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91.
The ability of ultraviolet resonance Raman spectroscopy (UVRRS) to determine structural, environmental, and analytical information concerning low-concentration aqueous biomolecules makes it a powerful bioanalytical and biophysical technique. Unfortunately, its utility has been limited by experimental requirements that preclude in situ or in vivo studies in most cases. We have developed the first high-performance fiber-optic probes suitable for long-term use in pulsed UVRRS applications in the deep- UV (DUV, 205-250 nm). The probes incorporate recently developed improved ultraviolet (IUV) fibers that do not exhibit the rapid solarization and throughput decay that previously hampered the use of optical fibers for delivering pulsed, DUV light. A novel 90 degrees mirrored collection geometry is used to overcome the inner-filtering effects that plague flush-probe geometries. The IUV fibers are characterized with respect to their efficacy at transmitting pulsed, DUV laser light, and prototype probes are used to obtain pulsed UVRRS data of aromatic amino acids, proteins, and hormones at low concentrations with 205-240-nm pulsed excitation. Efficient probe geometries and fabrication methods are presented. The performance of the probes in examining resonance-enhanced Raman signals from absorbing chromophores is investigated, and the optimal excitation wavelength is shown to be significantly red-shifted from the maximum of the resonance Raman enhancement profile. Generally applicable procedures for determining optimal experimental conditions are also introduced. 相似文献
92.
Presents an editorial on the 50th Anniversary Issue of The American Psychologist by the CEO and Executive Vice President of the American Psychological Association. An overview of changes to the journal and the developments in electronic communications pare presented, and the implications for international exchange in scholarly publishing are discussed. (0 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
A growing number of patients are recognised to have chronic kidney disease (CKD). However, only a minority will progress to end-stage renal disease requiring dialysis or transplantation. Currently available diagnostic and staging tools frequently fail to identify those at higher risk of progression or death. Furthermore within specific disease entities there are shortcomings in the prediction of the need for therapeutic interventions or the response to different forms of therapy. Kidney and urine proteomic biomarkers are considered as promising diagnostic tools to predict CKD progression early in diabetic nephropathy, facilitating timely and selective intervention that may reduce the related health-care expenditures. However, independent groups have not validated these findings and the technique is not currently available for routine clinical care. Furthermore, there are gaps in our understanding of predictors of progression or need for therapy in non-diabetic CKD. Presumably, a combination of tissue and urine biomarkers will be more informative than individual markers. This review identifies clinical questions in need of an answer, summarises current information on proteomic biomarkers and CKD, and describes the European Kidney and Urine Proteomics initiative that has been launched to carry out a clinical study aimed at identifying urinary proteomic biomarkers distinguishing between fast and slow progressors among patients with biopsy-proven primary glomerulopathies. 相似文献
94.
Barbara A. Kitchenham Pearl Brereton Mark Turner Mahmood K. Niazi Stephen Linkman Rialette Pretorius David Budgen 《Empirical Software Engineering》2010,15(6):618-653
Systematic literature reviews (SLRs) are a major tool for supporting evidence-based software engineering. Adapting the procedures
involved in such a review to meet the needs of software engineering and its literature remains an ongoing process. As part
of this process of refinement, we undertook two case studies which aimed 1) to compare the use of targeted manual searches
with broad automated searches and 2) to compare different methods of reaching a consensus on quality. For Case 1, we compared
a tertiary study of systematic literature reviews published between January 1, 2004 and June 30, 2007 which used a manual
search of selected journals and conferences and a replication of that study based on a broad automated search. We found that
broad automated searches find more studies than manual restricted searches, but they may be of poor quality. Researchers undertaking
SLRs may be justified in using targeted manual searches if they intend to omit low quality papers, or they are assessing research
trends in research methodologies. For Case 2, we analyzed the process used to evaluate the quality of SLRs. We conclude that
if quality evaluation of primary studies is a critical component of a specific SLR, assessments should be based on three independent
evaluators incorporating at least two rounds of discussion. 相似文献
95.
Examining knowledge contribution from the perspective of an online identity in blogging communities 总被引:1,自引:0,他引:1
Knowledge contribution is one of the essential factors behind the success of blogging communities (BCs). This research studies knowledge contribution behavior in a BC from the perspective of knowledge contributors and their characteristics using the lens of social identity theory. Social identity theory asserts that individuals are fundamentally motivated to present or communicate their identities in everyday social life through behavior. A similar line of reasoning can be used to argue that members of a BC would also be motivated to communicate their online identities through their behavior, that is, through knowledge contribution in the BC. Specifically, this study conceptualized the online identity and examined the effects of its personal (online kindness, online social skills, and online creativity) and social aspects (BC involvement) on knowledge contribution. The data was collected using an online survey from the members of Cyworld, a popular BC in South Korea and a few other countries (members from South Korea were included in this study). The results indicate that both the personal and social aspects of online identity and their interactions significantly influenced knowledge contribution. Based on the findings, this study offers suggestions to organizers of BCs to enhance the knowledge contribution from their members. 相似文献
96.
In non-invasive thermal diagnostics, accurate correlations between the thermal image at skin surface and interior human physiology are desired. In this work, an estimation methodology to determine unknown geometrical parameters of an embedded tumor is proposed. We define a functional that represents the mismatch between a measured experimental temperature profile, which may be obtained by infrared thermography on the skin surface, and the solution of an appropriate boundary problem. This functional is related to the geometrical parameters through the solution of the boundary problem, in such a way that finding the minimum of this functional form also means finding the unknown geometrical parameters of the embedded tumor. Sensitivity analysis techniques coupled with the adjoint method were considered to compute the shape derivative of the functional. Then, a nonmonotone spectral projected gradient method was implemented to solve the optimization problem of finding the optimal geometric parameters. 相似文献
97.
This laboratory study examined the possibility of using a car seat instrumented with a tactile display to communicate directional information to a driver. A car seat fitted with an 8 × 8 matrix of vibrators embedded in the seat pan was used to code eight different directions. Localization response time and angular accuracy were examined as a function of stimulus direction, presence of a tactile attention cue, temporal pattern, stimulus layout, age, and gender. The mean absolute angular error was 23°, and both localization accuracy and response times were superior for the back left, backward, and back right directions. Of the various temporal pattern/attention cue combinations examined, results favored the relatively fast patterns consisting of vibration bursts of 125 or 250 ms without a centrally located attention cue over 500 ms bursts that were preceded by an attention cue. Observed age and gender effects were relatively modest, suggesting that using tactile cueing to communicate direction is effective across a wide range of users. In addition, the tactile stimulus was detected by more than 90% of the participants under surprise trial conditions. Overall, these results indicate that the tactile chair provides a promising and robust method of providing directional information. 相似文献
98.
Matthew R. Graham Author Vitae Author Vitae Raymond A. de Callafon Author Vitae 《Automatica》2009,45(6):1489-1496
This paper introduces an alternative formulation of the Kalman-Yakubovich-Popov (KYP) Lemma, relating an infinite dimensional Frequency Domain Inequality (FDI) to a pair of finite dimensional Linear Matrix Inequalities (LMI). It is shown that this new formulation encompasses previous generalizations of the KYP Lemma which hold in the case the coefficient matrix of the FDI does not depend on frequency. In addition, it allows the coefficient matrix of the frequency domain inequality to vary affinely with the frequency parameter. One application of this results is illustrated in an example of computing upper bounds to the structured singular value with frequency-dependent scalings. 相似文献
99.
Abdullah Azfar Kim-Kwang Raymond Choo Lin Liu 《Multimedia Tools and Applications》2017,76(3):3313-3341
Android productivity apps have provided the facility of having a constantly accessible and productive workforce to the information and work capabilities needed by the users. With hundreds of productivity apps available in the Android app market, it is necessary to develop a taxonomy for the forensic investigators and the end users to allow them to know what personal data remnants are available from the productivity apps. In this paper, 30 popular Android productivity apps were examined. A logical extraction of the Android phone was collected by using a well-known mobile forensic tool- XRY to extract various information of forensic interest such as user email ID and list of tasks. Based on the findings, a two-dimensional taxonomy of the forensic artefacts of the productivity apps is proposed with the app categories in one dimension and the classes of artefacts in the other dimension. The artefacts identified in the study of the apps are summarised using the taxonomy. In addition, a comparison with the existing forensic taxonomies of different categories of Android apps is provided to facilitate timely collection and analysis of evidentiary materials from mobile devices. 相似文献
100.
Yu-Chen Hu Kim-Kwang Raymond Choo Wu-Lin Chen 《Multimedia Tools and Applications》2017,76(14):15435-15463
To ensure the integrity of images compressed using block truncation coding (BTC), a tamper detection and image recovery scheme is proposed in this paper. In this scheme, the size of the authentication data can be adaptively selected according to the user’s requirement. The authentication data is embedded in the value differences of the quantization levels in each BTC-compressed image block. Multiple copies of the recovery data are embedded into the bit maps of the smooth blocks. Experimental results show that the proposed scheme performs well in terms of detection precision and the embedded image quality. Meanwhile, the tampered areas can be roughly recovered by using the proposed scheme. 相似文献