Integral equation formulation of the spinless Salpeter equation

The spinless Salpeter equation presents a rather particular differential operator. In this paper we rewrite this equation into integral and integro-differential equations. This kind of equations are well known and can be more easily handled. We also present some analytical results concerning the spinless Salpeter equation and the action of the square-root operator.Comment: 13 pages, no figure. ReVTeX file. To appear in J. MATH. PHY

Analytical Solution of the Relativistic Coulomb Problem with a Hard-Core Interaction for a One-Dimensional Spinless Salpeter Equation

In this paper, we construct an analytical solution of the one-dimensional spinless Salpeter equation with a Coulomb potential supplemented by a hard core interaction, which keeps the particle in the x positive region

Construction of an artificial cell membrane anchor using DARC as a fitting for artificial extracellular functionalities of eukaryotic cells

The need to functionalize cell membranes in a directed way for specific applications as single cell arrays or to force close cell-to-cell contact for artificial intercellular interaction and/or induction concerning stem cell manipulation or in general to have a tool for membrane and cell surface-associated processes, we envisaged a neutral inactive membrane anchor for extracellular entities to facillitate the above mentioned functionalities

Chemically synthesized zinc finger molecules as nano-addressable probes for double-stranded DNAs

Our experiments describe an alternative method of dsDNA recognition using zinc finger (ZF) molecules which bind DNA specifically and with high affinity. Our aim was to develop zinc finger probes which are able to bind to dsDNA molecules at predetermined sites. In our basic approach we used pairs of complementary oligonucleotides to form dsDNAs, containing one of the three SP1-transcription factor motifs as a zinc finger recognition site. Two zinc finger probes of the SP1 motif were chemically synthesized and modified with a Dy-633 fluorophore. The SP1 peptides were folded into functional zinc fingers using zinc chloride. The addressable dsDNAs were immobilized on optical fibres, and the kinetics and binding rates of the artificial zinc finger probes were measured by a fluorescence detecting device (photomultiplying tube). The two zinc fingers and their corresponding DNA recognition sites served as specific probes and controls for the matching site and vice versa. Our experiments showed that a variety of dsDNA-binding probes may be created by modification of the amino acid sequence of natural zinc finger proteins. Our findings offer an alternative approach of addressing dsDNA molecules, for example for use in a nanoarray device

Validation and Generalizability of Preoperative PROMIS Scores to Predict Postoperative Success in Foot and Ankle Patients

Background: A recent publication reported preoperative Patient-Reported Outcomes Measurement Instrumentation System (PROMIS) scores to be highly predictive in identifying patients who would and would not benefit from foot and ankle surgery. Their applicability to other patient populations is unknown. The aim of this study was to assess the validation and generalizability of previously published preoperative PROMIS physical function (PF) and pain interference (PI) threshold t scores as predictors of postoperative clinically meaningful improvement in foot and ankle patients from a geographically unique patient population. Methods: Prospective PROMIS PF and PI scores of consecutive patient visits to a tertiary foot and ankle clinic were obtained between January 2014 and November 2016. Patients undergoing elective foot and ankle surgery were identified and PROMIS values obtained at initial and follow-up visits (average, 7.9 months). Analysis of variance was used to assess differences in PROMIS scores before and after surgery. The distributive method was used to estimate a minimal clinically important difference (MCID). Receiver operating characteristic curve analysis was used to determine thresholds for achieving and failing to achieve MCID. To assess the validity and generalizability of these threshold values, they were compared with previously published threshold values for accuracy using likelihood ratios and pre- and posttest probabilities, and the percentages of patients identified as achieving and failing to achieve MCID were evaluated using χ2 analysis. Results: There were significant improvements in PF (P \u3c .001) and PI (P \u3c .001) after surgery. The area under the curve for PF (0.77) was significant (P \u3c .01), and the thresholds for achieving MCID and not achieving MCID were similar to those in the prior study. A significant proportion of patients (88.9%) identified as not likely to achieve MCID failed to achieve MCID (P = .03). A significant proportion of patients (84.2%) identified as likely to achieve MCID did achieve MCID (P \u3c .01). The area under the curve for PROMIS PI was not significant. Conclusions: PROMIS PF threshold scores from published data were successful in classifying patients from a different patient and geographic population who would improve with surgery. If functional improvement is the goal, these thresholds could be used to help identify patients who will benefit from surgery and, most important, those who will not, adding value to foot and ankle health care. Level of evidence: Level II, Prospective Comparative Stud

Large Possible retardation effects of quark confinement on the meson spectrum II

We present the results of a study of heavy-light-quark bound states in the context of the reduced Bethe-Salpeter equation with relativistic vector and scalar interactions. We find that satisfactory fits may also be obtained when the retarded effect of the quark-antiquark interaction is concerned.Comment: 11 pages, RevTex, to appear in PR

Probabilistic Reconstruction in Compressed Sensing: Algorithms, Phase Diagrams, and Threshold Achieving Matrices

Compressed sensing is a signal processing method that acquires data directly in a compressed form. This allows one to make less measurements than what was considered necessary to record a signal, enabling faster or more precise measurement protocols in a wide range of applications. Using an interdisciplinary approach, we have recently proposed in [arXiv:1109.4424] a strategy that allows compressed sensing to be performed at acquisition rates approaching to the theoretical optimal limits. In this paper, we give a more thorough presentation of our approach, and introduce many new results. We present the probabilistic approach to reconstruction and discuss its optimality and robustness. We detail the derivation of the message passing algorithm for reconstruction and expectation max- imization learning of signal-model parameters. We further develop the asymptotic analysis of the corresponding phase diagrams with and without measurement noise, for different distribution of signals, and discuss the best possible reconstruction performances regardless of the algorithm. We also present new efficient seeding matrices, test them on synthetic data and analyze their performance asymptotically.Comment: 42 pages, 37 figures, 3 appendixe