Steep terrain and high a frequency of tropical rainstorms make landslide occurrence on natural terrain a common phenomenon in Hong Kong. This paper reports on the use of a Geographical Information ...Systems (GIS) database, compiled primarily from existing digital maps and aerial photographs, to describe the physical characteristics of landslides and the statistical relations of landslide frequency with the physical parameters contributing to the initiation of landslides on Lantau Island in Hong Kong. The horizontal travel length and the angle of reach, defined as the angle of the line connecting the head of the landslide source to the distal margin of the displaced mass, are used to describe runout behavior of landslide mass. For all landslides studied, the horizontal travel length of landslide mass ranges from 5 to 785 m, with a mean value of 43 m, and the average angle of reach is 27.7°. This GIS database is then used to obtain a logistic multiple regression model for predicting slope instability. It is indicated that slope gradient, lithology, elevation, slope aspect, and land-use are statistically significant in predicting slope instability, while slope morphology and proximity to drainage lines are not important and thus excluded from the model. This model is then imported back into the GIS to produce a map of predicted slope instability. The results of this study demonstrate that slope instability can be effectively modeled by using GIS technology and logistic multiple regression analysis.
Summary
Background
Hepatitis B virus (HBV) is the leading cause of hepatocellular carcinoma (HCC) worldwide. It remains incompletely understood in the real world how anti‐viral therapy affects ...survival after HCC diagnosis.
Methods
This was an international multicentre cohort study of 2518 HBV‐related HCC cases diagnosed between 2000 and 2015. Cox proportional hazards models were utilised to estimate hazard ratios (HR) with 95% (CI) for anti‐viral therapy and cirrhosis on patients' risk of death.
Results
Approximately, 48% of patients received anti‐viral therapy at any time, but only 17% were on therapy at HCC diagnosis (38% at US centres, 11% at Asian centres). Anti‐viral therapy would have been indicated for >60% of the patients not on anti‐viral therapy based on American criteria. Patients with cirrhosis had lower 5‐year survival (34% vs 46%; P < 0.001) while patients receiving anti‐viral therapy had increased 5‐year survival compared to untreated patients (42% vs 25% with cirrhosis and 58% vs 36% without cirrhosis; P < 0.001 for both). Similar findings were seen for other patient subgroups by cancer stages and cancer treatment types. Anti‐viral therapy was associated with a decrease in risk of death, whether started before or after HCC diagnosis (adjusted HR 0.62 and 0.79, respectively; P < 0.001).
Conclusions
Anti‐viral therapy improved overall survival in patients with HBV‐related HCC across cancer stages and treatment types but was underutilised at both US and Asia centres. Expanded use of anti‐viral therapy in HBV‐related HCC and better linkage‐to‐care for HBV patients are needed.
Landslides can result in enormous casualties and huge economic losses in mountainous regions. In order to mitigate landslide hazard effectively, new methodologies are required to develop a better ...understanding of landslide hazard and to make rational decisions on the allocation of funds for management of landslide risk. Recent advances in risk analysis and risk assessment are beginning to provide systematic and rigorous processes to enhance slope management. In recent years, risk analysis and assessment has become an important tool in addressing uncertainty inherent in landslide hazards.
This article reviews recent advances in landslide risk assessment and management, and discusses the applicability of a variety of approaches to assessing landslide risk. Firstly, a framework for landslide risk assessment and management by which landslide risk can be reduced is proposed. This is followed by a critical review of the current state of research on assessing the probability of landsliding, runout behavior, and vulnerability. Effective management strategies for reducing economic and social losses due to landslides are described. Problems in landslide risk assessment and management are also examined.
The Support Vector Machine (SVM) is an increasingly popular learning procedure based on statistical learning theory, and involves a training phase in which the model is trained by a training dataset ...of associated input and target output values. The trained model is then used to evaluate a separate set of testing data. There are two main ideas underlying the SVM for discriminant-type problems. The first is an optimum linear separating hyperplane that separates the data patterns. The second is the use of kernel functions to convert the original non-linear data patterns into the format that is linearly separable in a high-dimensional feature space. In this paper, an overview of the SVM, both one-class and two-class SVM methods, is first presented followed by its use in landslide susceptibility mapping. A study area was selected from the natural terrain of Hong Kong, and slope angle, slope aspect, elevation, profile curvature of slope, lithology, vegetation cover and topographic wetness index (TWI) were used as environmental parameters which influence the occurrence of landslides. One-class and two-class SVM models were trained and then used to map landslide susceptibility respectively. The resulting susceptibility maps obtained by the methods were compared to that obtained by the logistic regression (LR) method. It is concluded that two-class SVM possesses better prediction efficiency than logistic regression and one-class SVM. However, one-class SVM, which only requires failed cases, has an advantage over the other two methods as only “failed” case information is usually available in landslide susceptibility mapping.
Abstract
Various methods of evaluating a humectant’s moisture retention have unique mechanisms. Hence, for designing advanced or efficient ingredients of cosmetic products, a clear understanding of ...differences among methods is required. The aim of this study was to analyze the moisture-retention capacity of glycerin, a common ingredient in cosmetic products. Specifically, this study applied gravimetric analysis, transepidermal water loss (TEWL) analysis, and differential scanning calorimetry (DSC) to examine the evaporation of glycerin solutions of different concentrations. The results revealed that the moisture-retention capacity of glycerin increased with the glycerin concentration from 0 to 60 wt%, and glycerin at concentration of 60–70 wt% did not exhibit weight change during the evaporation process. When the glycerin concentration exceeded 70 wt%, moisture sorption occurred in the glycerin solution. Furthermore, the results revealed a deviation between the evaporation rates measured using gravimetric analysis and those measured using TEWL analysis. However, normalizing the results of these analyses yielded the relative evaporation rates to water, which were consistent between these two analyses. DSC thermograms further confirmed the consistent results and identified two hydrated water microstructures (nonfreezable water and free water) in the glycerin solutions, which explained why the measured evaporation rate decreased with the glycerin concentration. These findings can be applied to prove the moisture-retention capacity of a humectant in cosmetic products by different measuring methods.
In recent years, Heifangtai Plateau in Gansu Province, China, has received significant attention as a loess region in which landslides frequently occur. This study aims to examine the soil behavior ...and failure mechanism(s) of loess slopes subjected to water infiltration. High-quality samples were retrieved behind the failure plane of a landslide in Heifangtai. Three sets of stress path tests were conducted to mimic the process of loess slope failures; these tests include undrained compression on anisotropically consolidated saturated samples, drained shear by decreasing mean effective stress at constant axial load on saturated samples, and wetting by decreasing matric suction at constant axial load on unsaturated samples. Loess behavior was evaluated in terms of shear strength, deformation upon shearing, critical state, state parameter, and soil water characteristic curve. Three major observations were drawn from the test results. First, the anisotropically consolidated saturated loess exhibits a noticeable strain-softening behavior upon undrained compression. The peak shear strength is mobilized at less than 1% axial strain. The ultimate shear strength is only 20–30% of the peak value. Second, when subjected to shear by decreasing mean effective stress at constant axial load, the saturated loess exhibits sudden failure when the confining stress is low. At higher stresses, the soil exhibits progressive failure. Third, unsaturated loess deforms progressively when subjected to a reduction in matric suction (i.e., wetting) at constant axial load. The failure mechanisms of the loess slopes are discussed based on the experimental findings.
•The failure mechanisms of loess slopes are examined by performing stress path tests.•The behavior of anisotropically consolidated saturated loess is presented.•The failure of saturated soil is mimicked by rising pore pressure at constant load.•The failure of unsaturated soil is mimicked by reducing suction at constant load.•The soil–water characteristic curves of loess are presented.
Summary
Background
Deregulation of mammalian target of rapamycin (mTOR) signalling is common in human hepatocellular carcinoma (HCC).
Aim
To determine the maximum tolerated dose (MTD) of the oral ...mTOR inhibitor everolimus in advanced HCC patients.
Methods
Patients with locally advanced or metastatic HCC (Child‐Pugh class A or B) were enrolled in an open‐label phase 1 study and randomly assigned to daily (2.5–10 mg) or weekly (20–70 mg) everolimus in a standard 3 + 3 dose‐escalation design. MTD was based on the rate of dose‐limiting toxicities (DLTs). Secondary endpoints included safety, pharmacokinetics and tumour response. In a post hoc analysis, serum hepatitis B virus (HBV) DNA levels were quantified.
Results
Thirty‐nine patients were enrolled. DLTs occurred in five of 21 patients in the daily and two of 19 patients in the weekly cohort. Daily and weekly MTDs were 7.5 mg and 70 mg respectively. Grade 3/4 adverse events with a ≥10% incidence were thrombocytopenia, hypophosphataemia and alanine transaminase (ALT) elevation. In four hepatitis B surface antigen (HBsAg)‐seropositive patients, grade 3/4 ALT elevations were accompanied by significant (>1 log) increases in serum HBV levels. The incidence of hepatitis flare (defined as ALT increase >100 IU/mL from baseline) in HBsAg‐seropositive patients with and without detectable serum HBV DNA before treatment was 46.2% and 7.1% respectively (P < 0.01, Fisher exact test). Disease control rates in the daily and weekly cohorts were 71.4% and 44.4% respectively.
Conclusions
The recommended everolimus dosing schedule for future hepatocellular carcinoma studies is 7.5 mg daily. Prophylactic anti‐viral therapy should be mandatory for HBsAg‐seropositive patients (ClinicalTrials.gov NCT00390195).
The polarized absorption spectra of crystalline pentacene are obtained for excitation normal to the ab herringbone plane by measuring transmitted light in ultrathin crystals. The spectral line shapes ...for excitation polarized along b and orthogonal to b are analyzed theoretically using a Holstein-like Hamiltonian which includes both Frenkel and charge transfer (CT) excitons represented in a multiparticle basis set. The model agrees with prior estimates regarding the strong CT contribution (≈45%) of the exciton responsible for the b-polarized lower Davydov component. The polarization resolution allows one to also establish the nature of the upper Davydov component, which is found to contain far less CT content (≈15%), as well as the natures of the higher-energy vibronic excitons, which are found to consist of a complex mixture of Frenkel one- and two-particle states and CT excitons. Generally, the spectrum polarized along b displays J-aggregate-like vibronic signatures while the spectrum polarized orthogonal to b displays H-aggregate-like vibronic signatures. The assignment is entirely consistent with the calculated exciton band dispersions which agree well with the measured ones.
A geo-environmental evaluation for urban land-use planning often requires a large amount of spatial information. Geographic information systems (GIS) are capable of managing large amounts of ...spatially related information, providing the ability to integrate multiple layers of information and to derive additional information. A GIS-aid to the geo-environmental evaluation for urban land-use planning is illustrated for the urban area of Lanzhou City and its vicinity in Northwest China. This evaluation incorporates topography, surficial and bedrock geology, groundwater conditions, and historic geologic hazards. Urban land-use is categorized according to the types of land-use and projects planned, such as high-rise building, multi-storey building, low-rise building, waste disposal, and natural conservation. Multi-criteria analysis is performed to evaluate development suitability of the geo-environment for each category, according to appropriately measured and weighted factors. A suitability map for each category is developed using an algorithm that combines factors in weighted linear combinations. It is demonstrated that the GIS methodology has high functionality for geo-environmental assessment.
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