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Further improving the accuracy of fetal foot length to confirm gestational duration: Additional data.
Terahertz quantum plasmonics at nanoscales and angstrom scales
Through the manipulation of metallic structures, light-matter interaction can enter into the realm of quantum mechanics. For example, intense terahertz pulses illuminating a metallic nanotip can promote terahertz field-driven electron tunneling to generate enormous electron emission currents in a subpicosecond time scale. By decreasing the dimension of the metallic structures down to the nanoscale and angstrom scale, one can obtain a strong field enhancement of the incoming terahertz field to achieve atomic field strength of the order of V/nm, driving electrons in the metal into tunneling regime by overcoming the potential barrier. Therefore, designing and optimizing the metal structure for high field enhancement are an essential step for studying the quantum phenomena with terahertz light. In this review, we present several types of metallic structures that can enhance the coupling of incoming terahertz pulses with the metals, leading to a strong modification of the potential barriers by the terahertz electric fields. Extreme nonlinear responses are expected, providing opportunities for the terahertz light for the strong light-matter interaction. Starting from a brief review about the terahertz field enhancement on the metallic structures, a few examples including metallic tips, dipole antenna, and metal nanogaps are introduced for boosting the quantum phenomena. The emerging techniques to control the electron tunneling driven by the terahertz pulse have a direct impact on the ultrafast science and on the realization of next-generation quantum devices
Organising case management for people with complex long-term conditions: learn from the experiences of Case Managers and Community Matrons
Case Management (CM) requires a structured and systematic approach in order to be an effective tool for managing a growing population with complex long-term conditions (LTCs). This study aims to characterise, describe and explain the complex organising work of CM in relation to the roles of community matron (CMN) and case manager (CMR), and their training and service arrangement in UK localities through Translational Mobilisation theory (TMT). A qualitative descriptive research approach was used including semi-structured interviews and framework analysis. From interviews with 32 CMNs and CMRs, the study discovered that these roles enable the realising of political aims with regards to the reduction of service usages and improved quality of life for people living with complex LTCs. Their proactive, holistic and individualised care approach in these roles was perceived to be distinctive compared to other health care professionals, but these were not well understood and supported. This was a barrier to effective CM. Secondly, CMNs found that their education programmes on advanced clinical skills improved their knowledge of general illnesses but provided insufficient clinical practice and mentorship for treating common LTCs. In comparison, CMR’s self-directed their learning of common LTCs based on inconsistent organisational funding and course availability. Thirdly, the participants working in different service arrangements in rural and urban areas contributed different benefits and barriers in delivering their role. From the findings, this study proposed a standardised CMN and CMR training based on their common learning needs. Their role requires detailed practice guidelines and a practice-based CM approach with detailed plans to organise CM. Thus, a more standardised and systematic approach to CM is indicated by this study. Therefore, this approach needs extensive research
Strategic Asset Seeking and Innovation Performance: The Role of Innovation Capabilities and Host Country Institutions
fals
Flux Noise in MgB2 Thin Films
We have performed flux noise and AC-susceptibility measurements on two 400 nm
thick MgB films. Both measurement techniques give information about the
vortex dynamics in the sample, and hence the superconducting transition, and
can be linked to each other through the fluctuation-dissipation-theorem. The
transition widths for the two films are 0.3 and 0.8 K, respectively, and the
transitions show a multi step-like behavior in the AC-susceptibility
measurements. The same phenomenon is observed in the flux noise measurements
through a change in the frequency dependence of the spectral density at each
step in the transition. The results are discussed and interpreted in terms of
vortices carrying an arbitrary fraction of a flux quantum as well as in terms
of different macroscopic regions in the films having slightly different
compositions, and hence, different critical temperatures.Comment: 8 pages, 4 figures, conference contribution to "Fluctuations and
Noise", Santa Fe, New mexico 1-4 june 200
Antioxidative and Antimutagenic Activities of 70% Ethanolic Extracts from Four Fungal Mycelia-Fermented Specialty Rices
The health-promoting potential of 70% ethanolic extracts of 4 rice varieties fermented with Monascus ruber, Phellinus linteus, Cordyceps sinensis and Agaricus blazei was evaluated mainly focusing on their antioxidative and antimutagenic capacities based on the following parameters: phenolic compound and phytic acid content; inhibitory activity on lipid peroxidation; scavenging activity on DPPH radical; suppressing ability on mitomycin C-induced mutagenesis in E. coli cells; and protective effect on 4-nitroquinoline oxide-triggered DNA lesion in V79 hamster cells. The fermented rice extracts were superior in overall health-promoting parameters compared to the source material. The higher antimutagenic activity of the fermented rice extracts might be in part caused by a larger amount of antioxidant constituents such as phenolic compounds or phytic acid. Of the fungal species, Monascus ruber was found to impart a marked increase in both the antioxidative and antimutagenic abilities to the source material. The current study suggests a possibility that such fermented rice may contribute to the prevention of lifestyle-related diseases such as cancer through a daily intake of rice-based diets
Recent advances in synchrotron X-ray studies of the atomic structures of metal alloys in liquid state
Research into the atomic structures of metal materials in the liquid state, their dynamic evolution versus temperature until the onset of crystal nucleation has been a central research topic in condensed matter physics and materials science for well over a century. However, research and basic understanding of the atomic structures of liquid metals are far less than those in the solid state of the samecompositions. This review serves as a condensed collection of the most important research literature published so far in this field, providing a critical and focused review of the historical research development and progress in this field since the 1920s. In particular, the development of powerful synchrotron X-ray sources and the associated experimental techniques and sample environments for studying in-situ the atomic structures of different metallic systems. The key findings made in numerous pure metals and metallic alloysystems are critically reviewed and discussed with the focus on the results and new understandings of structural heterogeneities found inside a bulk liquids, at the liquid surface of liquids, and or at liquid-solid interfaces. The possible future directions of research and development on the most advanced experimental and modelling techniques are envisaged and briefly discussed as well
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