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AbstractIn this report, new self-healing hydrogels were obtained through simple one-pot free radical polymerization of acrylamide, phenylboronic acid, and 2-hydroxyethyl acrylate as copolymer monomers, potassium persulfate (KPS) as initiator, and tetramethylethylenediamine (TEMED) as promoter under low-temperature alkaline (pH = 9) conditions. The boronic acid group of phenylboronic acid (PBA) can interact with the hydroxyl group of hydroxyethyl acrylate (HEA) to form dynamic boronic ester bonds instead of the conventional bis acrylate crosslinkers. The effect of PBA content on the mechanical strength of the hydrogels was systematically investigated. The hydrogels exhibited higher stress, elongation, and self-healing properties due to the synergistic effect of H-bonds and boronate-diol complexation. Further studies revealed that the A–H–0.2–P–0.08 hydrogels exhibited excellent resistance to compression fatigue and also showed good biocompatibility through in vitro cytotoxicity tests. [ABSTRACT FROM AUTHOR]

Studies focused on morphological variation are key for chrono- and biostratigraphy. Morphological variability can be induced by biological and taphonomical biases. Their distinction can become a difficult task due to the lack of population control. Here, we analyse three populations belonging to the genus Protoryctocephalus, two populations from China (P. arcticus and P. balangensis) and a third population of P. arcticus from Greenland. Protoryctocephalus balangensis was collected from the lowermost part of the Kaili Formation where fossils are tectonically deformed while P. arcticus from the 'Tsinghsutung' and Greenland specimens are non-deformed. Geometric morphometrics analysis shows that these three populations indeed belong to the same species. However, the large allometry measured in P. balangensis compared with the 'Tsinghsutung' population and the Greenland population, which is represented by meraspid and early holaspid individuals, suggested that the morphological variation is taphonomically controlled and non-biological. The results suggest that Protoryctocephalus arcticus from the 'Tsinghsutung' Formation is suitable for international correlation, and further studies focus on different aspects such as ontogeny, segment development or fluctuating asymmetry and modularity. [ABSTRACT FROM AUTHOR]

Deletional α-thalassemia is characterized by reduced hemoglobin A2 and involves the deletion of a few nucleotides, which is a rare hereditary disease. However, the detection of rare mutations using commonly used genetic tests is highly challenging. In the present study, next-generation sequencing (NGS) was used to identify a novel 7-bp deletion α-thalassemia in one individual from a Chinese family. Hematological parameters of the family members were determined using an automated cell counter, and hemoglobin electrophoresis was performed using a capillary electrophoresis system. Subsequently, NGS was performed on the genomic DNA of the patient and her family members. The 7-bp deletion (named Hb Honghe [HBA1: c.401_407delGCACCGT]) of α-thalassemia in the α-globin gene was confirmed using Sanger sequencing. The patient's father was also a heterozygous carrier of HBA1: c.401_407delGCACCGT deletion, but not her mother or sister. The application of the combined molecular approach is essential for the accurate diagnosis of rare thalassemia. This study reports a novel case of α- thalassemia. The characterization of the mutation might provide new insights into genetic counseling and accurate diagnosis of thalassemia. [ABSTRACT FROM AUTHOR]

Shortly after the cessation of the Cenozoic seafloor spreading in the South China Sea, a period of basaltic magmatism occurred in the Indochina Peninsula. The various types of xenoliths/xenocrysts present in these igneous rocks can provide information about the lithospheric mantle under the Indochina Peninsula. In this study, we present new ages and in situ major and trace element compositions for the xenoliths and olivine xenocrysts from the Wichian Buri and Mae Tha basalt flows in Thailand. The new ages obtained in this study for the Wichian Buri and Mae Tha basalt flows are 9.24 and 2.35 Ma, respectively. Under Thailand, the lithology of the sub-continental mantle lithosphere (SCLM) could be spinel-lherzolite, with a mantle temperature range of 936°C–1096°C. The mantle source of the Cenozoic basalts from Thailand and its adjacent regions could be affect by recycled oceanic crust and carbonates. The origin of spongy textures in clinopyroxene should be resulted from partial melting induced by decompression. SCLM under Thailand were transformed by peridotite-melt interaction, and basaltic melt trapped the mantle xenocryst and xenolith quickly ascended to the surface. [ABSTRACT FROM AUTHOR]

Fresh aquatic products are highly perishable after harvest due to their high water content, high protein level, high endogenous enzyme activity, and high growth rates of microorganism. Drying has been proven a successful preservation method for aquatic products by removing water. The conventional sun drying is energy-saving and environment-friendly, but time-consuming and low efficiency. This paper reviews the recent developments in drying technologies for aquatic products including hot-air drying, heat pump drying, infrared radiation drying, freeze drying, microwave drying and hybrid drying methods, with an emphasis of the advantages for different drying techniques to improve the drying efficiency and product quality. Especially, the advances of innovative detection technologies for the drying process monitoring are analyzed and discussed, including near infrared spectroscopy, computer vision system, hyperspectral imaging, low-field nuclear magnetic resonance and magnetic resonance imaging. These analytical techniques can effectively monitor the quality change and improve the drying quality of the aquatic products. Finally, the development trends of drying technologies and monitoring methods for aquatic product in the future are proposed. [ABSTRACT FROM AUTHOR]

In this paper we are concerned with numerical method for nonhomogeneous Helmholtz equations with variable wave numbers. We derive generalized plane wave basis functions for three-dimensional homogeneous Helmholtz equations with variable wave numbers. Then, by combining the local spectral element method, we design a generalized plane wave discontinuous Galerkin method for the discretization of such nonhomogeneous Helmholtz equations (in both dimensions two and three dimensions). We show that the approximation solutions generated by the proposed discretization method yield error estimates with high accuracies. Numerical results indicate that the resulting approximate solutions generated by the new method possess high accuracy and verify the validity of the theoretical results. [ABSTRACT FROM AUTHOR]

The impact of high-pressure processing (HPP) on dissusion of antioxidant butylated hydroxytoluene (BHT) in polyethylene (PE) was discussed via the molecular dynamics method. Furthermore, the glass transition temperatures (Tg), the accessible free volumes of PE and the diffusion coefficients of BHT in PE at different HPP treatments were calculated, and the diffusion trajectories of the BHT molecules in PE were also presented. Finally, the diffusion mechanism of BHT in PE under HPP was analyzed based on the aforementioned simulation results. The results show that theTgof PE increases under high pressure while the fractional free volume (FFV) reduces, and the diffusion coefficient decreases with the pressure on the rise. The diffusion trajectories of BHT in PE under HPP indicate that the BHT molecules are trapped and slowly wriggle in a narrow path among PE molecular chains due to the extreme high pressure. However, the high temperature has an opposite effect on the diffusion behavior of BHT in PE compared with high pressure. As the temperature rises, the FFV of PE and the diffusion coefficient of BHT in PE are elevated. This study is helpful to the research of high-pressure food safety and packaging migration. [ABSTRACT FROM PUBLISHER]

Porphyrins typically show preferential uptake and retention by tumor tissues via receptor-mediated endocytosis of low-density lipoproteins. To investigate the relative importance of active and passive targeting strategies, the synthesis, characterization,in vitrouptake, andin vivobiodistribution of specific targeting porphyrin HPMA [HPMA:N-(2-hydroxypropyl)methacrylamide] copolymer tracer poly(HPMA)-porphyrin-DTPA-99mTc (DTPA: diethylenetriaminepentaacetic acid), nonspecific targeting HPMA copolymer tracer poly(HPMA)-DTPA-99mTc, and nontargeting tracer DTPA-99mTc are described in this study. The results showed that the cellular accumulation of poly(HPMA)-porphyrin-DTPA-99mTc complex was found to be time-dependent. The uptake of poly(HPMA)-porphyrin-DTPA-99mTc was significantly higher than that of poly(HPMA)-DTPA-99mTc, indicating that uptake of the poly(HPMA)-porphyrin-DTPA-99mTc was active binding. The uptake of poly(HPMA)-DTPA-99mTc was significantly higher than that of DTPA-99mTc, suggesting that uptake of the poly(HPMA)-DTPA-99mTc was passive binding. Twenty-four hour necropsy data in the hepatocellular carcinoma tumor model showed significantly higher (p < 0.001) tumor localization for poly(HPMA)-porphyrin-DTPA-99mTc (5.18 ± 0.50% ID/g [percentage injected dose per gram tissue]) compared with poly(HPMA)-DTPA-99mTc (2.69 ± 0.15% ID/g) and DTPA-99mTc (0.83 ± 0.03% ID/g). Moreover, higher T/B for poly(HPMA)-porphyrin-DTPA-99mTc indicated reduced extravasation of the targeted polymeric conjugates in normal tissues. Thus, the poly(HPMA)-porphyrin-DTPA-99mTc is a potential macromolecular tumor targeting molecular agent. [ABSTRACT FROM AUTHOR]

In the present study, magnetic iron-zirconium co-oxide microspheres were successfully synthesized by the emulsion and coprecipitation method in a single step. To obtain the ultimate material that possesses high zirconia content and suitable magnetic response, the ratios of the reactants were investigated systematically. The corresponding microspheres were characterized by scanning electron microscopy (SEM), X-ray fluorescence (XRF), powder X-ray diffraction, (XRD), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption/desorption measurements. The magnetic property of the particles was studied by a magnetic balance. The results demonstrated that the optimum ratio of zirconium precursor (zirconyl chloride) to iron precursor (ferric trichloride) was 3.0:5.0 g, in which microspheres with diameter of 2–5 µm, high surface area up to 62 m2/g, and suitable magnetic property were obtained. The magnetic iron-zirconium co-oxide microspheres are promising in various applications, including catalysis, bioseparation, drug carrier, etc. [ABSTRACT FROM PUBLISHER]

Constraining the origin of animal groups is allowed, to some extent, by discoveries of Cambrian Lagerstätten that preserve both mineralizing and nonmineralizing organisms. A new species is reported here of the Cambrian arthropod Skania , which bears an exoskeleton that shares homologies with the Neoproterozoic (Ediacaran) organism Parvancorina and firmly establishes a Precambrian root for arthropods. A new monophyletic group, Parvancorinomorpha, is proposed as the first clade within the arthropod crown group demonstrably ranging across the Neoproterozoic–Paleozoic transition. The Parvancorinomorpha is interpreted to be the sister group of the Arachnomorpha. Incipient cephalization in Skania and related genera represents a step in the progression toward division of a cephalon from a large posterior trunk as shown in Cambrian arachnomorphs such as naraoiids and the addition of a pygidium and thoracic tergites as shown in the arachnomorph clade basal to trilobites. This evidence can serve as a new calibration point for estimating the divergence time for the last common ancestor of arthropods and priapulids based on molecular clock methods. [ABSTRACT FROM AUTHOR]

In this article, propagation of a methane-air flame and its interaction with coal dust deposits have been investigated. The experiments were conducted in a horizontal flame acceleration tube with a square section. The photodiodes and digital video camera were employed to record the flame propagation. The results indicate that there are three distinguishable stages. In the first stage, gas flame accelerates gradually and deposited dust particles are ingested into air and heated by gas products until ignited at some point. In the second stage, a transient flame of three-front structure can be found, which consists of a leading gas flame, a forward dust flame, and a backward dust flame. In the last stage, the dust flame integrates into the gas flame, which forms a complex gas-dust flame that can continue to propagate. The results also show that the flame is accelerated slightly by the deposited dust but dramatically by obstacles under the present conditions. The terminal flame speed in the tube with the obstacle A of blockage ratio 0.05 or B of blockage ratio 0.10 is about 4 or 16 times as that without obstacles. [ABSTRACT FROM AUTHOR]

Investigates a dual beam single-staggered Millitron TWT microwave tubes made up of the Bonded Multiple Channel slow-wave system. Improvement of gain and bandwidth of the device by controlling the coupling between the chains of cavities; Dispersion characteristics and interaction impedance.