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This paper addresses the trajectory planning and control problem of multi-spacecraft formation reconstruction in the presence of obstacles. By expressing spacecraft dynamics relative to a leader spacecraft in the formation, an integrated planning and control approach named predictive null-space-based behavior control (PNSBC) is proposed. First, a planner using null-space-based behavior control (NSBC) is designed at an upper layer to resolve multi-task conflicts. Here, both global tasks, e.g. formation keeping, and local tasks, e.g. obstacle avoidance, are considered. Second, a tracking controller is designed at the bottom layer using decentralized model predictive control. Unlike traditional two-layer approaches that treat planning and control separately, the proposed PNSBC integrates the planning and control in two ways: 1) the planner provides reference trajectories for the controller to track; 2) the model predictive control (MPC) controller provides predicted trajectories that can be employed by the planner for future task priority predictions, which extends the capability of NSBC from one-step planning to multi-step predicting. In addition, the computational burden of the MPC controller is greatly reduced by putting the nonlinear obstacle avoidance constraints into the planner as a local task. Simulation results show that such integrated approach has better performance in terms of safety constraint guarantee, fuel consumption and travel distance when compared against traditional non-integrated approaches, or all-in-one MPC methods, while constraints and task objectives are fully satisfied. [ABSTRACT FROM AUTHOR]

Materials with high specific strength and toughness are urgently needed in the fields of electronic packaging, armor, and aerospace. SiC/Al composites show good potential for these applications but the problem of mutual exclusion of strength and toughness still needs to be solved. Herein, we propose a new strategy to simultaneously enhance its strength and toughness from the perspective of structural optimization and interface enhancement. Inspired by the nacre structure, a 3D-(SiC–Si 3 N 4)/Al co-continuous composite was prepared by freeze-casting combined with the pressure infiltration method. During the process, elongated Si 3 N 4 grains were introduced into the ceramic framework to design the internal lamella wall structure and increase the contact area with the aluminum substrate. Moreover, a favorable interfacial bonding was designed between Si 3 N 4 and Al to improve interface wettability. The reliable microstructure of porous 3D-(SiC–Si 3 N 4) preform was tailored through the adjustment of initial solid loading and the α-Si 3 N 4 component. The effects of initial solid loading and the α-Si 3 N 4 component on the microstructure, interfacial wettability, and mechanical properties of the final composites were investigated. The results showed that the SiC–Si 3 N 4 /Al composites possess high flexural strength (769 MPa) and fracture toughness (15.1 MPa m1/2), which is superior to data reported in general literature. Numerous elongated β-Si 3 N 4 grains are produced on the ceramic skeleton, forming an interlocking structure with the aluminum matrix, which increases the contact area with the aluminum substrate. A chemical reaction layer was formed at the interface of the composite, greatly improving the interfacial bonding strength. This work provides a promising design guideline for developing and optimizing high-strength and tough composite. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the efficacy and safety of mulberry twig alkaloids (Sangzhi alkaloids [SZ-A]) in the treatment of type 2 diabetes (T2D).Research Design and Methods: This was a multicenter, randomized, double-blind, double-dummy, and parallel controlled noninferiority clinical trial that was conducted for 24 weeks. A total of 600 patients were randomly allocated to the SZ-A group (n= 360) or acarbose group (n= 240). The primary efficacy end point was the change of glycosylated hemoglobin (HbA1c) compared with baseline. In addition, adverse events (AEs), severe AEs (SAEs), treatment-related AEs (TAEs), and gastrointestinal disorders (GDs) were monitored.Results: After treatment for 24 weeks, the change in HbA1c was -0.93% (95% CI -1.03 to -0.83) (-10.2 mmol/mol [-11.3 to -9.1]) and -0.87% (-0.99 to -0.76) (-9.5 mmol/mol [-10.8 to -8.3]) in the SZ-A and acarbose groups, respectively, and the least squares mean difference was -0.05% (95% CI -0.18 to 0.07) (-0.5 mmol/mol [-2.0 to 0.8]) between the two groups, with no significant difference on the basis of covariance analysis (P > 0.05). The incidence of TAEs and GDs was significantly lower in the SZ-A group than the acarbose group (P < 0.01), but no differences for AEs or SAEs between the two groups were observed (P > 0.05).Conclusions: SZ-A exhibited equivalent hypoglycemic effects to acarbose in patients with T2D. Nevertheless, the incidence of TAEs and GDs was lower following SZ-A treatment than acarbose treatment, suggesting good safety. [ABSTRACT FROM AUTHOR]

We herein describe the synthesis of a new class of axially chiral aza/boracyclophanes (BDN1, BXN1, BDB1 and BXB1) using binaphthyls as chiral building blocks and the main‐group (B/N) chemistry with tunable electronic effects. All macrocycles substituted with triarylamine donors or triarylborane acceptors are strongly luminescent. These macrocycles showed two distinct meta and para π‐conjugation pathways, leading to the formation of quasi figure‐of‐eight and square‐shaped conformations. Interestingly, comparison of such structural models revealed that the former type of macrocycles BXN1 and BXB1 gave higher racemization barriers relative to the other ones. The results reported here may provide a new approach to engineer the optical stability of π‐conjugated chiral macrocycles by controlling π‐substitution patterns. The ring constraints induced by macrocyclization were also demonstrated to contribute to the configurational persistence as compared with the open‐chain analogues p‐BTT and m‐BTT. [ABSTRACT FROM AUTHOR]

• Interfacial interactions of nZVI with clay minerals were analyzed and clarified. • Macromolecular-coated nZVI was in a reversible aggregation with clay minerals. • nZVI were primarily deposited onto the edge sites and Al O faces of clay minerals. • Complexation and van der Waals forces regulated nZVI-clay mineral aggregation. • Hydrogen bonds and van der Waals forces were for coated nZVI hetero-aggregation. The environmental transport and fate of nanoscale zero-valent iron particles (nZVI) in soil and groundwater can be altered by their hetero-aggregation with clay mineral particles (CMP). This study examines the interactions between bare or carboxymethyl cellulose (CMC)-coated nZVI with typical CMP, specifically kaolinite and montmorillonite. Methods include co-settling experiments, aggregation kinetic studies, electron microscopy, Derjaguin–Landau–Verwey–Overbeek (DLVO) and extended DLVO (EDLVO) energy analysis, and density functional theory calculations, focusing on the pH dependency of these interactions. The EDLVO theory effectively described the interactions between nZVI and CMP in aquatic environments. Under acidic conditions (pH 3.5), the interfacial interaction between bare nZVI and kaolinite is regulated by van der Waals forces, while complexation, van der Waals forces, and electrostatic attraction govern the interaction of bare nZVI with montmorillonite, primarily depositing on the Si O face. In contrast, the positively charged Al O face and edge of CMP are the main deposition sites for CMC-coated nZVI through hydrogen bonding, van der Waals forces, and electrostatic attraction. At neutral (pH 6.5) and alkaline (pH 9.5) conditions, both bare and CMC-coated nZVI predominantly attach to the Al O face and edge, facilitated by complexation or hydrogen bonding, alongside van der Waals forces. The attachment of CMC-coated nZVI to CMP surfaces shows reversible aggregation or deposition due to the steric repulsion from the CMC coating. These findings hold significant implications for the environmental applications and risk of nZVI. [Display omitted] [ABSTRACT FROM AUTHOR]

Background. Numerous studies suggested that chronic pain and depression were closely related and widespread in the population. When patients have symptoms of chronic pain and depression, the corresponding treatment will become difficult. Acupuncture, a unique therapeutic method of traditional Chinese medicine, has been reported to potentially serve as an alternative treatment for patients with comorbid chronic pain and depression by many research studies. Methods. A comprehensive search was conducted through the online database, including the Cochrane Library, PubMed, EMBASE, SinoMed, CNKI, and Wanfang database. Trials were RCTs published in the English or Chinese language, recruiting participants with chronic pain and depression comorbidity. The primary outcomes were the Visual Analogue Scale (VAS) and Hamilton Depression Scale (HAMD). Statistical analyses were conducted using Review Manager 5.3. Each trail was quality appraised with the five-point Jadad Score. Results. 7 eligible RCTs involving 535 patients were included. Better therapeutic effect and safety could be observed in the experimental group compared with the control group. There was a significant decrease in the VAS (mean difference (MD) = −0.68 (−1.24, −0.12), P = 0.02) and HAMD (MD = −2.18 (−3.09, −1.26), P < 0.00001) scores and the incidence of adverse events between two groups. Conclusion. In the treatment of chronic pain with depression, acupuncture could not only get better clinical efficacy, but also have higher security compared with medicine therapy, which can be used in patients with poorer response to the conventional medication or suffering from serious side effects. [ABSTRACT FROM AUTHOR]

Background. Diabetic cognitive impairment (DCI), a serious complication of diabetes mellitus (DM), is gaining more acceptance and attention. The learning and memory function of diabetics always decreases. Traditional Chinese medicine (TCM) has been demonstrated to be effective in treating the symptoms in China, and thereinto Chinese medicinal herbs (CMH) are the most widely used. The objective of the present study was to review and analyze the existing data about reducing the symptoms in CMH treatment for DCI. Methods. Electronic literature databases (PubMed, EMBASE, CNKI, SinoMed, and Wan fang) were searched for randomized controlled trials conducted in China, comparing CMH with western medicines in the treatment of DCI, up to April 1, 2018. We applied standard meta-analytic techniques to analyze data from papers that reached acceptable criteria. Result. Nine randomized controlled trials (n = 576) on CMH were included. We found moderate evidence that CMH used alone or in combination with western medicines was more effective than western medicines alone in reliving the symptoms for DCI (total effective rate, odds radio (OR) = 4.64 (2.60, 8.29), and 95% confidence interval, P<0.00001). Besides, CMH along or in combination with western medicines showed more beneficial effects on Montreal Cognitive Assessment (MoCA) scale (mean difference (MD) = 1.31(0.75, 1.87), P<0.00001), Mini-Mental State Examination (MMSE) scale (MD = 2.07 (0.86, 3.28), P<0.00001, and TCM symptom score (TCMSS) (MD = -4.89 (-8.44, -1.34), P = 0.007). Most of the included studies showed that there was not a significant difference in the adverse events. Conclusions. These findings demonstrated that CMH used alone or in combination with western medicines were apparently better than western medicines alone in the treatment of DCI. Because of the poor quality of the studies that were available for the present meta-analysis, further researches are still needed to support these early findings. [ABSTRACT FROM AUTHOR]

Background Despite the high co-morbidity of depressive symptoms in patients with multiple somatic symptoms, the validity of the 9-item Patient Health Questionnaire (PHQ-9) has not yet been investigated in Chinese patients with multiple somatic symptoms. Methods The multicenter cross-sectional study was conducted in ten outpatient departments located in four cities in China. The psychometric properties of the PHQ-9 were examined by confirmative factor analysis (CFA). Criterion validation was undertaken by comparing results with depression diagnoses obtained from the Mini International Neuropsychiatric Interview (MINI) as the gold standard. Results Overall, 491 patients were recruited of whom 237 had multiple somatic symptoms (SOM+ group, PHQ-15≥10). Cronbach׳s α of the PHQ-9 was 0.87, 0.87, and 0.90 for SOM+ patients, SOM− patients, and total sample respectively. All items and the total score were moderately correlated. The factor models of PHQ-9 tested by CFA yielded similar diagnostic performance when compared to sum score estimation. Multi-group confirmatory factor analysis based on unidimensional model showed similar psychometric properties over the groups with low and high somatic symptom burden. The optimal cut-off point to detect depression in Chinese outpatients was 10 for PHQ-9 (sensitivity=0.77, specificity=0.76) and 3 for PHQ-2 (sensitivity=0.77, specificity=0.74). Limitations Potential selection bias and nonresponse bias with applied sampling method. Conclusions PHQ-9 (cut-off point=10) and PHQ-2 (cut-off point=3) were reliable and valid to detect major depression in Chinese patients with multiple somatic symptoms. [ABSTRACT FROM AUTHOR]

: BackgroundChinese herbal medicines are commonly used to improve general health and well-being despite limited scientific data to support their efficacy. We conducted a randomized, double-blind, placebo-controlled trial to determine whether an herbal remedy that is used widely in China was associated with changes in quality of life, energy, memory, sexual function, and qi (the Chinese concept of “vital energy” that is important in general health).: MethodsResidents (n = 237) of Beijing, China, who were aged ≥60 years and had self-reported decreased energy, memory, or sexual function, were randomly assigned to take four tablets of a Chinese herbal formula or of an identical placebo, three times a day for 30 days. Patients returned for one follow-up visit after 30 days for assessment of all outcomes. The main outcome measures were changes in quality of life at 30 days as measured by the 12-Item Short Form Health Survey (SF-12) Mental and Physical Component Summary scales.: ResultsUse of Chinese herbs was associated with a small benefit in the Mental Component scale (difference of 1.9 points; 95% confidence interval [CI]: 0.1 to 3.6) and no benefit in the Physical Component scale (difference of –0.1 points; 95% CI: –1.7 to 1.5) as compared with placebo. A small improvement in the qi scale was no longer significant after adjusting for baseline differences in this score between groups. There was no improvement in physical performance, memory, or sexual function. The herbal product was well tolerated.: ConclusionShort-term use of a mixture of Chinese herbs was associated with a small benefit in one measure of mental health that is of unclear clinical importance. [Copyright &y& Elsevier]

• The root color of Salvia miltiorrhiza determined by the content of tanshinone. • The simultaneous downregulation of the expression of several key genes leading to the decrease of tanshinone content in Salvia miltiorrhiza root. • Identified several candidate cytochrome P450 genes for tanshinone synthesis. • 22 transcription factors that may be involved in the regulation of tanshinone synthesis. Tanshinones are a class of bioactive components and pigments found in the traditional Chinese herb Salvia miltiorrhiza (S. miltiorrhiza). To clarify the biosynthesis of tanshinones in S. miltiorrhiza roots, the metabolome and transcriptome were compared among three S. miltiorrhiza lines (two red root lines: HG and CK, one white root line: BG). In this study, 18 tanshinones showed markedly lower abundances in BG lines than in other lines and 15 significant differentially accumulated metabolites (DAMs) were chosen as potential marker compounds. Meanwhile, the expression of 5 tanshinone biosynthesis genes in BG was significantly downregulated, which affected the metabolic flow of tanshinones. We speculated that this was the reason BG exhibited white roots. Moreover, 49 cytochrome P450 genes and 22 transcription factors were identified as candidate genes for tanshinone synthesis and regulation. Our results not only explain the formation of root color in S. miltiorrhiza , but also provide an effective solution to explore the biosynthetic pathway of tanshinones. [ABSTRACT FROM AUTHOR]

Unfortunately, after publication of this article [1], it was noticed that the affiliation of Rainer Schaefert is incorrectly displayed as, “Department of General Internal Medicine and Psychosomatics, University Hospital Heidelberg, Heidelberg, Germany”. The correct affiliation should read, “Department of Psychosomatics, Medical Division, University Hospital Basel, Basel, Switzerland” and can be seen in the author details of this correction. [ABSTRACT FROM AUTHOR]