Moving Stationary State of Exciton-Phonon Condensate in Cu2O

We explore a simple theoretical model to describe the properties of Bose condensed para-excitons in Cu2O. Taking into account the exciton-phonon interaction and introducing a coherent phonon part of the moving condensate, we derive the dynamic equations for the exciton-phonon condensate. Within the Bose approximation for excitons, we discuss the conditions for the moving inhomogeneous condensate to appear in the crystal. We calculate the condensate wave function and energy and a collective excitation spectrum in the semiclassical approximation. The stability conditions of the moving condensate are analyzed by use of Landau arguments, and two critical velocities appear in the theory. Finally, we apply our model to describe the recently observed interference between two coherent exciton-phonon packets in Cu2O.Comment: 20 pages (LaTeX), one figure (.ps) incorporated by epsf. Submitted to Phys. Stat. Sol (B

The association of HBV core promoter double mutations (A1762T and G1764A) with viral load differs between HBeAg positive and anti-HBe positive individuals: A longitudinal analysis

Background/Aims: Although there have been a few reports regarding the effect of basal core promoter (BCP) double mutations (A1762T and G1764A) on hepatitis B viral loads, the association remains uncertain. We aim to determine the association after controlling for HBeAg - a strong confounding factor.Methods: We selected randomly 190 individuals from a Chinese cohort of 2258 subjects for cross-sectional analysis and 56 of the 190 for longitudinal analysis of viral loads.Results: In multivariable analysis of the cross-sectional data, BCP double mutations are significantly associated with lower viral loads in HBeAg positive subjects but no difference was found in anti-HBe positive subjects. Triple mutations at nucleotide (nt) 1753, 1762 and 1764 and mutations between nt 1809 and 1817, precore stop mutation (nt 1896) and genotype are not associated with viral loads in either HBeAg or anti-HBe positive subjects. Analysis of the longitudinal data yielded similar results to the cross-sectional data. Viral loads differ significantly between individuals infected with wild-type and BCP double mutations prior to HBeAg seroconversion but this difference is lost after seroconversion.Conclusions: BCP double mutations are associated with lower viral loads in HBeAg positive individuals but have no effect on the viral loads of anti-HBe positive individuals. (C) 2008 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved

One Thousand Dollar Assist Heart Pump for Patients from Developing Countries

In spite of continuous improvements in device design and applications, the profound use of heart pump has been limited because of its high price. The available clinically applied heart pump costs mostly about 100 thousands US Dollars. The author has since long tried to develop a heart pump costing only 1000 Dollars for recovery or bridge to heart transplantation therapies. The device is a radially driven centrifugal pump with a brush-less DC motor and a streamlined impeller. Its bearing is rolling bearing using 4 to 6 needles, manufactured by special wear-proof polythene with super-high-molecular weight, thus the service life achieves more than 10 years. To avoid thrombus formation, a special purge system is introduced to the bearing, allowing the saline with heparin to be infused through the bearing into the pump. The bearing, therefore, keeps working in the saline, and absolutely no thrombus will be formed along the bearing. Animal experiments demonstrated that a 30 mL fluid infusion per hour is enough to prevent thrombus formation. With these improvements, the impeller pump has continuously run for 14 months in the laboratory, and no bearing wear can be measured. The device, weighing 150 g, is fully implantable, consumes approximately 9.6 W, delivers a 9Lmin-1 blood flow against a 120 mmHg mean pressure, and reaches a highest total efficiency of 24.7% for the motor (including the controller) and the pump. The device has been used in animal experiments together with an American artificial lung for more than one month in the University of Texas and also in human trials in the Taiwan University

How is Business Adapting to Climate Change Impacts Appropriately? Insight from the Commercial Port Sector

Adaptation to climate change impacts is a key research topic in business ethics that poses substantial implications on the good lives of human beings. The commercial port sector is a highly relevant study focus with its pivotal roles in supply chains and international trade. Hence, it is important to investigate whether the port planning system and practice is appropriate in tackling climate change impacts. But beforehand, we must thoroughly understand the attitude and behaviors of port planners and operators on ports’ climate adaptation planning. Through a survey towards 21 ports (seaports and dry ports) in Canada, the paper investigates the attitude and behaviors of port planners and operators on ports’ climate adaptation planning. Towards the end, we propose a new approach so as to enable port stakeholders to carry out climate adaptation planning effectively. The paper offers important insight to researchers to investigate the ways in developing effective climate adaptation plans and practice for ports and other business sectors. © 2016 Springer Science+Business Media Dordrech

The Attractiveness of Ports in West Africa: Some Lessons from Shipping Lines' Port Selection

This paper investigates the attractiveness of ports in West Africa through the development of a container shipping lines' port choice methodology. Although many multi-criteria decision-making methods have been developed and applied to facilitate a rational port choice process, few have investigated the criteria used by shipping lines when selecting ports in West Africa. With the rapid economic development of West Africa, the task of establishing a rational model to guide shipping lines to choose their favourite ports in the region becomes urgent. In this work, 16 criteria are identified to assist shipping lines in port choice from four perspectives including adequate infrastructure, port location, port charge, and port administration/port efficiency. In order to quantitatively evaluate these criteria, an analytical hierarchy process approach is used to make use of subjective judgements to compensate the incompleteness of objective data. One of the important findings from this study is that port infrastructure is the most crucial criterion in terms of the port attractiveness in West Africa. It is followed by port draught, political stability, market size/cargo volume, and international networks. The research outcomes also indicate that the port of Abidjan is the most attractive container port in West Africa, followed by Dakar when all the identified important criteria are taken into account

An endophytic Taxol-producing fungus BT2 isolated from Taxus chinensis var. mairei

BT2, a newly isolated endophytic fungus from Taxus chinensis var. mairei, was observed to produce Taxol. Besides Taxol, a potent anticancer drug, BT2 could also yield taxane baccatin III, which was an important intermediate for Taxol and semi-synthesis of Taxol in industry. The isolation of such a fungusmay provide a promising alterative approach to produce Taxol, and BT2 can serve as a potential material for fungus engineering to improve Taxol productio

Psychological drivers of hotel guests’ energy‐saving behaviours—empirical research based on the extended theory of planned behaviour

The hospitality industry is an important energy consumer and carbon emitter. Behaviour-driven energy conservation is a strategy with great promise to strengthen the energy efficiency of hotel buildings. The aim of this study is to explore the driving psychological factors of hotel guests’ energy-saving intentions and behaviours. This paper constructs two extensions of the theory of planned behaviour (TPB) with personal norms, past behaviours, and self-determined motivation to explain the guests’ energy-saving behaviour in hotel buildings. This research compares the explanatory power of the original TPB and two extensions with structural equation modelling. The analysis is based on 530 valid, self-reported data from 827 surveyed hotel guests in Shanghai. The analysis suggests that the extended model gains greater explanatory power in predicting the behaviour patterns by employing the above three additional factors. In addition, self-determined motivation presents a more significant impact than other more developed TPB predictors, such as intention and perceived behaviour control. Aside from that, past behaviour replaces attitude as the most critical predictor of hotel energy-saving intention in the extended models. In addition to the existing interventions in office and residential buildings, the research highlights the role of self-determination in hotel energy conservation and further emphasises the long-term benefit of encouraging pro-environmental behaviours in hotel guests. The findings expand the existing research on pro-environmental behaviours and will contribute to energy-saving behaviour intervention in hotel buildings and policy formulations for sustainable hotel operation and maintenance.</jats:p

Improvements and Applications of AMS Radiocarbon Measurement at Peking University

AMS radiocarbon measurements were started at Peking University in 1992 with a modified HICONEX 834 ion source. Some archaeological samples were measured at a sensitivity of 10(-14) with ca. 1.7% precision for modern samples. We have made many improvements in our first two years of operation: a high-intensity Cs sputtering ion source was installed; the graphite sample preparation technique was investigated; and the system stability has been improved. The blank sample background is currently ca. 0.006 MC and a precision within 1% can be reached for modern samples. Geological, archaeological, environmental and biomedical samples can be measured routinely. We present some typical applications.Geochemistry &amp; GeophysicsSCI(E)

Quantitative expression of osteopontin in nasal mucosa of patients with allergic rhinitis: effects of pollen exposure and nasal glucocorticoid treatment

<p>Abstract</p> <p>Background</p> <p>Osteopontin (OPN) is a multifunctional cytokine that has been primarily investigated in Th1 diseases. Recently, it has also been implicated in Th2-mediated allergic diseases, such as asthma. The expression of OPN in allergic rhinitis (AR) is currently unknown, as is the effect of intranasal glucocorticosteroids (GCs) on that expression.</p> <p>Methods</p> <p>Subjects with AR were randomised to receive treatment with fluticasone propionate (FP) (n = 12) or a placebo (n = 16) over the grass pollen season and nasal biopsies were taken prior to, and during the season. OPN expression in the nasal mucosa was examined with immunohistochemistry. Healthy non-AR controls (n = 5) were used as a comparator.</p> <p>Results</p> <p>OPN expression was detected in epithelial cells, subepithelial infiltrating/inflammatory cells and cells lining the vessels and glands of all subjects. Comparison of the pre- and peak-pollen season biopsy sections in placebo treated patients revealed no increase in OPN expression during the grass pollen season (5.7% vs 6.4%). Treatment with a local glucocorticosteroid did not alter the expression of OPN during pollen exposure (6.2% vs 6.7%).</p> <p>Conclusion</p> <p>OPN has been increasingly associated with the pathogenesis of various Th2-mediated diseases. However, our finding that the OPN expression in the nasal mucosa of AR patients is not significantly affected by allergen exposure and is comparable to that of the healthy controls, suggests that intracellular OPN is not directly involved in the pathogenesis of allergic rhinitis.</p