Recent efforts to evaluate the contribution of neonicotinoid insecticides to worldwide pollinator declines have focused on honey bees and the chronic levels of exposure experienced when foraging on ...crops grown from neonicotinoid-treated seeds. However, few studies address non-crop plants as a potential route of pollinator exposure to neonicotinoid and other insecticides. Here we show that pollen collected by honey bee foragers in maize- and soybean-dominated landscapes is contaminated throughout the growing season with multiple agricultural pesticides, including the neonicotinoids used as seed treatments. Notably, however, the highest levels of contamination in pollen are pyrethroid insecticides targeting mosquitoes and other nuisance pests. Furthermore, pollen from crop plants represents only a tiny fraction of the total diversity of pollen resources used by honey bees in these landscapes, with the principle sources of pollen originating from non-cultivated plants. These findings provide fundamental information about the foraging habits of honey bees in these landscapes.
Porous gelatin scaffolds with microtubule orientation structure were manufactured by unidirectional freeze-drying technology, and their porous structure was characterized by scanning electron ...microscopy. Scaffolds with tunable pore size and high porosity up to 98% were obtained by adjusting the concentration of the gelatin solution and crosslinking agent during the preparation process. All the porous gelatin scaffolds exhibited oriented microtubule pores, with width and length from 50 to 100
μm and 100 to 500
μm, respectively. Meanwhile, the properties of the scaffolds, such as porosity, water adsorption ability and compressive strength, were studied. In vitro enzymatic degradation results showed that the absolute weight loss of the gelatin scaffolds exhibited an increasing trend from low to high gelatin concentration used to prepare gelatin scaffolds; in vitro cell culture results indicated that the porous gelatin scaffolds were non-toxic to cartilage cells, since the cells spread and grew well.
The mechanism of superconductivity in cuprates remains one of the big challenges of condensed matter physics. High-Tc
cuprates crystallize into a layered perovskite structure featuring copper oxygen ...octahedral coordination. Due to the Jahn Teller effect in combination with the strong static Coulomb interaction, the octahedra in high-Tc
cuprates are elongated along the c axis, leading to a 3dx²-y² orbital at the top of the band structure wherein the doped holes reside. This scenario gives rise to 2D characteristics in high-Tc
cuprates that favor d-wave pairing symmetry. Here, we report superconductivity in a cuprate Ba₂CuO4-y, wherein the local octahedron is in a very exceptional compressed version. The Ba₂CuO4-y compound was synthesized at high pressure at high temperatures and shows bulk superconductivity with critical temperature (Tc
) above 70 K at ambient conditions. This superconducting transition temperature is more than 30 K higher than the Tc
for the isostructural counterparts based on classical La₂CuO₄. X-ray absorption measurements indicate the heavily doped nature of the Ba₂CuO4-y superconductor. In compressed octahedron, the 3d3z²-r² orbital will be lifted above the 3dx²-y² orbital, leading to significant 3D nature in addition to the conventional 3dx²-y² orbital. This work sheds important light on advancing our comprehensive understanding of the superconducting mechanism of high Tc
in cuprate materials.
Compared with other nanofiber fabrication processes, electrospinning is versatile and superior in production and construction of ordered or more complex nanofibrous assemblies. Besides traditional ...two-dimensional (2D) nanofibrous structures, electrospinning is powerful in fabrication of three-dimensional (3D) fibrous macrostructures, especially for tissue engineering applications. This article summarizes and reviews recent advances in various promising and cutting-edge electrospinning techniques, including multilayering electrospinning, post-processing after electrospinning, liquid-assisted collection, template-assisted collection, porogen-added electrospinning, and self-assembly. And their formation mechanisms, features, and the challenges of electrospinning have also been discussed. Furthermore, these 3D nanofibrous macrostructures have been demonstrated to have potential applications in tissue engineering, energy harvesting and storage, and filtration.
AIMS: To investigate the effects of an egg yolk‐derived immunoglobulin (IgY) specific to Prevotella intermedia in vitro and in vivo. METHODS AND RESULTS: An IgY specific to P. intermedia was produced ...by immunizing hens with formaldehyde‐inactivated P. intermedia and showed high titres when subjected to an ELISA. The obtained IgY inhibited the growth of P. intermedia in a dose‐dependent manner at concentrations from 1 to 20 mg ml⁻¹in Center for Disease Control and Prevention liquid medium. Forty rats were challenged with P. intermedia on gingivae and then randomly divided into four groups, which were syringed respectively with phosphate‐buffered saline, 1 mg ml⁻¹of tinidazole, 20 mg ml⁻¹of nonspecific IgY and 20 mg ml⁻¹of the IgY specific to P. intermedia at a dosage of 300 μl per day. Gingival index (GI), plaque index (PI), bleeding on probing (BOP), counts of white blood cell (WBC) and histopathological slide of the gums were measured after treatment for 15 days. The gingivitis rats treated with the IgY specific to P. intermedia showed significantly decreased GI, PI, BOP and WBC (P < 0·05). Gum histopathology of the treated rats demonstrated a superior protective effect of the specific IgY on P. intermedia‐mediated gingivitis. CONCLUSIONS: A new immunoglobulin specific to P. intermedia was developed from egg yolk. This specific IgY can dose‐dependently inhibit the growth of P. intermedia and protect rats from gingivitis induced by P. intermedia. SIGNIFICANCE AND IMPACT OF THE STUDY: The new IgY has potential for the treatment of P. intermedia‐mediated gingivitis.
Abstract
Recently, theoretical studies show that layered HfTe
5
is at the boundary of weak & strong topological insulator (TI) and might crossover to a Dirac semimetal state by changing lattice ...parameters. The topological properties of 3D stacked HfTe
5
are expected hence to be sensitive to pressures tuning. Here, we report pressure induced phase evolution in both electronic & crystal structures for HfTe
5
with a culmination of pressure induced superconductivity. Our experiments indicated that the temperature for anomaly resistance peak (Tp) due to Lifshitz transition decreases first before climbs up to a maximum with pressure while the Tp minimum corresponds to the transition from a weak TI to strong TI. The HfTe
5
crystal becomes superconductive above ~5.5 GPa where the Tp reaches maximum. The highest superconducting transition temperature (Tc) around 5 K was achieved at 20 GPa. Crystal structure studies indicate that HfTe
5
transforms from a Cmcm phase across a monoclinic C2/m phase then to a P-1 phase with increasing pressure. Based on transport, structure studies a comprehensive phase diagram of HfTe
5
is constructed as function of pressure. The work provides valuable experimental insights into the evolution on how to proceed from a weak TI precursor across a strong TI to superconductors.
Background and purpose
The aim was to describe the clinical, radiological and pathological features of an autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy.
Methods
Data from 19 ...patients with positive GFAP‐immunoglobulin G in cerebrospinal fluid (CSF) were retrospectively analyzed.
Results
The main disease manifestations included myelitis (68.4%), headache (63.2%), abnormal vision (63.2%), fever (52.6%), ataxia (36.8%), psychosis (31.6%), dyskinesia (15.8%), dementia (15.8%) and seizure (10.5%). Seventeen patients had brain abnormalities (89.5%), of which eight (42.1%) revealed the characteristic radial enhancing and laminar patterns. Cortical abnormalities were found in four patients (21.1%). Other abnormalities were found in the hypothalamus, midbrain, pons, medulla cerebellum, meninges and skull. Eleven patients had longitudinally extensive spinal cord lesions. CSF abnormalities were detected in all patients. Pathological examinations of four patients revealed extensive inflammation, with prominent perivascular B cells and T cells. Abundant antibody‐secreting cells were noted in the interstitial and perivascular spaces. Immunohistochemical analysis showed loss of astrocytes and neurons.
Conclusion
The present patients with positive GFAP‐immunoglobulin G are highly similar to autoimmune GFAP astrocytopathy, described in a recent report. The features of the neuropathology and immunopathology of GFAP astrocytopathies were perivascular inflammation and loss of astrocytes and neurons.
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Desulfovibrio spp. is predominant member of sulphate‐reducing bacteria in human gut microbiota. Previous studies indicated that the isolation of Desulfovibrio strains from human faecal samples is ...very important to study the roles of human intestinal Desulfovibrio spp. in maintaining healthy states or causing diseases, as well as defining their biological characteristics. However, there are very few reports describing the isolation of Desulfovibrio spp. from human faecal samples. In this study, faecal samples were inoculated into various media containing different components. The enriched culture communities were identified using 16S rRNA gene high‐throughput sequencing analysis, enabling us to identify the specific components that enable the enrichment of Desulfovibrio. Using this information, we developed five specific media and identified an effective enrichment medium that produced the highest relative abundance of Desulfovibrio in communities cultured from four faecal samples (26·5, 73·5, 44·7 and 77·6% respectively). In addition, the major non‐Desulfovibrio genera were identified. Finally, three species of Desulfovibrio, D. desulfuricans, D. piger and D. legallii were isolated, representing the first time that has D. legallii been isolated from a human gastrointestinal source.
Significance and Impact of the Study
ost of the human intestinal bacteria have not been cultured because of lack of appropriate culture method and appropriate media. Desulfovibrio spp. is associated with several clinical conditions like inflammatory bowel disease, but until now there are very few reports describing the isolation of Desulfovibrio spp. from human faecal samples. In this study, 16S rRNA gene high‐throughput sequencing analysis was applied to screen appropriate enrichment media and selective cultivation of Desulfovibrio. This sequencing‐based directed culture method described here can be used for the selective cultivation of gut bacteria of interest.
Significance and Impact of the Study: Most of the human intestinal bacteria have not been cultured because of lack of appropriate culture method and appropriate media. Desulfovibrio spp. is associated with several clinical conditions like inflammatory bowel disease, but until now there are very few reports describing the isolation of Desulfovibrio spp. from human faecal samples. In this study, 16S rRNA gene high‐throughput sequencing analysis was applied to screen appropriate enrichment media and selective cultivation of Desulfovibrio. This sequencing‐based directed culture method described here can be used for the selective cultivation of gut bacteria of interest.
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