Flexible Modulation of Electronic Band Structures of Wide Band Gap GaN Semiconductors Using Bioinspired,Nonbiological Helical Peptides

Modulation of the electronic band profiles of wide band gap GaN semiconductors is achieved by the macromolecular dipole potentials exerted from ordered monolayers of synthetic, nonbiological aldehyde terminated helical peptides deposited on wet chemically oxidized GaN surfaces functionalized with aminosilanes. The selective coupling of either N‐ or C‐terminal to the amino‐terminated surface enables one to control the direction of the dipole moment, while the number of amino acids determines its magnitude. After confirming the formation of highly ordered peptide monolayers, the impact of macromolecular dipole potentials is quantified by electrochemical impedance spectroscopy. Moreover, the chronoamperometry measurements of ferrocene‐terminated peptides suggest that the transfer of electrons injected from ferrocene follows inelastic hopping, while the current responses of peptides with no ferrocene moieties are purely capacitive. Finally, the same functionalization steps are transferred to GaN/AlGaN/GaN high electron mobility transistor structures. Stable and quantitative modulation of the current–voltage characteristics of the 2D electron gas by the deposition of bioinspired peptides is a promising strategy for the macromolecular dipole engineering of GaN semiconductors.     

Cellular and Exosomal Regulations of Sepsis-Induced Metabolic Alterations

Sepsis is a sustained systemic inflammatory condition involving multiple organ failures caused by dysregulated immune response to infections. Sepsis induces substantial changes in energy demands at the cellular level leading to metabolic reprogramming in immune cells and stromal cells. Although sepsis-associated organ dysfunction and mortality have been partly attributed to the initial acute hyperinflammation and immunosuppression precipitated by a dysfunction in innate and adaptive immune responses, the late mortality due to metabolic dysfunction and immune paralysis currently represent the major problem in clinics. It is becoming increasingly recognized that intertissue and/or intercellular metabolic crosstalk via endocrine factors modulates maintenance of homeostasis, and pathological events in sepsis and other inflammatory diseases. Exosomes have emerged as a novel means of intercellular communication in the regulation of cellular metabolism, owing to their capacity to transfer bioactive payloads such as proteins, lipids, and nucleic acids to their target cells. Recent evidence demonstrates transfer of intact metabolic intermediates from cancer-associated fibroblasts via exosomes to modify metabolic signaling in recipient cells and promote cancer progression. Here, we review the metabolic regulation of endothelial cells and immune cells in sepsis and highlight the role of exosomes as mediators of cellular metabolic signaling in sepsis.     

Functional Coating of Porous Silica Microparticles with Native Biomembranes towards Portable Flow‐Through Biochemical Microreactors

In biological cells, various transmembrane enzymes function as highly effective chemical reactors confined in space with characteristic length scales of tens of nanometers to micrometer. However, it is still challenging to quantitatively confine membranes in compact reactor platforms without losing their biochemical functions. Here, a simple and straightforward strategy towards the fabrication of a new flow‐through reactor by the functional coating of porous silica microparticles with sarcoplasmic reticulum membranes is described. After a short incubation, the membranes achieve the homogeneous, full coverage of the particle surface, spanning across pores with the diameter of about 100 nm. By using the underlying pores as cavity reservoirs, transmembrane enzyme (Ca²⁺‐ATPase) in the membrane retains their capability of ATP hydrolysis. This enables us to confine 1.1 m² of native membranes containing a large amount of Ca²⁺‐ATPase (approx. 10 nmol) in a column‐packaged, flow‐through reactor with merely 1.8 mL volume, which cannot be achieved by the reconstitution of proteins in artificial lipid membranes or condensation of membranes in suspensions. The distinct functional levels corresponding to different reaction buffers can be reproduced even after many buffer exchanges over 14 days, confirming the stability and reproducibility of the membrane‐particle hybrid reactors.     

Lattice physics analysis of measured isotopic compositions of irradiated BWR 9 × 9 UO2 fuel

As part of a validation study of burnup calculations of BWR cores, lattice physics analyses were performed on burnups and isotopic compositions of U, Pu and fission product nuclides measured on five samples taken from 9 × 9 BWR fuel assemblies. Burnup calculations in infinite assembly geometry were carried out using MVP-BURN and SRAC codes coupled with major nuclear data libraries. The burnups determined based on the Nd-148 method were from 27.9 to 64.2 GWd/t. The typical relative differences in isotopic compositions (atom/Total-U) between the burnup calculations and measurements were ?2 ～ 19% for ²³⁴U, ?20 ～ 3% for ²³⁵U, ?1.5 ～ 0.1% for ²³⁶U, ?0.04 ～ 0.02% for ²³⁸U, ?4 ～ 11% for ²³⁸Pu, ?11 ～ ?2% for ²³⁹Pu, ?3 ～ 0% for ²⁴⁰Pu, ?12 ～ ?2% for ²⁴¹Pu and ?2 ～ 3% for ²⁴²Pu. They were ?2 ～ 2% for Nd isotopes, ?15 ～ 7% for Eu isotopes, ?13 ～ 1% for Cs isotopes, ?13 ～ 8% for Sm isotopes, 0 ～ 7% for ¹⁴⁷Pm, ?7 ～ ?2% for ⁹⁵Mo, ?2 ～ ?1% for¹⁰¹Ru and 0 ～ 4% for ¹⁰³Rh.     

A Coupled-Reactor-Commutating Sinusoidal-Wave Inverter

A coupled-reactor-commutating sinusoidal-wave current-source inverter is described. The inverter consists of two coupled-reactor-commutating inverters. By superposing the output currents of these two inverters, output currents of a 180° conducting angle are formed, and are controlled in order to achieve a sinusoidal waveform. The operation and the control scheme of the inverter are described, and experimental results are presented. Compared with the usual PWM voltage-source inverters, the on-off frequency of each chopper may be decreased almost to one tenth of that of the PWM inverter.     

Development of Sustained-Release Tablets Containing Sodium Valproate: In Vitro and In Vivo Correlation

ABSTRACT

We have developed a 200 mg and 400 mg sustained-release sodium valproate tablet that allows effective blood concentration of the active drug with once-a-day dosing. The controlled dissolution or sustained release of the drug was attained by a membrane-controlled system. A single-coating system did not adequately control the dissolution rate, and therefore double-coated tablets were prepared and a human pharmacokinetic study was conducted. With the 200 mg VPA-Na tablets, the nonfasting C_max was only 20% higher than the fasting C_max. An in vitro dissolution test was conducted to predict the effects of food on drug dissolution after administration of this tablet. A relatively good correlation was observed between the absorption profiles and the dissolution profiles of the drug.     

Effects of ultrasonic irradiation on the viscosity of fuel oils

Fuel oil A, B and C, and a residual oil from vacuum distillation (R-Oil) have been irradiated with 25kHz ultrasonic waves (150W) at 50 °C for 10 h. The observed increases in the kinematic viscosity (Δ v%) are: fuel oil A, 0.3%; fuel oil B, 5.3%; fuel oil C, 17.6%; and R-Oil 5.5%. The value and sign of Δ v are found to change with the sample weight in the flask, l.r. measurements show that ultrasonic irradiation causes the intensities of CH₂ and CH₃ to decrease slightly. The ultrasonic energy appears to be used in the breaking-up and/or coupling of the petroleum molecules.     

Changes of physical and biochemical properties of Cryptosporidium oocysts with various storage conditions

Physical and biochemical properties of Cryptosporidium parvum oocyst were examined after storage under various conditions. Oocyst-positive-fecal samples recovered from calves were either stored in a 2.0% potassium dichromate solution (Cr) or deionized water (W), or kept as a fecal pellet (P), and stored at 4 or 18 degrees C for a maximum of 100 days. When stored in Cr at 4 degrees C, the morphology of oocysts and their ability to withstand ultrasonics was not affected by the storing media or the storage period. However, when stored at 18 degees C as a fecal pellet, the specific gravity of the oocysts increased and a significant decrease in the oocysts resistance to ultrasonics occurred. These changes in oocyst properties may affect the performance of methods used to detect oocysts in water samples. When using the current test methods or when developing a new test method, it is important to take these factors into consideration.