration. • Optimal performances obtained here are superior to those of other related systems. Solar photovoltaic cells are widely used in many aspects, but a mass of solar energy cannot be utilized, resulting in much waste heat being dissipated into the environment, which limits the performance of photovoltaic cells. To improve the utilization of solar energy, a novel model of the concentrated solar spectrum photovoltaic-thermoradiative coupled system is established, where main irreversible losses in the system are considered. Expressions for the power outputs and efficiencies of two subsystems and coupled system are derived. The effects of the voltage outputs and bandgap energies of two cells, area ratios of different units, and the concentration factor on the performance of the coupled system are investigated in detail. The maximum efficiency and corresponding power output density of the coupled system are numerically calculated. The optimal selection criteria of the main parameters affecting the systemic performance are provided. Two subsystems are optimally matched. The performance characteristics of the coupled system are revealed. Compared with the photovoltaic cell and thermoradiative cell alone, the proposed system has a large efficiency enhancement. Compared with other photovoltaic-based coupled systems, the proposed system can be operated at low solar concentration and the maximum efficiency can attain 44.91%, which has a significant efficiency improvement. [ABSTRACT FROM AUTHOR]

Based on nanoelectronic devices that can act as power generators or refrigerators, the relations between the entropy production rate and the thermal efficiency or coefficient of performance are obtained for two types of electron filters. It is found that the decrease of the entropy production rate does not always guarantee the increase of the thermal efficiency or coefficient of performance, indicating that the state of the minimum entropy production rate does not correspond to that of the maximum thermal efficiency or coefficient of performance in these electronic devices. It implies the fact that different from the thermal efficiency or coefficient of performance, the entropy production rate is not a good objective function for optimizing the performance of electronic devices. However, entropy analyses will be helpful to deeply understanding the thermodynamic properties of electronic devices. These results obtained here will provide a feasible scheme to further optimize and improve the performances of electronic devices. • Two models of electronic devices as heat engines or refrigerators are set up. • The effects of irreversible electron transfer processes are considered. • The maximum efficiency and coefficient of performance of devices are calculated. • The relations between entropy production rate and other parameters are revealed. • It is found that the entropy production rate is not a good objective function. [ABSTRACT FROM AUTHOR]

Hibernation, a survival strategy in mammals for extreme climates, induces physiological phenomena such as ischemia–reperfusion and metabolic shifts that hold great potential for advancements in modern medicine. Despite this, the molecular mechanisms underpinning hibernation remain largely unclear. This study used RNA‐seq and Iso‐seq techniques to investigate the changes in liver transcriptome expression of Rhinolophus pusillus during hibernation and active periods, as well as under different microhabitat temperatures. We identified 11 457 differentially expressed genes during hibernation and active periods, of which 395 showed significant differential expression. Genes associated with fatty acid catabolism were significantly upregulated during hibernation, whereas genes related to carbohydrate metabolism and glycogen synthesis were downregulated. Conversely, immune‐related genes displayed differential expression patterns: genes tied to innate immunity were significantly upregulated, while those linked to adaptive immunity and inflammatory response were downregulated. The analysis of transcriptomic data obtained from different microhabitat temperatures revealed that R. pusillus exhibited an upregulation of genes associated with lipid metabolism in lower microhabitat temperature. This upregulation facilitated an enhanced utilization rate of triglyceride, ultimately resulting in increased energy provision for the organism. Additionally, R. pusillus upregulated gluconeogenesis‐related genes regardless of the microhabitat temperature, demonstrating the importance of maintaining blood glucose levels during hibernation. Our transcriptomic data reveal that these changes in liver gene expression optimize energy allocation during hibernation, suggesting that liver tissue adaptively responds to the inherent stress of its function during hibernation. This study sheds light on the role of differential gene expression in promoting more efficient energy allocation during hibernation. It contributes to our understanding of how liver tissue adapts to the stressors associated with this state. [ABSTRACT FROM AUTHOR]

Liver kinase B1 (LKB1) plays an important role in adipogenesis, but the underlying molecular mechanism is poorly understood. Here, we explored the functional relationship between LKB1 and the mammalian target of rapamycin (mTOR) in regulating adipogenesis in rats and preadipocytes. We found that LKB1 and the adenosine 5′-monophosphate (AMP)-activated protein kinase (AMPK) cascade are impaired in the white adipose tissue (WAT) of diet-induced obesity (DIO) and diet-resistant (DR) rats when compared with chow-fed (CF) rats. While DIO activated the mTOR pathway in WAT and led to a more fat mass gain, DR maintained the normal activity of the mTOR pathway and normal weight and percentage of fat mass. We further constructed overexpressed LKB1 (OE) and silenced LKB1 (Si) 3T3-L1 preadipocytes monoclonal cell lines. In the OE cell line, the mTOR pathway was inactivated, and intracellular lipid content was reduced during differentiation. This effect could be reversed by AMPK inhibition. Conversely, in the Si cell line, the mTOR pathway was activated and intracellular lipid content increased. This effect could be reversed by rapamycin, an inhibitor of mTOR. Our results suggest that mTOR mediates the effect of LKB1 on adipogenesis, and normal activity of mTOR in DR rats interferes with the effect of LKB1 in WAT. [ABSTRACT FROM AUTHOR]