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Lithium-ion batteries (LIBs) subjected to external heat may be prone to failure and cause catastrophic safety issues. In this work, experiments were conducted to investigate the influence of discharge current on the thermal runaway process under thermal abuse. The calibrated external heat source (20 W) and discharge currents from 1 to 6 A were employed to match the thermal abuse conditions in an operational state. The results indicated that the key parameters during the failure process, such as the total mass loss, the onset temperatures of safety venting and thermal runaway, and the peak temperature, are ultimately determined by the capacity inside the battery, and the discharge current can hardly change it. However, discharge currents can produce extra energy to accelerate the thermal runaway process. Compared with the battery in an open circuit, the onset time of thermal runaway was reduced by 7.4% at 6 A discharge. To quantify the effect of discharge current, the total heat generation by discharge current was calculated. The results show that a heat generation of 1.6 kJ was produced when the battery was discharged at 6 A, which could heat the cell to 34 °C (neglect of heat loss). This study simulates the failure process of the LIB in the operational state, which is expected to help the safety application of LIB and improve the reliability of the battery management system.

With the development of integrated energy systems (IES), the traditional demand response technologies for single energy that do not take customer satisfaction into account have been unable to meet actual needs. Therefore, it is urgent to study the integrated demand response (IDR) technology for integrated energy, which considers consumers’ willingness to participate in IDR. This paper proposes an energy management optimization method for community IES based on user dominated demand side response (UDDSR). Firstly, the responsive power loads and thermal loads are modeled, and aggregated using UDDSR bidding optimization. Next, the community IES is modeled and an aggregated building thermal model is introduced to measure the temperature requirements of the entire community of users for heating. Then, a day-ahead scheduling model is proposed to realize the energy management optimization. Finally, a penalty mechanism is introduced to punish the participants causing imbalance response against the day-ahead IDR bids, and the conditional value-at-risk (CVaR) theory is introduced to enhance the robustness of the scheduling model under different prediction accuracies. The case study demonstrates that the proposed method can reduce the operating cost of the community under the premise of fully considering users’ willingness, and can complete the IDR request initiated by the power grid operator or the dispatching department.

We study a planar Josephson junction under an applied DC voltage bias in the presence of an in-plane magnetic field. Upon tuning the bias voltage across the junction V_{J}, the two ends of the junction are shown to simultaneously host both zero and π Majorana modes. These modes can be probed using either a scanning-tunneling-microscopy measurement or through resonant Andreev tunneling from a lead coupled to the junction. While these modes are mostly bound to the junction's ends, they can hybridize with the bulk by absorbing or emitting photons. We analyze this process both numerically and analytically, demonstrating that it can become negligible under typical experimental conditions. Transport signatures of the zero and π Majorana states are shown to be robust to moderate disorder.

In this paper, a new method to regulate the correlated color temperature (CCT) of white light-emitting diodes (LEDs) is proposed for the single-chip packaging structure, in which the blue light distribution emitted from the chip in the red/yellow phosphor layer was modulated through changing the paraffin-polydimethylsiloxane (PDMS) film transparence and haze. The results show that the transmittance of the paraffin-PDMS film can be modulated from 49.76% to 97.64%, while the haze of that ranges from 88.19% to 63.10%. When the thickness of paraffin-PDMS film is 0.6 mm, and the paraffin-PDMS film concentration is 30 wt%, the CCT of white LED decreases from 15177 K to 3615 K with the increase of thermal load in the paraffin-PDMS film. The modulating range of its CCT reaches 11562 K. The maximum CCT variation at the same test condition is only 536 K in the repeated experiments within one week.

Shape memory polymers(SMPs) are a class of functional "smart" materials that have shown bright prospects in the area of biomedical applications. The novel smart materials with multifunction of biodegradability and biocompatibility can be designed based on their general principle, composition and structure. In this review, the latest process of three typical biodegradable SMPs(poly(lactide acide), poly(ε-caprolactone), polyurethane) was summarized. These three SMPs were classified in different structures and discussed, and shape-memory mechanism, recovery rate and fixed rate, response speed was analysed in detail, also, some biomedical applications were presented. Finally, the future development and applications of SMPs are prospected: two-way SMPs and body temperature induced SMPs will be the focus attension by researchers.

Abstract Non-thermal atmospheric pressure plasma has been proposed as a new therapeutic tool for cancer treatment. Recently, plasma-activated medium (PAM) has been widely studied in various cancer types. However, there are only few reports demonstrating the anti-tumour effects of PAM in an animal model reflecting pathological conditions and the accompanying mechanism. Here we investigated the inhibitory effect of PAM on the metastasis of ovarian cancer ES2 cells in vitro and in vivo. We demonstrated that ES2 cell migration, invasion and adhesion were suppressed by PAM at a certain PAM dilution ratio, whereas cell viability remained unaffected. In an in vivo mouse model of intraperitoneal metastasis, PAM inhibited peritoneal dissemination of ES2 cells, resulting in prolonged survival. Moreover, we assessed the molecular mechanism and found that MMP-9 was decreased by PAM. On further investigation, we also found that PAM prevented the activation of the MAPK pathway by inhibiting the phosphorylation of JNK1/2 and p38 MAPK. These findings indicate that PAM inhibits the metastasis of ovarian cancer cells through reduction of MMP-9 secretion, which is critical for cancer cell motility. Our findings suggest that PAM intraperitoneal therapy may be a promising treatment option for ovarian cancer.

We sequenced the complete plastid genome of Anomodon attenuatus. The genome size is 125,320 bp with two inverted repeat regions of 9,948 bp separated by a large single-copy region of 86,847 bp and a small single-copy region of 18,578 bp. It encodes 114 unique genes including 80 protein-coding genes, 30 tRNA genes and 4 rRNAgenes. The overall GC content is 29.5%, with 26.9, 26.5, and 43.9% in LSC, SSC, IR regions, respectively. 139 SSRs were identified in the genome. Phylogenetic anlysis showed that the position of A.attenuatus is closely related to S.uncinata, another pleurocarpous moss.

Abstract In this short note, we present some trace inequalities for matrix means. Our results are generalizations of the ones shown by Bhatia, Lim, and Yamazaki.

Objective: To compare the bifomechanical advantages and disadvantages of different internal fixation methods for the treatment of Pauwels type III femoral neck fractures. Methods: 4 internal fixations were developed to treat Pauwels type III femoral neck fracture finite element models: a: the “F” shaped cannulated screw model, b: the traditional cannulated screw model, c: the “F” shaped cannulated screw coupled with medial plate model, d: the traditional cannulated screw coupled with medial plate. Under the same conditions, the 4 internal fixations and femur of von Mises stress and displacement distribution were studied. Results: The most significant displacement of all models occurred at the femoral head. The maximum displacement of the femoral heads included: a: 1.53 mm, b: 1.73 mm, c: 1.18 mm and d: 1.34 mm. The von Mises peak stresses of the femoral calcar area in different models were: a: 115.2 MPa, b: 143.5 MPa, c: 107.8 MPa and d: 120.5 MPa. The peak stresses of the four internal fixation models included: a: 318.0 MPa, b: 360.9 MPa, c: 468.8 MPa and d: 771.5 MPa. Conclusion: The “F” shaped cannulated screw technique is capable of eliminating the torsional stress and shear stress while maintaining the axial compressive stress at the fracture end. Besides, the medial support plate can effectively resist the shearing force of the Pauwels III femoral neck fracture and create an excellent mechanical environment for fracture healing. Thus, for the Pauwels III femoral neck fracture, the use of “F” shaped cannulated screws combined with medial plate internal fixation are recommended.

In this paper, we first present a generalization of the Cauchy-Schwarz inequality. As an application of our result, we obtain a new sufficient condition for the stability of a class of nonlinear impulsive control systems. We end up this note with a numerical example which shows the effectiveness of our method.

With the rapid development of large-scale complex networks and proliferation of various social network applications, the amount of network traffic data generated is increasing tremendously, and efficient anomaly detection on those massive network traffic data is crucial to many network applications, such as malware detection, load balancing, network intrusion detection. Although there are many methods around for network traffic anomaly detection, they are all designed for single machine, failing to deal with the case that the network traffic data are so large that it is prohibitive for a single computer to store and process the data. To solve these problems, we propose a parallel algorithm based on Isolation Forest and Spark for network traffic anomaly detection. We combine the advantages of Isolation Forest algorithm in network traffic anomaly detection and big data processing capability of Spark technology. Meanwhile, we apply the idea of parallelization to the process of modeling and evaluation. In the calculation process, by assigning tasks to multiple compute nodes, Isolation Forest and Spark can efficiently perform anomaly detection and evaluation process. By this way, we can also solve the problem of computation bottleneck on single machine. Extensive experiments on real world datasets show that our Isolation Forest and Spark is efficient and scales well for anomaly detection on large network traffic data.

Summary: Background: Identification of windows of heightened vulnerability to environmental factors has substantial public health implications. Prenatal exposure to vanadium has been linked to adverse birth outcomes; however, critical windows for such exposure during fetal growth remain unknown. We aimed to assess trimester-specific associations of vanadium exposure with ultrasound measures of fetal growth and birth size in a Chinese longitudinal cohort. Methods: The present study was embedded in our ongoing prospective prenatal cohort study at the Wuhan Women and Children Medical Care Center (Wuhan, Hubei, China). Pregnant women were eligible for inclusion if they provided signed informed consent and were less than 16 weeks pregnant with a single gestation, and agreed to take in-person interviews, undergo ultrasound examinations, and provide blood and urine samples. We collected urine samples and measured urinary vanadium concentrations using inductively coupled plasma mass spectrometry. We calculated SD scores for ultrasound-measured biparietal diameter, head circumference, occipitofrontal diameter, abdominal circumference, femur length, and estimated fetal weight at 16, 24, and 31 weeks of gestation. We applied linear regressions with generalised estimating equations to estimate associations of urinary vanadium concentrations in each trimester with ultrasound-measured fetal growth parameters or neonatal size at birth. Findings: As of Oct 12, 2016, we recruited 3075 women who were non-smokers and non-drinkers during pregnancy, provided up to three urine samples during the first, second, and third trimesters, and gave birth to live singletons without birth defects. We excluded women who did not provide information on ultrasound measurements (n=20) or who only had one ultrasound measurement of fetal crown–rump length at the first trimester (n=14). We excluded another 16 women because they had missing values for confounding variables, leaving 3025 women retained in the study. Every doubling of urinary vanadium concentration in the first trimester was associated with a significant increase in femur length (adjusted percentage change 6·4%, 95% CI 0·7 to 12·1) at 16 weeks of gestation and reductions in biparietal diameter (−4·2%, −8·2 to −0·1), head circumference (−6·0%, −10·1 to −1·9), occipitofrontal diameter (−5·7%, −9·9 to −1·5), and abdominal circumference (−5·3%, −9·4 to −1·2) at 31 weeks of gestation. Every doubling of urinary vanadium concentration in the second trimester was significantly associated with reductions in SD scores for head circumference (−7·2%, −14·1 to −0·3) and abdominal circumference (−6·9%, −13·8 to −0·1) at 31 weeks of gestation. The highest quartile of urinary vanadium concentration (>1·18 μg/L) in the first trimester, when compared with the lowest quartile (≤0·60 μg/L), was associated with a mean decrease in birthweight of 12·6 g (95% CI 2·5–22·8; ptrend=0·0055) and a mean decrease in ponderal index of 0·07 kg/m3 (0·01–0·12; ptrend=0·0053). Moreover, newborns with restricted birth size had higher vanadium exposure in the first and third trimesters. Interpretation: Vanadium might be toxic to humans and impair fetal growth. The first, early second, and late third trimesters could be critical windows for heightened vulnerability to vanadium for fetal growth. Our findings require further investigation in other populations. Funding: National Key R&D Plan of China, National Natural Science Foundation of China, and Fundamental Research Funds for the Central Universities, Huazhong University of Science and Technology.

As a sudden public health event, the COVID-19 epidemic has brought a tremendous impact on the economic and social development of China. Its biggest and most direct impact is in the tertiary industry, especially the cultural tourism industry, which has a more far-reaching impact. This paper takes Guangxi as an example to study the current situation, problems, and future development direction of the cultural tourism industry in the post-epidemic era. The study found that the response to the epidemic in ethnic minority areas represented by Guangxi was timely and rapid, but due to their industrial resilience and the impact of the epidemic, the revitalization of the culture and tourism industry is still facing severe challenges. Therefore, this article put forward the key countermeasure to promote the cultural tourism industry revitalization of ethnic minority areas from list management, elements of development management, project construction, industry integration, and international cooperation, to provide policy recommendations and theoretical basis for the revitalization of the cultural tourism industry in ethnic minority areas.

For systems with spatial and nonspatial symmetries, the topological classification depends not only on these symmetries but also on the commutation/anticommutation relations between spatial and nonspatial symmetries. The coexistence of spatial and nonspatial symmetries together with appropriate commutation/anticommutation relations between them can give rise to crystalline and higher-order topological phases, which host gapless boundary modes. Alternatively, space-time symmetries in a Floquet system can take the role of spatial symmetries in deciding the topological classification. Promoting a spatial symmetry to a space-time symmetry can alter the commutation relations, which in turn can modify the topological properties of the system. We show how a coherently excited phonon mode can be used to promote a spatial symmetry with which the static system is always trivial to a space-time symmetry which supports a nontrivial Floquet topological phase. We demonstrate this effect by considering two systems: The first is a second-order topological superconductor, and the second is a first-order crystalline topological insulator. In both these cases, a coherently excited phonon mode is responsible for promoting the reflection symmetry to a time-glide symmetry. This newly introduced symmetry allows the previously trivial system to host gapless modes. In the first case, these are protected corner modes, while in the second case, these are gapless edge modes.

We aim to investigate the correlations between hemodynamic parameters, penile rigidity grading, and the therapeutic effects of phosphodiesterase type 5 inhibitors using color Doppler flow imaging after intracavernosal injection in patients with erectile dysfunction. This study involved 164 patients. After intracavernosal injection with a mixture of papaverine (60 mg), prostaglandin E 1 (10 mg), and lidocaine (2%, 0.5-1 ml), the penile vessels were assessed using color Doppler flow imaging. Penile rigidity was classified based on the Erection Hardness Score system as Grades 4, 3, 2 or 1 (corresponding to Schramek Grades V to II). Then, the patients were given oral sildenafil (50-100 mg) and scored according to the International Index of Erectile Function (IIEF-5) questionnaire. The number of patients with penile rigidities of Schramek Grades II to V was 14, 18, 21, and 111, respectively. The IIEF-5 score was positively correlated with the refilling index of the penile cavernosal artery (r = 0.79, P< 0.05), the peak systolic velocity (r = 0.45, P< 0.05), and penile rigidity (r = 0.75, P< 0.05), and was negatively correlated with the end diastolic velocity (r = −0.74, P< 0.05). For patients with erectile dysfunction, both the IIEF-5 score after sildenafil administration, which is correlated with penile rigidity, and the hemodynamic parameters detected using color Doppler flow imaging may predict the effects of phosphodiesterase type 5 inhibitor treatment and could provide a reasonable model for the targeted-treatment of erectile dysfunction.

Root hair elongation relies on polarized cell expansion at the growing tip. As a major osmotically active ion, potassium is expected to be continuously assimilated to maintain cell turgor during hair tip growth. However, due to the lack of practicable detection methods, the dynamics and physiological role of K+ in hair growth are still unclear. In this report, we apply the small-molecule fluorescent K+ sensor NK3 in Arabidopsis root hairs for the first time. By employing NK3, oscillating cytoplasmic K+ dynamics can be resolved at the tip of growing root hairs, similar to the growth oscillation pattern. Cross-correlation analysis indicates that K+ oscillation leads the growth oscillations by approximately 1.5 s. Artificially increasing cytoplasmic K+ level showed no significant influence on hair growth rate, but led to the formation of swelling structures at the tip, an increase of cytosolic Ca2+ level and microfilament depolymerization, implying the involvement of antagonistic regulatory factors (e.g., Ca2+ signaling) in the causality between cytoplasmic K+ and hair growth. These results suggest that, in each round of oscillating root hair elongation, the oscillatory cell expansion accelerates on the heels of cytosolic K+ increment, and decelerates with the activation of antagonistic regulators, thus forming a negative feedback loop which ensures the normal growth of root hairs.

In this study, preparation of Al–Mg–Sc master alloy tests were carried out by Al–Mg thermoreduction method. Stirring by blowing argon and pressing with molten salt jar were adopted to reduce scandium segregation and upgrading scandium recovery of scandium-bearing master alloy. The results show that the Al–Mg–Sc master alloy ingot contained 2.90% Sc, 5.73% Mg, 0.0058% Cu, 0.29%, 0.029% Ti, 0.13% Fe, 0.075% Zn, 0.025% Na, and 96.72% recovered scandium obtained under the comprehensive conditions used: m(Al): m(Mg): m(ScCl3) = 10:1:1.5, stirring speed of eight rpm, reduction temperature of 1223 K, reduction time of 40 min. The experimental results are in agreement with the thermodynamic predictions, and Al–Mg–Sc master alloy indicator was ideal.

In this study, a one-step rapid heating novel process was used to prepare high-purity anhydrous scandium chloride molten salt with low-purity scandium oxide. High-purity anhydrous ScCl3 molten salt was used as the Sc-bearing raw material for preparing the Sc-bearing master alloy. Inert gas was used to enhance the purity of anhydrous scandium chloride and reduce the hydrolysis rate of scandium. The results show that high-purity scandium chloride (purity, 99.69%) with the scandium content of 29.61%, was obtained, and the hydrolysis rate of scandium was 1.19% under the conditions used: removing ammonium chloride; residual crystal water temperature of 400 °C; m(Sc2O3):m(NH4Cl) = 1:2.5; holding-time of 90 min; heating-rate of 12 °C/min; and argon flow of 7.5 L/min. XRD, SEM, and EPMA analyses further verified that anhydrous scandium chloride crystallization condition was relatively good and the purity of high-purity anhydrous scandium chloride approached the theory purity of anhydrous scandium chloride.

Composite structures have become increasingly popular in civil engineering due to many advantages, such as light weight, excellent corrosion resistance and high productivity. However, they still lack the strength, stiffness, and convenience of constructions of fastener connections in steel structures. The most popular fastener connections in steel structures are slip-critical connections, and the major factors that influence their strength are the slip factors between faying surfaces and the clamping force due to the prevailing torque. This paper therefore examined the effect that changing the following parameters had on the slip factor: (1) replacing glass fiber reinforced plastic (GFRP) cover plates with stainless-steel cover plates; (2) adopting different surface treatments for GFRP-connecting plates and stainless-steel cover plates, respectively; and (3) applying different prevailing torques to the high-strength bolts. The impact on the long-term effects of the creep property in composite elements under the pressure of high-strength bolts was also studied with pre-tension force relaxation tests. It is shown that a high-efficiency fastener connection can be obtained by using stainless-steel cover plates with a grit-blasting surface treatment, with the maximum slip factor reaching 0.45, while the effects of the creep property are negligible.