Bottom-up synthesized graphene nanoribbons and graphene nanoribbon heterostructures have promising electronic properties for high-performance field-effect transistors and ultra-low power devices such as tunneling field-effect transistors. However, the short length and wide band gap of these graphene nanoribbons have prevented the fabrication of devices with the desired performance and switching behavior. Here, by fabricating short channel (L ch ~ 20 nm) devices with a thin, high-κ gate dielectric and a 9-atom wide (0.95 nm) armchair graphene nanoribbon as the channel material, we demonstrate field-effect transistors with high on-current (I on > 1 μA at V d = −1 V) and high I on /I off ~ 105 at room temperature. We find that the performance of these devices is limited by tunneling through the Schottky barrier at the contacts and we observe an increase in the transparency of the barrier by increasing the gate field near the contacts. Our results thus demonstrate successful fabrication of high-performance short-channel field-effect transistors with bottom-up synthesized armchair graphene nanoribbons.

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During the metastatic phase, cancer cells require the dissolution of cadherin-mediated cell-cell adhesion and a dramatic re-organization of the cytoskeleton through epithelial-mesenchymal transition (EMT), thereby acquiring migratory and invasive capabilities. In most tumors, EMT is accompanied by hypoxia. However, the intracellular signaling molecule that mediates hypoxia-induced EMT remained overlooked. By utilizing the microarray database system of the Cancer Genome Atlas, we identified ubiquitin-specific protease 47 (USP47), a deubiquitinating enzyme, as a potential mediator of hypoxia-induced EMT. Immunofluorescence staining of human colorectal tissue microarrays revealed that USP47 is overexpressed in colorectal adenocarcinoma tissues compared with normal adjacent tissues. The expression of USP47 was found to be elevated in three different human colorectal cancer cell lines. The enhancement of USP47 in colorectal cancer cells under hypoxic conditions induced the disassembly of E-cadherin and promoted EMT through deubiquitination of Snail. Silencing of USP47 accelerated the proteasomal degradation of Snail and inhibited EMT. Notably, hypoxia-induced USP47 upregulation was mediated by Sox9. These results demonstrate, for the first time, the role for USP47, as a novel target of Sox9, in the regulation of EMT and metastasis of colorectal cancer cells.

ObjectiveTo quantify autonomic dysfunction in fibromyalgia patients compared to healthy controls using heart rate variability (HRV).MethodsSixteen patients with fibromyalgia and 16 healthy controls were recruited in this case control study. HRV was measured using the time-domain method incorporating the following parameters: total heartbeats, the mean of intervals between consecutive heartbeats (R-R intervals), the standard deviation of normal to normal R-R intervals (SDNN), the square root of the mean squared differences of successive R-R intervals (RMSSD), ratio of SDNN to RMSSD (SDNN/RMSSD), and difference between the longest and shortest R-R interval under different three conditions including normal quiet breathing, rate controlled breathing, and Valsalva maneuver. The severity of autonomic symptoms in the group of patients with fibromyalgia was measured by Composite Autonomic Symptom Scale 31 (COMPASS 31). Then we analyzed the difference between the fibromyalgia and control groups and the correlation between the COMPASS 31 and aforementioned HRV parameters in the study groups.ResultsPatients with fibromyalgia had significantly higher SDNN/RMSSD values under both normal quiet breathing and rate controlled breathing compared to controls. Differences between the longest and shortest R-R interval under Valsalva maneuver were also significantly lower in patients with fibromyalgia than in controls. COMPASS 31 score was negatively correlated with SDNN/RMSSD values under rate controlled breathing.ConclusionSDNN/RMSSD is a valuable parameter for autonomic nervous system function and can be used to quantify subjective autonomic symptoms in patients with fibromyalgia.