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51.
Richard F. Patterson Jeff Connor Jeannette Kline 《Central European Journal of Mathematics》2008,6(3):488-496
The notion of oscillation for ordinary sequences was presented by Hurwitz in 1930. Using this notion Agnew and Hurwitz presented
regular matrix characterization of the resulting sequence space. The primary goal of this article is to extend this definition
to double sequences, which grants us the following definition: the double oscillation of a double sequence of real or complex
number is given P-lim sup(m,n)→∞;(α,β)→∞|S
m,n
-S
α,β
|. Using this concept a matrix characterization of double oscillation sequence space is presented. Other implication and variation
shall also be presented.
相似文献
52.
Silvin P. Knight Louise Newman John D. OConnor James Davis Rose Anne Kenny Roman Romero-Ortuno 《Entropy (Basel, Switzerland)》2021,23(1)
In this cross-sectional study, the relationship between noninvasively measured neurocardiovascular signal entropy and physical frailty was explored in a sample of community-dwelling older adults from The Irish Longitudinal Study on Ageing (TILDA). The hypothesis under investigation was that dysfunction in the neurovascular and cardiovascular systems, as quantified by short-length signal complexity during a lying-to-stand test (active stand), could provide a marker for frailty. Frailty status (i.e., “non-frail”, “pre-frail”, and “frail”) was based on Fried’s criteria (i.e., exhaustion, unexplained weight loss, weakness, slowness, and low physical activity). Approximate entropy (ApEn) and sample entropy (SampEn) were calculated during resting (lying down), active standing, and recovery phases. There was continuously measured blood pressure/heart rate data from 2645 individuals (53.0% female) and frontal lobe tissue oxygenation data from 2225 participants (52.3% female); both samples had a mean (SD) age of 64.3 (7.7) years. Results revealed statistically significant associations between neurocardiovascular signal entropy and frailty status. Entropy differences between non-frail and pre-frail/frail were greater during resting state compared with standing and recovery phases. Compared with ApEn, SampEn seemed to have better discriminating power between non-frail and pre-frail/frail individuals. The quantification of entropy in short length neurocardiovascular signals could provide a clinically useful marker of the multiple physiological dysregulations that underlie physical frailty. 相似文献
53.
Wai Yi Kelly Chan T. W. Dominic Chan Peter B. O’Connor 《Journal of the American Society for Mass Spectrometry》2010,21(6):1012-1015
Electron-transfer dissociation (ETD) with supplemental activation of the doubly charged deamidated tryptic digested peptide
ions allows differentiation of isoaspartic acid and aspartic acid residues using the c + 57 or z • − 57 peaks. The diagnostic peak clearly localizes and characterizes the isoaspartic acid residue. Supplemental activation
in ETD of the doubly charged peptide ions involves resonant excitation of the charge reduced precursor radical cations and
leads to further dissociation, including extra backbone cleavages and secondary fragmentation. Supplemental activation is
essential to obtain a high quality ETD spectrum (especially for doubly charged peptide ions) with sequence information. Unfortunately,
the low-resolution of the ion trap mass spectrometer makes detection of the diagnostic peak, [M-60], for the aspartic acid
residue difficult due to interference with side-chain loss from arginine and glutamic acid residues. 相似文献
54.
Abe F Amidei D Apollinari G Ascoli G Atac M Auchincloss P Baden AR Barbaro-Galtieri A Barnes VE Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge P Bertolucci S Bhadra S Binkley M Blair R Blocker C Bofill J Booth AW Brandenburg G Brown D Byon A Byrum KL Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Cervelli F Chadwick K Chapin T Chiarelli G Chinowsky W Cihangir S Cline D Connor D Contreras M Cooper J Cordelli M Curatolo M Day C DelFabbro R 《Physical review D: Particles and fields》1990,41(5):1722-1725
55.
Abe F Amidei D Apollinari G Ascoli G Atac M Auchincloss P Baden AR Barbaro-Galtieri A Barnes VE Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge P Bertolucci S Bhadra S Binkley M Blair R Blocker C Bofill J Booth AW Brandenburg G Brown D Byon A Byrum KL Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Cervelli F Chadwick K Chapin T Chiarelli G Chinowsky W Cihangir S Cline D Connor D Contreras M Cooper J Cordelli M Curatolo M Day C DelFabbro R 《Physical review letters》1989,62(26):3020-3023
56.
A two step sequence converts certain cyclic enones to fused methylenecyclopentanes using the annulation reagent 2-chloromethyl-3-trimethylsilylpropene. 相似文献
57.
Z. Zhong D. Chapman D. Connor A. Dilmanian N. Gmur M. Hasnah 《Synchrotron Radiation News》2013,26(6):27-34
The APS hosted a two-day workshop on Catalysis Research at the APS on September 12-13, 2005. The goal of the workshop was to evaluate current catalysis-related research at the APS and to plan future directions. The outcome of the meeting will be a report with recommendations to promote new, and support current, catalysis research at the APS. The workshop was attended by 82 participants representing industry, national laboratories, and universities. 相似文献
58.
59.
Given densities μ and v, we characterize nonnegative matrices T such that the μ-statistical core of x equals the v-statistical core of Tx for every real-valued bounded sequence. 相似文献
60.
Cailin O’Connor 《The Journal of mathematical sociology》2017,41(3):155-171
Why do minority groups tend to be discriminated against when it comes to situations of bargaining and resource division? In this article, I explore an explanation for this disadvantage that appeals solely to the dynamics of social interaction between minority and majority groups—the cultural Red King effect (Bruner, 2017). As I show, in agent-based models of bargaining between groups, the minority group will tend to get less as a direct result of the fact that they frequently interact with majority group members, while majority group members meet them only rarely. This effect is strengthened by certain psychological phenomenon—risk aversion and in-group preference—is robust on network models, and is strengthened in cases where preexisting norms are discriminatory. I will also discuss how this effect unifies previous results on the impacts of institutional memory on bargaining between groups. 相似文献