Use of 3D Laser Scanner for Rock Fractures Mapping

In the process of investigation, design and upgrading of rock slopes, the orientation and spacing of the structural discontinuities or joints in the rock mass are thoroughly mapped in the field so that any unstable blocks can be identified and stabilization measures designed. The orientation of the structural discontinuities is traditionally measured manually using geological compass placed directly at the exposed surfaces. Scaffolding is usually erected so that the geologist can physically access the exposed rock surface. A large number of measurements are usually required in order to obtain a statistical mean of the fracture orientation. With the ongoing advances of digital technology, 3D laser scanning technique can be used to replace direct physical access and large number of manual measurements can be completely eliminated. A prototype system is described in this paper that combines the non-contact measurement technologies of photogrammetric imaging and 3D laser scanning to create dimensionally accurate and pictorially correct 3 dimensional models and orthoimages of a rock fractures. By taking photographs from at least two different locations, lines of sight are mathematically intersected to produce the 3D coordinates of the key reference points in a rock face. Automatic 3D laser scanning unit is then used to produce the 3D coordinates of the entire rock surface. By overlapping the images rectified from photogrammetry technique with the coordinates from 3D laser scanning in an Autodesk 3D Studio Max environment, the coordinates of any objects in the photographs can be selected and their orientation such as dip angle and dip direction calculated automatically. A case study is presented to compare the orientations of fracture planes measured using geological compass and the orientations from the prototype system developed.published_or_final_versio

Monitoring Slope Failure at Kadoorie Agricultural Research Centre with a 3D Laser Scanner

A loosely compacted fill slope with an angle of 33° was constructed at the Kadoorie Agricultural Research Centre of The University of Hong Kong. The height and width were 4.75 m and 9 m respectively. It was constructed by end-tipping method and resulted in a loose state with an initial dry density of 70% of the maximum dry density. Two rows of grouted nails were installed at a grid of 1.5 m x 1.5 m at an inclination of 20° from the horizontal. The slope was brought to failure by subjecting it to surcharge at the slope crest in combination with induced rise in groundwater table and precipitation. Heavy instrumentation comprised in-place inclinometer, vibrating wire piezometers, vibrating wire extensometer, earth pressure cell, tensiometer and strain gauges along soil nails and they had been monitored throughout the test. Surface movement was monitored using a GPS system and a 3D laser scanner. This paper focuses on the use of 3D laser scanner in capturing the formation of cracks and surface movement during the failure. It is found that by overlapping the point clouds generated from the scanner at different time intervals, the surface movement of the slope can be accurately recorded without the need of physically accessing the slope surface. When the slope reaches failure, the use of laser scanning can safely and quickly record the movement and dimension of washout and cracks, providing advantages over conventional survey method. This study shows that the movement obtained from the scanner agrees very well with that from conventional inclinometer reading at the surface. The travel distance of the surcharge block can be easily measured and point cloud can be easily modeled into geometrical shape for further rendering.published_or_final_versio

Pim1 is upregulated by hypoxia in hepatocellular carcinoma and promotes tumor progression

Poster Session - Molecular pathogenesis, molecular pathology, cell biology and translational research: no. P-022INTRODUCTION: Hepatocellular carcinoma (HCC) is the second/third most common fatal cancer in Hong Kong and Southeast Asia associated with frequent tumor recurrence and metastasis. Apart from surgical intervention, tumor control at cellular and molecular levels can possibly improve clinical outcome. HCC is characteristically one of the most rapidly proliferating tumors which often outpace functional blood supply, leading to a regional oxygen deprivation. Therefore, molecular changes induced by hypoxia are attractive therapeutic targets. Overexpression of PIM1, a serine/threonine kinase, has been identified in recent years in solid cancers such as prostate cancer, gastric cancer, and pancreatic cancer. In the latter, PIM1 was upregulated by hypoxia. In this study, we aim at investigating the expression, functional role, and regulatory mechanism of PIM1 in HCC, which have …published_or_final_versio

Down-regulation of TIMP2 by HIF-1α/miR-210/HIF-3α regulatory feedback circuit enhances cancer metastasis in hepatocellular carcinoma

Cancer metastasis is a multistep process that involves a series of tumor-stromal interaction, including extracellular matrix (ECM) remodeling, which requires a concerted action of multiple proteolytic enzymes and their endogenous inhibitors. This study investigated the role of tissue inhibitor of metalloproteinases (TIMP) 2 in the context of hepatocellular carcinoma (HCC) metastasis. We found that TIMP2 was the most significantly down-regulated member among the TIMP family in human HCCs. Moreover, TIMP2 underexpression was frequent (41.8%; 23 of 55) in human HCCs and was significantly associated with liver invasion and poorer survival outcomes of HCC patients. Furthermore, stable silencing of TIMP2 in HCC cell lines enhanced cell invasive ability and ECM degradation associated with formation of invadopodia-like feature, suggesting that TIMP2 is a negative regulator of HCC metastasis. Using an orthotopic tumor xenograft model, we demonstrated that ectopic expression of TIMP2 open reading frame in the highly metastatic HCC cell line, MHCC-97L, significantly reduced HCC progression as well as pulmonary metastasis. Mechanistically, TIMP2 suppression, in a hypoxic environment, was induced through a regulatory feedback circuit consisting of hypoxia-inducible factor (HIF) 1 alpha, microRNA-210 (miR-210), and HIF-3alpha. CONCLUSION: TIMP2 is frequently down-regulated in human HCCs and its down-regulation is associated with aggressive tumor behavior and poorer patient outcome. Its suppression is under the regulation of a novel feedback circuit consisting of HIF-1alpha/miR-210/HIF-3alpha. TIMP2 is an important regulator of ECM degradation and HCC metastasis. (Hepatology 2016;64:473-487).published_or_final_versio

An educational game for teaching clinical practice guidelines to Internal Medicine residents: development, feasibility and acceptability

<p>Abstract</p> <p>Background</p> <p>Adherence to Clinical Practice Guidelines (CPGs) remains suboptimal among internal medicine trainees. Educational games are of growing interest and have the potential to improve adherence to CPGs. The objectives of this study were to develop an educational game to teach CPGs in Internal Medicine residency programs and to evaluate its feasibility and acceptability.</p> <p>Methods</p> <p>We developed the Guide-O-Game^©in the format of a TV game show with questions based on recommendations of CPGs. The development of the Guide-O-Game^©consisted of the creation of a multimedia interactive tool, the development of recommendation-based questions, and the definition of the game's rules. We evaluated its feasibility through pilot testing and its acceptability through a qualitative process.</p> <p>Results</p> <p>The multimedia interactive tool uses a Macromedia Flash web application and consists of a manager interface and a user interface. The user interface allows the choice of two game styles. We created so far 16 sets of questions relating to 9 CPGs. The pilot testing proved that the game was feasible. The qualitative evaluation showed that residents considered the game to be acceptable.</p> <p>Conclusion</p> <p>We developed an educational game to teach CPGs to Internal Medicine residents that is both feasible and acceptable. Future work should evaluate its impact on educational outcomes.</p

PIM1 regulates glycolysis and promotes tumor progression in hepatocellular carcinoma

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Viral Replication in the Nasopharynx Is Associated with Diarrhea in Patients with Severe Acute Respiratory Syndrome

The role of severe acute respiratory syndrome (SARS) coronavirus as an enteric pathogen was investigated in a cohort of 142 patients with SARS who were treated with a standard treatment protocol. Data from daily hematological, biochemical, radiological, and microbiological investigations were prospectively collected, and the correlation of these findings with diarrhea was retrospectively analyzed. Sixty-nine patients (48.6%) developed diarrhea at a mean (± standard deviation [SD]) of 7.6 ± 2.6 days after the onset of symptoms. The diarrhea was most severe at a mean (± SD) of 8.8 ± 2.4 days after onset, with a maximum frequency of 24 episodes per day (median, 5 episodes; range, 3-24 episodes). A higher mean virus load in nasopharyngeal specimens obtained on day 10 after the onset of symptoms was significantly associated with the occurrence of diarrhea (3.1 log 10 vs. 1.8 log 10 copies/mL; P = .01) and mortality (6.2 vs. 1.7 log 10 copies/mL; P<.01). However, diarrhea was not associated with mortality. The lung and the gastrointestinal tract may react differently to SARS coronavirus infection. Additional investigation of the role of SARS coronavirus in the pathogenesis of diarrhea in patients with SARS should be conducted.published_or_final_versio

Clinical and molecular epidemiological features of coronavirus HKU1-associated community-acquired pneumonia

Background. Recently, we described the discovery of a novel group 2 coronavirus, coronavirus HKU1 (CoV-HKU1), from a patient with pneumonia. However, the clinical and molecular epidemiological features of CoV-HKU1-associated pneumonia are unknown. Methods. Prospectively collected (during a 12-month period) nasopharyngeal aspirates (NPAs) from patients with community-acquired pneumonia from 4 hospitals were subjected to reverse-transcription polymerase chain reaction, for detection of CoV-HKU1. The epidemiological, clinical, and laboratory characteristics of patients with CoV-HKU1-associated pneumonia were analyzed. The pol, spike (S), and nucleocapsid (N) genes were also sequenced. Results. NPAs from 10 (2.4%) of 418 patients with community-acquired pneumonia were found to be positive for CoV-HKU1. All 10 cases occurred in spring and winter. Nine of these patients were adults, and 4 had underlying diseases of the respiratory tract. In the 6 patients from whom serum samples were available, all had a 4-fold change in immunoglobulin (Ig) G titer and/or presence of IgM against CoV-HKU1. The 2 patients who died had significantly lower hemoglobin levels, monocyte counts, albumin levels, and oxygen saturation levels on admission and had more-extensive involvement visible on chest radiographs. Sequence analysis of the pol, S, and N genes revealed 2 genotypes of CoV-HKU1. Conclusions. CoV-HKU1 accounts for 2.4% of community-acquired pneumonia, with 2 genotypes in the study population. Without performance of diagnostic tests, the illness was clinically indistinguishable from other community-acquired pneumonia illnesses. © 2005 by the Infectious Diseases Society of America. All rights reserved.published_or_final_versio

SENP1 promotes hypoxia-induced cancer stemness by HIF-1α deSUMOylation and SENP1/HIF-1α positive feedback loop

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