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Objective: To analyze the frequency and spectrum of thalassemia mutations in amniotic fluid samples collected from Han and Li people in Hainan province of China. Methods: We carried out a retrospective analysis on prenatal diagnosis of amniotic fluid samples collected from pregnant women who may have next generation with high risks of medium or severe thalassemia between 2005 and 2016. Diverse fetal thalassemia genotypes and mutated alleles in Han and Li people were analyzed and cmpared. Results: We examined 536 amniotic fluid samples from Han people and 588 from Li people, among which 406 Han and 500 Li samples were found to carry at least one thalassemia gene mutation, with a detection rate of 75.75% and 85.03%, respectively. Among all α- and β-thalassemia mutant alleles detected, the most frequently found mutations in Han and Li samples were SEA-type of α-thalassemia and 41/42 (–CTTT) of β-thalassemia, respectively. A total of 75 severe thalassemia cases were identified in Han samples and 53 in Li samples. In most of these severe cases, parents chose to terminate pregnancy after being informed of thalassemia-related risks. Conclusions: The thalassemia mutations shows ethnic and area specificity, and that prenatal diagnosis for high-risk thalassemia carrier pregnant women is an efficient approach to prevent and control the occurrence of severe thalassemia in the high-prevalence areas.

Objective: To study the relationship between umbilical blood flow ultrasound characteristics of perioperative fetal intrauterine hypoxia and maternal as well as fetal oxidative stress injury. Methods: 108 puerperae giving birth in our hospital between May 2014 and October 2016 were selected and divided into normal pregnancy group with neonatal Apgar score >7 points and intrauterine hypoxia group with neonatal Apgar score ≤7 points, color Doppler diasonograph was used to determine umbilical blood flow ultrasound parameters, umbilical cord blood was collected to determine the levels of oxidative stress products, and the placenta was collected to determine the levels of oxidative stress products and related apoptosis molecules. Results: During 24–30 weeks, 31–36 weeks and 37–41 weeks of pregnancy, umbilical blood flow resistance index (RI), pulsatility index (PI) and diastolic velocity/systolic velocity (S/D) of intrauterine hypoxia group were significantly higher than those of normal pregnancy group (P

Reactions of four different tetrazole-containing carboxylic acids with GdCl3·6H2O, produced the coordination compounds, [Gd4(pytza)5(H2O)10(μ-O) Cl]·4H2O·2Cl (1) [pytza = 2-(5-(pyridine-4-yl)-2H-tetrazole-2-yl)acetato], [Gd(pztza)2(H2O)6]·pztza·3H2O (2), [pztza = 2-(5-(pyrazin-2-yl)-2H-tetrazol-2-yl) acetato], [Gd(pmtza)2(H2O)6]Cl·2H2O (3), [pmtza = 2-(5-(pyrimidyl-2-yl)-2H-tetrazol-2-yl) acetato], and Gd(tzpya)2(H2O)5]Cl·4H2O (4) [tzpya = 2-(4-(5H-tetrazol-5-yl)pyridin-1(4H)-yl) acetato]. The compounds were structurally characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. X-ray diffraction analysis reveals that compound 1 displays a 2D single layered network and compounds 2–4 are mononuclear. Compounds 1–4 are self-assembled to form 3D networks by hydrogen bonding interactions. Furthermore, the luminescent properties in the solid state at room temperature were investigated.

Three complexes of bifunctional 5-substituted tetrazolatecarboxylate ligands [2-(5-(pyrazin-2-yl)-2H-tetrazol-2-yl)acetic acid (Hpztza), 3-(5-amino-2H-tetrazol-1(5H)-yl)propanoic acid (Hatzp), and N,N′-bis(tetrazol-5-yl)anime-N2,N2′-diacetic acid (H2datza)], namely a mononuclear structure [La(pztza)2(H2O)5]·4H2O·pztza (1), a 1D polymeric chain structure [La2(atzp)4(H2O)8]·2NO3·2H2O (2), and a 2D layer network [La(datza)(H2O)3]·4H2O (3) were prepared and structurally characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. The structures of these complexes are controlled not only by the number and different coordination modes of the tetrazole-carboxylate ligands but also the different 5-substituents of the tetrazole ring. The complexes show ligand-centered luminescence at room temperature in the solid state. The obvious enhancements in luminescence make these complexes to be the potential materials for optical use.

Hand, foot, and mouth disease (HFMD) spreads rapidly and has been recognized as a public health problem in recent years in China. Unfortunately, there is no effective vaccine or antiviral drug currently for EV71 infection. In this study, we aim to identify biomarker which are associated with for severity of EV71 infection cases using high-throughput RNA sequencing approach. RNA sequencing of samples from severe HFMD (S) patients group (n = 10) and control HFMD (C) patients group (n = 10) were performed and the results were verified by qPCR. mRNA with the highest expression level was selected to be validated in an independent cohort comprising of 45 severe EV71 infected patients and 45 control by qPCR assay. Seventeen significant differentially expressed genes were identified. Scavenger receptor class A, member 3 (SCARA3) was one of the significantly upregulated genes with the highest expression level and was selected for validation. The mean relative expression levels in severe HFMD and control HFMD patients were 10.1-fold and 5.0-fold, respectively, P value

The impacts of operation parameters on agglomeration characteristics during biomass gasification in fluidized bed were studied experimentally in a 0.02MWt CFB gasifier using cotton stalk pellet as fuel. The experimental results indicated that among the temperature range (600 °C-800 °C), bed agglomeration would occur after a period running with sand, high alumina bauxite or periclase as the bed material, and potassium gathered on the surface of bed materials. In the process of the fluidized-bed gasification of biomass, air velocity affected the degree of bed agglomeration, and the agglomeration problem in return valve was more serious than that in main bed.

Sapphire single crystal is widely used in a variety of modern applications from GaN-based LED to military optical systems because of its excellent combination of optical, mechanical, thermal and chemical properties. The dislocations affecting the quality of sapphire crystal were studied by chemical etching and optical microscopy in this paper. The experimental results showed that the dislocation corrosion pits of (11-20) plane in sapphire crystals grown by Kyropoulos method is diamond-shaped and (1-102) plane is isosceles triangle and the density of dislocations in samples grown by Czochralski method is about two orders of magnitude higher than that in samples grown by Vertical Bridgman method. The formation mechanism of defects and proposes was also discussed.

The over-load protective relay is widely used for motor protection. The reliability of the over-load protective relay directly affects the safe running of a motor. The reliability testing and reliability analysis of the over-load protective relay is an important way to improve the reliability of products. In this paper, the reliability test method of the over-load protective relay is studied, and the reliability tests of the typical products are carried out on a reliability tester developed by authors. In terms of the testing results, the reliability analysis is finished. The failure reasons are found and the measures are put forward to improve the reliability of the products.

In modern mechanical systems, especially in robotics and bio-mechanics, there are needs to investigate higher pairs in more details, and to compute the d.o.f. of the relative motion between two bodies, rather than the d.o.f. of the whole system. In this paper, conjugate pairs are investigated with the aid of the theory of conjugate surfaces. This investigation provides a geometrical insight of the d.o.f. of a joint. The conjugation chain and the corresponding algorithm are introduced. They provide an instrumental tool for computing the d.o.f. of the equivalent conjugate motion between two bodies in a mechanical system. The existence of the redundant and the complementary d.o.f. is briefly explained.

A novel adaptive ant colony clustering algorithm based on digraph (A3CD) is presented. Inspired by the swarm intelligence shown through the social insects' self-organizing behavior, in A3CD we assign acceptance weights on the directed edges of a pheromone digraph. The weights of the digraph is adaptively updated by the pheromone left by ants in the seeking process. Finally, strong connected components are extracted as clusters under a certain threshold. A3CD has been implemented and tested on several clustering benchmarks and real datasets to compare the performance with the classical K-means clustering algorithm and LF algorithm which is also based on ACO. Experimental results show that our algorithm is easier to implement, more efficient and performs faster and has better clustering quality than other methods.

An adaptive data clustering algorithm based on ant colony (ant-cluster) is presented. Enlightened by the self-organizing behavior of ant society, we assign acceptance rates on the directed edges of a pheromone digraph in ant-cluster system. The pheromone on the edges of the digraph is adaptively updated by the ants passing it. Some edges with less pheromone are progressively removed under a list of certain thresholds in the process. Strong connected components of the final digraph are extracted as clusters. The performance of ant-cluster is compared with classical K-means clustering algorithm and ACO clustering algorithm LF in terms of clustering quality and efficiency on several real datasets and clustering benchmarks. Experimental results indicate that the ant-cluster is able to find clusters faster with better clustering quality and is easier to implement than K-means and LF.

Two basic features of instantaneous conjugate motion, which distinguishes it from instantaneous free body motion, are pointed out. Their influences on the geometrical constraints requisite for surface/line conjugation are discussed. Their importance in facilitating motion analysis of mechanical systems through linearization of relevant equations is clarified. Two illustrative examples are cited.Copyright © 2002 by ASME

Four fundamental forms for representing rigid body motion, i.e. the rotation-of-vector form, the matrix form, the quaternion form and the screw form, all based on the conventional concept that motion is specified by the movement of a reference point together with an orientation change, are expounded. The inter-relationships among these forms are elucidated. The geometric images of these representation-forms, i.e. the motion mappings, are explained, and an innovative duplex-mapping, a powerful tool for mobility analysis of multi-loop mechanisms and robots, is introduced. An exotic motion representation, based on a concept totally different from the conventional concept, is described. This is a purely geometric representation, a representation by a pair of conjugate curves on respective conjugate surfaces, and is called the conjugation form of motion representation. The conversion from the conjugation form to the rotation-of-vector form and the inverse conversion are described. These conversions, which constitute the essential and featured contents of the Theory of Conjugate Surfaces, have great potential applications in motion design for numerically controlled manufacturing and in surface generation by numerically controlled manufacturing. The basis equations for the conversions, i.e. the three relationship-equations, are deduced. The fundamental equation conjugation, the four conjugato-kinematic entities and the five differential formulas for the inverse conversion are derived.

A new species of the subgenus Digenualea of the genus Neotrombicula Hirst was described from Myospalax baileyi Pallas in Huzhu County, Qinghai Province, China.