Although gully development is frequently observed to be associated with piping and tunnel erosion in many parts of the world, there is a lack of detailed studies on their spatial interactions. Such ...studies not only contribute to developing geomorphic theories on the evolution of both hillslopes and drainage networks but also are useful to design effective control measures of erosion. The present study aims to examine the interactions between gully development and tunnel erosion in the hilly Loess Plateau region of northern China. Firstly, gullies, tunnel inlets and mass movements in the 9.1km2 Wangjiagou watershed were mapped through aerial photo interpretation and reconnaissance surveys. Secondly, detailed field studies were carried out to investigate the interactions between gully development and tunnel formation processes in the selected gullies. Thirdly, the physiographic variables of gullies, derived from GIS and field measurements, were analyzed to identify differences between tunneled and untunneled gullies.
A total of 704 channels, 967 tunnel inlets and 547 mass movements were identified in the study watershed. On the basis of their location and morphology, all the channels were classified into four types: headwater gullies, hillside gullies, valleyside gullies and ephemeral river channels. Tunnels are associated with 79% of headwater gullies, 48% of hillside gullies, 3% of valleyside gullies and none of ephemeral river channels. Mass movements are dominated by falls in headwater gullies, falls and slides in hillside gullies, and soil creeps in ephemeral stream channels. Statistical tests indicate that there are significant differences in physiographic variables between tunneled and untunneled gullies. Tunnel formation in gullies is intricately affected by topographic conditions, land uses, knickpoint distribution, soil materials and mass movements.
► Distribution of gullies, tunnels, and mass movement in a semi-arid watershed. ► Tunnel erosion is active in the development of headwater and hillslope gullies. ► Tunnel erosion is largely absent in hanging gullies and ephemeral river channels. ► The frequency and types of mass movements vary according to types of gullies.
We report the experimental generation of highly energetic carbon ions up to 48 MeV per nucleon by shooting double-layer targets composed of well-controlled slightly underdense plasma and ultrathin ...foils with ultraintense femtosecond laser pulses. Particle-in-cell simulations reveal that carbon ions are ejected from the ultrathin foils due to radiation pressure and then accelerated in an enhanced sheath field established by the superponderomotive electron flow. Such a cascaded acceleration is especially suited for heavy ion acceleration with femtosecond laser pulses. The breakthrough of heavy ion energy up to many tens of MeV/u at a high repetition rate would be able to trigger significant advances in nuclear physics, high energy density physics, and medical physics.
Side population (SP) cells and their relationship to stem cell-like properties have been insufficiently studied in colorectal cancer (CRC). MicroRNAs (miRNAs) have attracted much attention but their ...roles in the maintenance of SP phenotype remain unclear.
The SPs from CRC cell lines and primary cell cultures were analysed for stem cell-like properties. MiRNA microarray analysis identified miR-328 as a potential stemness miRNA of SP phenotype. The level of miR-328 expression in clinical samples and its correlation with SP fraction were determined. Gain-of-function and loss-of-function studies were performed to examine its roles in cancer stem-like SP cells. Furthermore, bioinformatics prediction and experimental validation were used to identify miR-328 target genes.
The SP cells sorted from CRC possess cancer stem cell (CSC)-like properties, including self-renewal, differentiation, resistance to chemotherapy, invasive and strong tumour formation ability. MiR-328 expression was significantly reduced in SP cells compared with Non-SP cells (P<0.05). Moreover, miR-328 expression was downregulated in CRC (n=33, P<0.05) and low miR-328 expression tend to correlate with high SP fraction (n=15, r=0.6559, P<0.05, Pearson's correlation). Functional studies indicated that miR-328 expression affects the number of SP cells. In addition, miR-328 overexpression reversed drug resistance and inhibited cell invasion of SP cells. Furthermore, luciferase reporter assay demonstrated that miR-328 directly targets ABCG2 and MMP16 and affects the levels of mRNA and protein expression in SP cells.
These findings indicate that CRC contain cancer stem-like SP cells. MiR-328 has an important role in maintaining cancer stem-like SP phenotype that may be a potential target for effective CRC therapy.
In Alzheimer's disease (AD), neurodegenerative signals such as amyloid-beta (Aβ) and the precursors of neurotrophins, outbalance neurotrophic signals, causing synaptic dysfunction and ...neurodegeneration. The neurotrophin receptor p75 (p75NTR) is a receptor of Aβ and mediates Aβ-induced neurodegenerative signals. The shedding of its ectodomain from the cell surface is physiologically regulated; however, the function of the diffusible p75NTR ectodomain (p75ECD) after shedding remains largely not known. Here, we show that p75ECD levels in cerebrospinal fluid and in the brains of Alzheimer's patients and amyloid-beta precursor protein (APP)/PS1 transgenic mice were significantly reduced, due to inhibition of the sheddase-tumor necrosis factor-alpha-converting enzyme by Aβ. Restoration of p75ECD to the normal level by brain delivery of the gene encoding human p75ECD before or after Aβ deposition in the brain of APP/PS1 mice reversed the behavioral deficits and AD-type pathologies, such as Aβ deposit, apoptotic events, neuroinflammation, Tau phosphorylation and loss of dendritic spine, neuronal structures and synaptic proteins. Furthermore, p75ECD can also reduce amyloidogenesis by suppressing β-secretase expression and activities. Our data demonstrate that p75ECD is a physiologically neuroprotective molecule against Aβ toxicity and would be a novel therapeutic target and biomarker for AD.
Two experiments were conducted to determine the effects of Lactobacillus plantarum B1 on broiler performance, cecal bacteria, and ileal and cecal short chain fatty acids (SCFA). The study also ...determined whether it was necessary to feed Lactobacillus throughout the entire growth period or if the beneficial effects could be obtained by supplementation during the starter or finisher period only. Experiment 1 was conducted with 72 broilers assigned to 2 treatments (N = 6). One treatment was the basal diet (Con), and the other was the basal diet supplemented with 2 × 109 cfu/kg L. plantarum B1 (Wh). In experiment 2, 144 one-day-old broilers were assigned to 4 treatments (N = 6) including a basal diet (Con), the basal diet supplemented with 2 × 109 cfu/kg L. plantarum B1 during d one to 21 only (St), the basal diet supplemented with L. plantarum B1 during d 22 to 42 only (Fn), and, finally, the basal diet supplemented with L. plantarum B1 from d one to 42 (Wh). Experiment 1 showed that L. plantarum B1 enhanced broiler average daily gain (ADG) and feed conversion ratio (FCR). In experiment 2, during the starter period, broilers in the Wh and St treatments had higher ADG (P < 0.05) than broilers in the Con and Fn, while during the finisher period, broilers in the Wh and Fn had higher ADG (P < 0.01) and improved FCR (P < 0.01) compared with broilers in the Con and St. On d 42, broilers in the Wh and Fn had decreased E. coli (P < 0.05) and increased lactic acid bacteria (P < 0.05) in their cecal digesta. L. plantarum B1 also increased (P < 0.05) ileal mucosal sIgA as well as ileal and cecal SCFA. However, L. plantarum B1 had no effect on intestinal morphology. In conclusion, L. plantarum B1 plays a positive role in broilers. Supplementation during the finisher period or the entire growth period is superior to supplementation during the starter period only.
The interfaces introduced in metals by heterostructural design play crucial roles in mechanical behaviors. Here the effect of gradient interfaces on mechanical behavior was investigated in a ...laminated Cu–30Zn sample composed of coarse-grained and ultrafine-grained layers. Tensile tests revealed a superior strength-ductility synergy with extraordinary strengthening and work hardening. By combining the measurements of height contour and strain distribution using digital image correlation, the development of strain gradient was detected in the near-interface zone during tension, which was caused by the mechanical incompatibilities across interfaces and the synergetic constraint between layers. The intensity of strain gradient in the near-interface zone increased with tensile strain, which was accommodated by the accumulation of geometrically necessary dislocations, thereby resulting in extra back stress and dislocation strengthening.
•Gradient interface in CG/UFG laminate leads to extra strengthening and hardening.•Gradient interface accommodates the strain incompatibility by accumulating strain gradient.•The development of 3D strain gradient around interface is quantitatively visualized.•GNDs accumulation around interface is theoretically derived and experimentally verified.•Gradient interface leads to extra dislocation and back stress strengthening.
We report the first results of a light weakly interacting massive particles (WIMPs) search from the CDEX-10 experiment with a 10 kg germanium detector array immersed in liquid nitrogen at the China ...Jinping Underground Laboratory with a physics data size of 102.8 kg day. At an analysis threshold of 160 eVee, improved limits of 8×10^{-42} and 3×10^{-36} cm^{2} at a 90% confidence level on spin-independent and spin-dependent WIMP-nucleon cross sections, respectively, at a WIMP mass (m_{χ}) of 5 GeV/c^{2} are achieved. The lower reach of m_{χ} is extended to 2 GeV/c^{2}.
Abstract
At the interface between monolayer FeSe films and SrTiO
3
substrates the superconducting transition temperature (
T
c
) is unexpectedly high, triggering a surge of excitement. The mechanism ...for the
T
c
enhancement has been the central question, as it may present a new strategy for seeking out higher
T
c
materials. To reveal this enigmatic mechanism, by combining advances in high quality interface growth,
16
O
$$\leftrightarrow$$
↔
18
O isotope substitution, and extensive data from angle resolved photoemission spectroscopy, we provide striking evidence that the high
T
c
in FeSe/SrTiO
3
is the cooperative effect of the intrinsic pairing mechanism in the FeSe and interactions between the FeSe electrons and SrTiO
3
phonons. Furthermore, our results point to the promising prospect that similar cooperation between different Cooper pairing channels may be a general framework to understand and design high-temperature superconductors.
Aim
To investigate nurses' knowledge, attitudes and practices related to physical restraint in tertiary hospitals and identify the factors that influence physical restraint use.
Background
Physical ...restraint is used to maintain patient safety. Nurses play an important role in the restraint process. It is important to identify their understanding, feelings and approach regarding the use of physical restraint.
Introduction
Physical restraint is widely practiced in hospitals in China. However, it results in a range of serious negative consequences. This article provides a clear description of nurses' knowledge, attitudes and practices related to physical restraint.
Methods
A cross‐sectional survey was conducted. The participants were asked to complete a questionnaire examining their knowledge, attitudes and practices related to physical restraint use. A total of 200 questionnaires were distributed in four tertiary hospitals in Hubei Province, China between August and October 2014.
Results
The nurses' responses indicated a good level of knowledge regarding physical restraint use. However, they held some misconceptions. The nurses' attitudes towards physical restraint tended to be neutral. The nurses were well experienced in the use of physical restraint. Nurses who had received on‐the‐job training performed better than those who had received no training related to knowledge and practices regarding physical restraint use.
Conclusions and implication for nursing/health policy
In‐service training is highly recommended for nursing managers to improve nurses' physical restraint related knowledge and practices. Regulations regarding the use of restraints should be established as soon as possible by healthcare administration system.
Implications for nursing
Nurses should be open to evaluate and improve their views and attitudes regarding effective physical restraint use via multidimensional interventions.
Previous studies have established the link between aberrant microRNA (miRNA) expression and hypoxia in various neoplasms. However, how these hypoxia-related miRNAs modulate tumor progression is still ...unclear. Therefore, the patterns of miRNA in colorectal carcinoma cell lines in response to hypoxia or not were first screened and the hypoxia-induced repression of the miR-15-16 cluster was confirmed. Then, this repression was found to be associated with high tumor stage and poor prognosis in colorectal carcinoma and is shown to promote tumor angiogenesis and metastasis by the loss of restriction of its target gene, fibroblast growth factor-2 (FGF2). Moreover, the general and alterative promoters of the miR-15-16 host (deleted in lymphocytic leukemia 2, DLEU2) were mapped, and three c-Myc/Max binding sites in response to the hypoxia-induced repression of miR-15-16 were further identified. Finally, an enhanced stability of c-Myc/Max heterodimer promoted by increased hypoxia-inducible factor-2α (HIF-2α) was validated, and we also verified that the enhancement contributed to the hypoxia-induced repression of miR-15-16. In brief, the c-Myc-mediated transcriptional repression of miR-15-16 in hypoxia is induced by increased HIF-2α and promoted tumor angiogenesis and hematogenous metastasis by the further loss of post-transcriptional inhibition of FGF2. Our study provides a better understanding of the coping mechanisms in response to tumor hypoxia and may be helpful in developing an effective prognostic marker or treatment target against solid tumors.
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