•The impact of product attributes on customer satisfaction is measured.•The study combines natural language processing with explanatory econometric modeling.•Customer satisfaction is significantly ...affected by several product attributes.•Satisfaction is affected by different attributes when the product price changes.•Satisfaction level for certain attributes largely depends on customers’ perception.
Online reviews are an important information source for companies analysing users’ demands. We conducted a study of online reviews to measure how product attributes impact customer satisfaction. First, we attempted to infer through sentiment analysis whether a customer is satisfied with a purchase according to their review. Second, a logistic regression model was developed to estimate the impact of various product properties on customer satisfaction scores. Our estimates indicated that customer satisfaction is influenced by drainage mode, loading type, frequency conversion, type, display, colour, and capacity. We further investigate the impact of price and find that customers who buy cheap products should be treated differently from purchasers of expensive items because the relevance of design features on their satisfaction is different. Additionally, we observed that although customers are concerned about noise, perceived noise is not consistent with actual noise levels. We analysed specific reviews and then obtained more detailed information on customer attitudes.
•Synthesis of the HKUST-1 with mesoporous structure.•Exploration of the new application of MOFs materials in uranium removal.•Development of a high-efficiency adsorbent for uranium.
This paper ...reports on the efficient adsorption for uranium by metal-organic frameworks (MOFs) HKUST-1 from aqueous solution. The structure of the prepared HKUST-1 was characterized by X-ray diffraction (XRD), Scanning electron microscope (SEM), Transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FTIR) and nitrogen adsorption/desorption analysis. The influences of different experimental parameters were studied, such as initial solution pH, adsorbent dosage, adsorption time, temperature and various concentrations of uranium uptake. The thermodynamic parameters including Gibbs free energy (ΔG0), standard enthalpy change (ΔH0) and standard entropy change (ΔS0) for the process were calculated using the Langmuir constants. The results showed that the equilibrium data fitted well to Langmuir model in the studied range of uranium concentration (10mg/L–800mg/L) and temperature (298K–318K), and the HKUST-1 exhibited the highest uptake for uranium at 318K, at the initial solution pH value of 6 and at the initial uranium concentration of 800mg/L. The thermodynamics of uranium/HKUST-1 system indicated the spontaneous and endothermic nature of the process. And the kinetics of the adsorption process followed the pseudo-second-order kinetics model.
As a simple, fast and effective 3D printing method, direct-ink-writing (DIW) has potential applications in repairing the circuit board in orbit, printing the wearable devices for the astronaut, and ...producing the solar cells for the energy supply in space. To expand the DIW technology to space, we designed the colloidal material box (CMB) as the prototype printer of DIW and verified its applicability in the Chinese SJ-10 satellite. The colloidal suspensions was adopted as a diluted ink model to investigate two key processes of DIW under microgravity environment: manipulation of the droplet and formation of the patterns. We have showed the dynamics of the droplet, which would determine the size of the features, could be controlled through tuning the wettability of the needles and the solid surface. Compared to the ground, the “coffee ring” effect was weakened for the drying patterns because of strong interfacial effect under weightless conditions. We have found that fast evaporation could assist for fabricating more uniform and ordered structures.
Abstract
China and ASEAN have strong ties and have become each other’s largest trading partners. This article uses the gravity model and a novel method of analysis, based on massive event data ...provided by the Global Database of Events, Language, and Tone, to empirically analyse the impact of fluctuations in bilateral relations between China and ASEAN on bilateral trade from January 2001 to December 2020. An analysis of 1,204,126 event records concluded that the improvement of bilateral relations was beneficial for trade between China and ASEAN countries. China’s export trade was more easily influenced by bilateral relations than its import trade. Compared to the one-way behavioural attitude of ASEAN countries towards China, China’s one-way reaction to ASEAN countries had a greater impact on bilateral trade. China’s trade dependence level with most ASEAN countries maintains a trend of steady growth, and trade relations show a positive trend. Therefore, China and ASEAN should maintain stable political ties, enhance mutual understanding, strengthen economic and political connectivity, take adequate measures to promote mutual trust, continue optimizing cooperation models, and promote high-quality and high-level sustainable development across the region.
In order to achieve strong wide band acoustic absorption under high hydrostatic pressure, an interpenetrating network structure is introduced into the locally resonant phononic crystal to fabricate a ...type of phononic composite material called "phononic glass." Underwater acoustic absorption coefficient measurements show that the material owns high underwater sound absorption coefficients over 0.9 in 12-30 kHz. Moreover, the quasi-static compressive behavior shows that the phononic glass has a compressive strength over 5 MPa which is crucial for underwater applications.
Cancer is a common comorbidity of diabetic patients; however, little is known about the effects that antidiabetic drugs have on tumors. We discovered that common classes of drugs used in type 2 ...diabetes mellitus, the hypoglycemic dipeptidyl peptidase-4 inhibitors (DPP-4i) saxagliptin and sitagliptin, as well as the antineuropathic α-lipoic acid (ALA), do not increase tumor incidence but increase the risk of metastasis of existing tumors. Specifically, these drugs induce prolonged activation of the nuclear factor E2-related factor 2 (NRF2)-mediated antioxidant response through inhibition of KEAP1-C151-dependent ubiquitination and subsequent degradation of NRF2, resulting in up-regulated expression of metastasis-associated proteins, increased cancer cell migration, and promotion of metastasis in xenograft mouse models. Accordingly, knockdown of NRF2 attenuated naturally occurring and DPP-4i-induced tumor metastasis, whereas NRF2 activation accelerated metastasis. Furthermore, in human liver cancer tissue samples, increased NRF2 expression correlated with metastasis. Our findings suggest that antioxidants that activate NRF2 signaling may need to be administered with caution in cancer patients, such as diabetic patients with cancer. Moreover, NRF2 may be a potential biomarker and therapeutic target for tumor metastasis.
When a liquid is supercooled towards the glass transition, its dynamics drastically slows down, whereas its static structure remains relatively unchanged. Finding a structural signature of the ...dynamic slowing down is a major challenge, yet it is often too subtle to be uncovered. Here we discover the structural signatures for both translational and rotational dynamics in monolayers of colloidal ellipsoids by video microscopy experiments and computer simulations. The correlation lengths of the dynamic slowest-moving clusters, the static glassy clusters, the static local structural entropy and the dynamic heterogeneity follow the same power-law divergence, suggesting that the kinetic slowing down is caused by a decrease in the structural entropy and an increase in the size of the glassy cluster. Ellipsoids with different aspect ratios exhibit single- or double-step glass transitions with distinct dynamic heterogeneities. These findings demonstrate that the particle shape anisotropy has important effects on the structure and dynamics of the glass.
Background. Adipokines are reported to participate in many common pathologic processes of glucose dysregulation, such as insulin resistance, β-cell dysfunction, and chronic inflammation. Objective. ...To detect the concentrations of plasma asprosin in subjects with impaired glucose regulation (IGR) and newly diagnosed type 2 diabetes (nT2DM) and its relationship to parameters of glucose and lipid metabolism, insulin resistance, and pancreatic β-cell function. Methods. 143 eligible participants were included and were divided into three groups including normal glucose regulation (NGR, n=52), IGR (n=40), and nT2DM group (n=51). The intravenous glucose tolerance test (IVGTT) and clinical and biochemical parameters were measured in all participants. Results. Plasma asprosin levels were higher in IGR (82.40 ± 91.06 ng/mL, P<0.001) and nT2DM (73.25 ± 91.69 ng/mL, P<0.001) groups compared with those in the NGR (16.22 ± 9.27 ng/mL) group, especially in IGR subjects. Correlation analysis showed that plasma asprosin levels were positively correlated with waist circumference (Wc), fasting plasma glucose (FPG), postchallenge plasma glucose (2hPG), HbA1c, triglyceride (TG), and homeostasis model assessment for insulin resistance (HOMA-IR) and negatively correlated with homeostasis model assessment for β-cell function (HOMA-β), area under the curve of the first-phase (0–10 min) insulin secretion (AUC), acute insulin response (AIR), and glucose disposition index (GDI) (all P<0.05). Multiple logistical regression analyses revealed that plasma asprosin concentrations were significantly correlated with IGR and nT2DM after controlling for age, sex, BMI, and WHR. Conclusions. Circulating asprosin might be a predictor of early diagnosis in DM and might be a potential therapeutic target for prediabetes and T2DM.
Elastic metamaterials have promising applications in wave control and vibration isolation, due to their extraordinary characteristics, e.g., negative Poisson ratio, band gaps, effective negative mass ...density and effective negative modulus. How to develop new functional metamaterials using a special structure has always been a hot topic in this field. In this study, a three-dimensional (3D) star structure is designed to construct metamaterials with both negative static and dynamic properties. The results show that the 3D star structure formed a wide band gap at lower frequency and had a negative Poisson's ratio. Different from conventional acoustic metamaterials, the main physical mechanism behind the low-frequency band gap of the 3D star structure is the resonance mode formed by the bending deformation of each rib plate, which made it easier to achieve effective isolation of low-frequency elastic waves with a low mass density. In addition, many structural parameters of the 3D star structure can be modulated to effectively adjust the band gap frequency by changing the angle between the concave nodes and aspect ratio. This study provides a new way to design the 3D acoustic metamaterials and develop the lightweight vibration isolation devices.
Metal-organic frameworks (MOFs) exhibiting high surface area and tunable pore size own broad application prospects. Compared with existing MOFs, MOF-5 Zn4O(bdc)3 is a promising hydrogen storage ...material due to high H2 uptake capacity and thermostability. However, further wider applications of MOF-5 have been limited because atmospheric moisture levels cause MOF-5 instability. MOF-5 and multi-walled carbon nanotubes (MWCNTs) hybrid composite (denoted MOFMC) can enhance stability toward ambient moisture and improve hydrogen storage capacity. In this paper, the MOFMC, which has an interpenetrated structure with high mesoporosity, was synthesized. The MOFMC is denoted as Int-MOFMC-meso. It stored 2.02 wt% H2 at 77 K under 1 bar, which is higher than the MOF-5 with similar structure and the earlier reported MOFMC material. Moreover, the Int-MOFMC-meso can also show more excellent performance of thermostability and moisture stability than the MOF-5 with similar structure.
•The Int-MOFMC-meso has an interpenetrated structure with high mesoporosity.•The Int-MOFMC-meso can store 2.02 wt% H2 at 77 K under 1 bar.•The Int-MOFMC-meso shows excellent performance of stability.
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