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There is a lack of research on the mechanisms by which isolation piles affect displacements in deep soil layers and the use of isolation piles to control the displacement and deformation of the existing tunnels adjacent to deep excavations. This paper examines a large, deep excavation project in which isolation piles were used to protect a nearby existing tunnel. A finite-element model that considers the small-strain characteristics of the soil was used to simulate this project. After the numerical model is verified, it is used in a parametric analysis of the mechanisms by which isolation piles control the displacement of deep soil layers and the deformation of tunnels near excavations. The results show that isolation piles have both a barrier effect and a traction effect on the surrounding soil and adjacent tunnels. When the traction effect is larger, isolation piles can exacerbate the horizontal displacement of the soil and tunnel within a certain depth range and actually increase tunnel deformation. Burying the isolation piles reduces this traction effect and improves their ability to isolate tunnels from displacement. All else being equal, isolation piles more efficiently control deformation if they are near the tunnel.

Lower cervical spine dislocation remains a surgical challenge.

The canine is the most important large animal model for testing novel hemophilia A (HA) treatment. It is often necessary to use canine factor VIII (cFIII) gene or protein for the evaluation of HA treatment in the canine model. However, different biological properties between cFVIII and human FVIII (hFVIII) indicated that the development of novel HA treatment may require careful characterization of non-human FVIII. To investigate whether the data obtained using cFVIII can translate to HA treatment in human, we analyzed the differential biological properties of canine heavy chain (cHC) and light chain (cLC) by comparing with human heavy chain (hHC) and light chain (hLC). The secretion of cHC was 5–30-fold higher than hHC, with or without light chains (LCs). cHC+hLC group exhibited ~18-fold increase in coagulation activity compared with hHC+hLC delivery by recombinant adeno-associated viral vectors. Unlike hHC, the secretion of cHC was independent of LCs. cLC improves the specific activity of FVIII by two- to threefold compared with hLC. Moreover, the cLC, but not cHC, contributes to the higher stability of cFVIII. Our results suggested that the cFVIII expression results in the canine model should be interpreted with caution as the cHC secreted more efficiently than hHC and cLC exhibited a more active and stable phenotype than hLC.

OBJECTIVE: MicroRNA-221 (miR-221), which is located on chromosome X, is an oncogenic microRNA that is involved in several human malignancies. This study aimed to characterize the role of miR-221 in the initiation and malignant progression of gastric cancer. METHODS: The level of miR-221 expression in 92 pairs of primary gastric tumour tissue and adjacent nontumour tissue was quantified by real-time reverse transcription—polymerase chain reaction. The relationship between the miR-221 level and clinicopathological features was explored. RESULTS: MiR-221 was up-regulated in 88% (81/92) of gastric cancer tissue samples compared with their paired adjacent nontumour tissue samples. High expression of miR-221 showed a significant correlation with advanced tumour—node—metastasis stage, local invasion and lymphatic metastasis. Univariate and multivariate Cox proportional hazard regression analyses revealed that miR-221 overexpression was an unfavourable prognostic factor for overall survival in patients with gastric cancer. CONCLUSIONS: These findings suggest that miR-221 is a novel prognostic indicator in gastric cancer and may be a potential target for diagnosis and gene therapy.

As research advances with ever increasing complexity and quantity of algorithms for MRI, it becomes increasingly difficult to research, consolidate, and access algorithms without considerable effort to either implement or integrate software repositories in a clinical researcher's analysis pipeline. To this end, we have developed a framework with the aim of improving the accessibility of sophisticated musculoskeletal MR imaging processing techniques and facilitating the creation of new multi-platform image processing pipelines. This software application offers an intuitive, visual method for the development of analysis pipelines for MR reconstruction, segmentation, data visualization, and quantitative analysis. We hope this framework will encourage the collaboration of researchers by facilitating the traditionally difficult task of integrating MR algorithms into clinical imaging processing pipelines.

A frame multiresolution (FMRA for short) orthogonalwavelet is a single-function orthogonal wavelet such that theassociated scaling space V0 admits a normalized tight frame(under translations). In this article, we prove that for anyexpansive matrix A with integer entries, there existA-dilation FMRA orthogonal wavelets. FMRA orthogonal waveletsfor some other expansive matrix with non integer entries are also discussed.

The hydrolysis of magnesium methoxide in methanol or methanol−toluene solvents with a water-to-methoxide molar ratio of 2 has been studied. The gel obtained from the hydrolysis of magnesium methoxide appears to be polymeric based on the mass fractal dimensions and TEM micrographs. The presence of toluene accelerates the hydrolysis and gelation processes. The fractal dimensions of the wet gels obtained in the absence and in the presence of toluene were 2.22 and 1.80, respectively. Both of these observations indicate that the presence of toluene changes the fractal growth from a reaction-limited to a diffusion-limited growth. In either case, the hydrolysis is only completed partially and produces an intimate gel of MgO−Mg(OH)2−Mg(OH)(OCH3). The N2 BET surface area of the dry gel, obtained with a toluene to methanol volume ratio of 1.60, is 1011 m²/g, which is 1.74 times as large as that of the gel obtained in the absence of toluene.

The representation of the visual field in the 17/18 border region of the cat's visual cortex, and the layout of orientation and ocular dominance columns, were studied by making many closely spaced electrode penetrations into the superficial layers of the flattened dorsal region of the marginal gyrus and recording response properties at each location. The 17/18 border region was defined by measuring the change in the horizontal component of receptive field position within the gyrus: as the position of the recording electrode moved from medial to lateral, the receptive fields moved towards the vertical midline, indicating that the electrode was in area 17; as penetrations were made in increasingly lateral positions, the trend reversed, and receptive field positions moved away from the midline, indicating that the electrode was in area 18. The receptive fields of cells close to the border straddled, or lay within 2°–3° on either side of the vertical midline. In addition, patches of cortex were sometimes encountered in which cells had receptive field centers located up to 7° in the ipsilateral visual field. Experiments in which maps were made in the left and right hemispheres of a single animal showed that these patches had a complementary distribution in the two hemispheres. Cells within the patches behaved as though driven by Y-cell inputs: they usually had large receptive fields and responded to rapidly-moving stimuli. They were broadly tuned for orientation and strongly dominated by the contralateral eye. Fourier spectral analysis of orientation selectivity maps showed that iso-orientation bands had an average spacing of 1.14 ± 0.1 mm and tended to be elongated in a direction orthogonal to the 17/18 border. Individual bands crossed the border without obvious interruption, although singularities (points of discontinuity in the layout of orientations) were more frequently observed in the border region than in adjacent areas. Two dominant periodicities could be measured in the maps of ocular dominance, one at around 0.8 ± 0.2 mm and a second at 2.0 ± 0.3 mm. No constant direction of elongation was noted. These are close to the periods present within areas 17 and 18 respectively.

The functions of interhemispheric axons linking the borders between cortical areas 17 and 18 on the two sides of the brain were investigated by two techniques. A well‐matched sample of neurones was recorded in the 17/18 border region before and after an extensive lesion was made in the corresponding part of the other hemisphere. The proportion of binocularly driven cells fell from 96% to 67%, confirming the results of Dreher & Cottee (1975). Orientation‐and direction‐selectivity, as well as the responsiveness of the population of neurones, seemed unaltered. The reduction in binocularity was much less convincing for cells in the body of area 17, even very close to the callosal‐recipient zone. Reversible cooling of the 17/18 border had no effect on the few cells recorded outside the callosal zone in the other hemisphere nor on eighteen of the thirty‐five cells recorded in the callosal zone. However, in ten cells the receptive field disappeared completely in one eye; in five cells there was a general reduction in responsiveness; two cells lost a portion of the receptive field, on the ipsilateral side, in both eyes. The receptive fields that were apparently transmitted via the corpus callosum lay around the vertical meridian of the visual field and were not restricted to the visual hemifield ipsilateral to the receiving hemisphere: their distribution overlapped that provided by the direct geniculo‐cortical input. The principal function of the callosal projection between the 17/18 borders may be to contribute to binocular convergence on cortical cells and perhaps to play a part in stereoscopic vision.

Electrophysiological mapping techniques were used to determine the representation of the central field of vision in the superior colliculus of the albino rat. The retinotopic map for the contralateral eye is similar to that found in other mammals. There is an unexpected extensive binocular segment subserving the central 40° of the ipsilateral hemifield as well as the central 40° of the contralateral hemifield in the rostrolateral portion of the tectum.

Four hundred and fifteen cells were recorded in the binocular segment of the visual cortex in the albino rat. Cells encountered were mainly dominated by the contralateral eye. The percentage of binocularly-driven cells increased as the electrode was moved towards the border between areas 17 and 18a. Ninety percent of the cells studied in the region of the border could be driven by electrical stimulation applied at the corresponding site in the opposite hemisphere. Within area 17, however, there were only about 30% of such cells. Through the combined use of electrical stimulation and reversible cortical cooling, two types of contributions by callosal fibres were revealed. One is that the callosal fibres constitute the only inputs from the ipsilateral eye to a cell. The other is that the callosal input provides ipsilateral reinforcement to a binocular cell. These results are compatible with neuroanatomical findings and show that binocularity of visual cortical cells in this animal depends, to a great degree, on the function of callosal fibres.