Using one-and two-dimensional NMR spectroscopy applied to 13 C spin-labeled (TMTTF)2AsF6 and (TMTTF)2PF6, we demonstrate the existence of an intermediate charge-ordered phase in the TMTTF family of charge-transfer salts. At ambient temperature, the spectra are characteristic of nuclei in equivalent environments, or molecules. Below a continuous charge-ordering transition temperature Tco, the spectra are explained by assuming there are two inequivalent molecules with unequal electron densities. The absence of an associated magnetic anomaly indicates only the charge degrees of freedom are involved and the lack of evidence for a structural anomaly suggests that charge/lattice coupling is too weak to drive the transition.

These results suggest treatment with fixed buccal orthodontic appliances is associated with decreased periodontal status and increased levels of periodontopathic bacteria when compared to treatment with removable aligners over the 12-month study duration.

As the elderly population is expected to double in number by the year 2030, pelvic organ prolapse will become more prevalent. To allocate resources to the increasing number of female patients who will present to healthcare providers with pelvic organ prolapse, we need a better understanding of its incidence, risk factors, prevalence, natural history, clinical implications, and treatment options. This understanding will not only improve our ability to treat this growing patient population but will also help us develop preventive strategies to ameliorate patients' suffering from this condition.

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The Mott-Hubbard insulator ͑TMTTF͒ 2 PF 6 is well known to have a spin-Peierls ground state at ambient pressure below 18 K, although antiferromagnetic order is stabilized for P . P c 0.9 GPa hydrostatic pressure. Near P c , the transition temperature of both phases appears to be singularly depressed to less than 9 K, consistent with a system where the normal-state physics is controlled by a low-dimensional quantum critical point. [S0031-9007(98)

We present 77 Se nuclear magnetic resonance ͑NMR͒ Knight shift (K) studies in pressurized (TMTSF) 2 PF 6 with a magnetic field aligned along the b axis, perpendicular to the conducting chains but parallel to the conducting plane. On cooling deep into the superconducting state, no observable change in K from both spin echo and free induction decay signal was found. This strongly suggests triplet superconductivity in (TMTSF) 2 PF 6 .

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