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Harvesting the omnipresent mechanical energy emerges as an essential solution in combating environmental pollution and alleviating energy deficits. However, the ultra‐low frequencies and variable amplitudes of most ambient mechanical energy pose significant challenges to effective energy harvesting. To address this issue, this paper reports an innovative triboelectric nanogenerator based on pendulum‐rotation transmission mechanism (PR‐TENG) designed for efficacious harvesting of continuous low‐frequency mechanical energy. It comprises two synergistic units: a transmission unit and a power‐generating unit. The transmission unit is capable of converting external low‐frequency mechanical excitations into unidirectional rotation. Through an internal speed‐increasing mechanism, the rotational speed of the rotor can be further elevated, thereby enabling the power‐generating unit to produce a frequency‐multiplied output and markedly improving the energy transduction efficiency. The mechanism of triboelectrification employed by the power‐generating unit further reduces the total weight of the device, thus advancing its portability. In addition, the coherent coaxial configuration of the device's components significantly enhances compactness and optimizes spatial efficiency. As a practical power source, the PR‐TENG is shown to be capable of directly powering LEDs. Owing to its distinctive operational mechanism and structural innovation, the PR‐TENG is a promising method to efficiently harvest low‐frequency mechanical energy from the ambient environment. [ABSTRACT FROM AUTHOR]

Ocean wave energy is a promising green energy source, but it is difficult to exploit on a large scale due to its low frequency and the random uncertainty of its direction. In this study, a spherical eccentric structured triboelectric nanogenerator (Se‐TENG) is designed to harvest omnidirectional low‐frequency water wave energy. Power management circuits (PMM) are designed to optimize the utilization of water wave energy at low frequencies for large‐scale conversion and storage. It is found that the output performance of the Se‐TENG device is influenced by the frequency of the water waves, with the best output performance at a water wave frequency of 2.0 Hz, given that the wave amplitude is 9 cm. It is verified that within the Se‐TENG, the parallel connections of eccentric structured triboelectric nanogenerators (E‐TENGs) are more conducive to energy storage and conversion. In addition, the Se‐TENG used in conjunction with an energy storage device is able to successfully power light‐emitting diodes (LEDs) and digital thermometers, demonstrating its ability to harvest low‐frequency water wave energy in random directions. The unique structure of the Se‐TENG offers an innovative and effective way of gathering blue energy on a large scale. [ABSTRACT FROM AUTHOR]

Crystal scaling in gas-liquid two phase flow pipes is a common issue in many fields, such as chemical engineering, water industries, and energy industries, posing a great threat to the production process and the environment. The characters of air bubbles in the bubble flow have a serious impact on the ultrasonic guided wave descaling inside a pipe. The interaction mechanism between the air bubbles with various sizes and the cavitation bubbles are studied in this paper by combined the finite element method and the bubble dynamics equation, qualitatively analyzing the impact of the air bubble size and the acoustic pressure in the fluid field on the leaky ultrasonic guided waves descaling. The numerical and experiment results show that the maximum expansion radius ratio of cavitation bubble is suppressed from 2.4 to 1.3 when the radius of air bubble grows from 0.5 mm to 4.5 mm. The Ca content removal ratio at 35.5 cm was 81 %, 66 % and 28 %, while the Ca content removal ratio at 60 cm was 76 %, 56 % and 16 % when the gas outlet orifice is 100 μm, 200 μm and 300 μm respectively in the experiment. The results indicate that large bubbles in two phase flow inhibit the cavitation effect of cavitation bubbles and reduce the effectiveness of descaling. • Effect of bubble size on two phase flow pipe fouling removal based on leaky ultrasonic guided waves. • A theoretical guidance for the removal of fouling online in bubble flow pipes. • Bubble motion characteristics were investigated by coupling FEA and Keller-Miksis equation. [ABSTRACT FROM AUTHOR]

• Proposed a new descaling approach for fluid-conveying pipes in water industries. • Built a finite element model for the leaky guided ultrasonic waves cavitation. • Proposed a frequency selecting principle for non-destruction and uniformity. Fouling is inevitable in fluid-conveying pipes which can decrease flow rate, reduce thermal conductivity and increase energy consumption significantly, even cause industrial accidents. As there are some drawbacks in existing descaling methods, a new approach based on leaky guided ultrasonic waves cavitation is proposed in this paper, which is non-destructive and able to cut down downtime costs compared to the existing methods. This paper includes theoretical studies, finite element modeling work and a series of experiments. A frequency selection principle has been proposed to assure that the descaling process is non-destructive and uniform. The results show that this new approach is of high efficiency in descaling a water-filled pipe. [ABSTRACT FROM AUTHOR]

The present study aimed to identify novel intervertebral disc degeneration (IDD)‑associated long noncoding (lnc)RNAs and genes. The lncRNA and mRNA microarray dataset GSE56081 was downloaded from the Gene Expression Omnibus database and included 5 samples from patients with degenerative lumbar nucleus pulposus and 5 normal controls. Differentially expressed lncRNAs or differentially expressed genes (DEGs) were identified and co‑expression network analysis was performed followed by functional analysis for genes in the network. Additionally, a microRNA (miRNA)‑lncRNA‑mRNA competing endogenous RNA (ceRNA) regulatory network was constructed based on DEGs and lncRNAs in the co‑expression network. Furthermore, a literature search was performed to identify specific miRNAs that had been previously associated with IDD and a specific miRNA‑associated ceRNA network was extracted from the co‑expression network. A total of 967 genes and 137 lncRNAs were differentially expressed between IDD samples and controls. A co‑expression network was constructed and contained 39 differentially expressed lncRNAs and 209 DEGs, which were primarily involved in ʻskeletal system developmentʼ, ʻresponse to mechanical stimulusʼ and ʻbone developmentʼ. Furthermore, a ceRNA network was established, including 79 miRNAs, 9 downregulated lncRNAs and 148 DEGs. The identified miRNAs included a previously reported disease‑associated miRNA, hsa‑miR‑140. The present study demonstrated that hsa‑miR‑140 was regulated by three lncRNAs in the hsa‑miR‑140‑associated ceRNA network, including KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1), OIP5 antisense RNA 1 (OIP5‑AS1) and UGDH antisense RNA 1 (UGDH‑AS1). KCNQ1OT1 was co‑expressed with neurochondrin (NCDN) and lon peptidase 2, peroxisomal. In addition, the lncRNAs OIP5‑AS1 and UGDH‑AS1 targeted several overlapping co‑expressed genes, including forkhead box F1 (FOXF1) and polycystin 1, transient receptor potential channel interacting (PKD1). Therefore, KCNQ1OT1 may regulate the expression of NCDN, and OIP5‑AS1 and UGDH‑AS1 may affect the expression of FOXF1 and PKD1 in IDD. Further experiments are required to validate the results of the present study, which may provide valuable insights into the identification of novel biomarkers associated with IDD. [ABSTRACT FROM AUTHOR]

Natural gas hydrate, which forms and agglomerates under the condition of low temperature and high pressure, can easily affect production or even lead to serious accidents. In order to prevent hydrate agglomeration in a pipeline, the industries generally add seriously excess inhibitor with experience, which causes serious environmental pollution and huge costs. However, due to the uncontrollable production and environmental conditions, hydrate plugging in a pipeline still occurs. According to the issues above, the method, for hydrate agglomeration online monitoring in a natural gas pipeline based on acoustic active excitation, has been presented in this paper. The method is to monitor and locate the hydrate agglomeration in a pipeline in order to take measures in time. Both the modeling and the experimental results show that the method can monitor and locate the hydrate agglomeration online at different locations with good accuracy. [ABSTRACT FROM AUTHOR]

• Online defect detection technology for multi-strand aircraft wire insulation layer. • Offering early warning before aircraft wire failure. • The method proposed in this paper is of high defect localization accuracy. Aircraft wire insulation layer with defects can cause serious accidents that threaten the life of the people on board. Compared with the traditional aircraft wire detection methods, an on-line detection for multi-strand aircraft wire (MSAW) based on ultrasonic guided waves (UGWs) is proposed. In this paper, the propagation characteristics of UGWs in MSAW are investigated by numerical simulations and experiments. In the experiment, a 5 cycles Hanning window modulated sinusoidal waves with a center frequency of 20 KHz is employed as excitation signal. The experimental results show that this method effectively detect 4 different types of defects in a 3-strand aircraft wire and the maximum defect location relative error is 1.6 %. The amplitude of defect reflected echoes decrease as the axial length and circumferential ratio of these defects increased from 2 mm to 10 mm and 12.5 % to 100 %, respectively. An interesting phenomenon is found that the defects reflection energy in a wire can be acquired in other wires which shows that UGWs energy disperse among wires. The experiment successfully detected each defect in the MSAW, proving the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Objective: We performed a meta-analysis to assess association between interleukin 1 (IL-1) polymorphisms and the risk of Intervertebral Disc Degeneration (IDD). Background: A series of studies have investigated the association between common single nucleotide polymorphisms in IL-1 and IDD risk; however, the overall results are inconclusive. Methods: Two independent investigators conducted a systematic search for relevant available studies. Allele frequencies were extracted from each study. The association between the IL-1α (+889C/T) or IL-1β (+3954C/T) polymorphism and IDD risk was measured by odds ratios (OR) with 95% confidence intervals (95% CI). Results: Five and six studies, respectively, were ultimately included in the meta-analysis for the IL-1α (+889C/T) and IL-1β (+3954C/T) polymorphism. The combined results showed that the IL-1α (+889C/T) polymorphism was significantly associated with increased susceptibility to IDD, particularly in Caucasians (TT versus CC: OR = 2.95, 95% CI: 1.45, 6.04; Pheterogeneity = 0.82; TT versus CC/CT: OR = 2.29, 95% CI: 1.18, 4.47; Pheterogeneity = 0.20). In contrast, the IL-1β (+3954C/T) polymorphism showed a trend towards increased risk in Caucasians but no association in Asians. Conclusion: This meta-analysis suggested that the IL-1α (+889C/T) polymorphism is significantly associated with risk of IDD, especially in Caucasian populations. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the clinical efficacy of the treatment of scoliosis with a pedicle screw system through paraspinal intermuscular approach (PIA). Methods: This is a retrospective case series study. A total of 10 patients diagnosed with scoliosis had surgical indications and treated with a pedicle screw system in one‐stage posterior surgery by PIA from March 2013 to April 2015 at the First Hospital of Jilin University were enrolled in this study. The average age of the patients was 14.9 years, including one male and nine females. The operative information and surgical results, including Cobb angle correction, correction loss, global balance (including Frontal Plane Balance [FPB] and Sagittal Plane Balance [SPB]), and fusion rate were reviewed. Functional outcomes including visual analog scale (VAS) back pain score, leg pain score, and Scoliosis Research Society‐22 questionnaire (SRS‐22) were used to evaluate the quality of life of patients preoperatively and at last follow‐up. Results: Each patient was followed up at least six times. The average follow‐up time was 43.2 months. Mean scoliosis and kyphosis improved from 68.5° ± 18.1°to 18.7° ± 11.8° and from 34.4° ± 17.9°to 24.0° ± 6.7°, respectively (p < 0.05); at last follow‐up, it was 20.1° and 24.7°, respectively (p > 0.05). During the follow‐up, mean coronal and sagittal correction loss was 1.4° ± 1.2°and 0.7° ± 0.8°, respectively (p > 0.05). Mean FPB improved from 32.7 to 11.7 mm (p < 0.05); Mean SPB changed from 0.3 to −0.7 mm (p > 0.05). No dural tears were observed during the corrective surgery or wound infection or implant‐related complications. No pseudoarthrosis was identified according to the last follow‐up three‐dimensional (3D) CT scan. All the domains in SRS‐22 questionnaire show statistically significant improvement at the last follow‐up (p < 0.05). The VAS back pain scores improved from a mean preoperative score of 1.7 to a mean postoperative score of 0.2 (p < 0.05). Conclusion: This original one‐stage posterior PIA is safe and effective in the treatment of scoliosis, which is characterized with less blood loss, shorter operation time, and satisfactory bony fusion. [ABSTRACT FROM AUTHOR]

Abstract: A SVM-based pipeline leakage detection and pre-warning system is presented in this paper. In the system an optical cable is laid in parallel with a pipeline in the same ditch and three single mode optical fibers inside constitute the distributed vibration sensor. The sensor is based on Mach–Zehnder optical fiber interferometer and can detect the vibration signals along a pipeline in real time. Then the eigenvectors of vibration signals are extracted by “energy-pattern” method based on wavelet packet decomposition. Subsequently the vibration signals are recognized by support vector machine (SVM) through the features so that it can judge whether any abnormal event is taking place. If any abnormal event is found along a pipeline, the location is thus calculated. A series of trials in situ have been done, showing that the system is of good accuracy and real time performance both in recognition and locating. [Copyright &y& Elsevier]

In this paper, pipeline abnormal events (hydrate blockage and pipeline leakage) were detected by an active acoustic excitation method based on pulse compression. The positions of pipeline abnormal events were determined by time delay between emitted and reflected signals. Besides, in order to effectively distinguish the two detection signals, the empirical mode decomposition (EMD) method was used to obtain the intrinsic mode function (IMF) of the detection signal, and the normalized energy of all IMF components was used as eigenvector to input to the support vector machine (SVM) classifier for classification. The experiment results demonstrated that the trained models could accurately classify hydrate blockage and pipeline leakage after adjusting the classification threshold by the Youden index. The evaluation indicators including accuracy, precision, recall, specificity, and F1-score were 100% and area under curve (AUC) was 1 in testing set. [ABSTRACT FROM AUTHOR]

As one of the most aggressive malignancies, osteosarcoma has high risks of death. Although long noncoding RNAs (lncRNAs) may promote the osteosarcoma progression as verified, the potential molecular mechanism of lncRNAs in osteosarcoma remains unknown. Herein, we analyzed lncRNA microarray of osteosarcoma and selected LINC01278 as the study object. Then, we found that the expression of LINC01278 tested by quantitative reverse‐transcription polymerase chain reaction was enhanced in tumor tissues compared with the para‐carcinoma tissues and related to clinical stage, distant metastasis in osteosarcoma. In addition, the clinical outcomes were poor in osteosarcoma patients with high LINC01278 level. Moreover, LINC01278 promoted proliferation and restrained apoptosis in osteosarcoma cells. Afterward, mechanistic studies turned out that LINC01278 was a competing endogenous RNA of parathyroid hormone type 1 receptor (PTHR1) in osteosarcoma by sponging miR‐133a‐3p, which was considered as a tumor inhibitor in osteosarcoma. Furthermore, PTHR1 downregulation restored the impacts of inhibited miR‐133a‐3p on the processes in osteosarcoma cells. Our findings clarified that the carcinogenic effect of LINC01278 in osteosarcoma was mediated through miR‐133a‐3p/PTHR1 signaling, creating a novel insight into good targets for the therapy and prognosis of osteosarcoma. [ABSTRACT FROM AUTHOR]

Pipelines have advantages in fluid transportation, which play an important role in the rise of economy and social development. However, fouling in pipelines is an important issue that must be paid attention to by oil, gas, food and many other industries. These related industries need to remove fouling and even replace pipes regularly due to the generation of fouling. If the descaling operation is not timely or improper, it will lead to pipeline deformation, leakage or even burst. Thus, an environmentally friendly descaling methodology is proposed in this paper, which is based on ultrasonic guided waves cavitation effect. Two descaling scenarios, single transducer case and the transducer array one, are studied through the modeling work and compared in the experiments, which show that the ultrasonic guided waves excited by the piezoelectric transducers can remove fouling effectively and descaling effect of the latter case is cleaner than the former one. The average descaling rates of two descaling system are up to 82.49% and 94.61% respectively. [ABSTRACT FROM AUTHOR]

Fouling inside pipeline, especially crystal fouling, is a common issue in the chemical industry, which poses great threat on process of cleaner production and environment. The influence of water flow velocity on the calcium carbonate crystal fouling removal in pipeline using eco-friendly ultrasonic guided wave technology has been studied in this paper, in order to apply this technique better in the real-world scenarios. The finite element simulation model of guided waves propagating in pipeline containing flowing water is established, in which the acoustic pressure distribution along the pipe has been obtained, showing that the guided waves attenuate under the flowing water inside pipelines. Then an experiment system of fouling removal in pipe with flowing liquid is set up. According to the descaling experimental results, it has been demonstrated that there is a better descaling performance with water velocity of 0 m/s in pipe, and in the other way the performance is weakened with flowing water. The above conclusions can be useful for online descaling process in chemical industries. • UGW technology is proposed to remove fouling in pipeline contained flowing water. • FE model is established to study influence of flow velocity on UGW propagation. • Experimental results show that water flow velocity weaken UGW descaling result. • The study provides a guidance for UGW online cleaning technology. [ABSTRACT FROM AUTHOR]

Fouling is inevitable on the surfaces of industrial equipment, especially on heat-exchanging surfaces in contact with fluids, which causes water pollution and destroys the ecological environment. In this paper, a novel fouling-removal methodology for plate structure based on cavitation by multi-frequency ultrasonic guided waves is proposed, which can remove fouling on stainless steel plates. A numerical simulation method has been developed to study the acoustic pressure distribution on a steel plate. According to the simulation results, the distribution of sound pressure on the plate under triple-frequency excitation is denser and more prone to cavitation than in single-frequency cases and dual-frequency cases, which improves fouling removal rate. The stainless steel plate is immersed in water for the descaling experiment, and the results show that the fouling removal rates of three water-loaded stainless steel plates under different single-frequency excitation seem unsatisfactory. However, the multi-frequency excitation improves the descaling performance and the removal rate of fouling reaches 80%. This new method can be applied to the surface descaling of large equipment plates, which is of great significance for purifying water quality and protecting the ecological environment. [ABSTRACT FROM AUTHOR]

A novel method which applies BP neural network (BPNN) to temperature calibration of fiber Bragg grating (FBG) sensors is proposed and discussed. Processing and analysis of experimental data showed that this method fitted very well the complex relationship between the center wavelength of FBG and temperature which is approximately linear in room temperature whereas nonlinear in low temperature. The maximum absolute error and root mean squared error were respectively 0.9434 °C, 0.2102 °C in fitting and 0.8943 °C, 0.2081 °C in testing which verified the advantage of BPNN fitting compared with the previous polynomial fitting. The forecasting performance of BPNN was also satisfactory. The novel FBG temperature calibration method based on BPNN has considerable application prospect in FBG temperature measurement. [ABSTRACT FROM AUTHOR]

Hydrate blockage and pipeline leakage are two common factors that threaten the safety of natural gas pipelines. However, most of the current research focuses on nonintrusive, passive-like techniques that can only detect one of these abnormal events, with occasional attention to identification technique. This paper introduces an active method to simultaneously detect hydrate blockage and pipeline leakage using intrusive sensors, and further presents a deep forest-based classification method for two types of abnormal events, which aims to avoid the problem that the classification of traditional deep learning depends on huge number of hard-to-acquire samples. Besides, network structure and parameters in deep learning affect the classification performance, and deep forest is just a better solution to this problem. The parameter tuning experiments results of deep forest show that the classification accuracies are mostly 100% whatever in training and testing, proving that different parameter settings have little effect on the classification accuracy. The stability and portability of the classification method are tested, and it is verified that this classification method is easy to implement and has strong universality, which is expected to be applied to other types of natural gas pipeline event classification. [ABSTRACT FROM AUTHOR]

The female Bombyx mori accumulates a large amount of egg proteins, mainly Vg and 30K, during egg formation to provide nutrition for embryo development. The synthesis and transport of Vg have been extensively studied, particularly the regulation of Vg transcription induced by 20E; however, the mechanism of 30K protein synthesis is poorly studied. As a model organism of the order Lepidoptera, B. mori has high reproduction potential. In the present study, we found that the FHL2 homologous gene (BmFhl2) in B. mori is involved in inhibiting female egg formation by influencing the synthesis of 30K protein. Interference of BmFhl2 expression in silkworm females increased 30K protein synthesis, accelerated ovarian development, and significantly increased the number of eggs produced and laid; however, the 20E pathway was inhibited. The transcription levels of Vg and 30Kc19 were significantly downregulated following BmFhl2 overexpression in the silkworm ovarian cell line BmN. The Co-IP assay showed that the potential binding protein of BmFHL2 included three types of 30K proteins (30Kc12, 30Kc19, and 30Kc21). These results indicate that BmFHL2 participates in egg formation by affecting 30K protein in female B. mori. [ABSTRACT FROM AUTHOR]

Background: Spinal cord injury (SCI) is a central nervous system (CNS) trauma involving inflammation and oxidative stress, which play important roles in this trauma's pathogenesis. Therefore, controlling inflammation is an effective strategy for SCI treatment. As a hormone, melatonin is capable of producing antioxidation and anti-inflammation effects. In the meantime, it also causes a neuroprotective effect in various neurological diseases. Nrf2/ARE/NLRP3 is a well-known pathway in anti-inflammation and antioxidation, and Nrf2 can be positively regulated by melatonin. However, how melatonin regulates inflammation during SCI is poorly explored. Therefore, it was investigated in this study whether melatonin can inhibit the NLRP3 inflammasome through the Nrf2/ARE signaling pathway in a mouse SCI model. Methods: A model of SCI was established in C57BL/6 mice and PC12 cells. The motor function of mice was detected by performing an open field test, and Nissl staining and terminal deoxynucleotidyl transferase dUTP nick end labeling were carried out to evaluate the survival of neurons. Mitochondrial dysfunction was detected by transmission electron microscopy (TEM) and by assessing the mitochondrial membrane potential. In addition, the expression of NLRP3 inflammasome and oxidative-stress-related proteins were detected through Western blot and immunofluorescence double staining. Results: By inhibiting neuroinflammation and reducing neuronal death, melatonin promotes the recovery of neuromotor function. Besides this, melatonin is able to reduce the damage that causes neuronal mitochondrial dysfunction, reduce the level of reactive oxygen species (ROS) and malondialdehyde, and enhance the activity of superoxide dismutase and the production of glutathione peroxidase. Mechanically, melatonin inhibits the activation of NLRP3 inflammasomes and reduces the secretion of pro-inflammatory factors through the Nrf2/ARE signaling. Conclusions: In conclusion, melatonin inhibits the NLRP3 inflammasome through stimulation of the Nrf2/ARE pathway, thereby suppressing neuroinflammation, reducing mitochondrial dysfunction, and improving the recovery of nerve function after SCI. [ABSTRACT FROM AUTHOR]

The lack of operation and maintenance data brings difficulties to traditional risk assessment based on probability methods. Therefore, experts are invited to evaluate the key performance indicators related to system risk. These evaluation results are usually described by ambiguous language, so they have epistemic uncertainty. Uncertainty theory is a branch of mathematics used to model experts' degrees of belief. The uncertain measure has duality, that is, some symmetry, which means that the sum of the uncertain measure of an event and the uncertain measure of its complementary set is equal to 1. Therefore, the risk occurrence time of each basic event evaluated by experts is modeled by the uncertain variable in this article. Then, the risk assessment method of systems with epistemic uncertainty is proposed based on an uncertain fault tree analysis. Furthermore, two risk-based maintenance optimization models for systems with epistemic uncertainty are established. In particular, the leakage risk assessment method and the two risk-based maintenance optimization models for a subsea production system are considered, and the optimization results are given. The optimization results can help practitioners to warn of the leakage risk and make scientific maintenance decisions based on expert knowledge, so as to extend the service life of subsea production systems. [ABSTRACT FROM AUTHOR]

Rearing silkworms (Bombyx mori) using formula feed has revolutionized traditional mulberry feed strategies. However, low silk production efficiencies persist and have caused bottlenecks, hindering the industrial application of formula feed sericulture. Here, we investigated the effects of formula feed amino acid composition on silk yields. We showed that imbalanced amino acids reduced DNA proliferation, decreased Fib-H , Fib-L , and P25 gene expression, and caused mild autophagy in the posterior silk gland, reducing cocoon shell weight and ratio. When compared with mulberry leaves, Gly, Ala, Ser, and Tyr percentages of total amino acids in formula feed were decreased by 5.26%, while Glu and Arg percentages increased by 9.56%. These changes increased uric acid and several amino acids levels in the hemolymph of silkworms on formula feed. Further analyses showed that Gly and Thr (important synthetic Gly sources) increased silk yields, with Gly increasing amino acid conversion efficiencies to silk protein, and reducing urea levels in hemolymph. Also, Gly promoted endomitotic DNA synthesis in silk gland cells via phosphoinositide 3-kinase (PI3K)/Akt/target of rapamycin (TOR) signaling. In this study, we highlighted the important role of Gly in regulating silk yields in silkworms. • Amino acid imbalances are important factors causing silk yield reductions of silkworms reared on formula feed. • Addition of glycine and threonine to formula feed can increase cocoon shell weight and rate. • Glycine can promote endomitotic DNA synthesis in silk gland cells via PI3K/Akt/TOR signaling. [ABSTRACT FROM AUTHOR]

Peripheral nerve injuries represent one of the most common causes of permanent disabilities. Therapeutic electrical stimulation has been widely used in neural regeneration for decades. Combined with the implantation of a nerve cuff, several outcomes have proven effectiveness and feasibility in neuroprosthetic applications. However, the current electrical stimulation strategy fails to complete nerve repair. There is a lack of research on long‐term implantable nanogenerators in the neurostimulation scenario. Especially considering many disease models, those devices may not reach the in vitro simulative working setting. Thus, an implanted sciatic nerve stimulation system that spontaneously generates biphasic electric pulses in response to rats' movement is developed. The electric signals generated by this device could stimulate injured sciatic nerve by cuff electrode. This work introduces an implantable self‐regulated neural electrical stimulation system generated by a contact separation triboelectric nanogenerator with a nerve cuff electrode and compares it with chronic therapeutic electrical stimulation for sciatic nerve restoration effect. Neural function restoration is observed in gait and histological analysis. Moreover, the upregulation of growth associated protein 43 can be a protentional target. This could have potential clinical application in facilitating closed‐loop energy harvesting for long‐term electrical stimulation. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the effects of a shrinkage reducing agent (SRA) and Portland expanded cement (PEC) on the fluidity, mechanical properties, and shrinkage performance of ultrahigh-performance concrete (UHPC). The results indicated that the fluidity of the fresh UHPC mortar initially decreased and then increases along as a function of SRA dosage. When the dosage of SRA was 1%, the UHPC mortar fluidity was at its minimum. For dosages exceeding 1%, the additional water-binder ratio of the mortar increased, which in turn increased the UHPC fluidity. That is, the SRA delayed the cement hydration and increased the setting time, which is not conducive for early strength development of UHPC. As the SRA dosage was increased (i.e., 0%–2%), the autogenous shrinkage of UHPC decreased significantly such that even a small dosage of about 0.5% SRA was able to effectively reduce drying shrinkage. From the study results, it was also observed that PEC accelerated the loss of fluidity in the fresh UHPC and concurrently promoted the early strength development of UHPC. At 75% PEC content, the strength enhancement effects tended to be stable. This means that although the addition of PEC will potentially increase the autogenous shrinkage of UHPC, it has the positive effect of inhibiting drying shrinkage provided that the PEC dosage is controlled within the 25%–50% range. Furthermore, morphological analyses using a scanning electron microscope (SEM) indicated that an increase in the SRA dosage loosens the UHPC microstructure, with the formation of the hydration products remaining incomplete, thus ultimately causing the UHPC strength to decrease. Overall, the study findings indicated that 2% SRA and 25%–50% PEC can effectively reduce the shrinkage of UHPC and are, therefore, recommended as the optimum dosages. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to build a predictive model of lower lumbar instability. Methods: This retrospective study included 199 patients. Patients were divided into the lower lumbar instability group (LLIG) (n = 98) and lower lumbar stability group (LLSG) (n = 101). All participants of LLIG were recruited over a 2‐year period (2015–2017) from the patients who accept lumbar surgery at the First Hospital of Jilin University. The LLSG was selected from outpatients who had underwent lumbar spine computed tomography (CT) and Flexion and extension radiographs (FER) at the First Hospital of Jilin University from 2015 to 2017. Several lower lumbar parameters were measured, including Lordosis angle (LA), intervertebral height (IH), ratio of anterior height to posterior height (APR), angle between endplate and anterior edge of vertebral body (AEPVa), sagittal slip ratio (SSR), and angle between the upper endplate and z‐axis on sagittal plane (AUEZS). These parameters were keyed into the SPSS software to create a predictive model for classification. Sensitivity, specificity, predictive accuracy, and Kappa value were used to evaluate the predictive model. Results: Compared with LLSG, the LA of LLIG decreased by 3.49° (126.54° vs 130.3°). Similarly, the IH of LLIG decreased by 1.23°mm, 1.66°mm, and 0.71°mm at L3‐4, L4‐5, and L5‐S1. Compared with LLSG, the SSR of LLIG is higher at L3‐4, L4‐5, and L5‐S1 (0.54 vs 0.51, 0.57 vs 0.46, and 0.59 vs 0. 47). Moreover, the APR of LLIG is higher than those of LLSG at L3‐4, L4‐5, and L5‐S1 (1.97 vs 1.81, 2.40 vs 1.97, and 2.69 vs 2.26). The LLIG has bigger AEPVa than LLIG at L3‐4, L4‐5, and L5‐S1. Compared with LLSG, the AUEZS of LLIG is bigger at L3‐4 (91.75° vs 90.81°) and smaller at L4‐5 and L5‐S1(84.63° vs 85.85° and 73.27° vs 75.01°). The SSR (L4) show highest predictive accuracy (83%) when every parameter was fed to LDA classifier to generate a univariate model. All parameters represent a statistically significant difference (P < 0.05) between LLSG and LLIG. The model including LA, APR (L5‐S1), IH (L4‐5), SSR (L5), AUEZS (L5) has highest predictive accuracy of 88.2%. The sensitivity, specificity, and Kappa value are 88.7%, 93.1%, and 0.77. Conclusion: The predictive model has good classification performance and can be an auxiliary tool for clinicians to evaluate lumbar instability in preoperative patients with severe pain aggravated by lumbar movement. [ABSTRACT FROM AUTHOR]

• Building a defect detection system of aircraft cable insulation layer. • Using ultrasonic guided waves to detect multiple defects simultaneously. • Using deep forest method to identify defect categories. Due to the special internal environment of aircraft, cable damage is inevitable, which usually starts from insulation layer defects and may cause major economic losses, and even seriously threaten the life of people on board. According to the above issue, a defect detection system for aircraft cable insulation layer based on ultrasonic guided waves (UGWs) is built in this paper. In order to ensure the complete coupling between the sensor and the insulation layer of the aircraft cable, the macro fiber composite (MFC) flexible sensor is employed in the system. Both simulation and experimental results show that this method can simultaneously monitor four different types (abrasion, cut, semi-stripping and full-stripping) of cable insulation layer defects at different locations on the same cable. The reflection signals of different types of defects are extremely similar and difficult to distinguish directly. In this paper, a classification method for four types of defects based on the deep forest method is proposed. This method requires a small sample size, and the classification performance is not affected by network structure and parameters. The recognition accuracy can reach 100%, avoiding the problem of traditional deep learning classification relying on a large number of samples and requiring parameter adjustment. The proposed method in this paper is proven to be able to effectively carry out online monitoring and accurately classify defect types, which has guiding significance for aircraft maintenance personnel to take corresponding measures in time. [ABSTRACT FROM AUTHOR]

To investigate how a back propagation neural network based on genetic algorithm (GA-BPNN) optimizes the low-intensity pulsed ultrasound (LIPUS) stimulation parameters to improve the bone marrow mesenchymal stem cells (BMSCs) viability further. The LIPUS parameters were set at various frequencies (0.6, 0.8, 1.0, and 1.2 MHz), voltages (5, 6, 7, and 8 V), and stimulation durations (3, 6, and 9 minutes). As only some discrete points can be set up in the experiments, the optimal LIPUS stimulation parameter may not be in the value of these settings. The GA-BPNN algorithm is used to optimize parameters of LIPUS to increase the BMSCs viability further. The BMSCs viability of the LIPUS-treated group was improved up to 19.57% (P<0.01). With the optimization via the GA-BPNN algorithm, the viability of BMSCs was further improved by about 5.36% (P<0.01) under the optimized condition of 6.92 V, 1.02 MHz, and 7.3 min. LIPUS is able to improve the BMSCs viability, which can be improved further by LIPUS with parameter optimization via GA-BPNN algorithm. [ABSTRACT FROM AUTHOR]

• A gas pipeline safety monitoring method based on pulse-compression is proposed. • The location error of hydrate plugging and leak can reach 0.0011 m and 0.001 m. • The novel technique can monitor the hydrate formation process in real time. • The spatial resolution is improved to 0.32 m by pulse-compression. • The interference of noises is reduced significantly thanks to matched filtering. A novel method based on acoustic pulse-compression and envelope extraction is proposed and discussed to detect and locate hydrate blockage and leak in natural gas pipelines. Linear frequency modulation (LFM) signal rather than single frequency sinusoidal signal is emitted to inspect the pipeline. Reflected signal is firstly processed through a matched filter and then demodulated with Hilbert transform so that the envelope is obtained. By envelope subtraction, the detection and location of hydrate blockage and leak can be achieved. Based on the measurement and signal processing principle, a simulation model has been established with COMSOL which verifies the feasibility of the method. Experimental results demonstrate that the technique can not only locate hydrate blockage and pipeline leak precisely but also monitor the hydrate formation process in real time. Besides, the spatial resolution is improved and the interference of noises is reduced significantly thanks to matched filtering. The novel method has significantly enhanced the performance of existing system and has considerable application prospect in natural gas pipeline safety online monitoring. [ABSTRACT FROM AUTHOR]

• The technique can locate both hydrate plugging and leakage. • The accuracy of multiple positioning is good. • The size of hydrate plugging and leakage can be estimated. • Hydrate plugging and leakage can be distinguished using chaotic analysis method. Hydrate plugging and leakage are big issues in natural gas industry which can lead to huge economic costs, serious environmental destruction and life loss. In this paper, the acoustic reflection theories for leakage detection are studied and the chaotic characteristics of the detected signals are analyzed to distinguish hydrate plugging and leakage. A monitoring prototype system has been built for trials, in which incident acoustic waves are emitted into a pipeline by a transmitter and reflected waves caused by hydrate plugging or leakage are acquired by a receiver near the transmitter and amplified for further analysis. The experimental results demonstrate that the system can detect and locate both hydrate plugging and leakage at multiple positions online with good accuracy. Signal analysis results indicate that the difference in the chaotic characteristics of the detected signals for hydrate plugging and leakage could be used to distinguish the two types of abnormal events. [ABSTRACT FROM AUTHOR]

Lift-off variation causes errors in eddy current measurement of nonmagnetic plates as well as magnetic plates. For nonmagnetic plates, previous work has been carried out to address the issue. In this paper, we follow a similar strategy, but try to reduce the lift-off effect on another index—zero-crossing frequency for magnetic plates. This modified index, termed as the compensated zero-crossing frequency, can be obtained from the measured multifrequency inductance spectral data using the algorithm we developed in this paper. Since the zero-crossing frequency can be compensated, the permeability of magnetic plates can finally be predicted by deriving the relation between the permeability and zero-crossing frequency from Dodd and Deeds method. We have derived the method through mathematical manipulation and verified it by both simulation and experimental data. The permeability error caused by liftoff can be reduced within 7.5%. [ABSTRACT FROM PUBLISHER]

Background/Aims: Mechanical load can regulate disc nucleus pulposus (NP) biology in terms of cell viability, matrix homeostasis and cell phenotype. N-cadherin (N-CDH) is a molecular marker of NP cells. This study investigated the role of N-CDH in maintaining NP cell phenotype, NP matrix synthesis and NP cell viability under high-magnitude compression. Methods: Rat NP cells seeded on scaffolds were perfusion-cultured using a self-developed perfusion bioreactor for 5 days. NP cell biology in terms of cell apoptosis, matrix biosynthesis and cell phenotype was studied after the cells were subjected to different compressive magnitudes (low- and high-magnitudes: 2% and 20% compressive deformation, respectively). Non-loaded NP cells were used as controls. Lentivirus-mediated N-CDH overexpression was used to further investigate the role of N-CDH under high-magnitude compression. Results: The 20% deformation compression condition significantly decreased N-CDH expression compared with the 2% deformation compression and control conditions. Meanwhile, 20% deformation compression increased the number of apoptotic NP cells, up-regulated the expression of Bax and cleaved-caspase-3 and down-regulated the expression of Bcl-2, matrix macromolecules (aggrecan and collagen II) and NP cell markers (glypican-3, CAXII and keratin-19) compared with 2% deformation compression. Additionally, N-CDH overexpression attenuated the effects of 20% deformation compression on NP cell biology in relation to the designated parameters. Conclusion: N-CDH helps to restore the cell viability, matrix biosynthesis and cellular phenotype of NP cells under high-magnitude compression. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to evaluate the clinical efficacy of Aidi injection combined with CHOP chemotherapy regimen in the treatment of malignant lymphoma.Methods: We made an electronic search in the database of Wanfang, CNKI, and PubMed. All the clinical studies related to Aidi injection combined with CHOP chemotherapy regimen in the treatment of malignant lymphoma were screened and reviewed. The combined objective response rate (ORR), life quality improvement, and hematological toxicity were pooled by random- or fixed-effect model according to the heterogeneity across the included study. Moreover, the publication bias was evaluated by Begg's funnel plot and Egger's line regression test.Results: Eight prospective clinical trials with 513 subjects (273 in the Aidi injection plus CHOP group and 240 in the CHOP group) were included in this meta-analysis. The pooled results showed that Aidi injection combined with CHOP chemotherapy regimen can significantly improve the ORR (odds ratio [OR] =1.68, 95% confidence interval [CI]: 1.09-2.60, P < 0.05), improve the life quality (OR = 3.32, 95% CI: 1.97-5.58, P < 0.05), and decrease the risk of developing leukopenia (OR = 0.25, 95% CI: 0.17-0.39, P < 0.05) and thrombocytopenia (OR = 0.34, 95% CI: 0.22-0.53, P < 0.05).Conclusion: With the present evidence, Aidi injection combined with CHOP chemotherapy regimen can improve the treatment response and quality of life and decrease the risk of developing severe leukopenia or thrombocytopenia. [ABSTRACT FROM AUTHOR]

• The combinatorial optimization algorithm is applied to estimate the transformation matrix in hand eye calibration. • The influence of spherical mean square error and radius deviation on the calibration results is considered comprehensively. • It effectively reduces the random error, and has practical value for the hand eye calibration of industrial robots. In order to improve the measurement accuracy of laser profiler and industrial robot measurement system and reduce the influence of random error in calibration process, a hand eye calibration method based on combinatorial optimization is proposed. Firstly, the laser profiler is positioned by the robot to scan a standard sphere from different postures. Then, combinations from all the measurement data are selected to calculate several transformation matrices and the corresponding profile datasets in base coordinate system can be derived consequently. Since all the profile data come from the same stationary standard sphere, sphere fitting is applied to each dataset and the optimal hand eye transformation matrix can be derived which corresponds to the minimum fitting error. Experimental results show that the novel method can effectively improve the calibration accuracy and sphere loss which is weighted sum of sphere fitting error and radius error is reduced from 1.976 to 0.539 after combinatorial optimization. [ABSTRACT FROM AUTHOR]

Objective. Primary hepatic lymphoma is a rare disease. And the clinical manifestations of this disease are nonspecific. The objective of this paper is to improve clinicians’ understanding of this disease. Methods. We analyzed the clinical characteristics of a case of primary hepatic lymphoma in association with hepatitis B virus infection and reviewed the literature. Conclusion. The clinical manifestations of primary hepatic lymphoma are nonspecific. And it is easily misdiagnosed. Postoperative radiotherapy of patients with early stage was previously speculated to achieve favorable improvement. The application of targeted therapeutic drugs, chemotherapy, or combined local radiotherapy has become the first-line treatment strategy. [ABSTRACT FROM AUTHOR]

Bone-morphogenetic protein-7 (BMP-7) is a growth factor that plays a major role in mediating anabolism and anti-catabolism of the intervertebral disc matrix and cell homeostasis. In osteoblasts, Forkhead box protein C2 (FoxC2) is a downstream target of BMPs and promotes cell proliferation and differentiation. However, the role FoxC2 may play in degenerative human intervertebral disc tissue and the relationship between FoxC2 and BMP-7 in nucleus pulposus (NP) cells remain to be elucidated. This study aims to investigate the presence and signaling mechanisms of FoxC2 in degenerative human intervertebral disc tissue and NP cells. Western blot and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) analyses were used to measure FoxC2 expression in the NP tissue and cells. Transfections were carried out to measure the effect of FoxC2 on BMP-7-mediated extracellular matrix upregulation. Adenoviral knock-down of Smad1 was performed to investigate the mechanism of BMP-7-induced FoxC2 expression. In degenerative NP tissue, FoxC2 was markedly upregulated and positively correlated with increased disc degeneration. Induction of NP cell proliferation was confirmed by using cell counting kit-8 assay, immunocytochemistry and real-time qRT-PCR for Ki67. FoxC2 led to decreased noggin expression and increased Smad1/5/8 phosphorylation. During combined treatment with BMP-7, FoxC2 greatly potentiated anabolism through synergistic mechanisms on ECM formation. Combination therapy using BMP-7 and FoxC2 may be beneficial to the treatment of intervertebral disc degeneration. [ABSTRACT FROM AUTHOR]

Background context Corrective surgery for dystrophic scoliosis in neurofibromatosis Type 1 (NF-1) is challenging. There are various surgical methods, all with unsatisfactory outcomes. Purpose The purpose of the study was to evaluate the clinical outcomes of the treatment of dystrophic scoliosis in NF-1 with one-stage posterior pedicle screw approach. Study design This is a retrospective clinical study. Patient sample Sixteen patients with dystrophic scoliosis in NF-1 underwent one-stage posterior surgery with pedicle screw system. Outcome measurement We used preoperative and postoperative whole-spine radiographs to determine coronal and sagittal Cobb angles (curve correction); distance between apex vertebra and central sacral vertical line (DAC), pelvic obliquity, and shoulder tilt (coronal balance improvement); and sagittal vertical axis and pelvic tilt angle (sagittal balance improvement). We assessed the fusion rate using fusion segment computed tomography scan. Methods Patients underwent surgery with or without osteotomy according to spinal flexibility. Fusion segment selection method of fusion segments selection which mean fusing from one or two levels proximal to upper end vertebra to one or two levels distal to the lower end vertebra (EV+1 or 2) or stable vertebrae fusion. There were no study-specific conflict of interest–associated biases. Results The average follow-up time was 40.9 months. Mean scoliosis and kyphosis improved from 83.2° to 27.6° and 58.5° to 26.8°, respectively; at the last follow-up, it was 30.4° and 27.4°, respectively. Mean DAC, pelvic obliquity, and shoulder tilt improved from 53.0 to 23.9, 8.1 to 4.9, and 9.8 to 7.5 mm, respectively. Sagittal vertical axis and pelvic tilt angle improved from −5.8 to 1.6 mm and 17.9° to −5.8°, respectively. During follow-up, mean coronal and sagittal correction losses were 2.8° and 0.7°, respectively. Two EV+1 or 2 patients had decompensation. No pseudoarthrosis was identified. Conclusions The one-stage posterior pedicle screw approach is safe and effective in the treatment of dystrophic scoliosis in NF-1. Posterior vertebral column resection is recommended if flexibility is less than 35%. Stable vertebrae fusing is recommended. [ABSTRACT FROM AUTHOR]

Purpose: Femoral neck fracture is a frequent cause of hospitalization, and length of stay is an important marker of hospital cost and quality of care provided. As an extension of traditional statistical methods, machine learning provides the possibility of accurately predicting the length of hospital stay. The aim of this paper is to retrospectively identify predictive factors of the length of hospital stay (LOS) and predict the postoperative LOS by using machine learning algorithms.Method: Based on the admission and perioperative data of the patients, linear regression was used to analyze the predictive factors of the LOS. Multiple machine learning models were developed, and the performance of different models was compared.Result: Stepwise linear regression showed that preoperative calcium level (P = 0.017) and preoperative lymphocyte percentage (P = 0.007), in addition to intraoperative bleeding (p = 0.041), glucose and sodium chloride infusion after surgery (P = 0.019), Charlson Comorbidity Index (p = 0.007) and BMI (P = 0.031), were significant predictors of LOS. The best performing model was the principal component regression (PCR) with an optimal MAE (1.525) and a proportion of prediction error within 3 days of 90.91%.Conclusion: Excessive intravenous glucose and sodium chloride infusion after surgery, preoperative hypocalcemia, preoperative high percentages of lymphocytes, excessive intraoperative bleeding, lower BMI and higher CCI scores were related to prolonged LOS by using linear regression. Machine learning could accurately predict the postoperative LOS. This information allows hospital administrators to plan reasonable resource allocation to fulfill demand, leading to direct care quality improvement and more reasonable use of scarce resources. [ABSTRACT FROM AUTHOR]

Abstract: Phase distortion happens in the distributed optical fiber oil and gas pipeline leak detection and early warning system, which results in decreased sensitivity of the system and bigger location errors. This paper studies the birefringent characteristic of the optical fiber interferometer sensing arm, and the Jones matrix model of the optical polarization is established. On the basis of this model the optical path and location principle are improved by using two 3×3 couplers to acquire four light signals. Then, the demodulation method is adopted to get phase differences induced by perturbation of the two reverse optical paths, which are used subsequently in cross-correlation algorithm to achieve the time-delay estimation. Compared to the method of polarization control, this approach simplifies the system structure and reduces the cost. The trial results show that this method not only eliminates the effect of the phase distortion but also improves the system’s accuracy and locating stability. [Copyright &y& Elsevier]

Hereditary spherocytosis (HS) and Chronic myelocytic leukemia (CML) are both life threatening hemotologic diseases. They are rarely seen to occur simultaneously in one individual patient. Here we demonstrate a case of HS associated with CML in this study. The patient is a young female, diagnosed with HS in 2005, and was given partial embolization of the splenic artery. She got significant remission after the procedure. In 2008, she was found abnormal in blood routine test, after bone marrow routine, chromosome and fusion gene tests, she was diagnosed with CML (chronic phase). She did not receive regular treatment until 3 months prior, and is currently being treated with Dasatimib. She achieved hematological remission, but had no significant improvement in chromosome and fusion gene figures. Due to her severe condition of hemolysis, a splenectomy or an allogeneic hematopoietic stem cell transplantation is considered. [ABSTRACT FROM AUTHOR]

In many advanced industrial applications, the thickness is a critical index, especially for metallic coatings. However, the variance of lift-off spacing between sensors and test pieces affects the measured voltage or impedance, which leads to unreliable results from the sensor. Massive research works have been proposed to address the lift-off issue, but few of them applies to the thickness measurement of planar metallic films with finite-size circular (disk) geometry. Previously, a peak-frequency feature from the swept-frequency inductance was used to compensate the measurement error caused by lift-offs, which was based on the slow-changing rate of impedance phase term in the Dodd-Deeds formulas. However, the phase of measured impedance is nearly invariant merely on a limited range of sample thicknesses and working frequencies. Besides, the frequency sweeping is time-consuming, where a recalibration is needed for different sensor setups applied to the online real-time measurement. In this paper, a single-frequency algorithm has been proposed, which is embedded in the measurement instrument for the online real-time retrieval of thickness. Owing to the single-frequency measurement strategy, the proposed method does not need to recalibrate for different sensor setups. The thickness retrieval is based on a triple-coil sensor (with one transmitter and two receivers). The thickness of metallic disk foils is retrieved from the measured electrical resistance of two transmitter-receiver sensing pairs. Experiments on materials of different electrical conductivities (from direct current), thicknesses and planar sizes (radii) have been carried out to verify the proposed method. The error for the thickness retrieval of conductive disk foils is controlled within 5% for lift-offs up to 5 mm. [ABSTRACT FROM AUTHOR]

In the eddy current testing, the impedance tested by the sensor is influenced by the lift-off between the sensor and the sample plate. Consequently, the thickness inferred from the measured impedance is also affected by the lift-off. In this paper, a novel planar triple-coil air-core sensor is designed, in which three coils (two excitation coils and one receiving coil) with different radii are co-axially arranged in the same plane. Based on this sensor setup, an algorithm for the thickness measurement of the non-magnetic metallic plate is proposed. By using the transmitter-receiver combinations and the proposed algorithm, the measured thickness is almost immune to the lift-off variation. Moreover, previously the measurement of thickness requires a complex frequency feature – peak frequency for the real part of the impedance, which is obtained from the multi-frequency impedance or inductance spectra (frequency-sweeping mode), while with the method proposed in this paper, only single frequency measurement is needed, hence relaxing the instrument and measurement requirements. This method has a potential of on-line real-time measurement of the thickness for non-magnetic steel plates. [ABSTRACT FROM AUTHOR]