Finland Love Song

https://digitalcommons.library.umaine.edu/mmb-vp/5885/thumbnail.jp

Accurate measurement of ^{13}C - ^{15}N distances with solid-state NMR

Solid-state NMR technique for measureing distances between hetero-nuclei in static powder samples is described. It is based on a two-dimensional single-echo scheme enhanced with adiabatic cross-polarization. As an example, the results for intra-molecular distances in $\alpha$-crystalline form of glycine are presented. The measured NMR distances ^13 C(2) - ^15 N and ^13 C(1) - ^15 N are 1.496 $\pm$ 0.002 \AA and 2.50 $\pm$ 0.02 \AA, respectively.Comment: 12 page

Electron Self-Energy of High Temperature Superconductors as Revealed by Angle Resolved Photoemission

In this paper, we review some of the work our group has done in the past few years to obtain the electron self-energy of high temperature superconductors by analysis of angle-resolved photoemission data. We focus on three examples which have revealed: (1) a d-wave superconducting gap, (2) a collective mode in the superconducting state, and (3) pairing correlations in the pseudogap phase. In each case, although a novel result is obtained which captures the essense of the data, the conventional physics used leads to an incomplete picture. This indicates that new physics needs to be developed to obtain a proper understanding of these materials.Comment: 5 pages, revtex, 3 encapsulated postscript figures, SNS97 proceeding

The de Haas-van Alphen effect in Kondo systems with crystalline electric field

The effective mass probed by the de Haas-van Alphen oscillations is studied for a model Ce system under magnetic field higher than the Kondo energy. In the mean-field theory, the mass enhancement per Ce ion in the periodic system is identical with that in the dilute system. With decreasing magnetic field, the effective mass tends to diverge corresponding to a formation of the Kondo ground state. The effective mass can be very different between up and down spins depending on the nature of the 4f wave functions.Comment: 2 pages, 1 figure, ICM2006 proceeding

Uso de RMN no Estado Estacionário para Aumento de Sensibilidade de Análises Químicas.

bitstream/CNPDIA/10489/1/CT37_2000.pd

Metodologia de medida da difusividade térmica por RMN-CWFP.

bitstream/CNPDIA-2009-09/11832/1/CT72_2006.pd

Screening effects in the electron-optical phonon interaction

We show that recently reported unusual hardening of optical phonons renormalized by the electron-phonon interaction is due to the neglect of screening effects. When the electron-ion interaction is properly screened optical phonons soften in three dimension. It is important that for short-wavelength optical phonons screening is static while for long-wavelength optical phonons screening is dynamic. In two-dimensional and one-dimensional cases due to crossing of the nonperturbed optical mode with gapless plasmons the spectrum of renormalized optical phonon-plasmon mode shows split momentum dependence.Comment: 7 page

Effect of electron-phonon interaction on the shift and attenuation of optical phonons

Using the Boltzmann equation for electrons in metals, we show that the optical phonons soften and have a dispersion due to screening in agreement with the results reported recently [M. Reizer, Phys. Rev. B {\bf 61}, 40 (2000)]. Additional phonon damping and frequency shift arise when the electron--phonon interaction is properly included.Comment: 4 pages, late

Outcomes of external and endonasal dacryocystorhinostomy according to a modified Lacrimal Symptom Questionnaire (Lac-Q)

Background: Nasolacrimal duct obstruction is usually treated using endoscopic or external dacryocystorhinostomy (DCR). The anatomic outcomes of both the endoscopic and external approaches are considered excellent. However, anatomic success does not translate into patient satisfaction. The current study assessed pre- and postoperative lacrimal problems using the symptom-based Lacrimal Symptom Questionnaire (Lac-Q) and investigated patient satisfaction depending on the choice of surgical technique. Methods: A total of 112 eligible patients with lacrimal problems treated using external or endonasal DCR at the ophthalmology and ear, nose, and throat clinics at Skane University Hospital, Sweden, over a four-year period, were enrolled in this retrospective study. Patients were considered eligible if they experienced preoperative epiphora and had lacrimal duct stenosis. They were offered treatment using either external or endonasal DCR and were allowed to freely choose the technique. Exclusion criteria consisted of previous ipsilateral DCR, congenital NLDO, age < 18 years, presence of cancer, previous orbital trauma, or noncompliance with postoperative follow-up. After surgery, the patients were sent the Lac-Q to evaluate their lacrimal symptoms pre- and postoperatively. Complementary questions were added pertaining to the operative scar and the patients’ overall satisfaction with the operation. Results: In total, 67 (60%) patients with ages ranging from 18 to 88 years completed the questionnaire, 33 (49%) of whom underwent external DCR and 34 (51%) endonasal DCR. Of the 67 respondents, 51 (76%) were women and 16 (24%) were men. Patients scored preoperative lacrimal problems highly on the Lac-Q, reporting both symptomatic and social problems due to epiphora. Following surgery, the group that underwent external DCR  remained home from work for 2 – 14 days (median, 3.5 days). However, 17 (52%) were retired. After the endonasal DCR, the patients remained home for 0 – 7 days (median, 2 days). Most patients were satisfied after DCR surgery, with both techniques significantly improving total, lacrimal symptom, and social impact scores (all P < 0.001). No differences in postoperative satisfaction were observed between the external DCR and endonasal DCR groups (P > 0.05). A small number of patients expressed scar-related concerns after external DCR. Conclusions: The patients perceived lacrimal problems as a significant symptomatic and social burden. Postoperative satisfaction and symptom relief were good regardless of the surgical approach. Further prospective studies assessing patient satisfaction and its correlation with anatomical and functional success rates after external and endonasal DCR could provide robust, practical, real-world implications