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Unlike optical waves, acoustic waves in fluids are described by scalar pressure fields, and therefore are considered spinless. Here, we demonstrate experimentally the existence of spin in acoustics. In the interference of two acoustic waves propagating perpendicularly to each other, we observed the spin angular momentum in free space as a result of the rotation of local particle velocity. We successfully measured the acoustic spin, and spin-induced torque acting on a designed lossy acoustic probe that results from absorption of the spin angular momentum. The acoustic spin is also observed in the evanescent field of a guided mode traveling along a metamaterial waveguide. We found spin-momentum locking in acoustic waves whose propagation direction is determined by the sign of spin. The observed acoustic spin could open a new door in acoustics and its applications for the control of wave propagation and particle rotation.

Background Delayed meningeal cyst (DMC) is a rare complication after spinal surgery that is often ignored by clinicians, and its in-depth research is infrequent. In particular, no consensus has been reached about its surgical treatment. We found that patients with a DMC failed after conservative treatment, epidural blood patch, subarachnoid drainage, and initial attempts to eliminate the meningeal cyst. Therefore, we introduce the application of a paraspinal muscle flap repair under a microscope for the treatment of DMC. Methods In this study, 13 patients who were repaired by a paraspinal muscle flap under a microscope for DMC from January 2007 to January 2017 were retrospectively reviewed. Their ages were 18–68 years old (mean age 48.7 years). The course of the disease ranged from 3 weeks to 28 months after the operation for the primary disease, with an average of 10.6 months. Length >5 cm was called a large DMC and length >8 was called a giant DMC. By analyzing the effect of surgical treatment, we summarized the treatment experience of DMC and evaluated the risk factors for the formation of DMC. Results All patients were treated with paraspinal muscle flap repair under a microscope, and they healed well after the operation. There was no cerebrospinal fluid leakage or other operation-related complication. The mean follow-up was 16.5 months. Reexamination of the spine MRI showed no recurrence of the DMC. Conclusions The application of paraspinal muscle flap under a microscope combined with glue, bedrest, and CSF drain, was an effective option for the patients with DMC.

Abstract Bearing‐only tracking of an underwater uncooperative target is essential to defend the sea territory. Considering the influences by uncertain underwater environment, the purpose of this work is to estimate 2‐D locations and velocities of an interested underwater target for non‐Gaussian environment. In this work, a fast particle filter (FPF) based on the traditional particle filter (PF) with novel jet transport (JT) technique is proposed to deal with this problem. Aiming to overcome the heavy computation burden of the traditional PF that limits most of its practical applications, the JT technique can dramatically reduce the computation time and complexity in the particle evolution process, which contributes huge computational complexities to the traditional PF. Then, the proposed FPF is tested through simulations in the 2‐D underwater uncooperative target tracking scenario. Finally, the Monte Carlo simulation results demonstrate that the proposed FPF can track the underwater uncooperative target with the similar accuracies as the traditional PF but only occupies less than 20% of the computational resources.

Abstract Enzymes have been known to impact the biofilm forming capacity. However, how the enzymes mediate the biofilm formation and macrofouling remains little known. Here, we investigated the effects of the three kinds of proteases, four kinds of glycosidases and one kind of lipase on the detachment of biofilms of Shewanella marisflavi ECSMB14101, identified biofilm total proteins response to enzyme treatments, and then tested the effects of biofilms treated with enzymes on the settlement of the mussel Mytilus coruscus plantigrades. The results showed that the cell density of bacteria in biofilms formed at different initial bacterial density were noticeably reduced after treating with all tested enzymes, and Neutrase and α-Amylase exhibited best removing efficiency of > 90%. Bacterial total proteins in S. marisflavi biofilm noticeably reduced or disappeared after treated by Alcalase. For the settlements of the mussel M. coruscus plantigrades, inducing capacities of S. marisflavi biofilm were noticeably suppressed and downregulation was > 75% at the initial density of 5 × 106 cells/cm2. Thus, the tested enzymes could effectively remove the adhered bacterial cell, inhibit the biofilm formation and finally suppress the mussel settlement. Our findings extend novel knowledge to developing eco-friendly approach to control micro- and macro-fouling.

BackgroundIschemic Heart Disease (IHD) is the leading cause of death from cardiovascular disease. Currently, most studies have focused on factors influencing IDH or mortality risk, while few predictive models have been used for mortality risk in IHD patients. In this study, we constructed an effective nomogram prediction model to predict the risk of death in IHD patients by machine learning.MethodsWe conducted a retrospective study of 1,663 patients with IHD. The data were divided into training and validation sets in a 3:1 ratio. The least absolute shrinkage and selection operator (LASSO) regression method was used to screen the variables to test the accuracy of the risk prediction model. Data from the training and validation sets were used to calculate receiver operating characteristic (ROC) curves, C-index, calibration plots, and dynamic component analysis (DCA), respectively.ResultsUsing LASSO regression, we selected six representative features, age, uric acid, serum total bilirubin, albumin, alkaline phosphatase, and left ventricular ejection fraction, from 31 variables to predict the risk of death at 1, 3, and 5 years in patients with IHD, and constructed the nomogram model. In the reliability of the validated model, the C-index at 1, 3, and 5 years was 0.705 (0.658–0.751), 0.705 (0.671–0.739), and 0.694 (0.656–0.733) for the training set, respectively; the C-index at 1, 3, and 5 years based on the validation set was 0.720 (0.654–0.786), 0.708 (0.650–0.765), and 0.683 (0.613–0.754), respectively. Both the calibration plot and the DCA curve are well-behaved.ConclusionAge, uric acid, total serum bilirubin, serum albumin, alkaline phosphatase, and left ventricular ejection fraction were significantly associated with the risk of death in patients with IHD. We constructed a simple nomogram model to predict the risk of death at 1, 3, and 5 years for patients with IHD. Clinicians can use this simple model to assess the prognosis of patients at the time of admission to make better clinical decisions in tertiary prevention of the disease.

BackgroundThere is only limited evidence for an association between calcium (Ca) and depression, and the relationship was inconsistent. Therefore, the aim of this study was to assess the relationship between dietary Ca and the risk of depressive symptoms in individuals over the age of 18 in the US.MethodsWe extracted 14,971 participants from the US National Health and Nutrition Examination Survey (NHANES) 2007–2016 to probe their associations. Dietary Ca intake was measured through 24 h dietary recall method. Patients with the Patient Health Questionnaire-9 (PHQ-9) ≥ 10 scores were believed to have depressive symptoms. The association between dietary Ca and depressive symptoms was investigated using multivariate logistic regression, sensitivity analysis, and restricted cubic spline regression.ResultsIn this study, 7.6% (1,144/14,971) of them had depressive symptoms. After adjusting for sex, age, race, poverty to income ratio (PIR), marital status, education, body mass index (BMI), caffeine intake, carbohydrates intake, total energy intake, smoking status, alcohol consumption, physical activity, diabetes, hypertension, severe cardiovascular disease (CVD), cancer, serum vitamin D, serum Ca, and Ca supplement, the adjusted ORs value [95% confidence interval (CI)] of depression for the lowest category (Q1 ≤ 534 mg/day) vs. Q2–Q4 of Ca intake were 0.83 (0.69–0.99), 0.97 (0.65–0.95), and 0.80 (0.63–0.98) with the p for trend (p = 0.014). The relationship between dietary Ca intake and depressive symptoms was linear (non-linear p = 0.148). None of the interactions were significant except among races (p for interaction = 0.001).ConclusionAssociation between dietary Ca and the prevalence of depressive symptoms in US adults. And Ca intake was negatively associated with the risk of depressive symptoms. As Ca intake increased, the prevalence of depressive symptoms decreased.

BackgroundIschemic heart disease (IHD) has a high mortality in the population. Although serum creatinine (Cr) and serum total bilirubin (TBil) are rapid and readily available biomarkers in routine blood tests, there is a lack of literature on the prognostic value of combined Cr and TBil tests for IHD. This study aimed to evaluate a combined equation based on Cr and TBil to predict the long-term risk of death in IHD and to find indicators sensitive to the prognosis of IHD patients.MethodIn this study, 2625 patients with IHD were included, and the combined value and combined equations of Cr and TBil were obtained by logistic regression analysis based on Cr and TBil collected at the time of admission. Patients were divided into four groups according to the quartiles of the combined value. COX proportional hazard regression model was used to analyze the risk factors for long-term death in IHD patients. Receiver operating characteristic (ROC) curves were used to evaluate the prognostic effect of Cr, TBil and combined value on long-term death events.ResultsLogistic regression analysis was performed for long-term death events with Cr and TBil as independent variables, and the logit regression model was Logit(P) = 0.0129×TBil+0.007×Cr-0.417. Multifactorial Cox regression analysis showed that high values of the equation were independent risk factors for long-term death events (all-cause death: HR 1.457, 95% CI 1.256-1.689, PConclusionCombined Cr and TBil assay is superior to single biomarkers for predicting long-term death in patients with IHD. High values of the equation are independent predictors of long-term death and can be used to identify patients at high risk for IHD.

Finishing weight is a key economic trait in the domestic pig industry. Evidence has linked the gut microbiota and SCFAs to health and production performance in pigs. Nevertheless, for Diannan small ear (DSE) pigs, a specific pig breed in China, the potential effect of gut microbiota and SCFAs on their finishing weight remains unclear. Herein, based on the data of the 16S ribosomal RNA gene and metagenomic sequencing analysis, we found that 13 OTUs could be potential biomarkers and 19 microbial species were associated with finishing weight. Among these, carbohydrate-decomposing bacteria of the families Streptococcaceae, Lactobacillaceae, and Prevotellaceae were positively related to finishing weight, whereas the microbial taxa associated with intestinal inflammation and damage exhibited opposite effects. In addition, interactions of these microbial species were found to be linked with finishing weight for the first time. Gut microbial functional annotation analysis indicated that CAZymes, such as glucosidase and glucanase could significantly affect finishing weight, given their roles in increasing nutrient absorption efficiency. Kyoto Encyclopedia of Genes and Genomes (KEGG) Orthologies (KOs) and KEGG pathways analysis indicated that glycolysis/gluconeogenesis, phosphotransferase system (PTS), secondary bile acid biosynthesis, ABC transporters, sulfur metabolism, and one carbon pool by folate could act as key factors in regulating finishing weight. Additionally, SCFA levels, especially acetate and butyrate, had pivotal impacts on finishing weight. Finishing weight-associated species Prevotella sp. RS2, Ruminococcus sp. AF31-14BH and Lactobacillus pontis showed positive associations with butyrate concentration, and Paraprevotella xylaniphila and Bacteroides sp. OF04-15BH were positively related to acetate level. Taken together, our study provides essential knowledge for manipulating gut microbiomes to improve finishing weight. The underlying mechanisms of how gut microbiome and SCFAs modulate pigs’ finishing weight required further elucidation.

Marine invertebrates are the backbone of marine biodiversity and play a pivotal role in the marine ecosystem. The life cycle of most marine invertebrates includes the settlement and metamorphosis stage, which is induced by marine biofilms, but the mechanism is still enigmatic. In the present study, we constructed the capsular polysaccharide (CPS) synthesis gene capC-deleted mutant of Pseudoalteromonas marina by gene knockout and then compared the phenotype, the biofilm-forming ability, the effect on settlement and metamorphosis of Mytilus coruscus, and the exopolysaccharide and CPS levels between the mutant and the wild-type strains to explicate the relationship between bacteria and mussels. The study presented that the phenotype and biofilm-forming ability between the wild-type and ΔcapC strains had no significant difference, but the inducing activity of ΔcapC biofilms on larval settlement and metamorphosis decreased significantly (p < 0.05). Compared with the wild-type, the CPS content of ΔcapC strain significantly decreased by 38.07%, accompanied by the increase of c-di-GMP. Meanwhile, the biomass of α-polysaccharides and β-polysaccharides on ΔcapC biofilms decreased significantly (p < 0.05). Thus, the CPS synthesis gene could modulate c-di-GMP, which regulates bacterial polysaccharide secretion, and then impact larval settlement and metamorphosis of mussels. This work brings an entry point to deeply understand the interaction between bacterial polysaccharide and larval recruitment.

Abstract Cervical cancer metastasis is an important cause of death in cervical cancer. Previous studies have shown that epithelial–mesenchymal transition (EMT) of tumors promotes its invasive and metastatic capacity. Alterations in the extracellular matrix (ECM) and mechanical signaling are closely associated with cancer cell metastasis. However, it is unclear how matrix stiffness as an independent cue triggers EMT and promotes cervical cancer metastasis. Using collagen‐coated polyacrylamide hydrogel models and animal models, we investigated the effect of matrix stiffness on EMT and metastasis in cervical cancer. Our data showed that high matrix stiffness promotes EMT and migration of cervical cancer hela cell lines in vitro and in vivo. Notably, we found that matrix stiffness regulates yes‐associated protein (YAP) activity via PPIase non‐mitotic a‐interaction 1 (Pin1) with a non‐Hippo mechanism. These data indicate that matrix stiffness of the tumor microenvironment positively regulates EMT in cervical cancer through the Pin1/YAP pathway, and this study deepens our understanding of cervical cancer biomechanics and may provide new ideas for the treatment of cervical cancer.

The reactivation mechanism of old landslides has been extensively studied from building load, erosion of the slope toe, heavy rainfall, and slope cutting for existing research. However, previous research on the reactivation of old landslides pays little attention to the combined action of engineering disturbance and heavy rainfall is rarely studied. This paper describes an old landslide in Wushan County, Chongqing, China, that was reactivated in August 2019 due to engineering disturbance and heavy rainfall. The deformation of the old landslide was first observed in 2007 and 2008, resulting from excavation and rainfall, respectively, and remained stable for about 11 years after treatment. In August 2019, the landslide was reactivated by slope cutting and damaged anti-sliding piles at the toe, and entered a state of imminent sliding due to the concentrated heavy rainfall events that occurred from October 4 to 22, 2019. In order to reveal the deformation features and reactivation mechanism of the landslide, field investigations, drilling activities and monitoring were performed. The results showed that tectonic effects and the stratigraphic lithology were the main reasons for the formation of the old Dashuitian landslide. The cut slope and damaged anti-sliding piles at the toe of the landslide provided the sliding space and reduced the anti-sliding force, and therefore resulted in the reactivation of the landslide. Continuous intense rainfall increased the weight of the landslide, decreased the mechanical properties and increased the pore water pressure of the weak interlayer, which accelerated the deformation rate. Therefore, 1.5 million m3 of rock and soil masses slid along the weak interlayer under the action of gravity, threatening the safety of Wuliu Road, Ring Road, National Road G42 and the Wu-Da Expressway. Our research provides a theoretical basis for reducing the hazard of similar engineering projects involving slopes.

Most studies of the effects of urbanisation on local climate have been based on ground observation data. In contrast, we used observation data from a boundary layer radar wind profiler, radio-acoustic sounding system, and automatic meteorological station located at Shenzhen Bao’an International Airport to analyse changes in wind and virtual temperature in the upper level atmosphere, with a top height of 1,200 m, over the Pearl River Estuary between 2011 and 2020. Our results show that during the decade evaluated, the wind speed and virtual temperature of the upper level atmosphere over the Pearl River Estuary changed very significantly and faster than the changes observed at ground level. During the study period, the linear warming rate of the virtual temperature of the upper level atmosphere reached 0.24°C/a, whereas that on the land surface was 0.17°C/a. The mean decreases in the upper level atmosphere and land surface wind speeds were −0.12 and −0.05 m/s·a, respectively. Additionally, the rate of change in the upper level climate was faster in winter than in summer for both wind speed and virtual temperature. These changes in the climate of the upper level atmosphere over the Pearl River Estuary may be related to the rapid increase in the number of high-rise buildings in the region during that decade, which generally negatively affected the atmospheric environment.

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While changes in Chinese Communist Party (CCP) recruitment are generally described as different phases focused on recruiting either “reds” or “experts,” giving more or less weight to political or technical criteria, we instead stress the importance of changing understandings of political loyalty to examine these evolutions. By tracing these changes throughout the party's 100 years, we show that how the party understands loyalty is largely strategic, detached from a purely ideological approach. The CCP has alternatively approached loyalty in ascriptive terms, based on class background, and behavioural ones, looking at active displays of loyalty or passive obedience. The level and form of activism expected from party members and cadres have also dramatically changed over time. Relying on recruitment data, this article shows that it is paradoxically during periods of party expansion that the CCP becomes more politically demanding with its members.

β-N-acetylhexosaminidases (EC3.2.1.52), which belong to the glycosyl hydrolase family GH20, are important enzymes for oligosaccharides modification. Numerous microbial β-N-acetylhexosaminidases have been investigated for applications in biology, biomedicine and biotechnology. Akkermansia muciniphila is an anaerobic intestinal commensal bacterium which possesses specific β-N-acetylhexosaminidases for gut mucosal layer colonization and mucin degradation. In this study, we assessed the in vitro mucin glycan cleavage activity of the A. muciniphila β-N-acetylhexosaminidase Am2136 and demonstrated its ability that hydrolyzing the β-linkages joining N-acetylglucosamine to a wide variety of aglycone residues, which indicated that Am2136 may be a generalist β-N-acetylhexosaminidase. Structural and enzyme activity assay experiments allowed us to probe the essential function of the inter-domain interactions in β23-β33. Importantly, we revealed that the hydrolysis activity of Am2136 was enhanced by nucleotides. We further speculated that this activation mechanism might be associated with the conformational motions between domain III and IV. To our knowledge, this is the first report of nucleotide effector regulated β-N-acetylhexosaminidase, to reveal its novel biological functions. These findings contribute to understanding the distinct properties within the GH20 family and lay a certain foundation to develop controllable glycan hydrolyzing catalysts.Abbreviations: OD600 - optical cell densities at 600 nm; LB - Luria–Bertani; IPTG - isopropyl β-D-1-thiogalactopyranoside; PMSF - phenylmethanesulfonyl fluoride; rmsd - root mean square deviation; GlcNAc - N-acetyl-β-D-glucosamine; GalNAc - N-acetyl-β-D-galactosamine; Gal - galactose

Abstract Background Long non-coding RNAs (lncRNAs) play a crucial role in diverse biological processes and have been confirmed to be concerned with various diseases. Largely uncharacterized of the physiological role and functions of lncRNA remains. MicroRNAs (miRNAs), which are usually 20–24 nucleotides, have several critical regulatory parts in cells. LncRNA can be regarded as a sponge to adsorb miRNA and indirectly regulate transcription and translation. Thus, the identification of lncRNA-miRNA associations is essential and valuable. Results In our work, we present DWLMI to infer the potential associations between lncRNAs and miRNAs by representing them as vectors via a lncRNA-miRNA-disease-protein-drug graph. Specifically, DeepWalk can be used to learn the behavior representation of vertices. The methods of fingerprint, k-mer and MeSH descriptors were mainly used to learn the attribute representation of vertices. By combining the above two kinds of information, unknown lncRNA-miRNA associations can be predicted by the random forest classifier. Under the five-fold cross-validation, the proposed DWLMI model obtained an average prediction accuracy of 95.22% with a sensitivity of 94.35% at the AUC of 98.56%. Conclusions The experimental results demonstrated that DWLMI can effectively predict the potential lncRNA-miRNA associated pairs, and the results can provide a new insight for related non-coding RNA researchers in the field of combing biology big data with deep learning.

Abstract Background Our research was designed to decide whether the application of C2 pars screws is an alternative choice for patients with OPLL involving the C2 segment. Methods A total of 40 patients who underwent cervical laminectomy with fusion (LF) from C2 to C6 for OPLL were reviewed. Among them, C2 pedicle screws were placed in 23 patients, who were the pedicle group, and C2 pars screws were placed in 17 patients, who were the pars group. The screw placement and vertebral artery (VA) anatomy presented by standard CT. General clinical characteristics and health-related outcomes were evaluated and compared preoperatively and during the follow-up period. Results The Pars group tended to have a shorter operation duration and less blood loss than the pedicle group (operation time: 115.29 ± 28.75 vs 133.48 ± 26.22, p = 0.044; blood loss: 383.53 ± 116.19 vs 457.83 ± 145.45, p = 0.039). Operation time and blood loss were both independently related to the pars group (operation time: OR = 0.966, p = 0.021; blood loss: OR = 0.993, p = 0.046). The idealization and acceptability of C2 screws in the pars group exceeded those in the pedicle group (100% vs 91.3%). However, no statistically obvious variation in the included complications or health-related outcomes between the pedicle and pars groups was observed. Conclusion In the treatment of patients with OPLL involving the C2 segment, the application of C2 pars screws is an alternative choice, which is not only safer but also reduces the amount of blood loss, shortens the operation time and obtains a more ideal screw placement.

This paper proposes a compact $4 \times 4$ filtering microstrip patch antenna array with Dolph- Chebyshev distribution implemented by multilayer structure. The proposed antenna array features good filtering performance but contains no extra filtering parts in the feeding or the radiating element. The whole antenna array consists of four $1 \times 4$ antenna subarrays, each subarray is composed of four patch antennas which are coupled-fed by a single microstrip line. Inside the desired passband, by properly choosing the coupling area along the microstrip line, the patches are induced in-phase currents therefore achieving the excellent radiation characteristics. On the other hand, the four patches can’t be properly excited outside the passband which would enable radiation suppression performance. In order to implement a $4 \times 4$ filtering microstrip patch antenna array with low sidelobe level (SLL), four subarrays are combined and fed by Dolphy-Chebyshev excitation method. Finally, the proposed antenna array is implemented, fabricated and measured. The maximum measured gain in the passband is 14.7 dBi, and the radiation suppression outside the passband is better than 25 dB.

Inflammatory responses, including glial cell activation and peripheral immune cell infiltration, are involved in the pathogenesis of Parkinson’s disease (PD). These inflammatory responses appear to be closely related to the release of extracellular vesicles, such as exosomes. However, the relationships among different forms of glial cell activation, synuclein dysregulation, mitochondrial dysfunction, and exosomes are complicated. This review discusses the multiple roles played by exosomes in PD-associated inflammation and concludes that exosomes can transport toxic α-synuclein oligomers to immature neurons and into the extracellular environment, inducing the oligomerization of α-synuclein in normal neurons. Misfolded α-synuclein causes microglia and astrocytes to activate and secrete exosomes. Glial cell-derived exosomes participate in communications between glial cells and neurons, triggering anti-stress and anti-inflammatory responses, in addition to axon growth. The production and release of mitochondrial vesicles and exosomes establish a new mechanism for linking mitochondrial dysfunction to systemic inflammation associated with PD. Given the relevance of exosomes as mediators of neuron-glia communication in neuroinflammation and neuropathogenesis, new targeted treatment strategies are currently being developed that use these types of extracellular vesicles as drug carriers. Exosome-mediated inflammation may be a promising target for intervention in PD patients.