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In this paper, a phosphoric acid fuel cell integrated with reformer and evaporator is demonstrated. Oxidative steam reforming of methanol (OSRM) process is employed in this system in cooperated with a high efficient evaporator, and the reacted gas is sent into a phosphorus-acid fuel cell (PAFC) for direct power generation after surplus methanol/water filtration. The results show that the maximum power density of this hybrid system achieves 277 mW/cm2 without CO2 removal, while it achieves 485 mW/cm2 when employing pure hydrogen as the fuel.

In this article, poly-Si gate-all-around (GAA) field effect transistors (FETs) using sidewall damascene method are successfully demonstrated. By manipulating the stress which is imposed by nitride layer, the crystallinity of poly-Si channels can be modified easily by changing the thickness of nitride layer. The better crystallinity of the devices with 60 nm top nitride is attributed to larger average grain size and fewer defects, leading to higher field-effect carrier mobility compared to 40 and 80 nm top nitride layer devices. Both n-type and p-type devices exhibit superior electrical characteristics including higher on-state current of 40 μA/μm (n-type) and 26 μA/μm (p-type), steep subthreshold swing of 82 mV/dec. (n-type) and 104 mV/dec. (p-type), an extremely low drain-induced barrier lowering (DIBL) of 4.6 mV/V (n-type) and 16.6 mV/V (p-type), and high Ion/Ioff current ratio larger than seven orders of magnitude. The thermal stability and gate stress reliability measurement of sidewall damascene GAA nanowire poly-Si devices were also investigated. With better crystallinity, electrical characteristics of GAA nanowire poly-Si devices degrade less under same elevated temperature condition. Devices characteristics remain unchanged after long gate stress time. This simple fabrication process makes it a potential candidate for future three-dimensional integrated-circuit (3D-IC) and low-cost Internet of Things (IoTs) applications.

This paper presents a digitally controlled oscillator (DCO) with a low-complexity circuit structure that combines multiple delay circuits to achieve a high timing resolution and wide output frequency range simultaneously while also significantly reducing the overall power consumption. A 0.18 µm complementary metal–oxide–semiconductor standard process was used for the design, and measurements showed that the chip had a minimum controllable timing resolution of 4.81 ps and power consumption of 142 µW with an output signal of 364 MHz. When compared with other designs using advanced processes, the proposed DCO demonstrated the best power-to-frequency ratio. Therefore, it can output a signal at the required frequency more efficiently in terms of power consumption. Additionally, because the proposed DCO uses digital logic gates only, a cell-based design flow can be implemented. Hence, the proposed DCO is not only easy to implement in different processes but also easy to integrate with other digital circuits.

A digitally controlled oscillator (DCO) with cell-based design for all-digital phase-locked loop (ADPLL) in System-on-Chip (SoC) applications is presented. The proposed DCO not only can achieve high timing resolution, but also have small area. Simulation results of DCO show that timing resolution can be improved to 4.4ps with 0.0018mm2 area in 0.18µm CMOS technology. In addition, the proposed design can be implemented with standard cells, making it easily portable to different processes and very suitable for SoC applications.

Poly-Si GAA FETs using sidewall damascened method are successfully demonstrated. By manipulating the stress imposed by nitride layer, crystallinity of poly-Si can be modified by changing the thickness of top nitride. Devices with larger grain size and fewer defects lead to superior electrical characteristics. Hot carrier and gate stress reliability of devices were then investigated. With better crystallinity, electrical characteristics degrade less under hot carrier stress due to less electric field enhancement. On the contrary, degradation of gate stress reliability is less sensitive to different crystallinity level. This is owing to the smaller activation energy of hot carrier effect making it more sensitive to crystallinity. With better crystallinity, poly-Si GAA nanowire FETs possess not only better electrical characteristics but also degrade less under stressing.

Mammalian target of rapamycin (mTOR) plays a range of crucial roles in cell survival, growth, proliferation, metabolism, and morphology. However, mTOR forms two distinct complexes, mTOR complex 1 and mTOR complex 2 (mTORC1 and mTORC2), via association with a series of different components; this allows the complexes to execute their wide range of functions. This study explores further the composition of the mTORC2 complex. Utilizing Rictor knock-out cells, immunoprecipitation and mass spectrometry, a novel Rictor associated protein, heterogeneous nuclear ribonucleoprotein M (hnRNP M), was identified. The association between hnRNP M and Rictor was verified using recombinant and endogenous protein and the binding site was found to be within aa 1~532 of hnRNP M. The presence of hnRNP M significantly affects phosphorylation of SGK1 S422, but not of Akt S473, PKCα S657 and PKCζ T560. Furthermore, hnRNP M also plays a critical role in muscle differentiation because knock-down of either hnRNP M or Rictor in C2C12 myoblasts reduced differentiation. This decrease is able to be rescued by overexpression SGK S422D in hnRNP M knockdown C2C12 myoblasts. Taken together, we have identified a novel Rictor/mTOR binding molecule, hnRNP M, that allows mTORC2 signaling to phosphorylate SGK1 thus regulating muscle differentiation.

In reactions between solders and Cu, additions of minor alloying elements, such as Fe, Co or Ni, to solders often reduce the Cu 3 Sn growth rate. Nevertheless, the mechanism for this effect remains unresolved. To provide more experimental observations that are essential for uncovering this mechanism, growth of Cu 3 Sn in the reaction between Cu and high-lead solders with or without Ni additions has been studied. The solders used for this study were 10Sn-90Pb and 5Sn-95Pb doped with 0 wt.%, 0.03 wt.%, 0.06 wt.%, 0.1 wt.% or 0.2 wt.% Ni. Reaction conditions included one reflow at 350°C for 2 min and solid-state aging at 160°C for up to 2000 h. The effect of Ni on the growth of Cu 3 Sn is discussed in detail based on the experimental results.

Stomata play an important role in plant innate immunity by limiting pathogen entry into leaves but molecular mechanisms regulating stomatal closure upon pathogen perception are not well understood. Here we show that the Arabidopsis thaliana L-type lectin receptor kinase-V.5 (LecRK-V.5) negatively regulates stomatal immunity. Loss of LecRK-V.5 function increased resistance to surface inoculation with virulent bacteria Pseudomonas syringae pv tomato DC3000. Levels of resistance were not affected after infiltration-inoculation, suggesting that LecRK-V.5 functions at an early defense stage. By contrast, lines overexpressing LecRK-V.5 were more susceptible to Pst DC3000. Enhanced resistance in lecrk-V.5 mutants was correlated with constitutive stomatal closure, while increased susceptibility phenotypes in overexpression lines were associated with early stomatal reopening. Lines overexpressing LecRK-V.5 also demonstrated a defective stomatal closure after pathogen-associated molecular pattern (PAMP) treatments. LecRK-V.5 is rapidly expressed in stomatal guard cells after bacterial inoculation or treatment with the bacterial PAMP flagellin. In addition, lecrk-V.5 mutants guard cells exhibited constitutive accumulation of reactive oxygen species (ROS) and inhibition of ROS production opened stomata of lecrk-V.5. LecRK-V.5 is also shown to interfere with abscisic acid-mediated stomatal closure signaling upstream of ROS production. These results provide genetic evidences that LecRK-V.5 negatively regulates stomatal immunity upstream of ROS biosynthesis. Our data reveal that plants have evolved mechanisms to reverse bacteria-mediated stomatal closure to prevent long-term effect on CO2 uptake and photosynthesis., Author Summary During their lifetime, plants face numerous pathogenic microbes. Plants recognize microbial pathogens via plant receptors and recognition leads to the activation of a general defense response. Some foliar pathogens such as bacteria enter plant leaves through natural surface openings such as stomata. To restrict bacterial entry, plants close stomata upon contact with bacteria. A better understanding of stomatal immunity may lead to development of crops with improved disease resistance. Here, we used the model plant Arabidopsis thaliana to study activation of defense responses after infection by Pseudomonas syringae pv. tomato (Pst) DC3000 bacteria. We found that a gene not previously known to function in the defense response, LecRK-V.5, is modulating Arabidopsis resistance. By studying plants with mutations in or overexpressing this gene, we show that LecRK-V.5 negatively regulates plant stomatal immunity to Pst DC3000. In addition, LecRK-V.5 is rapidly expressed at stomata upon activation of the general defense response. Plants with mutations in LecRK-V.5 also demonstrated constitutive accumulation of reactive oxygen species in stomatal guard cells. We conclude that LecRK-V.5 is a protein that negatively regulates closure of stomata upon bacterial infection.

We demonstrate the fabrication of polymer microring add-drop filters using multiphoton absorption polymerization and present the characterization of these devices.

We propose a novel coupling scheme between two waveguides, called “negative-gap”, and demonstrate this scheme in a benzocyclobutene micro-ring notch filter. Strong coupling and extinction of 28 dB at critical coupling were obtained.

We report progress in the development of polymer waveguides and devices for photonic applications in three areas: non-photolithographic techniques for polymer waveguide fabrication, bistability in laterally-coupled polymer microring resonators, and ultrafast photoconductive switches fabricated from semiconducting polymers. The non-photolithographic techniques for waveguide fabrication under development include laser milling with an excimer laser and programmable automatic dispensing of multimode polymer waveguides using an Essemtech automatic dispenser. Asymmetric diffraction gratings fabricated using phase masks and the interference of two excimer laser beams have exhibited concentration of optical power into the 1st diffraction order. Polymer micro-ring resonators laterally coupled to a bus line were fabricated by lithography from benzocyclobutene with radii as small as 10 μm and free spectral ranges on the order of 20 nm. These devices exhibit bistability in the frequency domain which can arise from thermal or nonlinear optical changes in refractive index and that may have application for all-optical switching. Metal-polymer-metal switches fabricated with interdigitated electrodes in an inverted structure exhibited fast transient photoconductive pulsewidths under 20 ps in response to femtosecond pump laser pulses, but the measurement was bandwidth limited by the oscilloscope. Here we report pump-probe measurements that indicate carrier lifetimes on the order of 2 ps.

We demonstrate polymer microring and microracetrack resonators made from benzocyclobutene. Our devices are among the smallest reported to-date.

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