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KEY WORDSPoly(butylene succinate-co-butylene carbonate) / Poly(L-lactic acid) / Crystalline Polymer Blends / Interpenetrated Spherulites / The numbers of the studies on miscible pairs of crystalline polymers with different chemical structures are still restricted compared with those with similar chemical structures. 1-10 The differences of the melting temperatures T m of the components are usually 100 • C in the former systems. In these cases, the higher-T m component crystallizes first in the crystallization process and the other component then crystallizes in spatially constrained amorphous regions inside the spherulites.In contrast, when T m s of both components are close enough to each other, the blends exhibit simultaneous spherulitic growth. The spherulites in poly(butylene succinate)/poly(vinylidene chloride-co-vinyl chloride) (PBSU/PVDCVC) blends, whose T m difference is about 35 • C, grow simultaneously. These blends were found to show interpenetrated spherulites (IPS). 11,12 They are characterized by the penetration of PBSU lamellae into PVDCVC spherulites since the lamellar population density in a spherulite is larger for PBSU than for PVDCVC. 13,14 They are expected to have various unique physical characteristics.The reports on the blend systems that show IPS are very few. This is partly because miscible crystalline polymers rarely have close T m s. Our group has been searching polymer blends that show IPS.Poly(butylene succinate-co-butylene carbonate) (PEC) and poly(L-lactic acid) (PLLA) are polyesters whose T m s are close to each other (106 • C and 140 • C, respectively). If they are miscible, they possibly crystallize simultaneously and show IPS. Furthermore, since both PEC and PLLA are biodegradable, PEC/PLLA blends can be ecological crystalline polymer blends.The purposes of this paper are to show miscibility of PEC/PLLA by differential scanning calorimetry (DSC), to study the crystallization behavior by polarizing optical microscopy (POM), and to investigate the possibility of IPS. PEC/PLLA blends were prepared with mutual solvent chloroform at room temperature. The solution was cast on glass plates and then the solvent was removed at room temperature to make thin films for POM observation. For DSC, the solution was dried for a week and then in a vacuum for three days to remove the solvent from the bulky samples.The glass transition temperature T g was determined by DSC (TA Instruments DSC 2910). Samples were heated to 170 • C for 5 min, quenched to −100 • C using liquid nitrogen, kept for 5 min, and heated at 10 • C min −1 . The value of T g was determined as the temperature of the half-height of the step transition.To study the morphology of the blends and the radial spherulitic growth rates G of PEC and PLLA, we used POM (Olympus BHP-P) equipped with a first order retardation plate and a temperature controller (Linkam TH-600). Samples were premelted at 170 • C for 3 min and then quenched to the crystallization temperature T c . RESULTS AND DISCUSSIONTo confirm the miscibility of the PEC/PLL...

Context Daily growth hormone (GH) injections can be burdensome for patients and carers. Somapacitan is a long-acting, reversible albumin-binding GH derivative in development for once-weekly administration in patients with growth hormone deficiency (GHD). Objective The objective of this study is to evaluate the efficacy, safety, and tolerability of once-weekly somapacitan vs once-daily GH. Design REAL 3 is a multicenter, randomized, controlled, double-blind (somapacitan doses), phase 2 study with a 26-week main and 26-week extension phase (NCT02616562). Setting This study took place at 29 sites in 11 countries. Patients Fifty-nine GH treatment-naive prepubertal children with GHD were randomly assigned; 58 completed the trial. Interventions Interventions comprised 3 somapacitan doses (0.04 [n = 16], 0.08 [n = 15], or 0.16 mg/kg/wk [n = 14]) and daily GH (0.034 mg/kg/d [n = 14]), administered subcutaneously. Main Outcome Measures The primary end point was height velocity (HV) at week 26. Secondary efficacy end points included HV SD score (SDS) and insulin-like growth factor-I (IGF-I) SDS. Results At week 26, mean (SD) annualized HV for the somapacitan groups was 8.0 (2.0), 10.9 (1.9), and 12.9 (3.5) cm/year, respectively, vs 11.4 (3.3) cm/year for daily GH; estimated treatment difference (somapacitan 0.16 mg/kg/week—daily GH): 1.7 [95% CI –0.2 to 3.6] cm/year. HV was sustained at week 52, and significantly greater with somapacitan 0.16 mg/kg/week vs daily GH. Mean (SD) change from baseline in HV SDS at week 52 was 4.72 (2.79), 6.14 (3.36), and 8.60 (3.15) for the somapacitan groups, respectively, vs 7.41 (4.08) for daily GH. Model-derived mean (SD) IGF-I SDS for the somapacitan groups was −1.62 (0.86), −1.09 (0.78), and 0.31 (1.06), respectively, vs −0.40 (1.50) observed for daily GH. Safety and tolerability were consistent with the profile of daily GH. Conclusions In children with GHD, once-weekly somapacitan 0.16 mg/kg/week provided the closest efficacy match with similar safety and tolerability to daily GH after 26 and 52 weeks of treatment. A short visual summary of our work is available (1).

We have investigated monolayer and multilayer islands of La 2 @C 80 and La@C 82 molecules grown on a hydrogen-terminated Si(100)-2 × 1 surfaces by ultrahigh vacuum scanning tunneling microscopy. The observed La 2 @C 80 molecule has a spherical shape, consistent with a recent result by synchrotron X-ray measurements. The energy gap for the La 2 @C 80 multilayer islands is measured to be 1.3−1.5 eV, whereas that for La@C 82 is 0.5 eV, indicating that the I h cage of the La 2 @C 80 molecule is highly stabilized by an electron transfer from the encaged La atoms.

We used a pulse-injection method to fix π-conjugated poly(3-hexylthiophene) (P3HT) molecules onto H-terminated Si(100) surfaces. Isolated molecules of P3HT were observed by scanning tunneling microscopy. The P3HT molecules comprised an almost all-trans conformation, reflecting the rigid feature of molecular chains. By quenching the substrate at 135 K, residual solvent molecules were observed. We could control the surface density of fixed P3HT molecules by changing both or either the volume or concentration of the injected P3HT solution.