Balanced Shh signaling is required for proper formation and maintenance of dorsal telencephalic midline structures

<p>Abstract</p> <p>Background</p> <p>The rostral telencephalic dorsal midline is an organizing center critical for the formation of the future cortex and hippocampus. While the intersection of WNTs, BMPs, and FGFs establishes boundaries within this critical center, a direct role of Shh signaling in this region remains controversial. In this paper we show that both increased and decreased Shh signaling directly affects boundary formation within the telencephalic dorsal midline.</p> <p>Results</p> <p>Viral over-expression of Shh in the embryonic telencephalon prevents formation of the cortical hem and choroid plexus, while expanding the roof plate. In a transgenic model where cholesterol-lacking ShhN is expressed from one allele (<it>ShhN/+</it>), genes expressed in all three domains, cortical hem, choroid plexus and roof plate expand. In <it>Gli1/2 -/- </it>mutant brains, where Shh signaling is reduced, the roof plate expands, again at the expense of cortical hem and plexus. Cell autonomous activation of Shh signaling in the dorsal midline through Gdf7-driven activated Smoothened expression results in expansion of the <it>Wnt3a</it>-expressing cortical hem into the plexus domain. In addition, developmental stage determines dorsal midline responsiveness to Shh.</p> <p>Conclusions</p> <p>Together, these data demonstrate that balanced Shh signaling is critical for maintaining regional boundaries within the dorsal midline telencephalic organizing center.</p

A New Diverting Agent Material for Hydraulic Fracturing Treatment in Oil and Gas Industry

In-fissure divert fracturing technology, in which diverting agent is added. It can create new branch fractures and micro fractures, increase the area of fluid-release and achieve the goal of production and injection increase. This paper introduces a new diverting agent material with different kinds of petroleum resins. A series of evaluation including compatibility, efficiency and dissolved time was put forward. The results showed that the soluble rate of this agent is from 6 h to 12h and with increasing temperature and prolonging dissolved time, soluble rate reach 96% at 110° indicated good solubility. The critical flow velocity of sand production increases more than 30 ~ 60 times with adding fiber. The highest breakthrough pressure can reach 0.5MPa in 10 cm cores containing 9‰ diverting agent in the fracturing fluid. Meanwhile, it has minimal impact on flow conductivity .It had good flow back after treatment the viscosity was 13-54 mPa.s. Moreover, a special instrument was introduced to evaluate the performances of fracture conductivity and diverting. More than 24 treatments with this new material in X oil field have been performed with encouraging results with an average post-fracturing rate 11m3/d. It has great influences on new chemical material for improving complex fractures net-work of hydraulic fracturing in tight oil and gas reservoirs

A New Diverting Agent Material for Hydraulic Fracturing Treatment in Oil and Gas Industry

In-fissure divert fracturing technology, in which diverting agent is added. It can create new branch fractures and micro fractures, increase the area of fluid-release and achieve the goal of production and injection increase. This paper introduces a new diverting agent material with different kinds of petroleum resins. A series of evaluation including compatibility, efficiency and dissolved time was put forward. The results showed that the soluble rate of this agent is from 6 h to 12h and with increasing temperature and prolonging dissolved time, soluble rate reach 96% at 110° indicated good solubility. The critical flow velocity of sand production increases more than 30 ~ 60 times with adding fiber. The highest breakthrough pressure can reach 0.5MPa in 10 cm cores containing 9‰ diverting agent in the fracturing fluid. Meanwhile, it has minimal impact on flow conductivity .It had good flow back after treatment the viscosity was 13-54 mPa.s. Moreover, a special instrument was introduced to evaluate the performances of fracture conductivity and diverting. More than 24 treatments with this new material in X oil field have been performed with encouraging results with an average post-fracturing rate 11m3/d. It has great influences on new chemical material for improving complex fractures net-work of hydraulic fracturing in tight oil and gas reservoirs

The theory-of-mind network in support of action verb comprehension: Evidence from an fMRI study

The theory-of-mind (TOM) network refers to a specific group of brain regions implicated in the thinking of people&#39;s mental states. It remains unclear how this network contributes to verb comprehension. In the present study, we compared brain activations evoked by verbs that refer to social actions, private actions, and nonhuman events. All classic regions of the ToM network, including the posterior superior temporal sulcus (pSTS) whose activation during word comprehension is typically interpreted as the processing of motion properties, showed stronger activations to social action verbs than the others. These findings indicate that the ToM network is involved in the processing of social/mental knowledge of verb meanings. Furthermore, the activation of the pSTS during word comprehension mainly reflects the processing of social/mental properties but not that of biological-motion properties. (C) 2014 Elsevier Inc. All rights reserved

Compositional Changes during Hydrodeoxygenation of Biomass Pyrolysis Oil

Hydrodeoxygenation (HDO) is usually considered as a promising process for upgrading biomass pyrolysis oil (PO) to bio-fuels. However, cognition of HDO is inhibited by the complexity of the PO and upgraded products. In this study, a PO and its upgraded pyrolysis oil (UPO) samples were analyzed by nuclear magnetic resonance, gas chromatography/mass spectrometry, and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS). ESI FT-ICR MS revealed the most abundant compounds in PO were O₂–O₁₈ species with double bond equivalent (DBE) values of 0–22. After HDO, oxygen numbers gradually shifted to a range of O₁–O₁₀, and DBE number also progressively decreased. The major oxygen compounds such as carbonyls, carboxylic acids, ethers, carbohydrates, and alcohols were significantly changed with respect to relative content and molecular composition. Lignin polymers were depolymerized after reduction of the carbonyl and methoxy groups. For HDO, hydrogenation of carbonyls, carbohydrates, and furans occurred under 150 °C. Dehydration, hydrodeoxygenation, and dehydration–hydrogenation reactions were initiated at 210 °C. Decarboxylation and decarbonylation required higher temperatures (>300 °C)

Development of a Reference Standard of <i>Escherichia coli</i> DNA for Residual DNA Determination in China

<div><p>This collaborative study developed the first national <i>Escherichia coli</i> (<i>E. coli</i>) DNA reference standard for standardizing quantitative residual DNA assay methods, fluorescence dye (PicoGreen) and quantitative PCR (q-PCR), which were widely employed to measure residual DNA contents of prokaryotic-derived recombinant products. High purity of <i>E. coli</i> strain <i>BL21</i> was extracted by the cetyl triethyl ammonium bromide (CTAB)/phenol chloroform method, analyzed by UV-visible spectrophotometry and electrophoresis, diluted with tris-EDTA (TE) buffer and manually dispensed. Then, with a cooperative calibration among six laboratories, including five manufacturers and one national control laboratory, the concentration of <i>E. coli</i> DNA standard solution was determined as 96.2 μg/mL (95% C.I: 95.5–96.9 μg/mL, CV 3.4%). The candidate showed excellent stability both from accelerated degradation study and real time stability study. The applicability study showed that the <i>E. coli</i> DNA reference could reach the sensitivity of 0.781 ng/mL and 1 fg/μL, respectively, in fluorescent dye and q-PCR assay, and also had good linearity and precision. The consistency of the reference could meet the requirements of the national reference standard. As a conclusion, the candidate material was suitable to serve as a China national standard for <i>E. coli</i> residual DNA determination. The successful establishment of the <i>E. coli</i> DNA standard will facilitate the standardization of quantitative methods for testing residual host cell DNA.</p></div

Results of real-time PCR for <i>E. coli</i> DNA reference standard.

<p>(A) Standard curve. Ct was plotted against each concentration (Log Co). Ct represents the cycle at which reporter signal was first detected. (B) Amplification curves. 1–6: 10², 10, 1, 1×10⁻¹, 1×10⁻², 1×10⁻³ pg/μL. (C) Melting curves. It showed primer pair was specific for <i>E. coli</i> DNA.</p

Preparation and quality control of <i>E. coli</i> DNA reference standard.

<p>(A) Analysis of <i>E. coli</i> genomic DNA with full wavelength scanning (240–350 nm). (B) Results of Agarose Gel electrophoresis for <i>E. coli</i> genomic DNA. M, λ-Hind III digest DNA marker. Lane 1, <i>E. coli</i> genomic DNA.</p

The consistency analysis of <i>E. coli</i> DNA reference standard using PicoGreen fluorescence method.

<p>The consistency analysis of <i>E. coli</i> DNA reference standard using PicoGreen fluorescence method.</p

Stability of <i>E. coli</i> DNA reference standard.

<p>(A) The content and OD₂₆₀/OD₂₈₀ of <i>E. coli</i> DNA reference stored under four different temperatures for four months. (B) The electrophoresis of <i>E. coli</i> DNA reference stored under four different temperatures for four months. Because of high DNA content, some genomic DNA was stuck in the well. (C) The electrophoresis of <i>E. coli</i> DNA reference stored at −20°C for 24 months.</p