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The sandstone composition analysis carried out on the samples from three different sections (western section, middle section and eastern section) of the Upper Jurassic Emuerhe Formation in the Mohe Basin, northeastern China, reveals that the Okhotsk orogenic belt and the Ergun massif basement are the source areas for the Emuerhe Formation. The source area of the western section and the A segment of the middle section is the Okhotsk orogenic belt. The tectonic attributes of the Okhotsk orogenic belt are those of a dissected arc. The transportation distance of clastic rocks from these sections gradually lengthened, and the uplift rate of the Okhotsk orogenic belt gradually increased. The source area of the eastern section and the B segment of the middle section is the Ergun massif basement. Compared with the Okhotsk orogenic belt, the tectonic attributes and uplift rate of the Ergun massif basement are different from the former. The attributes of the Ergun massif basement are those of basement uplift. The transportation distance of clastic rocks from the eastern section and the B segment of the middle section gradually shortened, and the uplift rate of the Ergun massif basement gradually decreased. These conclusions are consistent with the characteristics of a foreland basin. Thus, we can draw the conclusion that the Mohe Basin belongs to the foreland basin. [ABSTRACT FROM AUTHOR]

Aim: p16 Methylation frequently occurs in carcinogenesis. While it has been hypothesized that the p16 methylation states are dynamically maintained in cancer cells, direct evidence supporting this hypothesis has not been available until now. Methods: A fusion cell model was established which reprogrammed the native DNA methylation pattern of the cells. The methylation status of the p16 alleles was then repeatedly quantitatively analyzed in the fusion monoclonal, parental cancer cell lines (p16-completely methylated-AGS and unmethylated-MGC803), and HCT116 non-fusion cell using DHPLC and bisulfite sequencing. Histone methylation was analyzed using chromatin immuno-precipitation (ChIP)-PCR. P16 expression status was determined using immuno-staining and RT-PCR. Results: The methylation status for the majority of the p16 alleles was stably maintained in the fusion monoclonal cells after up to 60 passages. Most importantly, focal de novo methylation, demethylation, and hydroxymethylation were consistently observed within about 27% of the p16 alleles in the fusion monoclones, but not the homozygously methylated or unmethylated parental cells. Furthermore, subclones of the monoclones consistently maintained the same p16 methylation pattern. A similar phenomenon was also observed using the p16 hemi-methylated HCT116 non-fusion cancer cell line. Interestingly, transcription was not observed in p16 alleles that were hydroxymethylated with an antisense-strand-specific pattern. Also, the levels of H3K9 and H3K4 trimethylation in the fusion cells were found to be slightly lower than the parental AGS and MGC803 cells, respectively. Conclusion: The present study provides the first direct evidence confirming that the methylation states of p16 CpG islands is not only homeostatically maintained, but also accompanied by a dynamic process of transient focal methylation, demethylation, and hydroxymethylation in cancer cells. [ABSTRACT FROM AUTHOR]

This paper demonstrates the fabrication of self-aligned gate-last enhancement- and depletion-mode (E/D-mode) AlN/GaN metal-oxide-semiconductor high-electron-mobility-transistors (MOSHEMTs). In addition, the effects of annealing on threshold voltage ( Vth) are analyzed. The E and D-mode transistors were fabricated with Ni/Au and Ti/Au as the gate metal, respectively. The Ni/Au gated MOSHEMTs show Vth = +0.3 V after post-gate metallization annealing, and the Ti/Au gated MOSHEMTs without annealing show Vth= -1.8 V. In the E-mode (Ni/Au gated) transistors, the Vth shift after post-gate annealing is due to the decrease of fixed charges at the Al2O3/GaN interface. An investigation has been conducted for the understanding of the Vth shift, which is crucial for improving the transistors' stability in various applications. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

2 nanofibers and nanotubes were synthesized by electrospinning method. Magnetization measurement indicates that the 2 nanofibers and nanotubes annealed in air at 500°C exhibit the room-temperature ferromagnetism and the ferromagnetism of nanotubes is stronger than the nanofibers. Selected area electron diffraction, X-ray diffraction and Raman measurements show that all the samples possess a typical rutile structure and no other impurity phases are observed. The results of the Raman spectra also indicate that there are lots of defects existing in the fabricated samples. The observed room-temperature ferromagnetism in 2 nanofibers and nanotubes possibly originates from oxygen vacancies. The field cooled (FC) and zero-field-cooled (ZFC) magnetization curves indicate that the Curie temperature TC is above 300 K. SnO2 nanofibers and nanotubes were synthesized the electrospinning method. The observed room-temperature ferromagnetism originates from surface defects. [ABSTRACT FROM AUTHOR]

A diode-pumped passively Q-switched Nd:YAG/KLu(WO) (KLW) Raman laser is presented for the first time. As high as 1.89 W average output power is obtained at the pump power of 15.7 W with the pulse repetition frequency (PRF) of 27.2 kHz, and the corresponding diode-to-Stokes conversion efficiency is 12.0%. The highest pulse energy of 84.0 μJ is obtained. The obtained average output power and pulse energy are much higher than the previously reported results of diode-pumped passively Q-switched Raman lasers. [ABSTRACT FROM AUTHOR]

Taking Yilan Basin which is a typical Cenozoic fault basin for example, the occurrence and forming conditions were studied on shale, oil shale and coal based on field section profiles and comprehensive analysis indoors. Furthermore, the genesis and metallogenic regularities of coal and oil shale were showed by studying on paleoclimte, paleoenvironment and paleotectonic conditions. Coal-bearing beds of coal co-occurring with oil shale easily formed during episodic movement of tectonic subsidence at the beginning of the basin evolution. Coal deposited in shallow lacustrine basin of the fan front, and oil shale directly deposited on the coal interval, while oil shale stable sedimentary time during lake-basin expansion. Coal formed in lake marsh, while oil shale deposited in lake marsh and lacustrine. Coal and oil shale distributions were controlled by the basin-controlling fault of Yilan Basin, and became thicker near the F1 fault. That shows gradually onlapping from the lake level with the increasing depositing range of the lake basin. Coal mainly formed at warm and damp conditions, while the climate of oil shale formation generally tended to mild and a temperature decrease based on spore and pollen analysis. It was the subtropical climate, warm and damp, and the wind was weak at the lake level when the lake of Dalianhe Formation was developing. And that climate favored the formation of deep to semi-deep lake environment which was reducing and stable and easily made for oil shale. The achievements above will shape some theoretical foundations for exploring energy basins which are rich in resources of oil and gas, shale gas and coal-bed gas. [ABSTRACT FROM AUTHOR]

This study describes an alternative arteriovenous fistula (AVF) model in the rat in which the animals develop significant neointimal hyperplasia (NIH) not only at the distal anastomotic site, but also throughout the fistula body. This aortocaval fistula was established by anastomosing the distal end of the renal vein to the abdominal aorta after unilateral nephrectomy. The increased hemodynamic stress resulting from exposing the renal vein to the arterial circulation induced venous NIH as early as 7 days after surgery. This experimental AVF was characterized by the early lack of endothelium, the accumulation of proliferating vascular smooth muscle cells and the neovascularization of the fistula adventitia. In summary, we have described an informative animal model to study the pathobiology of NIH in native AVF. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Clay mineral and inorganic geochemical characteristics of Eocene Huadian formation in Huadian basin have been found through X-ray diffraction, scanning electron microscopy and inorganic geochemical element tests. Clay minerals of Huadian formation of the study area contain montmorillonite, kaolinite and illite. The content of montmorillonite is the highest, and illite/smectite mixed layer is rare. Mn, Sr, P, Cd, Sr/Cu, B/Ga, Sr/Ba and Ca/(Ca+Fe) change with an exactly similar trend vertically, and Cu, Cs, Rb/Sr, V/(V+Ni) and 8Ce change with another similar trend. Clay minerals and inorganic geochemical evidence reveal the characteristics of paleoclimate and paleolimnology:the upper section containing coal and the lower section containing pyrite of Huadian formation belong to terrestrial sedimentary environment under the condition of warm and humid climate and low salinity ; the middle section containing oil shale belongs to frequently alternating freshwater and saltwater environment, alternating humid and drought climate. The largest expansion phase of lacustrine basin which was under reduction condition with alternating humid and drought climate and salinity stratification developed semi-deep lake and deep lake facies which formed oil shale; the shrinkage phase of lacustrine basin with warm and humid climate developed delta plain with peat swamp which formed coal. [ABSTRACT FROM AUTHOR]

Objective: Matrix metalloproteinase-2 (MMP-2) degrades type IV collagen and enables endothelial cell (EC) migration during angiogenesis and wound healing. Peroxisomal biogenesis factor 2 (PEX2), a by-product of activated MMP-2 autocatalysis, competitively inhibits newly activated MMP-2 from EC surface binding and migration. We hypothesize that PEX2 is elevated during limb ischemia and contributes to poor wound healing, with decreased capillary density. Methods: Western blot was used to identify PEX2 in the hind limbs of FVB/NJ mice with surgically induced ischemia. The PEX2 effect on healing was evaluated by calculating the area of exposed muscle after wounding the dorsum of mice and administering daily injections with human recombinant PEX2 (hrPEX2). Wounds were also injected with lentivirus-expressing PEX2 (PEX2-LV), harvested on postoperative day 7 and processed for staining. Epithelial gap was assessed with light microscopy. Capillary density was evaluated after wounding Tie2-green fluorescent protein (GFP)+ transgenic FVB mice (ECs labeled green) and viral transduction with PEX2-LV. Wounds were harvested on postoperative day (POD) 7, frozen in liquid nitrogen, sectioned, and stained with Hoechst. Vessel density was assessed via fluorescence microscopy as the average number of capillaries/10 high-powered fields. Paired t test was used to assess differences between the groups. Results: PEX2 was elevated 5.5 ± 2.0-fold (P = .005) on POD 2 and 2.9 ± 0.69-fold (P = .004) on POD 4 in gastrocnemius muscles of ischemic hind limbs. The wound surface area, or lack of granulation tissue and exposed muscle, decreased daily in all mice but was greater in the hrPEX2-treated mice by 12% to 16% (P < .004). Wounds in the control group were completely covered with granulation tissue by POD 3. Wounds injected with hrPEX2 were not completely covered by POD 7 but continued to have exposed muscle. Microscopic examination of wounds after PEX2-LV viral transduction demonstrated an average epithelial gap of 1.6 ± 0.3 vs 0.64 ± 0.3 μm in control wounds (P < .04). Wounds from Tie2-GFP mice had an average number of 3.8 ± 1.1 capillaries vs 6.9 ± 1.2 in control wounds (P < .007). Conclusions: Our study links elevated PEX2 to ischemia and poor wound healing. We demonstrate comparative PEX2 elevation in ischemic murine hind limbs. Less granulation tissue is produced and healing is retarded in wounds subjected to hrPEX2 or viral transduction with PEX2-LV. Microscopic examination shows the wounds exhibit fewer capillaries, supporting the hypothesis that PEX2 decreases angiogenesis. [ABSTRACT FROM AUTHOR]

To elucidate the source of neointimal cells, experimental fistulas were created in Lewis wild-type (WT) and transgenic rats that constitutively expressed the green fluorescent protein (GFP) in all tissues. Arteriovenous fistula (AVFs) were created by anastomosing the left renal vein to the abdominal aorta. The contribution of bone marrow (BM)-derived cells to the AVF neointima was examined in lethally irradiated WT rats that had been rescued with GFP BM cells. Neointimal cells in these chimeric rats were mostly GFP negative indicating the non-BM origin of those cells. Then, the contribution of arterial cells to the AVF neointima was assessed in a fistula made with a GFP aorta that had been implanted orthotopically into a WT rat. Most of the neointimal cells were also GFP negative demonstrating that AVF neointimal cells are not derived from the feeding artery. Finally to study local resident cells contribution to the formation of neointimal lesions, a composite fistula was created by interposing a GFP vein between the renal vein and the aorta in a WT recipient rat. GFP neointimal cells were only found in the transplanted vein. This study suggests that neointimal cells originate from the local resident cells in the venous limb of the fistula. [ABSTRACT FROM AUTHOR]

Diabetes mellitus is a common disease afflicting many people. In addition to coronary artery disease, diabetic retinopathy and renal failure, diabetic patients face abnormal wound healing and have increased lower extremity ulcers and amputations. In diabetes, wound healing is altered due to both macrovascular and microvascular processes. While the former can be addressed with surgical intervention, the latter is more difficult to correct. Neovascularization within the granulation tissue via angiogenesis and vasculogenesis is critical for wound healing. Endothelial progenitor cells (EPCs) have been implicated in vasculogenesis. Mobilization of EPCs from the bone marrow is impaired in diabetes and homing of EPCs to the wound is also abnormal. Recent studies show that hyperoxia and administration of exogenous stromal-derived factor-1α increases circulatory and wound levels of EPCs and improves wound healing in diabetic mice. These findings have great potential for translation into human counterparts as the treatment for this prevalent disease matures. INSET: Key issues. [ABSTRACT FROM AUTHOR]

A theoretical model is developed for the laser-diode-pumped Tm3+-doped fiber amplifier, and a set of ordinary differential equations (ODEs) governing the dynamics of dual-wavelength pumping scheme (1.4μ+1.56μ) based on the rate equations and propagation equations was established. The relationship between the spectra gain and pump power was described and analyzed by numerically solving the ODEs. Spectral gain as a function of longitudinal position along the fiber was given to optimize the fiber length; spectral gain per unit length, and fractional inversion were used to explain the gain shift property of TDFA. The theoretical results agree well with the experimental data. [ABSTRACT FROM AUTHOR]