Relaxation and diffusion are general and common phenomena in many branches of condensed matter physics, chemistry and materials sciences. In disordered and partially ordered systems the classes of ...materials include liquids, colloids, polymers, rubbers, plastic crystals, biomolecules, ceramics, electrolytes, fuel cell materials, molten salts, glasses, and etc. Each class is further subdivided into many different types of materials. For example, glasses vary from metallic glasses, oxide glasses, chalcogenide glasses, polymeric and organic glasses, and each form a separate discipline. In past years research has suffered from undue fragmentation in terms of individual classes of materials. Dr. Ngai was one of the few who recognized the existence of a remarkable universality of relaxation and diffusion properties across the diverse classes of materials, and he suggested that some yet undiscovered fundamental physics is behind this universality Beginning in 1979 with the publication of two articles in Comment Solid State Physics, Dr. Ngai launched an interdisciplinary study of relaxation and diffusion that has continued to the present. At this time, experimental evidence of universal behavior are plentiful and well substantiated. Dr. Ngai has also created a theoretical framework to characterize, correlate and interpret these universal properties. This book will be of interest to a large number of researchers across many disciplines.
Background. Better understanding of complications and outcomes of adults hospitalized with respiratory syncytial virus (RSV) infection is necessary. Methods. A retrospective cohort study was ...conducted on all adults (≥18 years) admitted to 3 acute care general hospitals in Hong Kong with virologically confirmed RSV infection during 2009–2011 (N = 607). Adults hospitalized for seasonal influenza during the period were used for comparison (n = 547). Both infections were prospectively diagnosed following a standard protocol. Independent reviews of chest radiographs were performed by radiologists. Main outcome measures were all-cause death, respiratory failure requiring ventilatory support, and hospitalization duration. Cox proportional hazards models were used for analyses. Results. The mean age of RSV patients was 75 (SD, 16) years; 87% had underlying conditions. Lower respiratory and cardiovascular complications were diagnosed in 71.9% (pneumonia, 42.3%; acute bronchitis, 21.9%; chronic obstructive pulmonary disease/asthma exacerbation, 27.3%) and 14.3% of patients, respectively; 12.5% had bacterial superinfections. Supplemental oxygen and ventilatory support were required in 67.9% and 11.1%, respectively. Crude all-cause mortality was 9.1% and 11.9% within 30 days and 60 days, respectively; mean length of stay of survivors was 12 (SD, 13) days. Advanced age, radiographic pneumonia, requirement for ventilation, bacterial superinfection, and elevated urea level and white blood cell count were independently associated with poorer survival. Systemic corticosteroid use was associated with longer hospitalization and secondary infections. The overall outcomes of survival and length of stay were not significantly different from those in influenza. Conclusions. RSV can cause severe lower respiratory complications in older adults, resulting in respiratory failure, prolonged hospitalization, and high mortality similar to seasonal influenza. Corticosteroids did not seem to improve outcomes. The unmet need for antiviral therapy and vaccination against RSV in adults should be promptly addressed.
Academic research into radio frequency identification (RFID) has proliferated significantly over the last few years, to the point where journals (
Production and Operations Management, International ...Journal of Production Economics, IEEE Systems Journal, and
IEEE Transactions on Automation Science and Engineering) are producing special issues on the topic. In this paper, we present a literature review of 85 academic journal papers that were published on the subject between 1995 and 2005. We organize these studies into four main categories: technological issues, applications areas, policy and security issues, and other issues. All of the papers in the review are allocated to the main and sub-categories based on their main focus. Our analysis of these papers provides useful insights on the anatomy of the RFID literature, and should aid the creation and accumulation of knowledge in this domain. A comprehensive list of references is also presented. It is hoped that the review will be a good resource for anyone who is interested in RFID research, and will help to stimulate further interest in this area. The implications for RFID researchers and practitioners and suggestions for future research areas are discussed.
Background. A need for quadrivalent vaccines to cover both lineages of influenza B has been raised. Information on the circulation status of influenza B lineages and the associated hospitalization ...rates is important to assist evidence-based decision making. This retrospective study revealed the situation in a subtropical city over a 10-year period. Methods. Sequences of 268 influenza B isolates were analyzed to identify the circulating pool of virus lineages for each year. Hospital records and population census data were used to estimate annual age-specific hospitalization rates. Results. Cocirculation with 2 influenza B lineages was found in 9 of the 10 years. Only in 6 of the 10 years had the vaccine strain successfully matched with the lineage that was found in >50% of the circulating pool. Six years were predominated by one lineage (occupying >80% of the circulating pool), and these years had higher (average, 1.4-fold) hospitalization rates. Matching between vaccine and circulating lineage was achieved only in 2 of the 6 "predominated years." The Yamagata lineage accounted for most (5/6) of the predominated years. Overall, 24% of influenza admissions were due to influenza B, and influenza B contributed to a higher proportion (41.9%) among children and young teenagers (5–14 years old). Conclusions. Cocirculation with 2 influenza B lineages is common in the subtropical region. To predict the next predominant lineage proves to be difficult. Influenza B accounts for a substantial fraction of influenza-associated hospitalizations, especially among children and young teenagers. Quadrivalent vaccines may improve the effectiveness of influenza vaccination programs.
A longstanding problem in the Brillouin light scattering (BLS) study of polymers is the relaxation times τBLS(T) being more than an order of magnitude shorter than the α-relaxation times τα(T) ...determined by dielectric, depolarized light scattering (DLS), and molecular dynamics simulations. In tackling the problem, τBLS(T) was identified with the relaxation time τ0(T) of the primitive relaxation in the coupling model, which can be calculated from τα(T) and the stretch exponent βK of the Kohlrausch correlation function for the α-relaxation.. The problem was solved by finding that indeed τ0(T) is in good agreement with τBLS(T). A recent work performed the neutron spin echo study of the structural α-relaxation of the network ionic liquid ZnCl2 and found the same anomaly as polymers. The α-relaxation time τNSE(T) from neutron spin echo (NSE) as well as the α-relaxation time τDLS(T) from DLS of ZnCl2 are much longer than τBLS(T) from BLS obtained before by several research groups. The finding of the same anomaly in ZnCl2 and polymers with very different chemical and physical structures offers an opportunity to critically test the explanation given before. The test was carried out by calculating the primitive relaxation times τ0,DLS(T) and τ0,NSE(T) from τDLS(T) and τNSE(T), respectively, in zinc chloride. Good agreements of τBLS(T) from BLS with τ0,DLS(T) and τ0,NSE(T) were found and thus the explanation given for polymers remains valid for ZnCl2. The test was extended to glycerol by comparing τBLS(T) with τ0,ICNS(T) and τ0,CNS(T) calculated from the α-relaxation time τICNS(T) and τCNS(T) from incoherent and coherent neutron scattering, respectively. There is good agreement between τBLS(T) and τ0,ICNS(T) in glycerol. There is also semiquantitative agreement of τBLS(T) with τ0,DS(T) from dielectric spectroscopy as well as τ0,CNS(T). Thus, the explanation for polymers is verified in the two very different glass formers, ZnCl2 and glycerol, and it is an advancement in the application of BLS to study the dynamics of glass formers.
Studying cytokine/chemokine responses in severe influenza infections caused by different virus subtypes may improve understanding on pathogenesis.
Adults hospitalized for laboratory-confirmed ...seasonal and pandemic 2009 A/H1N1 (pH1N1) influenza were studied. Plasma concentrations of 13 cytokines/chemokines were measured at presentation and then serially, using cytometric-bead-array with flow-cytometry and ELISA. PBMCs from influenza patients were studied for cytokine/chemokine expression using ex-vivo culture (Whole Blood Assay,±PHA/LPS stimulation). Clinical variables were prospectively recorded and analyzed.
63 pH1N1 and 53 seasonal influenza patients were studied. pH1N1 patients were younger (mean±S.D. 42.8±19.2 vs 70.5±16.7 years), and fewer had comorbidities. Respiratory/cardiovascular complications were common in both groups (71.4% vs 81.1%), although severe pneumonia with hypoxemia (54.0% vs 28.3%) and ICU admissions (25.4% vs 1.9%) were more frequent with pH1N1. Hyperactivation of the proinflammatory cytokines IL-6, CXCL8/IL-8, CCL2/MCP-1 and sTNFR-1 was found in pH1N1 pneumonia (2-15 times normal) and in complicated seasonal influenza, but not in milder pH1N1 infections. The adaptive-immunity (Th1/Th17)-related CXCL10/IP-10, CXCL9/MIG and IL-17A however, were markedly suppressed in severe pH1N1 pneumonia (2-27 times lower than seasonal influenza; P-values<0.01). This pattern was further confirmed with serial measurements. Hypercytokinemia tended to be sustained in pH1N1 pneumonia, associated with a slower viral clearance PCR-negativity: day 3-4, 55% vs 85%; day 6-7, 67% vs 100%. Elevated proinflammatory cytokines, particularly IL-6, predicted ICU admission (adjusted OR 12.6, 95%CI 2.6-61.5, per log(10)unit increase; P = 0.002), and correlated with fever, tachypnoea, deoxygenation, and length-of-stay (Spearman's rho, P-values<0.01) in influenza infections. PBMCs in seasonal influenza patients were activated and expressed cytokines ex vivo (e.g. IL-6, CXCL8/IL-8, CCL2/MCP-1, CXCL10/IP-10, CXCL9/MIG); their 'responsiveness' to stimuli was shown to change dynamically during the illness course.
A hyperactivated proinflammatory, but suppressed adaptive-immunity (Th1/Th17)-related cytokine response pattern was found in severe pH1N1 pneumonia, different from seasonal influenza. Cytokine/immune-dysregulation may be important in its pathogenesis.
This study explored the knowledge, attitude, practice and barriers to prescribe human papillomavirus (HPV) vaccines among private primary care physicians in Hong Kong. A self-administered ...questionnaire survey was conducted by sending letters to doctors who had joined a vaccination program for school girls. From 720 surveys sent, 444 (61.7%) completed questionnaires were returned and analyzed. For knowledge, few responded to questions accurately on the prevalence of cervical HPV (27.9%) and genital wart infection (13.1%) among sexually active young women in Hong Kong, and only 44.4% correctly answered the percentage of cervical cancers caused by HPV. For attitude, most agreed that HPV vaccination should be fully paid by the Government (68.3%) as an important public health strategy. Vaccination against HPV was perceived as more important than those for genital herpes (52.2%) and Chlamydia (50.1%) for adolescent health, and the majority selected adolescents aged 12-14 years as the ideal group for vaccination. Gardasil(®) (30.9%) and Cervarix(®) (28.0%) were almost equally preferred. For practice, the factors influencing the choice of vaccine included strength of vaccine protection (61.1%), long-lasting immunity (56.8%) and good antibody response (55.6%). The most significant barriers to prescribe HPV vaccines consisted of parental refusal due to safety concerns (48.2%), and their practice of advising vaccination was mostly affected by local Governmental recommendations (78.7%). A substantial proportion of physicians had recommended HPV vaccines for their female clients/patients aged 18-26 years for protection of cervical cancer (83.8%) or both cervical cancer and genital warts (85.5%). The knowledge on HPV infection was low among physicians in Hong Kong. Prescription of HPV vaccine was hindered by the perceived parental concerns and was mostly relied on Governmental recommendations. Educational initiatives should be targeted towards both physicians and parents, and the Government should consider full subsidy to enhance vaccine uptake rate.
Purpose - The objective of this paper is to illustrate and examine the different flexibility strategies adopted by supply chain participants as a result of different environmental ...uncertainties.Design methodology approach - An exploratory multi-case study, involving five Chinese companies in the textile and apparel industry, was conducted.Findings - The analysis, based on the supply chain literature, reveals that the unpredictable dynamics of the supply chain can arise from a variety of internal and external sources, including suppliers, operating systems, customers, and competitors. In response to the various environmental uncertainties and risks in the supply chain, four types of flexibility strategy are identified in our case analysis: laggard, conservative, agile, and aggressive. The results also suggest that the adoption of flexibility strategies should match a firm's business environment and that better supply chain responsiveness can be achieved in two ways: by reducing uncertainties and by improving supply chain flexibility.Research limitations implications - The key limitation of the study is that it focuses solely on the textiles and clothing industry, which makes it difficult to generalize the results to other industries. Another difficulty arises from the subjective criteria employed in some constructs, such as the perceived aggressiveness of competition, the predictability of customer demand, and the designations of companies in the proposed strategy categories.Practical implications - The proposed theoretical framework can assist managers in properly diagnosing and deploying supply chain flexibility strategies. The actions identified for promoting supply chain flexibility can also be used to assess the various options for exploiting or acquiring flexibility strategies.Originality value - Expanding on the previous research approach of examining flexibility strategies from the perspective of a single firm, this study draws on the multi-case approach to posit a series of propositions that link the adoption of specific supply chain flexibility strategies to various environmental conditions in a supply chain context and proposes a conceptual framework to illustrate how supply chain responsiveness can be improved in today's volatile market environment.
Web Course Tools (WebCT) have enhanced the ability and motivation of institutes of higher education to support e-learning. In this study, we extended the Technology Acceptance Model to include ...technical support as a precursor and then investigated the role of the extended model in user acceptance of WebCT. Responses from 836 university students were used to test the proposed structural model. The data showed that technical support has a significant direct effect on perceived ease of use and usefulness, while perceived ease of use and usefulness are the dominant factors affecting the attitude of students using WebCT. The results indicate the importance of perceived ease of use and perceived usefulness in mediating the relationship of technical support with attitude and WebCT usage.
The aim of this study was to investigate factors affecting clinical outcomes of adults hospitalised with severe seasonal influenza.
A prospective, observational cohort study was conducted over 24 ...months (2007-2008) in two acute, general hospitals. Consecutive, hospitalised adult patients were recruited and followed once their laboratory diagnosis of influenza A/B was established (based on viral antigen detection and virus isolation from nasopharyngeal aspirates collected per protocol). Outcomes studied included in-hospital death, length of stay and duration of oxygen therapy. Factors affecting outcomes were analysed using multivariate Cox proportional hazards models. Sequencing analysis on the neuraminidase gene was performed for available H1N1 isolates.
754 patients were studied (influenza A, n=539; >75% H3N2). Their mean age was 70+/-18 years; co-morbidities and serious complications were common (61-77%). Supplemental oxygen and ventilatory support was required in 401 (53.2%) and 41 (5.4%) patients, respectively. 39 (5.2%) patients died; pneumonia, respiratory failure and sepsis were the causes. 395 (52%) patients received antiviral (oseltamivir) treatment. Omission of antiviral treatment was associated with delayed presentation or negative antigen detection results. The mortality rate was 4.56 and 7.42 per 1000 patient-days in the treated and untreated patients, respectively; among those with co-morbidities, it was 5.62 and 11.64 per 1000 patient-days, respectively. In multivariate analysis, antiviral use was associated with reduced risk of death (adjusted HR (aHR) 0.27 (95% CI 0.13 to 0.55); p<0.001). Improved survival was observed with treatment started within 4 days from onset. Earlier hospital discharge (aHR 1.28 (95% CI 1.04 to 1.57); p=0.019) and faster discontinuation of oxygen therapy (aHR 1.30 (95% CI 1.01 to 1.69); p=0.043) was associated with early treatment within 2 days. Few (n=15) H1N1 isolates in this cohort had the H275Y mutation.
Antiviral treatment for severe influenza is associated with reduced mortality and improved clinical outcomes.
PDF
