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Energy level alignment at organic semiconductor/metal interfaces: Effect of polar self-assembled monolayers at the interface We examined the electronic structure of the interfaces formed between pentacene and various metals: Au, Ag, and Ca, using photoemission spectroscopy. For all interfaces, we observed the formation of an interface dipole that varied linearly with the measured metal work function. We observed that the behavior of the interfaces of Ca with pentacene was symmetric with respect to whether Ca was deposited on pentacene or vice versa. On the other hand, the interfaces of Au and Ag with pentacene were asymmetric. For both Au and Ag we saw indications that upon metal deposition, metal penetration resulted in a metallic surface with a work function significantly different from that of pure Au or Ag. This also resulted in different interface dipoles for these interfaces.

Voltage fade of layered, Li-intercalating transition metal oxides is caused by irreversible, structural changes. A method that uses a resistance-corrected average voltage is proposed to track and quantify voltage fade in a reproducible and time-efficient manner. it is used here to compare several layered oxides in terms of their degrees of fade. The materials studied include some that are of current technological importance, such as LiNi 0.

The electronic structure and chemistry of interfaces between tris-(8-hydroxyquinoline) aluminum (Alq3) and representative group IA and IIA metals, Al, and Al/LiF have been studied by x-ray and ultraviolet photoelectron spectroscopies. Quantum-chemical calculations at the density functional theory level predict that the Alq3 radical anion is formed upon reaction with the alkali metals. In this case, up to three metal atoms can react with a given Alq3 molecule to form the trivalent anion. The anion formation results in a splitting of the N 1s core level and formation of a new feature in the previously forbidden energy gap. Virtually identical spectra are observed in the Al/LiF/Alq3 system, leading to the conclusion that the radical anion is also formed when all three of these constituents are present. This is support by a simple thermodynamic model based on bulk heats of formation. In the absence of LiF or similar material, the reaction of Al with Alq3 appears to be destructive, with the deposited Al reacting directly with the quinolate oxygen. We proposed that in those circumstances where the radical anion is formed, it and not the cathode metal are responsible for the electron injection properties. This is borne out by producing excellent injecting contacts when Ag and Au are used as the metallic component of the cathode structure.

Mitochondrial transport is critical for maintenance of normal neuronal function. Here, we identify a novel mitochondria protein, hypoxia up-regulated mitochondrial movement regulator (HUMMR), which is expressed in neurons and is markedly induced by hypoxia-inducible factor 1 α (HIF-1α). Interestingly, HUMMR interacts with Miro-1 and Miro-2, mitochondrial proteins that are critical for mediating mitochondrial transport. Interestingly, knockdown of HUMMR or HIF-1 function in neurons exposed to hypoxia markedly reduces mitochondrial content in axons. Because mitochondrial transport and distribution are inextricably linked, the impact of reduced HUMMR function on the direction of mitochondrial transport was also explored. Loss of HUMMR function in hypoxia diminished the percentage of motile mitochondria moving in the anterograde direction and enhanced the percentage moving in the retrograde direction. Thus, HUMMR, a novel mitochondrial protein induced by HIF-1 and hypoxia, biases mitochondria transport in the anterograde direction. These findings have broad implications for maintenance of neuronal viability and function during physiological and pathological states.

The electronic structures of pristine and Cs-doped CuPc films are investigated using photoemission spectroscopy and inverse photoemission spectroscopy (IPES). The lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital can be directly observed by IPES and ultraviolet photoemission spectroscopy simultaneously. We found that the Fermi-level position in organic film can be modified by Cs doping. The observed onset of the LUMO of the CuPc film is shifted by Cs doping to less than 0.2 eV above the Fermi level. The result indicates that the energy alignment and charge injection properties of the organic materials can be modified by a simple doping process.

Ovarian cancer is one of the common female malignant tumors globally. However, exactly mechanism of ovarian cancer remained unknown. HOTAIR, a lncRNA in the mammalian HOXC locus, has been fully explored for its genetic variants, expression level and carcinogenesis, development and progression of multiple cancers, except for ovarian cancer. In this study, we hypothesized that abnormal expression of HOTAIR and common variants of HOTAIR are associated with risk of Epithelial ovarian cancer (EOC). We first evaluated the HOTAIR levels in 100 paired tissues of EOC patients and corresponding normal tissues. Results showed that the expression level of HOTAIR in EOC tissues was significantly higher than that in corresponding normal tissues. Then the genotyping analyses of HOTAIR gene was conducted in a Chinese population. The results indicated that rs4759314 and rs7958904 were significantly associated with EOC susceptibility. For rs4759314, the difference between the G allele (as the reference) and the A allele was statistically significant (adjusted OR, 1.34; 95% CI: 1.08–1.65; P = 6.8 × 10−3). For rs7958904, C allele was associated a significantly decreased EOC risk when compared with G allele (OR: 0.77; 95% CI: 0.67–0.89; P = 4.2 × 10−4). The study identified that HOTAIR variants could be a useful biomarker for the predisposition to EOC and for the early diagnosis of the disease.

A series of thermoresponsive gating membranes, with a wide range of grafting yields, were prepared by grafting poly(N-isopropylacrylamide) (PNIPAM) onto porous poly(vinylidene fluoride) (PVDF) membrane substrates with a plasma-induced pore-filling polymerization method. The effect of grafting yield on the gating characteristics of thermoresponsive gating membranes was investigated systematically. The results showed that the grafting yield heavily affected both the water flux responsiveness coefficient and the thermoresponsivity of the membrane pore size. When the grafting yield was smaller than 2.81%, both the flux responsiveness coefficient and the thermoresponsivity of the membrane pore size increased with an increase in the grafting yield; however, when the grafting yield was higher than 6.38%, both the flux responsiveness coefficient and the thermoresponsivity of the membrane pore size were always equal to 1; i.e., no gating characteristics existed anymore. Diffusional permeation experiments showed that two distinct types of temperature responses were observed, depending on the grafting yield. The diffusional coefficient of a solute across membranes with low grafting yields increased with temperature, while that across membranes with high grafting yields decreased with temperature. To get a desired or satisfactory thermoresponsive gating performance, the membranes should be designed and prepared with a proper grafting yield.