Suitable energy platform significantly improves charge separation of g-C_3N_4 for CO_2 reduction and pollutant oxidation under visible-light

The photocatalytic activities of g-C_3N_4 can be significantly improved by increasing life time of the photogenerated charges. Here, in this work we introduced TiO_2 as proper energy platform to accept the photogenerated electrons from g-C_3N_4 during photocatalysis. The nanophotocatalysts formed from the combination of a suitable amount of TiO_2 nanoparticles and g-C_3N_4 nanosheets showed 8.75 and 4.22% enhancement in photocatalytic activities for CO_2 reduction and 2-chlorophenol(2-CP) degradation under visible light illumination as compared to bare g-C_3N_4. Based on the surface photovoltage spectra, photoluminescence spectra and examination of formed hydroxyl radicals, it was confirmed that these enhanced photoactivities were attributed to the much-improved charge separation via the electron transfer from g-C_3N_4 to TiO_2. From trapping experiments,it was found that hydroxyl radicals were the major species involved in the photocatalytic degradation of 2-CP.This study is helpful to synthesize efficient photocatalysts to cope with energy and environmental issues.     

How atomic nuclei cluster

Nucleonic matter displays a quantum-liquid structure, but in some cases finite nuclei behave like molecules composed of clusters of protons and neutrons. Clustering is a recurrent feature in light nuclei, from beryllium to nickel. Cluster structures are typically observed as excited states close to the corresponding decay threshold; the origin of this phenomenon lies in the effective nuclear interaction, but the detailed mechanism of clustering in nuclei has not yet been fully understood. Here we use the theoretical framework of energy-density functionals, encompassing both cluster and quantum liquid-drop aspects of nuclei, to show that conditions for cluster formation can in part be traced back to the depth of the confining nuclear potential. For the illustrative example of neon-20, we show that the depth of the potential determines the energy spacings between single-nucleon orbitals in deformed nuclei, the localization of the corresponding wavefunctions and, therefore, the degree of nucleonic density clustering. Relativistic functionals, in particular, are characterized by deep single-nucleon potentials. When compared to non-relativistic functionals that yield similar ground-state properties (binding energy, deformation, radii), they predict the occurrence of much more pronounced cluster structures. More generally, clustering is considered as a transitional phenomenon between crystalline and quantum-liquid phases of fermionic systems.     

Differential positioning of adherens junctions is associated with initiation of epithelial folding

During tissue morphogenesis, simple epithelial sheets undergo folding to form complex structures. The prevailing model underlying epithelial folding involves cell shape changes driven by myosin-dependent apical constriction. Here we describe an alternative mechanism that requires differential positioning of adherens junctions controlled by modulation of epithelial apical-basal polarity. Using live embryo imaging, we show that before the initiation of dorsal transverse folds during Drosophila gastrulation, adherens junctions shift basally in the initiating cells, but maintain their original subapical positioning in the neighbouring cells. Junctional positioning in the dorsal epithelium depends on the polarity proteins Bazooka and Par-1. In particular, the basal shift that occurs in the initiating cells is associated with a progressive decrease in Par-1 levels. We show that uniform reduction of the activity of Bazooka or Par-1 results in uniform apical or lateral positioning of junctions and in each case dorsal fold initiation is abolished. In addition, an increase in the Bazooka/Par-1 ratio causes formation of ectopic dorsal folds. The basal shift of junctions not only alters the apical shape of the initiating cells, but also forces the lateral membrane of the adjacent cells to bend towards the initiating cells, thereby facilitating tissue deformation. Our data thus establish a direct link between modification of epithelial polarity and initiation of epithelial folding.     

First record of the genus Paragigagnathus Amitai and Grinberg, 1971 (Mesostigmata: Phytoseiidae) from Saudi Arabia with description of a new species

The genus Paragigagnathus Amitai and Grinberg (Acari: Phytoseiidae) is reported for the first time from Saudi Arabia. Paragigagnathus desertorum (Amitai and Swirski) and P. insuetus (Livshitz and Kuznetsov) were collected from Acacia sp. (Fabaceae) and Tamarix sp. (Tamaricaceae), respectively. Paragigagnathus madinaensis n. sp. is described and illustrated. The new species was found on Tamarix sp. in association with Obdulia daadi Al-Gboory (Prostigmata: Tenuipalpidae) from Al-Riyadh and Al-Madina regions of Saudi Arabia.     

Application of Quality of Experience in Networked Services: Review,Trend & Perspectives

Over the last decade, there has been an exponential growth of services over the Internet. Services such as online gaming are gaining popularity, whereas, Voice over Internet (VoIP) has been well established. Storage, management and processing of data have moved away from the devices to the cloud. Quality of experience (QoE) defined as the user’s perception of service quality is utilized in different technologies, services and products for improving end user satisfaction and provides quality of service (QoS) according to their demands. In this paper, we describe the utilization of QoE in different technologies, services and products for improving end user satisfaction. Specifically, we present the latest developments in QoE in multimedia services, network management, VoIP, web development, games and cloud computing. Finally, we discuss the current research, solutions and present open issues of future research in QoE.

     

Mutations in NALP7 cause recurrent hydatidiform moles and reproductive wastage in humans

Hydatidiform mole (HM) is an abnormal human pregnancy with no embryo and cystic degeneration of placental villi. We report five mutations in the maternal gene NALP7 in individuals with familial and recurrent HMs. NALP7 is a member of the CATERPILLER protein family involved in inflammation and apoptosis. NALP7 is the first maternal effect gene identified in humans and is also responsible for recurrent spontaneous abortions, stillbirths and intrauterine growth retardation.     

肉毒毒素A对大鼠慢性神经源性疼痛镇痛作用的研究

目的观察肉毒毒素A(BoNT-A)对L5、L6脊神经结扎引起慢性神经源性疼痛模型大鼠行为学的影响。方法建立Wistar大鼠左侧L5、L6脊神经结扎模型(SNL模型)。SNL模型大鼠随机分为3组(n=8)。1)实验组:SNL术后第3天同侧足底皮下注射BoNT-A30U/kg;2)对照组:SNL术后同侧足底皮下注射相同容积生理盐水;3)假手术组:仅暴露而不结扎L5和L6脊神经。均分别测定术前、给药前、给药后1d、3d、5d、7d、14d、21d的机械缩足反射阈值(MWT)和热缩足反射潜伏期(TWL)。结果实验组手术同侧足底皮下注射BoNT-A可以增加大鼠的MWT和TWL,实验组手术对侧、对照组、假手术组应用BoNT-A对MWT和TWL无影响。结论足底皮下注射BoNTA能够改善SNL模型大鼠手术同侧肢体的MWT和TWL,有镇痛作用。     

Factors influencing the distribution of 99m-technetium methylene diphosphonate in bone and soft tissues.

The influences of dilution, storage and pH on the distribution of 99m-technetium methylene diphosphonate (99m-Tc-MDP) in bone and various soft tissues have been investigated in the rat. The results show a marked departure from normality when large dilution factors and very acidic or basic preparations are used.     

Effect of salinity on seed germination of Triglochin maritima under various temperature regimes

Triglochin maritima L. (arrow grass), an herbaceous perennial in the family Juncaginacea, is widely distributed in inland and coastal salt marshes of North America. Triglochin maritima seeds from a population growing in a salt marsh at Faust, Utah, were germinated at 4 temperature regimes (12-h night/12-h day, 5-15° C, 10-20° C, and 15-25° C) and 5 salinities (0, 100, 200, 300, 400, and 500 mol m -3 NaCl) to determine optimal conditions for germination and level of salt tolerance. Ungerminated seeds were returned to distilled water after 20 d to determine whether seeds could recover from salinity treatments. Maximum germination occurred in distilled water, and increases in NaCl concentration progressively inhibited seed germination. No seeds germinated at concentrations higher than 400 mol m -3 NaCl. A temperature regime of low night (5° C) and high day (25° C) temperature yielded maximum germination; all other temperature regimes significantly inhibited seed germination relative to this optimum. Recovery of germination was highest at 5-25° C and lowest at 5-15° C. Recovery of seed germination when seeds were transferred to distilled water from salt solutions was highest at 5-25° C (72%) for seeds exposed to the 500 mol m -3 NaCl pretreatment and significantly reduced at other temperature regimes. The recovery germination response indicates a synergistic inhibitory interaction effect on germination when seeds were exposed to high salinities at suboptimal thermoperiods.