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In unstructured environments, dense grape fruit growth and the presence of occlusion cause difficult recognition problems, which will seriously affect the performance of grape picking robots. To address these problems, this study improves the YOLOX-Tiny model and proposes a new grape detection model, YOLOX-RA, which can quickly and accurately identify densely growing and occluded grape bunches. The proposed YOLOX-RA model uses a 3 × 3 convolutional layer with a step size of 2 to replace the focal layer to reduce the computational burden. The CBS layer in the ResBlock_Body module of the second, third, and fourth layers of the backbone layer is removed, and the CSPLayer module is replaced by the ResBlock-M module to speed up the detection. An auxiliary network (AlNet) with the remaining network blocks was added after the ResBlock-M module to improve the detection accuracy. Two depth-separable convolutions (DSC) are used in the neck module layer to replace the normal convolution to reduce the computational cost. We evaluated the detection performance of SSD, YOLOv4 SSD, YOLOv4-Tiny, YOLO-Grape, YOLOv5-X, YOLOX-Tiny, and YOLOX-RA on a grape test set. The results show that the YOLOX-RA model has the best detection performance, achieving 88.75 % mAP, a recognition speed of 84.88 FPS, and model size of 17.53 MB. It can accurately detect densely grown and shaded grape bunches, which can effectively improve the performance of the grape picking robot.

Abstract Visual localization for mobile robots is a sophisticated and challenging task that necessitates the extraction of pertinent scene information from images obtained by the robot’s visual sensors to ascertain its position within an environment. The task is complicated by variations in environmental factors which affect the accuracy of localization. To address the challenges of visual localization on variations of illumination, seasons, and viewpoints, this paper proposes a visual localization network based on a gated selection and hybrid receptive field. We utilize a fine-tuned DINOv2 for local feature extraction and leverage a hybrid receptive field to enhance the diversity of visual features. Furthermore, our approach employs spatial gating to dynamically and effectively select and aggregate the advantageous spatial features. Extensive experiments demonstrate that the visual localization performance of our approach surpasses existing methods on multiple challenging datasets, particularly achieving a Recall@1 metric of 69.2% on the NordLand dataset, which signifies a 10.8% enhancement compared to MixVPR.

Abstract Polyimides have emerged as promising dielectric materials for communication equipment, owing to their excellent thermal stability and processability. Nonetheless, a pressing need remains to reduce the high-frequency dissipation factor (D f) of polyimides. Here, we synthesized various polyimides featuring linear backbone structures, finding that polyimides that incorporate a combination of ester groups and ether bonds exhibit low D f values of 0.0015-0.0024 at 10 GHz. Even in high humidity and temperature conditions they maintain low D f values of

Abstract Nursing students, who comprise a high percentage of China’s college students, experience many psychological problems; however, few studies explored the mechanisms underlying these problems. This cross-sectional study explored the relationships and mechanisms of depression, anxiety, stress, and narrative disorders in senior nursing students. Questionnaires were administered to 380 senior nursing students in Hubei Province using the Sociodemographic Questionnaire, Toronto Alexithymia-20 Scale, Perceived Social Support Scale, 10-Item Connor-Davidson Resilience Scale, and Depression-Anxiety-Stress Scale. After controlling for sociodemographic variables, Hayes’ PROCESS macros were used to test how psychological resilience moderates the relationships among narrative disorders, negative affect, and perceived social support. Bootstrap confidence intervals tested for indirect effects. Correlation analyses revealed that alexithymia was correlated significantly positively with depression-anxiety-stress (r = 0.57, 0.56, and 0.58, resp.) and significantly negatively with perceived social support (r = 0-0.46). Psychological resilience was correlated significantly negatively with alexithymia (r=-0.39) and depression-anxiety-stress (r=-0.31, -0.30, and-0.32, resp.) but significantly positively with perceived social support(r = 0.50). Perceived social support was correlated significantly negatively with depression-anxiety-stress (r=-0.33, -0.34, and − 0.42 resp.). Stress was correlated significantly positively with anxiety and depression (r = 0.81 and 0.77, resp.). Psychological resilience was a partial mediator between depression and dysphoria (β=-0.08, p

Streptococcus is one of the common pathogens of suppurative infections. Invasive group A Streptococcus (iGAS) infections often develop from skin or soft tissue infections, and streptococcal toxic shock syndrome is considered the main cause of death in Chinese children with iGAS infectious disease. However, soft tissue infections caused by iGAS infections, especially the formation of abscesses, are relatively rare. A retrospective study was conducted, and pediatric in-patients who were diagnosed with an iGAS infection identified by cultures from normally sterile sites and treated in a tertiary hospital during 2016–2018 were included. A total of 14 patients were identified, which included 10 boys and four girls. The patients had an age range from 3 months to 10 years and were diagnosed with soft tissue infections and a formation of abscesses caused by iGAS infections. The most common sites of infections were the lower limbs. In five patients, the abscess was accompanied by fever, and the local soft tissue showed redness, swelling, tenderness, and an elevated skin temperature. Laboratory findings included an increased white blood cell (WBC) count in 12 patients, an increased C reactive protein (CRP) level in seven patients, and an increased erythrocyte sedimentation rate (ESR) in 10 patients. No patients had an elevated procalcitonin level. For all 14 patients, we performed puncture and drainage of abscesses, and cultured GAS from the drainage fluid. All children also received antibiotic treatment. During 2 months of follow-up, the patients' condition remained stable and no evidence of kidney or heart damage was observed. For pediatric patients with abscesses, early diagnosis, prompt treatment with incision and drainage, and immediate culture of the drainage fluid are important. Upon confirmation of an iGAS infection, β-lactam antibiotics should be given to provide effective treatment, and in some patients with poor therapeutic outcomes, the use of vancomycin as an alternative can achieve the desired results.

Abstract Although Dynamic Movement Primitives (DMP) is an effective tool for robotic arm trajectory generalisation, the application of DMP in the 3C (Computer, Communication, Consumer Electronics) industry still faces challenges such as low precision and high‐time consumption. To address this problem, we propose a novel Cauchy DMP framework. The main improvements and advantages of Cauchy DMP, compared to the original DMP, are (1) since the Cauchy distribution has a simpler model and wider shape, using the Cauchy distribution instead of the Gaussian distribution in the original DMP reduces the complexity of the algorithm and saves time. (2) Singular Value Decomposition (SVD) can effectively model the error. To reduce the interference of the rounding and human error on the trajectory, SVD can be used to obtain the weight of each basis function. The proposed Cauchy DMP framework combines the above two points and is validated on a real UR5 robotic arm. The results show that Cauchy DMP retains the learnability of the original DMP and has the advantages of short time consumption and low error rate.

Abstract As a living repair material, cell sheet exhibits significant potential in wound repair. Nonetheless, wound healing is a complicated and protracted process that necessitates specific repair functions at each stage, including hemostasis and antibacterial activity. In this work, on the basis of harvesting the cell sheet via a photothermal response strategy, a fibronectin attached cell sheet (FACS) is prepared to enhance its wound repair capability. For this purpose, the azide group (N3) is initially tagged onto the cell surface through metabolic glycoengineering of unnatural sugars, and then the conjugate (DBCO‐fibronectin) comprises of the dibenzocyclooctyne (DBCO) and fibronectin with multiple wound repair functions is linked to N3 using click chemistry. Biological evaluations following this demonstrates that the FACS preparation exhibits excellent biocompatibility, and the fibronectin modification enhances the capacity for cell proliferation and migration. Moreover, in vivo wound healing experiment confirms the reparative efficacy of FACS. It not only has a wound closure rate 1.46 times that of a conventional cell sheet but also reduces inflammatory cell infiltration, promotes hair follicle and blood vessel regeneration, and encourages collagen deposition. This strategy holds enormous clinical potential and paves the way for advanced functional modifications of cell sheets.

BackgroundMandibuloacral dysplasia (MAD) syndrome is a rare genetic disease. Several progeroid syndromes including mandibuloacral dysplasia type A (MADA), mandibuloacral dysplasia type B(MADB), Hutchinson-Gilford progeria (HGPS) and mandibular hypoplasia, deafness, and lipodystrophy syndrome (MDPL) have been reported previously. A novel MAD progeroid syndrome (MADaM) has recently been reported. So far, 7 cases of MADaM diagnosed with molecular diagnostics have been reported in worldwide. In the Chinese population, cases of MAD associated with the MTX2 variant have never been reported.MethodsThe clinical symptoms and the genetic analysis were identified and investigated in patients presented with the disease. In addition, we analyzed and compared 7 MADaM cases reported worldwide and summarized the progeroid syndromes reported in the Chinese population to date.ResultsThe present study reports a case of a novel homozygous mutation c.378 + 1G > A in the MTX2 gene, which has not been previously reported in the literature. Patients present with early onset and severe symptoms and soon after birth are found to have growth retardation. In addition to the progeroid features, skeletal deformities, generalized lipodystrophy reported previously, and other multisystem involvement, e.g. hepatosplenic, renal, and cardiovascular system, this case was also reported to have combined hypogammaglobulinemia. She has since been admitted to the hospital several times for infections. Among 22 previously reported progeroid syndromes, 16/22 were MADA or HGPS caused by LMNA gene mutations, and the homozygous c.1579C > T (p.R527C) mutation may be a hot spot mutation for MAD in the Chinese population. MAD and HGPS mostly present in infancy with skin abnormalities or alopecia, MDPL mostly presents in school age with growth retardation as the first manifestation, and is often combined with an endocrine metabolism disorder after several decades.ConclusionThis is the first case of MAD syndrome caused by mutations in MTX2 gene reported in the Chinese population. MTX2 gene c.378 + 1G > A homozygous mutation has not been previously reported and the report of this patient expands the spectrum of MTX2 mutations. In addition, we summarized the genotypes and clinical characteristics of patients with progeroid syndromes in China.

The highly mature light oil from well Shunnan 1 in the Guchengxu Uplift, Tarim Basin is considered to be a typical residual oil by thermal cracking. The study reveals that the abundant monoaromatic hydrocarbons and polynuclear aromatics in the crude oil of well Shunnan 1 are the by-products of severe in-reservoir oil-cracking during the geological history. The monoaromatic hydrocarbons are the intermediate products of thermal cracking, cyclization and aromatization, while the polynuclear aromatics are indicative of polycondensation reaction. The strong carbon isotopic fractionation induced by hydrocarbon molecule cracking and polycondensation makes the molecule carbon isotope of n-alkanes and the molecule carbon isotope of alkyl naphthalenes in the crude oil of well Shunnan 1 respectively 8‰-10‰ and 6‰-8‰ heavier compared to those from unaltered crude oils in Lower Paleozoic oil-bearing system. The results further proved that the aromatic molecules related to oil cracking and their stable carbon isotopic compositions could be a potentially powerful tool to identify whether thermal alteration occurred in deep and ultra-deep oil reservoirs, and further helps to effectively evaluate the oil and gas phase and resource pattern in the deep and ultra-deep reservoirs.

Vacuum brazing of GH3535 alloy was conducted using Au–18Ni (wt%) filler metal. The effect of brazing temperature on the microstructure and mechanical properties was investigated. Furthermore, the microstructural evolution and fracture mechanisms of brazed joints were discussed. The cross section of brazed joint could be divided into two distinctive reaction zones. The typical microstructure of the joint brazed at 1030 °C/10min was GH3535 substrate/Ni (s.s) + Mo-rich Ni (s.s) + Au-rich phase/Au (s.s) + FeNi3/Au-rich phase + Mo-rich Ni (s.s) + Ni (s.s) + GH3535 substrate. Raising the brazing temperature promoted the diffusion of elements, Ni (s.s) and Au (s.s) gradually increased, and the second phase particles consisting of FeNi3 gradually decreased. With the increase in brazing temperature, the shear strength of brazed joints first increased and then decreased. The maximum room shear strength of 420 MPa was obtained at 960 °C/25min and the high temperature shear strength of 153 MPa was obtained at 600 °C. Fracture analysis indicated that cracks initiated at the interface of Au (s.s) and then propagated along the zone of FeNi3 with dimple and tearing ridges patterns.

Abstract Macroscopic chiral spherulites prepared by hierarchical self‐assembly have attracted considerable attention due to their excellent property as chiroptical materials. However, preparing controllable chiral spherulites in bulk film remains a challenge due to the absent knowledge of the evolution mechanism from the molecule to macroscopic crystal during chiral assembly. In this contribution, chiral macroscopic spherulites were constructed with controllable circularly polarized luminescence (CPL) using enantiomeric tartaric acid and rhodamine B co‐assembled with liquid crystal block copolymers, poly(ethylene oxide)‐b‐poly(methyl methacrylate) bearing azobenzene group side chains. It was found that the chiral liquid crystal field induced by exogenous chiral molecules was closely related to the formation of macroscopic chiral spherulites. Moreover, the transformation of azobenzene cis‐trans isomerization under photo‐thermal endows films with adjustable CPL. This facile strategy provides a platform to design large‐scale chiral structures for chiroptical switching, encryption, and memory storage materials.

Obstructive sleep apnea (OSA) is a common syndrome characterized by upper airway dysfunction during sleep. Continuous positive airway pressure (CPAP) is the most frequently utilized non-surgical treatment for OSA. Ferroptosis play a crucial role in the physiological diseases caused by chronic intermittent hypoxia, but its involvement in the development of OSA and the exact mechanisms have incompletely elucidated. GSE75097 microarray dataset was used to identify differentially expressed genes between OSA patients and CPAP-treated OSA patients. Subsequently, Gene Ontology (GO) annotation, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, STRING database, and FerrDb database were conducted to analyze the biological functions of differentially expressed genes and screen ferroptosis-related genes. Finally, GSE135917 dataset employed for validation. There were 1,540 differentially expressed genes between OSA patients and CPAP-treated OSA patients. These differentially expressed genes were significantly enriched in the regulation of interleukin-1-mediated signaling pathway and ferroptosis-related signaling pathway. Subsequently, 13 ferroptosis-related genes (DRD5, TSC22D3, TFAP2A, STMN1, DDIT3, MYCN, ELAVL1, JUN, DUSP1, MIB1, PSAT1, LCE2C, and MIR27A) were identified from the interaction between differentially expressed genes and FerrDb database, which are regarded as the potential targets of CPAP-treated OSA. These ferroptosis-related genes were mainly involved in cell proliferation and apoptosis and MAPK signaling pathway. Furthermore, DRD5 and TFAP2A were downregulated in OSA patients, which showed good diagnostic properties for OSA, but these abnormal signatures are not reversed with short-term effective CPAP therapy. In summary, the identification of 13 ferroptosis-related genes as potential targets for the CPAP treatment of OSA provides valuable insights into the development of novel, reliable, and accurate therapeutic options.

The electrochemical supercapacitors with high power density, long cycle life, and excellent safety represent one of the most promising energy storage devices for flexible and portable electronics, but their spontaneously rapid drop of open‐circuit voltage (self‐discharge) greatly limits their wide applications. Herein, a series of bilayer heterogeneous polyelectrolyts (BHPs) consisting of a polyanion complex and a polycation complex are designed, to regulate the self‐discharge performance of supercapacitors. The BHP‐based supercapacitors possess comparable energy storage properties with those of devices based on traditional homogeneous polymer electrolyte, but exhibit a unique and noteworthy suppressed effect on the self‐discharge performance of devices. The experimental results and theoretical simulation reveal that the zeta potential difference between the used polyanion/polycation complexes has effect on the self‐discharge rate of BHP‐based supercapacitor, and the electrostatic interaction between polyelectrolytes and the mobile counterions also greatly affects the self‐discharge performance of devices. Herein, the effect of molecular structures and their interaction of polyelectrolyte complexes in BHPs on the electrochemical performance of the resultant supercapacitors are systemmatically investigated, which provides a general strategy to design novel polymer electrolytes to build high‐performance flexible supercapacitors with long self‐discharge time.

Actively transitioning between clamping and grasping is a challenging problem for most manipulators with limited degrees of freedom. To overcome this problem, a cable-driven rigid–flexible combined manipulator capable of actively transitioning between clamping and grasping is proposed in this paper, which has a certain adaptability and compliance to achieve adaptive operation. First, the cable-driven unit and compliant unit of the cable-driven rigid–flexible combined manipulator are designed. Then, the sensitivity of the mechanism parameters is analyzed using the Monte Carlo method, and then the structure of the cable-driven rigid–flexible combined manipulator is optimized. After that, the force on the finger in two-point clamping mode is modelled using Newton’s second law. Furthermore, the input–output relationship modelling of the finger in envelope grasping mode is deeply analyzed using the principle of energy conservation. Finally, the stable grasping performance of the cable-driven rigid–flexible combined manipulator is verified using numerical simulation and physical prototype tests. The results show that the cable-driven rigid–flexible combined manipulator has good adaptability and compliance, which verifies the effectiveness and rationality of the design and modelling.

In the present work, the combination of shot peening (SP), low-temperature plasma nitriding (PN) and arc deposition (AD) is proposed to improve the wear performance of Ti6Al4V alloy. The low-temperature rapid nitriding of Ti6Al4V alloy was realized by SP pretreatment to obtain a desired nitrided interlayer. The high-density structural defects produced by SP pretreatment promote the nitriding kinetics at low temperature. The nitrided interlayer consists of an outermost TiN/Ti2N compound layer and an inner diffusion layer, showing a diffusion-typed hardness-profile, which is beneficial for the enhancing of adhesion strength and load-bearing capacity. Moreover, the improvement of adhesion strength is associated closely with TiN/Ti2N compounds which can provide heterogeneous nucleation sites for AD coating with a high hardness of about 3100 HV. The high bearing-load capacity and adhesion strength can ensure the excellent wear resistance of SP-PN-AD-coated sample when compared to single AD or PN-AD samples, especially under intensive wear load conditions. The present work provides a new insight into surface hardening of Ti alloys.

IntroductionThe incidences of acute rheumatic fever (ARF) and rheumatic heart disease (RHD), which were leading causes of death in children in the 1920s, have decreased substantially. Considering the recent resurgence of scarlet fever and increased incidence of streptococcal pharyngitis in children, an investigation of the current status of ARF and RHD may be worthwhile.ObjectiveTo summarize the prevalence trends, pathogenic factors, and prevention strategies for ARF and RHD in children.MethodsA selective search of literature published between January 1920 and February 2023 was done in PubMed, using the terms “acute rheumatic fever”, “rheumatic heart disease”, “group A Streptococcus”, “pharyngitis”, “pharyngeal tonsillitis”, “scarlet fever”, “impetigo”, “obstructive sleep apnea syndrome” and “child”.ResultsOvercrowded homes and inadequate sanitation led to recurrent group A streptococcal infection, and the causal relationship between group A streptococcal infection and ARF/RHD was well established. Streptococcal infectious diseases, such as group A streptococcal pharyngeal tonsillitis, SF, impetigo, and obstructive sleep apnea syndrome, were associated with the occurrence of ARF and RHD. ARF and RHD were still prevalent in young people of developing countries and economically poor populations of high-income countries. Universal disease registration systems were critical to locating disease outbreaks, tracking disease transmission, and identifying high-risk populations. Four-level prevention strategies were effective in reducing the incidence and mortality of ARF and RHD.ConclusionsRegistry and preventive measures for ARF and RHD should be strengthened in areas of dense population; poor sanitation; resurgence of SF; and high incidence of streptococcal pharyngitis, impetigo, and obstructive sleep apnea syndrome.

Abstract Background With the COVID-19 outbreak in China, the Chinese government took measures to prevent and control the spread of the virus. In-person teaching was replaced by distance learning, which was an unknown challenge for students. In this context, little is known about the perceived distress of nursing students and the relationship between psychological capital, perceived distress, and psychological stress. This study examined the relationship between psychological capital, psychological distress, and perceived stress, and the mediating role of psychological capital in the relationship between perceived stress and psychological distress among nursing students. Methods This cross-sectional survey was conducted between January and December 2020 using a convenience sampling method involving 359 undergraduate and specialist nursing students at a tertiary hospital in Shandong Province. Standardised instruments were used to measure psychological capital, psychological stress, and perceived stress. We used SPSS 24.0 and PROCESS macro to analyse the data. Results There was a statistically significant difference in perceived stress among students based on whether they liked the nursing profession (P

Abstract Background Nursing handovers are a critical component of patient safety. Researchers have performed many primary studies in this field, mainly reporting findings from changes in nursing handover patterns. However, few quantitative studies have explored the factors that influence handover quality. Therefore, this study aimed to investigate the quality of handovers and explore the associations between handover quality, job satisfaction, and group cohesion among psychiatric nurses. Methods This cross-sectional study included 186 registered psychiatric nurses from a Chinese hospital, who responded to the Handover Evaluation Scale, McCloskey/Mueller Satisfaction Scale, and Group Cohesion Scale. Bootstrap analyses were used to evaluate the mediating effect between variables. Results The average item score for handover quality was (5.85 ± 1.14), and job satisfaction and group cohesion could predict the variance of handover quality. Job satisfaction could partially mediate between group cohesion and handover quality, and the value of the mediating effect was 45.77%. Conclusion The quality of psychiatric nursing handovers has enhanced space. Thus, hospital managers should take various measures to strengthen group cohesion and promote job satisfaction, both of which help improve the quality of psychiatric nursing handovers.

Accurate grasping state detection is critical to the dexterous operation of robots. Robots must use multiple modalities to perceive external information, similar to humans. The direct fusion method of visual and tactile sensing may not provide effective visual–tactile features for the grasping state detection network of the target. To address this issue, we present a novel visual–tactile fusion model (i.e., RFCT) and provide an incremental dimensional tensor product method for detecting grasping states of weak-stiffness targets. We investigate whether convolutional block attention mechanisms (CBAM) can enhance feature representations by selectively attending to salient visual and tactile cues while suppressing less important information and eliminating redundant information for the initial fusion. We conducted 2250 grasping experiments using 15 weak-stiffness targets. We used 12 targets for training and three for testing. When evaluated on untrained targets, our RFCT model achieved a precision of 82.89%, a recall rate of 82.07%, and an F1 score of 81.65%. We compared RFCT model performance with various combinations of Resnet50 + LSTM and C3D models commonly used in grasping state detection. The experimental results show that our RFCT model significantly outperforms these models. Our proposed method provides accurate grasping state detection and has the potential to provide robust support for robot grasping operations in real-world applications.

BackgroundPsychiatric nurses need to keep close contact with patients suffering from mental illness. Because of the special nature of their profession, there is an increasing incidence of job burnout among psychiatric nurses.AimThis study examined the relationship between psychiatric nurses’ perceived organizational support, job burnout, and psychological capital. It also investigated the mediating role of psychological capital in the relationship between their perceived organizational support and job burnout.MethodsA total of 916 psychiatric nurses were recruited from 6 grade-III mental facilities in Shandong Province using the stratified sampling approach. Their data were collected and examined using a general demographic data questionnaire, The Maslach Burnout Inventory, the Perceived Organizational Support Scale, and the Psychological Capital Questionnaire.ResultsThe total score of job burnout was 53.71 ± 16.37. Specifically, 73.69% of the nurses had moderate to severe emotional exhaustion, 76.75% had moderate to severe job burnout pertaining to depersonalization, and 98.80% had moderate to severe job burnout pertaining to personal accomplishment. Spearman’s correlation analysis showed that both psychological capital (r = −0.35, p

Vacuolar ATPases (V-ATPases) are proton pumps for proton translocation across membranes that utilize energy derived from ATP hydrolysis; OsV-ATPase subunit d (OsV-ATPase d) is part of an integral, membrane-embedded V0 complex in the V-ATPase complex. Whether OsV-ATPase d is involved in phytohormone biosynthesis and resistance in rice remains unknown. The knockout mutants of OsV-ATPase d in rice were generated using the CRISPR/Cas9 system, and mutation of OsV-ATPase d did not show any detrimental effect on plant growth or yield productivity. Transcriptomic results showed that OsV-ATPase d is probably involved in mediating the biosynthesis of plant hormones and resistance in rice. Compared to wild type, mutation of OsV-ATPase d significantly increased JA and ABA biosynthesis and resistance against Southern rice black-streaked dwarf virus (SRBSDV), but it decreased resistance against Rice stripe virus (RSV) in rice. The data presented in this study reveal that OsV-ATPase d mediates phytohormone biosynthesis and virus resistance in rice and can be selected as a potential target for resistance breeding in rice.

To investigate the clinical characteristics and treatment of septic arthritis caused by Streptococcus pyogenes(S. pyogenes) in children, we retrospectively analyzed the clinical data, laboratory results, treatments and outcomes of three pediatric cases of septic arthritis caused by S. pyogenes occurring from 2016–2018. The three cases of septic arthritis included 1 boy and 2 girls, aged from 2–7 years. Two patients experienced fever, and in all three cases, the affected joints showed redness, swelling, an increased local skin temperature, tenderness and restricted limb movement. At the first visit, all three cases showed a significantly increased white blood cell count [(27.68–32.02)×109/mL] and a significantly increased erythrocyte sedimentation rate (113–134 mm/h). The C-reactive protein level was significantly increased in two cases (67 mg/L, 147.7 mg/L) and normal in one case. The procalcitonin level was normal in 1 case, elevated in 1 case, and undetected in 1 case. S. pyogenes isolated from cases 1 and 2 were emm1/ST28 and from case 3 was emm12/ST36. All patients were treated by abscess incision and drainage, and S. pyogenes was cultured in the abscess puncture fluid. All patients were treated with intravenous antibiotics after admission, and all patients were cured and discharged. The patients were followed up for 2 months, and their condition was improved and stable. No sequelae such as heart and kidney damage were detected. In conclusion, for children with septic arthritis, early diagnosis and timely treatment with incision and drainage followed by culture of the abscess puncture fluid are important. Once S. pyogenes infection is confirmed, β-lactam antibiotics provide effective treatment, avoiding use of broad-spectrum antibiotics.

Internet of Things (IoT) devices facilitate intelligent service delivery in a broad range of settings, such as smart offices, homes and cities. However, the existing IoT access control solutions are mainly based on conventional identity management schemes and use centralized architectures. There are known security and privacy limitations with such schemes and architectures, such as the single-point failure or surveillance (e.g., device tracking). Hence, in this paper, we present an architecture for capability-based IoT access control utilizing the blockchain and decentralized identifiers to manage the identity and access control for IoT devices. Then, we propose a protocol to provide a systematic view of system interactions, to improve security. We also implement a proof-of-concept prototype of the proposed approach and evaluate the prototype using a real-world use case. Our evaluation results show that the proposed solution is feasible, secure, and scalable.

The oil source of the Lower Paleozoic petroliferous system in the Tarim Basin is still controversial. Based on the detailed analysis of the molecular isotopic geochemistry of the crude oil from well Yubei 1 in the Yubei area of the Tarim Basin, the oil source of the Lower Paleozoic petroliferous system in this area was studied by inversion ideas. The crude oil from well Yubei 1 was the superimposed product of two phases of accumulation, and the oil sources of the two phases were the products of the same set of Cambrian source rocks during the peak period of oil generation. The burial depth of Cambrian source strata in different areas could be the main factor leading to multiple phases of hydrocarbon charging. Crude oil accumulated in the early stage experienced severe biodegradation due to strata uplift and erosion, while oil in the late stage was well preserved. Although the biomarker assemblages and molecular isotopic compositions in the Yubei 1 oil can be generally correlated with oils from the Lower Paleozoic petroleum system in the central Tarim Basin, the distributions of aryl isoprenoids suggested that the depositional environment of the Cambrian source rock in the southern Tarim Basin could be different from that in the central Tarim Basin, which worth a further in-depth study.

PurposeEnhanced external counterpulsation (EECP) is a new non-drug treatment for coronary artery disease (CAD). However, the long-term effect of EECP on endothelial dysfunction and exercise tolerance, and the relationship between the changes in the endothelial dysfunction and exercise tolerance in the patients with coronary heart disease are still unclear.MethodsA total of 240 patients with CAD were randomly divided into EECP group (n = 120) and control group (n = 120). All patients received routine treatment of CAD as the basic therapy. Patients in the EECP group received 35 1-h daily sessions of EECP during 7 consecutive weeks while the control group received the same treatment course, but the cuff inflation pressure was 0–10 mmHg. Peak systolic velocity (PSV), end diastolic velocity (EDV), resistance index (RI), and inner diameter (ID) of the right carotid artery were examined using a Color Doppler Ultrasound and used to calculate the fluid shear stress (FSS). Serum levels of human vascular endothelial cell growth factor (VEGF), vascular endothelial cell growth factor receptor 2 (VEGFR2), and human angiotensin 2 (Ang2) were determined by enzyme-linked immunosorbent assay (ELISA). Exercise load time, maximal oxygen uptake (VO2max), metabolic equivalent (METs), anaerobic threshold (AT), peak oxygen pulse (VO2max/HR) were assessed using cardiopulmonary exercise tests.ResultsAfter 1 year follow-up, the EDV, PSV, ID, and FSS were significantly increased in the EECP group (P < 0.05 and 0.01, respectively), whereas there were no significant changes in these parameters in the control group. The serum levels of VEGF and VEGFR2 were elevated in the EECP and control groups (all P < 0.05). However, the changes in VEGF and VEGFR2 were significantly higher in the EECP group than in the control group (P < 0.01). The serum level of Ang2 was decreased in the EECP group (P < 0.05) and no obvious changes in the control group. As for exercise tolerance of patients, there were significant increases in the exercise load time, VO2max, VO2max/HR, AT and METs in the EECP group (all P < 0.05) and VO2max and METs in the control group (all P < 0.05). Correlation analyses showed a significant and positive correlations of VEGF and VEGFR2 levels with the changes in FSS (all P < 0.001). The correlations were still remained even after adjustment for confounders (all Padjustment < 0.001). Linear regression displays the age, the medication of ACEI (angiotensin-converting enzyme inhibitors) or ARB (angiotensin receptor blockers), the diabetes and the changes in VEGF and VEGFR2 were positively and independently associated with the changes in METs after adjustment for confounders (all Padjustment < 0.05).ConclusionThe data of our study suggested that EECP is a useful therapeutic measurement for amelioration of endothelial dysfunction and long-term elevation of exercise tolerance for patients with coronary heart disease.Clinical trial registration[http://www.chictr.org.cn/], identifier [ChiCTR1800020102].

Summary: From flexible electronics and multifunctional textiles to artificial tissues, polymers penetrate nearly every aspect of modern technology. High thermal conductivity of polymers is often required in their applications, where heat dissipation is crucial to maintain product reliability and functionality. However, the intrinsic thermal conductivity of bulk polymers is largely hindered by the randomly coiled and entangled chain conformation. Here, we report a copolymerization strategy that can simultaneously manipulate the intrachain and interchain hopping and increase the thermal conductivity of linear copolymerized polyimide (PI) to three times higher than that of pure PI at a low-level introduction of 2,4,5,7-tetraamino-1,8-dihydroxyanthracene-9,10-dione (10%). In addition, the large-scale copolymerized PI films display thermal stability after annealing. These remarkable results allow bulk PI to be a potential candidate for thermal management, and this copolymerization method may benefit future synthesis of interfacial thermal materials.

Heteroaromatic polyimides (PIs) containing benzimidazole have attracted tremendous attention due to their positive impact on the properties of PIs. Some research on PIs containing 4,4′-[5,5′-bi-1H-benzimidazole]-2,2′-diylbis-benzenamine (4-AB) has been reported. However, reports are lacking on homo-polyimides (homo-PIs) containing 3,3′-[5,5′-bi-1H-benzimidazole]-2,2′-diylbis-benzenamine (3-AB), which is one of the isomers of 4-AB. In this paper, the influence of amino groups’ positions on the performance of homo-PIs was investigated. It was found that the net charge of the amine N group in 4-AB was lower than that of 3-AB, resulting in higher reactivity of 4-AB. Consequently, PIs containing 4-AB displayed better mechanical performance. Molecular simulation confirmed that 3-AB and its corresponding PI chain exhibited distorted conformation, leading to the PI films containing 3-AB having a lighter color. In addition, the 3-AB structure was calculated to have higher rotational energy compared to 4-AB, resulting in a higher glass transition temperature (Tg) in PIs prepared from 3-AB. On the other hand, PIs containing 4-AB exhibited a higher level of molecular linearity, leading to a lower coefficient of thermal expansion (CTE) compared to PIs prepared from 3-AB. Furthermore, all PIs showed higher thermal stability with a 5% weight loss temperature above 530 °C and Tg higher than 400 °C.

Exploration experiences have showed that the main source rocks of the Lower Cambrian have not been developed in the Bachu uplift; however, the well MB1 in this area had a good oil and gas showing in the Lower Cambrian.To clarify the hydrocarbon source of well MB1 and evaluate the exploration potential of the Bachu uplift, the core extracts from the oil and gas display section of the Lower Cambrian Wusongge'er Formation of well MB1 were studied here by using of geochemical analysis, moreover, oil-oil and oil-source correlations have also been carried out.The saturated hydrocarbon fraction of extracts showed a typical signature which is consistent with marine crude oil in the Tarim Basin, of which the n-alkanes have a single-peak pre-peak distribution, the series is preserved intact and there was no apparent "hump" in the basline, the ratio of Pr/Ph was 0.89, the abundance of the tricyclic terpanes was higher than that of the hopanes, the C27-C28-C29ααα20R regular steranes had a typical "V" shape, the carbon isotope value of crude oil is -30.8‰, and the trifluorene compounds were obviously override thiofluorene.It then indicates that they were derived from the saprolite-type sources with a strongly reducing sedimentary environment, moreover, the organic matters are high mature.The Lower Cambrian oil showed in well MB1 have the same origin as the Ordovician crude oil in the Yubei 1 belt, and both of them probably came from the Lower Cambrian source rocks. It was inferred that the Lower Cambrian oil and gas in well MB1 came from the peripheral Lower Cambrian source rocks or paleo-oil reservoirs, which enhanced the exploration potential of Cambrian in the Bachu uplift.

BackgroundPsychiatric nurses often face abuse, attacks, escape, suicides, and other situations related to the care of patients with mental disorders, which are more likely to induce psychological distress.AimsThis study aimed to examine the relationship between coping styles and psychological distress among Chinese psychiatric nurses in Shandong and the significance of sleep quality as a mediating factor.MethodsA total of 812 psychiatric nurses in Shandong, China, were investigated using the Psychological Distress Scale (K10), Simplified Coping Style Questionnaire (SCSQ), Pittsburgh Sleep Quality Index (PSQI) and self-compiled general information questionnaire.ResultsPsychological distress was detected in 571 psychiatric nurses (70.3%). The psychological distress of psychiatric nurses was significantly different with respect to professional title (χ2 = 10.627, P < 0.05) and shift work (χ2 = 9.120, P < 0.01). Psychological distress positively correlated with negative coping style (r = 0.266, P < 0.01) and sleep quality (PSQIT) (r = 0.532, P < 0.01). A significant positive correlation was found between psychological distress and all dimensions of sleep quality (r = 0.158–0.456, P < 0.05). Professional title, positive coping style, negative coping style, sleep quality (PSQIT), subjective sleep quality, sleep disorder and daytime dysfunction predicted psychological distress in psychiatric nurses (R2 = 0.363, F = 65.343, P < 0.01). The relationship between negative coping style and psychological distress was partially mediated by sleep quality, with the mediating effect accounting for 37.97% of the total effect.ConclusionsPsychiatric nurses have a high rate of psychological distress, which is closely related to coping styles, and sleep quality has a certain regulatory effect.

BackgroundNurses are facing increasing pressure due to the progressing of society, broadening of nursing service connotation, and increasing of the masses’ demand for medical treatment. Psychiatric nurses face suicides, violence, and lost along with other accidents involving patients with mental disorders under higher psychological pressure. A coping style, which is affected by individual emotions and cognition, is an essential psychological resource that allows individuals to regulate stress. The purpose of this study was to investigate the correlation between self-acceptance and the positive coping style of psychiatric nurses, and investigate the mediating role of emotional intelligence.MethodsA total of 813 psychiatric nurses from six natural regions in Shandong Province were investigated using the Self-Acceptance Questionnaire (SAQ), Emotional Intelligence Scale (EIS), Simplified Coping Style Questionnaire (SCSQ), and self-compiled general information questionnaire.ResultsThe total EIS score of psychiatric nurses was 3.848 ± 0.459. The highest score was for others’ emotional management (4.071 ± 0.548) and the lowest was for emotion perception (3.684 ± 0.483). EIS and positive coping style were statistically significant based on age, work experience, professional title, education level, and gender (p

In order to avoid decomposition of solid lubricants during laser processing and improve the lubrication stability of laser-clad self-lubricating coating, a novel multilayer structural WS2/NbC/Stellite 6 metal matrix self-lubricating coating (MMSC) with laser texturing layer (LTL), lubricant layer (LL) and laser-clad sealing layer (LSL) was fabricated on Cr12MoV steel via laser surface texturing (LST) and laser surface cladding (LSC) two-step process. The microstructure, phase and tribological properties of the multilayer structural MMCC were investigated by means of optical microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman spectroscopy, as well as dry sliding wear test in wide-temperature (room temperature, 200 °C, 400 °C, and 800 °C). Results show that the multilayer structure partially inhibited the decomposition of the lubricant so that WS2 particles retained in the coating and NbC promoted the formation of a new lubricating phase CrS in decomposed WS2. The multilayer structural coating prepared in two steps had lower friction coefficient (0.226) and wears volume (31.916 mm3) at room temperature (RT). Moreover, the friction coefficient of the multilayer WS2/NbC/Co-based self-lubricating coating was still low (0.306) at 800 °C, only. Adhesive wear was identified as the main wear mechanism and the discrepancies of tribological properties were found to be mainly dependent of the kind of lubricating films generated at the wear surface.

Abstract In this paper, some theoretical results of PID control of second order nonlinear uncertain stochastic system are given via inequalities. We extend the results of the corresponding deterministic systems to stochastic systems. Specifically, as long as we have a certain understanding of the upper bound of the derivative of the unknown nonlinear drift term and diffusion term, an analytic design method can be constructed for these three PID parameters to ensure the global stability and asymptotic stability of the closed-loop control systems. In addition, the numerical simulation results verify the theoretical analysis results.

The Cretaceous oil-bearing strata in the Tarim Basin have a good exploration potential. The Shunbei area has good oil and gas shows in the Cretaceous, and a small amount of crude oil has been obtained by testing. The geochemical characteristics of the Cretaceous crude oil as well as the oil-oil and oil-source correlations were studied systematically in order to determine the genesis types and sources of crude oil in the Shunbei area. The saturated hydrocarbon chromatogram of the Cretaceous crude oil in the Shunbei area shows a unimodal distribution. The n-alkanes are intact and the distribution is unchanged without any obvious "UCM". The Pr/Ph values of crude oil range 1.65-1.71. The C21TT/C23TT ratio is >1. In biomarkers, the hopane series are dominant and the ∑tricyclic terpanes/∑hopanes ratio is < 1. The gammacerane and triaryl stanine compounds are abundant, indicating that the crude oil of continental origin is well preserved. The Cretaceous crude oil in the Shunbei area and the Yingmai, Dawanqi and Dalaoba areas around the Kuqa Sag in the north, and the Triassic Huangshanjie mudstones in the Kuqa River area show similar m/z 191 biomarker patterns, which indicates that the crude oil was sourced from the Huangshanjie mudstones in the Kuqa Sag. The thermal evolution degrees of crude oil decrease from Dawanqi, Yingmai to Shunbei. We inferred that the early terrestrial hydrocarbon was sourced in the Triassic source rocks in the Kuqa Sag, and then migrated laterally from north to south through the Cretaceous sand bodies, the T40 unconformity surface and the faults.

In recent years, great achievements have been made in the exploration of ultra-deep marine oil and gas in the Tarim Basin. New oil and gas discoveries have been achieved in the Shunbei Ordovician, Tazhong Cambrian and Tahe deep strata, which provide abundant basic data for studying the marine oil and gas accumulation in the Tarim Basin. The marine oil and gas in the Tarim Basin are mainly distributed in the platform-basin area. There are various types of reservoirs, and the physical properties of crude oil vary greatly, showing the complexity of hydrocarbon accumulation. Through the analysis of a large number of samples, simulation experiments and extensive geology and geochemistry analysis, combined with the research results of tectonic evolution, sequence stratigraphy, sedimentary facies and sedimentary environments, some significant progress has been achieved such as the distribution and evolution of source rocks, oil and gas geochemistry characteristics, and the distribution characteristics of marine oil and gas reservoirs. The following achievements have been made: 1) clarification that the marine oil and gas in the Tarim platform-basin area mainly come from the Lower Cambrian-Middle/Lower Ordovician source rocks formed under strongly reducing environments, especially the Lower Cambrian Yuertusi Formation in the platform-basin. Two alterations types of ultra-deep marine reservoirs, namely, TSR and thermal cracking are defined, and the corresponding identification indicators are proposed. 2) by establishing the sedimentary development mode of the gentle slope-type high-quality Yuertusi source rocks, through well-seismic calibration, forward modeling, regional survey line interpretation of seismic facies, 3D area attribute analysis and seismic inversion, the distribution of source rocks in the Yuertusi Formation may be predicted, and their evolution characteristics clarified: the "high-pressure hydrocarbon generation evolution inhibition mode" under the long-term low geothermal background since the Yanshan period has delayed the thermal evolution of Shuntuoguole low uplift Cambrian source rocks, and the Shuntuoguole area still has the formation conditions of late high-maturity liquid hydrocarbon. 3) by comparing the hydrocarbon accumulation characteristics of the platform-basin area, the Ordovician oil and gas distribution characteristics have been clarified, further delineating the Cambrian Yuertusi in situ source rocks there, and identification of the light oil-gas reservoirs matching with the active strike-slip faults in the late Yanshan period and charged by the late hydrocarbon supply, which provide an key direction for oil and gas exploration in the ultra-deep carbonate rocks of the Tarim platform-basin area.

A lot of adaptive signal decomposition methods have been applied for nonstationary DPMIG electrical signals as they are always affected by noise. Recently, to solve the problems of former methods caused by the Gibbs phenomenon and the calculation of extremas when dealing with broadband electrical signals such as square signals and sawtooth signals with “sharp corners”, broadband mode decomposition (BMD) method was proposed and the application of the algorithm showed a good performance. The main idea of BMD is searching in the associative dictionary contains both broadband and narrowband signals using a regulated differential operator as the optimal object. However, when applied to a broadband signal interfered by strong noise, as the relative bandwidth is not small enough, the BMD algorithm may treat the broadband signal to be several narrowband components. Therefore, modulated broadband mode decomposition (MBMD) is proposed in this paper to denoise broadband electrical signals based on modulated differential operator. By multiplying a high frequency mono-frequency signal, the relative bandwidth of the effective broadband signal is translated to be far less than 1, and the broadband signals are treated as approximate broadband signals to get more accurate decomposition results. For the further feature extraction of the electrical signals, locality preserving projection (LPP) is applied combined with MBMD. The effectiveness of the proposed method is testified by simulation and experimental signals, results show that it is effective when drawing broadband feature from noise, as well as is adaptive for the feature extraction of double pulse metal inert gas welding.

Streptococcus pyogenes is a bacterial pathogen that causes a wide spectrum of clinical diseases exclusively in humans. The distribution of emm type, antibiotic resistance and virulence gene expression for S. pyogenes varies temporally and geographically, resulting in distinct disease spectra. In this study, we analyzed antibiotic resistance and resistance gene expression patterns among S. pyogenes isolates from pediatric patients in China and investigated the relationship between virulence gene expression, emm type, and disease categories. Forty-two representative emm1.0 and emm12.0 strains (n = 20 and n = 22, respectively) isolated from patients with scarlet fever or obstructive sleep apnea-hypopnea syndrome were subjected to whole-genome sequencing and phylogenetic analysis. These strains were further analyzed for susceptibility to vancomycin. We found a high rate and degree of resistance to macrolides and tetracycline in these strains, which mainly expressed ermB and tetM. The disease category correlated with emm type but not superantigens. The distribution of vanuG and virulence genes were associated with emm type. Previously reported important prophages, such as φHKU16.vir, φHKU488.vir, Φ5005.1, Φ5005.2, and Φ5005.3 encoding streptococcal toxin, and integrative conjugative elements (ICEs) such as ICE-emm12 and ICE-HKU397 encoding macrolide and tetracycline resistance were found present amongst emm1 or emm12 clones from Shenzhen, China.

Humans maintain good memory and recognition capability of previous environments when they are learning about new ones. Thus humans are able to continually learn and increase their experience. It is also obvious importance for autonomous mobile robot. The simultaneous localization and mapping system plays an important role in localization and navigation of robot. The loop-closure detection method is an indispensable part of the relocation and map construction, which is critical to correct mappoint errors of simultaneous localization and mapping. Existing visual loop-closure detection methods based on deep learning are not capable of continual learning in terms of cross-scene environment, which bring a great limitation to the application scope. In this article, we propose a novel end-to-end loop-closure detection method based on continual learning, which can effectively suppress the decline of the memory capability of simultaneous localization and mapping system by introducing firstly the orthogonal projection operator into the loop-closure detection to overcome the catastrophic forgetting problem of mobile robot in large-scale and multi-scene environments. Based on the three scenes from public data sets, the experimental results show that the proposed method has a strong capability of continual learning in the cross-scene environment where existing state-of-the-art methods fail.

Due to the little variation in defect points, tile block defect detection typically detects subtle defects in large-format images, allowing defective characteristics to be displayed regionally. Traditional convolutional neural network architectures that extract regional features take into account the connection between regional features simply, resulting in the presence of region-specific bias, which makes tile block defect detection still a challenging task. To address this challenge, this paper divides feature information into patches that can represent different regional features. Additionally, the relationship between different patches and tile block defects is studied; as a result, this paper proposes a new attention mechanism called the Cross Patch Attention Module (CPAM). Since the regional performance of patches is consistent with the tile block defect characteristics, CPAM can distinguish various regional features by patches. Then, in order to create reliable one-dimensional patch information, CPAM provides a method to connect patches linearly in two spatial directions. This takes into account the correlation of adjacent patches in various spatial directions. Finally, by extracting the regional characteristics of patches, CPAM can successfully assist the model in distinguishing the importance of different patches. The experimental results demonstrate that CPAM has excellent performance for tile block defect detection, and plugging CPAM into different end-to-end models can have a good gain effect, which can effectively and stably help the model to complete the task of tile block defect detection.

To improve the adaptive clamping performance of traditional single-tendon-driven underactuated grippers for grasping multiple categories of objects, a novel dual-tendon-driven underactuated gripper is proposed in this paper. First, two independent tendons with different winding paths are designed in the gripper to realize the changeable resultant moment of the end knuckle rotating joint and the movement sequences of gripper knuckles driven by different tendons are analysed too. Then, some kinematic analysis and dynamical simulations are carried out to verify the validation of the knuckle structure and dual-tendon winding path design. At last, a prototype of the novel gripper is manufactured and some grasping experiments are carried out on multiple categories of objects, with different sizes and shapes. The experimental results show that all the objects can be clamped tightly. Compared with the traditional single-tendon-driven gripper, the novel one can achieve a more flexible grasping operation and a larger end clamping force, which are more suitable for the adaptive grasping requirements of robotic automatic sorting.

The Internet of Things (IoT) aims at connecting things to the Internet in a peer-to-peer paradigm for data collecting and data sharing in our daily life. A blockchain is an immutable append-only ledger maintained by a peer-to-peer network, where the whole network needs to reach a consensus on the transactional data stored on the ledger. With the decentralization nature, the design of IoT and blockchain aligns with each other well. Blockchain has been integrated with the IoT to solve the existing IoT problems. Our research focuses on analyzing the solutions proposed in academia and the methodologies used to integrate blockchain with the IoT. Through conducting a systematic literature review (SLR) on peer-reviewed, published articles on blockchain-based solutions for IoT, we gather the knowledge on current technical approaches implemented to integrate blockchain into the IoT. Majority of the research in this space is either at a conceptual level or at a very early stage. However, we only found 35 published papers with the real implementation of blockchain in the IoT platforms. We elicit the challenges of the IoT that were being addressed, and the detailed design of the blockchain-based solutions from two perspectives, namely data management and thing management. The evaluation methods and metrics used by those works are also being recorded and analyzed. In addition to the analysis of the literature, we provide our insights on improving the existing solutions and research methodology based on our expertise and experience on the blockchain.

When performing robotic automatic sorting and assembly operations of multi-category hardware, there are some problems with the existing convolutional neural network visual recognition algorithms, such as large computing power consumption, low recognition efficiency, and a high rate of missed detection and false detection. A novel efficient convolutional neural algorithm for multi-category aliasing hardware recognition is proposed in this paper. On the basis of SSD, the novel algorithm uses Resnet-50 instead of VGG16 as the backbone feature extraction network, and it integrates ECA-Net and Improved Spatial Attention Block (ISAB): two attention mechanisms to improve the ability of learning and extract target features. Then, we pass the weighted features to extra feature layers to build an improved SSD algorithm. At last, in order to compare the performance difference between the novel algorithm and the existing algorithms, three kinds of hardware with different sizes are chosen to constitute an aliasing scene that can simulate an industrial site, and some comparative experiments have been completed finally. The experimental results show that the novel algorithm has an mAP of 98.20% and FPS of 78, which are better than Faster R-CNN, YOLOv4, YOLOXs, EfficientDet-D1, and original SSD in terms of comprehensive performance. The novel algorithm proposed in this paper can improve the efficiency of robotic sorting and assembly of multi-category hardware.

This paper presents an approach on stability analysis of cable-driven parallel robots (CDPRs) considering cable mass based on cable tensions and stiffness matrix condition numbers. A cable model is introduced considering the effect of cable mass. A stiffness model is established based on the cable model. Then, the stiffness matrix condition numbers are presented. Furthermore, the stability of CDPRs is discussed. Numerical simulations show that the stability is better in the center and at the top of the whole workspace than in other places, which agrees well with theoretical predictions. The mixed evaluation stability indices considering cable mass and neglecting cable mass are, respectively, compared. The results show that cable mass is not negligible when evaluating accurately the stability of a cable-driven parallel robot.

Access control is a critical aspect for improving the privacy and security of IoT systems. A consortium is a public or private association or a group of two or more institutes, businesses, and companies that collaborate to achieve common goals or form a resource pool to enable the sharing economy aspect. However, most access control methods are based on centralized solutions, which may lead to problems like data leakage and single-point failure. Blockchain technology has its intrinsic feature of distribution, which can be used to tackle the centralized problem of traditional access control schemes. Nevertheless, blockchain itself comes with certain limitations like the lack of scalability and poor performance. To bridge the gap of these problems, here we present a decentralized capability-based access control architecture designed for IoT consortium networks named IoT-CCAC. A blockchain-based database is utilized in our solution for better performance since it exhibits favorable features of both blockchain and conventional databases. The performance of IoT-CCAC is evaluated to demonstrate the superiority of our proposed architecture. IoT-CCAC is a secure, salable, effective solution that meets the enterprise and business’s needs and adaptable for different IoT interoperability scenarios.

BackgroundAt present, the relationship between thyrotropin (TSH) and free thyroxine (FT4) in relation to postmenstrual age (PMA) in preterm infants is still unclear, and there is no reliable standard thyroid hormone reference ranges, resulting in different diagnostic criteria for congenital hypothyroidism been used by different newborn screening programs and different countries.ObjectivesTo investigate the relationship between TSH/FT4 and PMA in very preterm infants (VPIs) born with gestational age (GA)

In aluminum alloy double pulse metal inert-gas (DPMIG) welding, the outputting arc current waveform is distorted under the influence of various factors such as harmonics and impact loads. The arc distortion of aluminum alloy DPMIG welding affects the arc stability and welding quality. Based on the collected welding current signal, a feature extraction method is proposed for quality detection of the aluminum alloy DPMIG welding. The wavelet method is adopted to eliminate the noise of the welding current signal. The local mean decomposition (LMD) is performed to the welding current signal to obtain a series of Product Function (PF) components with real physical meaning. The Hilbert transformation is subsequently performed to the PF components to obtain the time frequency distribution of welding arc signal energy. The approximate entropy (ApEn) of the time frequency distribution of the welding current signal is calculated to evaluate the arc stability and the welding formation quality. Application of the proposed feature extraction method indicates that the combination of the wavelet and LMD can effectively extract the distortion components of the welding current signal. The time frequency distribution of the PF components of the welding current can clearly reflect the concentration and dispersion of the arc energy. The approximate entropy of the time frequency distribution of the welding current can be quantitively reflect the arc stability and the welding formation quality in the aluminum alloy double pulse MIG welding.

Cardiovascular magnetic resonance (CMR) imaging has become an accurate and versatile imaging modality to visualize the cardiovascular system in normal or abnormal conditions. In preclinical research, small rodent animal models of human cardiovascular diseases are frequently used to investigate the basic underlying mechanism of normal and abnormal cardiac function and for monitoring the disease progression under therapy. Technical improvements have enabled the transfer of CMR to small animal research, and as such made this non-invasive technique available to provide insights into cardiac morphology, function, perfusion, and pathophysiology in small animal cardiac disease models. This article reviews the basic technical approaches to in vivo small animal magnetic resonance imaging and its variants for the most promising applications.

Adaptive sparsest narrow-band decomposition is the most sparse solution to search for signals in the over-complete dictionary library containing intrinsic mode functions, which transform the signal decomposition into an optimization problem, but the calculation accuracy must be improved in the case of strong noise interference. Therefore, in combination with the algorithm of the complementary ensemble empirical mode decomposition, a new method of the complementary ensemble adaptive sparsest narrow-band decomposition is obtained. In the complementary ensemble adaptive sparsest narrow-band decomposition, the white noise opposite to the paired symbol is added to the target signal to reduce the reconstruction error and realize the adaptive decomposition of the signal in the process of optimizing the filter parameters. The analysis results of the simulation and experimental data show this method is superior to complementary ensemble empirical mode decomposition and adaptive sparsest narrow-band decomposition in inhibiting the mode confusion, endpoint effect, improving the component orthogonality and accuracy, and effectively identifying the gears fault types.

Reperfusion strategies in acute myocardial infarction (AMI) can cause a series of additional clinical damage, defined as myocardial ischemia/reperfusion (I/R) injury, and thus there is a need for effective therapeutic methods to attenuate I/R injury. miR-26a-5p has been proven to be an essential regulator for biological processes in different cell types. Nevertheless, the role of miR-26a-5p in myocardial I/R injury has not yet been reported. We established an I/R injury model in vitro and in vivo. In vitro, we used cardiomyocytes to simulate I/R injury using hypoxia/reoxygenation (H/R) assay. In vivo, we used C57BL/6 mice to construct I/R injury model. The infarct area was examined by TTC staining. The level of miR-26a-5p and PTEN was determined by bioinformatics methods, qRT-PCR, and western blot. In addition, the viability and apoptosis of cardiomyocytes were separately detected by MTT and flow cytometry. The targeting relationship between miR-26a-5p and PTEN was analyzed by the TargetScan website and luciferase reporter assay. I/R and H/R treatment induced myocardial tissue injury and cardiomyocyte apoptosis, respectively. The results showed that miR-26a-5p was down-regulated in myocardial I/R injury. PTEN was found to be a direct target of miR-26a-5p. Furthermore, miR-26a-5p effectively improved viability and inhibited apoptosis in cardiomyocytes upon I/R injury by inhibiting PTEN expression to activate the PI3K/AKT signaling pathway. miR-26a-5p could protect cardiomyocytes against I/R injury by regulating the PTEN/PI3K/AKT pathway, which offers a potential approach for myocardial I/R injury treatment.

Myocardial infarction (MI) is the leading cause of morbidity and mortality worldwide. Nanoparticle systems carrying drugs have already been developed to treat MI. To improve the efficiency of tanshinone (TAN), and to achieve the synergistic effect of TAN and puerarin (PUE), PUE-prodrug and TAN co-loaded solid lipid nanoparticles (SLN) was structured and utilized for MI treatment in the present research. PUE-prodrug was synthesized by an esterification reaction. PUE-prodrug and TAN co-loaded SLN (PUEp/TAN-SLN) were prepared by a single emulsification followed by a solvent evaporation method. The physicochemical properties of SLN were characterized and the in vivo infarct therapy effects were evaluated in MI rats. PUE-prodrug and TAN contained SLN showed a size of 112.6 ± 3.1 nm. The SLN encapsulation reduced the cytotoxicity of drugs and was a safer system. PUEp-SLN exhibited a 1.7-fold increase in comparison to PUE-SLN (21.2 ± 2.1 versus 12.5 ± 1.5 mg/L), in the mean time a 3.4-fold increase compared with free PUE in heart drug concentration (21.2 ± 2.1 versus 6.3 ± 0.9 mg/L). In vivo infarct therapy efficiency of double drugs loaded PUEp/TAN-SLN (17 ± 1.9%) was significantly better than the single drug loaded PUEp-SLN (31 ± 1.6%) and TAN-SLN (40 ± 2.2%). PUE-prodrug contained, double drugs co-loaded SLN can be utilized as promising candidate delivery system for cardioprotective drugs in treatment of myocardial infarction.