Si photonics has been receiving substantial attention as an integration platform in photonics and optoelectronic research, owing to the ability to manufacture low-cost, compact integrated circuits. However, realizing efficient and high-quality light sources remains a major challenge. Herein, we report an on-chip transferrable low-threshold single microdisk laser, which is fabricated by the microtransfer printing using a structured polymer. The optically transparent and adhesive microtip enables readily reproducible, damage-free, and precisely aligned targeted transfer of a single microdisk in the growth substrate onto a prefabricated Si-post on a silicon-on-insulator wafer. Spectroscopic measurements revealed that the microdisk laser with a small Si-post exhibits rich lasing actions with an estimated threshold of ∼96.8 μW. A controlled experiment revealed that laser devices with varied Si-post sizes exhibit no significant changes in optical properties until the size of the Si-post becomes comparable with that of the microdisk. These observations agreed with the results of systematic three-dimensional numerical simulations. We believe that our microtransfer printing technique can be used to transfer micro- and nanostructures onto targeted locations and realize complex microscale heterogeneous architectures in a compact integrated circuit.

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On-demand NW light sources in a photonic integrated circuit (PIC) have faced several practical challenges. Here, we report on an all-graphene-contact, electrically pumped, on-demand transferrable NW source that is fabricated by implementing an all-graphene-contact approach in combination with a highly accurate microtransfer printing technique. A vertically p−i−n-doped top-down-fabricated semiconductor NW with optical gain structures is electrically pumped through the patterned multilayered graphene contacts. Electroluminescence (EL) spectroscopy results reveal that the electrically driven NW device exhibits strong EL emission between the contacts and displays waveguiding properties. Further, a single NW device is precisely integrated into an existing photonic waveguide to perform light coupling and waveguiding experiments. Three-dimensional numerical simulation results show a good agreement with experimental observations. We believe that our all-graphene-contact approach is readily applicable to various micro/nanostructures and devices, which facilitates stable electrical operation and thus extends their practical applicability in compact integrated circuits.

PURPOSE: To summarize the evaluation tools of balance [Berg Balance Scale (BBS), timed up and Go (TUG), forward reaching test (FRT)], gait [6 m walking Test (6MWT)], and strength [Chair Stand Test (CST)] for patients with dementia. METHODS: The following databases were searched: Pub MED, Cochrane, Sciences Direct, and Web of Sciences. The inclusion criteria were as follows: 1) repeated measurement design, 2) subjects with dementia, 3) use of testing tools such as the BBS, TUG, FRT, 6MWT, and CST, 4) report the reliability. One reviewer performed the quality assessment of diagnostic accuracy study and two evaluators performed data extraction independently. RESULTS: Six articles and one letter were included. The interrater reliability of 6MWT, TUG, and CST, were acceptable (ICC>.90). However, FRT had unacceptable reliability. In test-retest reliability, only BBS has acceptable reliability (ICC>.90). Others had various reliabilities. The

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