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This paper attempts to address the trajectory following control problem of nonholonomic mobile AGV by proposing an improved sliding mode control approach in which, based on the kinematics and attitude deviations established for AGV, the motion characteristics are analyzed and a backstepping sliding mode control with a novel reaching law is designed. This reaching law integrates the merits of the power and exponential reaching laws and promotes the convergence rates of tracking errors. Moreover, with the improved sliding mode controller, the asymptotic stability of tracking deviations can be strictly guaranteed. The simulations have demonstrated the effectiveness and superiority of the proposed approach for mobile AGV.

Cardiovascular diseases (CVDs) pose a serious threat to human health, which are characterized by high disability and mortality rate globally such as myocardial infarction (MI), atherosclerosis, and heart failure. Although stem cells transplantation and growth factors therapy are promising, their low survival rate and loss at the site of injury are major obstacles to this therapy. Recently, the development of hydrogel scaffold materials provides a new way to solve this problem, which have shown the potential to treat CVD. Among these scaffold materials, environmentally responsive hydrogels have great prospects in repairing the microenvironment of cardiovascular tissues and vascular regeneration. They provide a new method for the treatment of cardiovascular tissue repair and space-time control for the release of various therapeutic drugs, including small-molecule drugs, growth factors, and stem cells. Herein, this article reviews the occurrence and current treatment of CVD, as well as the repair of cardiovascular injury by several environmental responsive hydrogels systems currently used, mainly focusing on the delivery of growth factors or the application of cell therapy to revascularization. In addition, we will also discuss the enormous potential and personal perspectives of environmentally responsive hydrogels in cardiovascular repair.

Background The retinoid isomerohydrolase RPE65 has received considerable attention worldwide since a successful clinical gene therapy was approved in 2017 as the first treatment for vision loss associated with RPE65-mediated inherited retinal disease. Identifying patients with RPE65 mutations is a prerequisite to assessing the patients’ eligibility to receive RPE65-targeted gene therapies, and it is necessary to identify individuals who are most likely to benefit from gene therapies. This study aimed to investigate the RPE65 mutations frequency in the Chinese population and to determine the genetic and clinical characteristics of these patients. Results Only 20 patients with RPE65 mutations were identified, and RPE65 mutations were determined to be the 14th most common among all patients with genetic diagnoses. Ten novel variants and two hotspots associated with FAP were identified. A literature review revealed that a total of 57 patients of Chinese origin were identified with pathogenic mutations in the RPE65 gene. The mean best Snellen corrected visual acuity was worse (mean 1.3 ± 1.3 LogMAR) in patients older than 20 years old than in those younger than 15 years old (0.68 ± 0.92 LogMAR). Bone spicule-like pigment deposits (BSLPs) were observed in six patients; they were older than those without BSLP and those with white-yellow dots. Genotype–phenotype analysis revealed that truncating variants seem to lead to a more severe clinical presentation, while best corrected visual acuity testing and fundus changes did not correlate with specific RPE65 variants or mutation types. Conclusions This study provides a detailed clinical-genetic assessment of patients with RPE65 mutations of Chinese origin. These results may help to elucidate RPE65 mutations in the Chinese population and may facilitate genetic counseling and the implementation of gene therapy in China.

Chronic intestinal pseudo-obstruction (CIPO) syndromes are heterogeneous gastrointestinal disorders, caused by either neuropathy or myopathy, resulting in compromised peristalsis and intestinal obstruction. CIPO can have a profound impact on quality of life, leading the most severely affected individuals to life-long parenteral nutrition and urinary catheterization. To search for disease causing gene(s), we performed the whole exome sequencing (WES) in both eight sporadic and two familial cases, followed by targeted sequencing in additional CIPO patients. After identifying a heterozygous missense variant in the ACTG2 gene in one of 10 patients undergone WES, targeted Sanger sequencing of this gene allowed to detect heterozygous missense variants in 9 of 23 further patients with either megacystis-microcolon-intestinal hypoperistalsis syndrome or intestinal pseudo-obstruction. Variants thus identified, one of which still unreported, affect highly conserved regions of the ACTG2 gene that encodes a protein crucial for correct enteric muscle contraction. These findings provided evidence for a correlation between the clinical phenotype and genotype at the ACTG2 locus, a first step to improve the diagnosis and prognosis of these severe conditions.

Geometric confinement is a promising method for the reconstruction of silk fibroin to form diversified structures with excellent mechanical properties. To accomplish geometric confinement, a water vapor assistant embossing process is used with porous anodic aluminum oxide templates, yielding silk fibroin nanopillars with diameters ranging from 40 nm to 130 nm. The elastic modulus of the regenerated silk fibroin nanopillars is investigated with atomic force microscopy nanoindentation analysis. Compared to films with the same treatment conditions, geometric confinement provided a twofold increase in elastic modulus in embossed silk fibroin nanopillars, indicating that β-sheet crystal ordering occurred during the water vapor assistant embossing process. These results demonstrate the feasibility and mechanical property enhancement of the embossing method to fabricate silk nanostructures, and will be useful in designing miniaturized devices.

Samples in the pseudoternary lead-free piezoelectric ceramic system 0.94KNN-(0.06 − x)LiSbO3-x(Bi0.5Ag0.5)ZrO3 were prepared using a solid-state reaction technique and their phase transition behavior and electrical properties studied. Results showed that BAZ diffuses into KNN-LS to form a new solid solution, and induces a phase transition from tetragonal to rhombohedral phase with increase of x. At 0.02 ≤ x ≤ 0.03, coexistence of tetragonal and rhombohedral phases is observed, and enhanced piezoelectric properties are achieved in this composition range due to the polymorphic phase transition near room temperature. Doping with (Bi0.5Ag0.5)ZrO3 effectively promotes densification and further enhances the piezoelectric and dielectric properties of of the ceramics. Moreover, the ceramic with x = 0.025 possesses excellent electrical properties of kp = 42.3%, \({d_{33}^{*}}\) = 320 pm/V and d33 = 235 pC/N, tan δ = 0.039, and Tc = 326°C. This result indicates that 0.94KNN-0.035LS-0.025BAZ ceramic is a promising lead-free material for practical applications.

BiVO4–Bi2O3 p–n heterojunction composites have been prepared via a facile one-step hydrothermal method. X-ray diffraction revealed the as-obtained composites are composed of BiVO4 and Bi2O3 both with monoclinic structures. Subsequently, the photocatalytic activity of composites was evaluated by degradation of Rhodamine B under visible light irradiation. The results indicated that the photocatalytic activity of BiVO4–Bi2O3 composites (BV-1.3) was approximately 3 times higher than that of pure BiVO4. The enhanced photocatalytic property may mainly due to the high separation efficiency of electron–hole pairs caused by the p–n heterojunction.

Background Trimethylaminuria (TMAU) is a genetic disorder whereby people cannot convert trimethylamine (TMA) to its oxidized form (TMAO), a process that requires the liver enzyme FMO3. Loss-of-function variants in the FMO3 gene are a known cause of TMAU. In addition to the inability to metabolize TMA precursors like choline, patients often emit a characteristic odor because while TMAO is odorless, TMA has a fishy smell. The Monell Chemical Senses Center is a research institute with a program to evaluate people with odor complaints for TMAU. Methods Here we evaluated ten subjects by (1) odor evaluation by a trained sensory panel, (2) analysis of their urine concentration of TMA relative to TMAO before and after choline ingestion, and (3) whole exome sequencing as well as subsequent variant analysis of all ten samples to investigate the genetics of TMAU. Results While all subjects reported they often emitted a fish-like odor, none had this malodor during sensory evaluation. However, all were impaired in their ability to produce >90% TMAO/TMA in their urine and thus met the criteria for TMAU. To probe for genetic causes, the exome of each subject was sequenced, and variants were filtered by genes with a known (FMO3) or expected effect on TMA metabolism function (other oxidoreductases). We filtered the remaining variants by allele frequency and predicated functional effects. We identified one subject that had a rare loss-of-function FMO3 variant and six with more common decreased-function variants. In other oxidoreductases genes, five subjects had four novel rare single-nucleotide polymorphisms as well as one rare insertion/deletion. Novel in this context means no investigators have previously linked these variants to TMAU although they are in dbSNP. Conclusions Thus, variants in genes other than FMO3 may cause TMAU and the genetic variants identified here serve as a starting point for future studies of impaired TMA metabolism. Electronic supplementary material The online version of this article (doi:10.1186/s12881-017-0369-8) contains supplementary material, which is available to authorized users.

A 7.7---12 GHz fully monolithic transformer-coupled cascode power amplifier (PA) was designed for X-band phase array radar application. This PA was fabricated in a 0.25-$$\upmu $$μm SiGe BiCMOS technology with chip size of $$2\times 2$$2×2 mm$$^{2}$$2. The best choice of the cascode topology for PA design is discussed and the possible stability issue of this configuration is analyzed. The distributed capacitor structure which is connected to the base of cascode transistor is proposed to reduce the base series inductance and hence, improve circuit stability and boost gain. Moreover, circuit/layout co-design for above structure is completed through full 3D simulation. The PA features a three-stage cascode architecture that includes both medium-speed (medium breakdown voltage) and high breakdown voltage (low-speed) SiGe transistors, and a 1:2 input splitter and a 4:1 output combiner which are designed for a low insertion loss and compact dimensions on-chip. The proposed PA achieves a measured small signal gain of 26.6---29.6 dB from 7.7 to 12 GHz with a 5.0 V DC supply. A 28 dBm maximum output power with an 18.5 % power-added efficiency at 10 GHz have also been achieved.

A 5 GHz transformer-feedback power oscillator with novel frequency modulation (FM) up to 10 MHz is presented in this paper. The novel FM is achieved by a CMOS transistor between transformer and ground, which is designed for varying the equivalent inductance and mutual inductance of the transformer and shows no DC connection with the oscillation circuit. The major frequency tuning is realized by the variable capacitor which is controlled by a phase lock loop. The RF VCO with 210 MHz tuning range operates in class-E mode to achieve a cost-effective transmitter, which demonstrates a high DC-to-RF conversion efficiency of 39 %. A RF power of 15.1 dBm and phase noise better than $$-$$ - 109 dBc/Hz @ 100 kHz from the central frequency of 5.5 GHz is obtained with the biasing conditions V $$_\mathrm{ds}$$ ds = 1.8 V and V $$_\mathrm{gs}$$ gs = 0.65 V. The VCO also demonstrates an ultra-low voltage operation capability: with V $$_\mathrm{ds}$$ ds = V $$_\mathrm{gs}$$ gs = 0.6 V and DC power consumption of 9 mW, the output power is 4.5 dBm and the phase noise better than $$-$$ - 93 dBc/Hz @ 100 kHz. The die size of the transformer-feedback power oscillator is only $$0.4\times 0.6$$ 0.4 × 0.6 mm $$^{2}$$ 2 .

Measurement uncertainty although introduced to medical laboratories some years ago, this concept is not familiar to all medical researchers, especially for the measurement of biological samples. Therefore, it is important to highlight the evaluation and expression of measurement uncertainty using a practical example. In accordance with published procedures for evaluating and expressing uncertainty, we analyzed the sources of uncertainty in the determination of repaglinide in human plasma using liquid chromatography–tandem mass spectrometry (LC–MS/MS). We investigated each component of uncertainty and calculated the combined and expanded uncertainties. We evaluated the uncertainty associated with repeatability, weighing, purity, solution and sample preparation, recovery, calibration fitting, and temperature. The expanded uncertainty for low, medium, and high concentrations of repaglinide was 0.090, 0.25, and 3.16 ng/mL, respectively (p = 95 %, k = 2). This example provides an important reference for the evaluation of uncertainty in biological sample determinations using LC–MS/MS and human plasma and will be helpful in explaining the reliability of test results.

Absence of the anterior (ACL) or posterior cruciate ligament (PCL) are rare congenital malformations that result in knee joint instability, with a prevalence of 1.7 per 100,000 live births and can be associated with other lower-limb abnormalities such as ACL agnesia and absence of the menisci of the knee. While a few cases of absence of ACL/PCL are reported in the literature, a number of large familial case series of related conditions such as ACL agnesia suggest a potential underlying monogenic etiology. We performed whole exome sequencing of a family with two individuals affected by ACL/PCL. We identified copy number variation (CNV) deletion impacting the exon sequences of CEP57L1, present in the affected mother and her affected daughter based on the exome sequencing data. The deletion was validated using quantitative PCR (qPCR), and the gene was confirmed to be expressed in ACL ligament tissue. Interestingly, we detected reduced expression of CEP57L1 in Epstein–Barr virus (EBV) cells from the two patients in comparison with healthy controls. Evaluation of 3D protein structure showed that the helix-binding sites of the protein remain intact with the deletion, but other functional binding sites related to microtubule attachment are missing. The specificity of the CNV deletion was confirmed by showing that it was absent in ~700 exome sequencing samples as well as in the database of genomic variations (DGV), a database containing large numbers of annotated CNVs from previous scientific reports. We identified a novel CNV deletion that was inherited through an autosomal dominant transmission from an affected mother to her affected daughter, both of whom suffered from the absence of the anterior and posterior cruciate ligaments of the knees.

Undoped LaAlO3 and 1 at.% Ce:LaAlO3 single crystals were grown by the Czochralski process. Absorption and fluorescence spectra were measured at room temperature. Detailed energy levels structure of Ce:LaAlO3 was determined. In this paper, two viewpoints were provided. The first one is: the energy levels structure of Ce:LaAlO3 is very similar to that of Ce:Lu2(SiO4)O which is a well-known scintillator. In the energy levels structure of Ce:LaAlO3 and Ce:Lu2(SiO4)O, the lowest 5d energy level of Ce3+ is located below the bottom of the conduction band of host crystal and the other higher 5d energy levels of Ce3+ are located above the bottom of the conduction band of host crystal. The second one is: Ce:LaAlO3 single crystal may not be suitable for scintillation application; by comparing the energy levels structures of Ce:LaAlO3 and Ce:Lu2(SiO4)O, the large energy difference (1.13 eV) between the two lowest 5d energy levels of Ce3+ in LaAlO3 is a crucial factor that causes the luminescence quenching.