Turning on solid-state phosphorescence of platinum acetylides with aromatic stacking.

Neat solids that phosphoresce under ambient conditions are rare due to aggregation-caused quenching. This communication describes a platinum acetylide (PtPE) that phosphoresces as a solid due to programmed aromatic stacking interactions of pendant groups that prevent intermolecular aggregation.

Directed Polymorphism and Mechanofluorochromism of Conjugated Materials through Weak Non-Covalent Control.

Understanding and manipulating crystal polymorphism can provide novel strategies for materials discovery in organic optoelectronics. In this paper, a series of seven ester-terminated three-ring phenylene ethynylenes (PEs) exhibit structure-dependent polymorphism wherein alkyl chain length modulates the propensity to form violet or green fluorescent solid phases, as well as tunable thermal and mechanofluorochromic (MFC) transitions. These compounds harness "soft" non-covalent control to achieve polymorphism: the electronic substituent effect of the ester groups weakens the fluoroarene-arene (ArF-ArH) interactions that typically direct crystal packing of this class of compounds, increasing competitiveness of other interactions.

Universal temperature dependence, flux extinction, and the role of 3He impurities in superfluid mass transport through solid 4He.

The mass flux, F, carried by as-grown solid (4)He in the range 25.6-26.3 bar rises with falling temperature, and at a concentration-dependent temperature, T(d), the flux decreases sharply within a few mK.

Outcomes of posterior facet versus pedicle screw fixation of circumferential fusion: a cohort study.

Purpose: To compare single-level circumferential spinal fusion using pedicle (n = 27) versus low-profile minimally invasive facet screw (n = 35) posterior instrumentation.

Method: A prospective two-arm cohort study with 5-year outcomes as follow-up was conducted. Assessment included back and leg pain, pain drawing, Oswestry disability index (ODI), pain medication usage, self-assessment of procedure success, and >1-year postoperative lumbar magnetic resonance imaging.

Two-Level Circumferential Lumbar Fusion Comparing Midline and Paraspinal Posterior Approach: 5-Year Interim Outcomes of a Randomized, Blinded, Prospective Study.

Study Design: A prospective randomized and blinded comparative study of 2 patient groups with >5-year follow-up.

Objective: To compare the clinical outcomes and postoperative posterior muscle changes in patients with advanced degenerative disk disease undergoing 2-level circumferential spinal fusion using a posterior midline versus a paraspinal approach.

Summary Of Background Data: Lumbar spinal fusion is often performed using a circumferential (anterior and posterior) technique.