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BackgroundAccumulating evidence has linked dyslipidemia during pregnancy to the risk of delivering infants born either large for gestational age (LGA) or small for gestational age (SGA). However, the effects of the vitamin D status on these relationships require further investigation. This study investigated whether the relationship between lipid profiles and the risk of LGA or SGA was influenced by vitamin D levels during the second trimester.MethodsMaternal lipid profile levels, including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and vitamin D levels, were measured in a cohort of 6,499 pregnant women during the second trimester. Multivariate regression models and subgroup analyses were employed to evaluate the potential associations between maternal lipid profiles, vitamin D levels, and the risk of LGA or SGA.ResultsThe prevalence of SGA infants was 9.8% (n=635), whereas that of LGA infants was 6.9% (n=447). Maternal TG levels were found to be positively associated with the risk of LGA (odds ratio [OR] = 1.41, 95% confidence interval [CI]:1.17–1.70), whereas a negative association was observed between maternal TG, TC, LDL-C levels, and risk of SGA. Additionally, mothers with higher HDL-C levels were less likely to give birth to an LGA infant (OR=0.58, 95% CI:0.39–0.85). Importantly, associations between TG, TC, LDL-c, and SGA as well as between TG and LGA were primarily observed among pregnant women with insufficient vitamin D levels. As for HDL-C, the risk of LGA was lower in mothers with sufficient vitamin D (OR = 0.42, 95% CI:0.18–0.98) compared to those with insufficient vitamin D (OR = 0.65, 95% CI:0.42–0.99).ConclusionVitamin D status during the second trimester exerts a modifying effect on the association between lipid profiles and the risk of LGA and SGA infants.

The 0.5Y2O3/Al2O3-Cu/30Mo3SiC and 0.3GO-0.5Y2O3/Al2O3-Cu/30Mo3SiC composites were fabricated by fast hot press sintering. Hot compression tests of the composites were carried out using the Gleeble-1500 simulator at 0.001–10 s−1 strain rates and 650–950 °C deformation temperatures. The effects of doped reduced graphene oxide (rGO) on the hot deformation behavior and microstructure of 0.5Y2O3/Al2O3-Cu/30Mo3SiC composites were investigated. Trace of molybdenum carbide (MoC) layers/nanoparticles formed in-situ at the rGO-Cu/Mo interface, which is beneficial to the interfacial bonding of the composite. The enhanced flow stress and activation energy of hot deformation is attributed to the addition of the rGO. The activation energy of the composites was improved by 11% with the addition of rGO. The dislocation density and texture orientation ratio decrease at higher deformation temperatures.

The Cu–Ni–Sn–Ti–Cr and Cu–Ni–Sn–Ti–Cr–Ce alloys were compressed at 500–900 °C with 0.001–10 s−1 strain rates using the Gleeble 1500 deformation simulator. The effects of Ce addition on the microstructure and recrystallized grains of Cu–Ni–Sn–Ti–Cr alloy were investigated using EBSD and TEM. A constitutive equation was established to calculate the activation energy for the alloy hot deformation, and the optimal processing parameters were obtained. The corresponding texture of the Cu–Ni–Sn–Ti–Cr–Ce alloy deformed at 800 °C with 0.01 s−1, 0.1 s−1 and 1 s−1 strain rates is the {112} Copper, {001} Cubic and {011} Goss texture. The texture of the Cu–Ni–Sn–Ti–Cr alloy deformed at 800 °C and 0.1 s−1 strain rate is the {011} Goss texture. The strain rate and Ce addition can change the alloy texture. The precipitation phase in Cu–Ni–Sn–Ti–Cr (-Ce) alloy is mainly CuNi2Ti phase, and the addition of Ce can promote the precipitation of fine nanoscale precipitation phase in the alloy. Moreover, the addition of Ce can promote the dynamic recrystallization of the alloy, but the dynamic recrystallization of the alloy is suppressed with the increase of the hot deformation rate at the heat deformation temperature of 800 °C.

The aim of this study is to observe the organization and properties of Al2O3–Cu/WSiC–Y2O3 composites and to investigate the effect of Y2O3 incorporation on the electrical contact properties of the composites. Preparation of Al2O3–Cu/30W3SiC(0.5Y2O3) composites by rapid hot-pressing sintering technique. The conductivity of the composites is 59.3 %IACS and 58.3 %IACS, respectively. Hardness is 179 HV and 183 HV, respectively. Thermal conductivity is 108 W/(m·k) and 275 W/(m·k), respectively. The dense structure of the composites and the homogeneous distribution of reinforcing phases give the composites excellent overall performance. The addition of Y2O3 increases the resistance of the materials to arc erosion. The amount of material transfer and loss is significantly reduced, and the arc ablation phenomenon is reduced. The arc duration was significantly reduced from 4.48 ms to 0.44 ms, 5.72 ms–4.68 ms, 6.23 ms–5.52 ms, and 12.5 ms–8.59 ms, respectively; and the melt force was significantly reduced to 58.9%, 81.4%, 87.5%, and 89.4% of the original.

Biotinidase (BTD) deficiency (OMIM 253260) is an autosomal recessively inherited metabolic disorder resulting from deficient activity of the BTD enzyme, which can cleave and release biotin from a variety of biotin-dependent carboxylases, and is therefore recognized as a tool to recycle biotin. Being a condition caused by variations on BTD gene with a consequence of free biotin shortage, BTD deficiency may impair the activity of biotin-dependent carboxylases, and thus bring about a buildup of potentially toxic compounds in the body, primarily 3-hydroxyisovaleryl-carnitine in plasma as well as 3-hydroxyisovaleric acid in urine. The phenotype of BTD deficiency may vary dramatically, from asymptomatic adults to severe neurological anomalies, even death in infancy. In the present study, we reported on a 5-month-old boy, whose parents sought for medical consultation in our clinic for their son due to his loss of consciousness, repeated tetany, and motor retardation. Detailed clinical features included severe psychomotor retardation, hypotonia, as well as failure to thrive. The brain MRI at 12 months showed cerebellar hypoplasia and multiple foci of leukodystrophy. The result of antiepileptic therapy was not satisfying. During hospitalization, BTD deficiency was suggested by elevated concentration of 3-hydroxyisovaleryl-carnitine in the blood spots and 3-hydroxyisovaleric acid in the urine. The child was then diagnosed with profound BTD deficiency based on the above findings and low BTD enzyme activity. Subsequent mutational analysis revealed a novel homozygous variant, c.637_637delC (p.H213Tfs*51) in exon 4 of BTD gene in the proband, which was recognized as a further support to the diagnosis. Therefore, biotin treatment was started immediately, eventually with satisfactory outcomes achieved in terms of prevention of epileptic seizure, performance in deep tendon reflexes, and improvement of muscular hypotonia, but unfortunately, the therapy failed to show any evident effects on poor feeding and intellectual disability. This painful lesson suggests that newborn screening for inherited metabolic diseases is essential for early identification and treatment, which should have been performed in this case to avoid this tragedy.

BackgroundSevere hyperlipidemia is characterized by markedly elevated blood triglyceride levels and severe early-onset cardiovascular diseases, pancreatitis, pancreatic necrosis or persistent multiple organ failure if left untreated. It is a rare autosomal recessive metabolic disorder originated from the variants of lipoprotein lipase gene, and previous studies have demonstrated that most cases with severe hyperlipidemia are closely related to the variants of some key genes for lipolysis, such as LPL, APOC2, APOA5, LMF1, and GPIHBP1. Meanwhile, other unidentified causes also exist and are equally worthy of attention.MethodsThe 29-day-old infant was diagnosed with severe hyperlipidemia, registering a plasma triglyceride level as high as 25.46 mmol/L. Whole exome sequencing was conducted to explore the possible pathogenic gene variants for this patient.ResultsThe infant was put on a low-fat diet combined with pharmacological therapy, which was successful in restraining the level of serum triglyceride and total cholesterol to a low to medium range during the follow-ups. The patient was found to be a rare novel homozygous duplication variant-c.45_48dupGCGG (Pro17Alafs*22) in GPIHBP1 gene-leading to a frameshift which failed to form the canonical termination codon TGA. The mutant messenger RNA should presumably produce a peptide consisting of 16 amino acids at the N-terminus, with 21 novel amino acids on the heels of the wild-type protein.ConclusionsOur study expands on the spectrum of GPIHBP1 variants and contributes to a more comprehensive understanding of the genetic diagnosis, genetic counseling, and multimodality therapy of families with severe hyperlipidemia. Our experience gained in this study is also contributory to a deeper insight into severe hyperlipidemia and highlights the importance of molecular genetic tests.

The manipulation of multiple physical connected objects can be described by virtual connected string system. We proposed a Lyapunov-based stabilization control approach for virtual connected string with midway discontinue vertical force. The system is with Riemannian boundary. We use the backstepping method to transform the system into a stable system with Dirichlet boundary. In this way, we get the controller to make sure the closed-loop system converge to the zero point exponentially. Then, we construct a Lyapunov function to analyze the stability for the closed-loop system. We also show the system is well-posedness. Also, we use the active disturbance rejection control (ADRC) to reject the disturbance when disturbance is present. Some numerical stimulations show that the control law is the effective.

Considering the characteristics of equipment on underground fully mechanized coal mining face, a multirobot system, which takes heavy-duty mobile support robot (HMSR) as the pushing robot and middle trough (MT) as the manipulated object, is established. To overcome the problem of unstable communication and potential pressure loss, a memory-pushing fuzzy control strategy is proposed to achieve better practical performance without human-guided operations. The pushing dynamics without communication is derived to proof the convergence of the dynamic system, and the time-based memory-pushing fuzzy model is built for compensating the potential pressure loss. Finally, the proposed control strategy is simulated in virtual environment, which integrates our pushing dynamics, and an industrial experiment is demonstrated as well. Both the simulation and industrial experiments show the efficiency and feasibility of the proposed method.

Pose estimation is one of the most complicated and compromising problems for underground mining machine tracking, and it is particularly important for hydraulic support autonomous following mining machine (AFM) policy-making system. In this paper, a low-cost infrared vision-based system through an Efficient Perspective-n-Point (EPnP) algorithm is proposed. To improve efficiency and simplify computation, a traditional EPnP algorithm is modified through a nature-inspired heuristic optimization algorithm. The optimized algorithm is integrated into the AFM policy-making system to estimate the relative pose (R-Pose) estimation between hydraulic support and the mining machine’s shearer drum. Simple yet effective numerical simulations and industrial experiments were carried out to validate the proposed method. The pose estimation error was ≤1% under normal lighting and illuminance, and ≤2% in a simulated underground environment, which was accurate enough to meet the needs of practical applications. Both numerical simulation and industrial experiment proved the superiority of the approach.

To improve the operating performance of robots’ end-effector, a humanoid robot hand based on coupling four-bar linkage was designed. An improved transmission system was proposed for the base joint of the thumb. Thus, a far greater motion range and more reasonable layout of the palm were obtained. Moreover, the mathematical model for kinematics simulation was presented based on the Assur linkage group theory to verify and optimize the proposed structure. To research the motion relationships between the fingers and the object in the process of grasping object, the grasping analysis of multi-finger manipulation was presented based on contact kinematics. Finally, a prototype of the humanoid robot hand was produced by a three-dimensional printer, and a kinematics simulation example and the workspace solving of the humanoid robot hand were carried out. The results showed that the velocities of finger joints approximately met the proportion relationship 1:1:1, which accorded with the grasping law of the human hand. In addition, the large workspace, reasonable layout, and good manipulability of the humanoid robot hand were verified.

In order to improve the flattening quality of sheet metal with free-form surface, a flattening system was developed. The system framework was proposed and the key technologies such as mesh quality measuring criterion, center triangle indexing algorithm, coordinate transforming principle, and initial flattening method were elaborated. Moreover, a planar spring–mass model was presented to optimize the initial flattening result, and the flowchart of the proposed flattening method was designed. Finally, three simulation examples were carried out and the comparison results indicated that the proposed system was proved feasible and efficient.

Interconnected macroporous polymers were prepared by copolymerizing methyl acrylate (MA) via Pickering high internal phase emulsion (HIPE) templates with modified silica particles. The pore structure of the obtained polymer foams was observed by field-emission scanning electron microscopy (FE-SEM). Gas permeability was characterized to evaluate the interconnectivity of macroporous polymers. The polymerization shrinkage of continuous phase tends to form open pores while the solid particles surrounding the droplets act as barriers to produce closed pores. These two conflicting factors are crucial in determining the interconnectivity of macroporous polymers. Thus, poly-Pickering HIPEs with high permeability and well-defined pore structure can be achieved by tuning the MA content, the internal phase fraction, and the content of modified silica particles. [ABSTRACT FROM AUTHOR]

Interconnected macroporous polymers were prepared by copolymerizing methyl acrylate (MA) via Pickering high internal phase emulsion (HIPE) templates with modified silica particles. The pore structure of the obtained polymer foams was observed by field-emission scanning electron microscopy (FE-SEM). Gas permeability was characterized to evaluate the interconnectivity of macroporous polymers. The polymerization shrinkage of continuous phase tends to form open pores while the solid particles surrounding the droplets act as barriers to produce closed pores. These two conflicting factors are crucial in determining the interconnectivity of macroporous polymers. Thus, poly-Pickering HIPEs with high permeability and well-defined pore structure can be achieved by tuning the MA content, the internal phase fraction, and the content of modified silica particles. [ABSTRACT FROM AUTHOR]

The microencapsulation of phase change materials (n-hexadecane) with double-walled shells (polystyrene/ graphene oxide) was realized from Pickering emulsion templating. Graphene oxide nanosheets were modified by the polycondensate of diethanolamine and adipic acid, which can well stabilize oil-in-water (O/W) Pickering emulsions. The morphology of the double-walled shell of polymer microspheres was observed by scanning electron microscopy (SEM). The thermal and barrier properties of microcapsules were studied using differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and the flammability test. DSC results indicate that the encapsulation ratio of n-hexadecane is as high as 78%. The encapsulated phase change material has good thermal stability, owing to the existence of graphene oxide on the surface protecting the core material from leakage and evaporation. This double-walled microencapsulation of phase change materials may have potential applications in energy storage and energy saving. [ABSTRACT FROM AUTHOR]