Light-front wavefunction dependence of the quark recombination

We present an extension of the recombination formalism to analyze the effects from the variation of the hadron wavefunctions. The hadron spectra are sensitive to the shape of the wavefunctions. However, when we fit the wavefunction parameters to the physical observables, such as the average charge radius, the final spectra are very similar each other. We discuss our numerical results in comparison with the published PHENIX and STAR data at RHIC. In the hadron spectra, the recombination of thermal partons dominates at intermediate transverse momentum ($P_{T}$ = 2 $\sim$ 5 GeV), and the fragmentation dominates at high $P_{T}$ ($>$ 5 GeV). The yield ratios and the nuclear modification factors for various hadron species are also estimated and compared to the experimental data. We present a new prediction on $\bar{p}/p$ and $K^{-}/K^{+}$ ratios, including the jet quenching effects to the fragmentation mechanism.Comment: 26 pages, 7 figure

Role of A‐Site Composition in Charge Transport in Lead Iodide Perovskites

As the power conversion efficiency and stability of solar cells based on metal halide perovskites continue to improve, the community increasingly relies on compounds formed of mixed cations and mixed halides for the highest performing devices. The result is that device engineers now have a potentially infinite number of compositions to choose from. While this has provided a large scope for optimization, it has increased complexity of the field, and the rationale for choosing one composition over another remains somewhat empirical. Herein, the distribution of electronic properties for a range of lead iodide perovskite thin films is mapped. The relative percentages of methylammonium, formamidinium, and cesium are varied, and the electronic properties are measured with time-resolved microwave conductivity, a contactless technique enabling extraction of electronic properties of isolated films of semiconductors. It is found a small amount of Cs leads to larger carrier mobilities and longer carrier lifetimes and that compositions with a tolerance factor close to 0.9 generally show lower performance that those closer to 0.8 or 1.0

Electronic Stability of Metal Halide Perovskites

Despite near unanimous opinion on the consequences of climate change by scientific community, the rate at which carbon is emitted into the atmosphere continues to increase. The need for a clean and sustainable source of energy is therefore one of humankind's most urgent challenges. Solar energy is the most abundant energy source on Earth and the only one which is external to the planet. Metal Halide Perovskites (MHPs) are up-and-coming class of material that is spotlighted recently in solar cell community. The power conversion efficiency (PCE) of solar cells based on MHP has surpassed that of polycrystalline silicon based solar cells, despite being processable from low temperature. MHPs are an ionic material that is composed of two types of cations and one anion in the 1:1:3 ratio. This class of material is a good candidate for solar cell applications with excellent optoelectronic properties such as high absorption coefficient, high carrier mobility and long carrier lifetime. However, the most significant remaining barriers to commercialization are their poor stability under ambient conditions along with the toxicity of lead (Pb). A lot of research is ongoing to improve electronic stability of this class of material and it is mainly carried out with finalized devices. One of the main causes for instability is intrinsic property of the material itself, which can be ambiguous when studying the material in a completed device. In this context, a time-resolved microwave conductivity (TRMC) is used to analyze electronic properties of solution processed MHP thin films. TRMC enables one to study the electronic properties of materials without electrical contacts, hence enabling much more decisive statements to be made on the properties of the material. TRMC was applied to a range of MHPs in various environments including different over-annealing and humidity conditions. Moreover, by applying distinct functions to TRMC, changes in dielectric constant under illumination are studied as well as variability of mobilities within a sample. Finally, electronic properties were compared for a range of lead iodide perovskites depending on the cations

Isolation and characterization of the outer membrane of Escherichia coli with autodisplayed Z-domains

Abstract“Autodisplay technology” is an expression technique used to display the various recombinant proteins on the outer membrane (OM) of Escherichia coli. The resulting autodisplayed Z-domain has been used to improve the sensitivity of immunoassays. In this work, a facile isolation method of the OM fraction of E. coli with autodisplayed Z-domains was presented using (1) an enzyme reaction for the hydrolysis of the peptidoglycan layer and (2) short centrifugation steps. The purity of the isolated OM fraction was analyzed. For the estimation of contamination with bacterial proteins from other parts of E. coli, Western blots of marker proteins for the OM (OmpA), periplasm (β-lactamase), inner membrane (SecA), and cytoplasm (β-galactosidase) were performed. Additionally, assays of marker components or enzymes from each part of E. coli were carried out including the OM (KDO), inner membrane (NADH oxidase), periplasm (β-lactamase), and cytoplasm (β-galactosidase). The yield of OM isolation using this new method was determined to be 80% of the total OM amount, with less than 1% being contaminants from other parts of E. coli

N′-(4-Hydr­oxy-3-methoxy­benzyl­idene)-4-methoxy­benzohydrazide monohydrate

In the title compound, C16H16N2O4·H2O, the dihedral angle between the two aromatic rings is 19.6 (2)°. In the crystal structure, mol­ecules are linked into a three-dimensional network by inter­molecular N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds

Public Transportation Service Evaluations Utilizing Seoul Transportation Card Data

AbstractThis study evaluated transit service performance in Seoul using data collected from the Automatic Fare Collection (AFC) system in Seoul. The distance-based fare system in Seoul allows a maximum of four transfers with no additional charges to encourage transit ridership. In order to analyze the transit transfers, this study developed quantitative indicators for public transportation evaluations differentiated from those of previous studies by the fact that it utilizes data mining techniques which incorporate massive amounts of data (over 10 million transits per day) derived from the smart card system. This study not only carried out an evaluation to improve public transportation quality but provided comparative analysis of the mobility handicapped and an evaluation of public transportation users’ regional equity. This evaluative analysis of Level of Services (LOS) for various items is expected to be adopted for analyzing LOS status and generating improvement priorities and to be utilized as an objective database for public transportation policy decisions

N′-(5-Bromo-2-hydr­oxy-3-methoxy­benzyl­idene)-4-hydr­oxy-3-methoxy­benzohydrazide dihydrate

In the title compound, C16H15BrN2O5·2H2O, the dihedral angle between the two aromatic rings is 2.9 (2)° and an intra­molecular O—H⋯N hydrogen bond is observed. One of the water mol­ecule is disordered over two positions, with occupancies of 0.83 (3) and 0.17 (3). In the crystal structure, mol­ecules are linked into a three-dimensional network by inter­molecular O—H⋯O, O—H⋯(O,O), O—H⋯N and N—H⋯O hydrogen bonds. π–π inter­actions involving Br-substituted benzene rings, with a centroid–centroid distance of 3.552 (3) Å are also observed

Comparative analysis of FBS containing media and serum free chemically defined media, CellCor for adipose derived stem cells production

Background: As a result of the aging society, the average OECD life expectancy has grown to about 80 years, yet the average health life still remains at only 65 years, leaving more than 15 years of life in an uncertain health state. Regenerative medicine is a new concept of medicine that combines cells and biomaterials to restore the functions of aged or damaged tissues or organs. It is also a good treatment for chronic diseases and incurable diseases, receiving attention as a new paradigm for treating diseases. Problems: As the market for regenerative medicine grows, mass production of consistent quality cells is required. Media is the most important thing in mass production of consistent quality cells. However, the fetal bovine serum (FBS) containing media that is currently wide used has many problems, such as unidentified viral infection, immunogenicity, lot variations, unstable supply, and ethical issues. To solve these problems and make rapid progress in regenerative medicine, a high-performance serum free chemically defined media (CDM) is needed. Solution: CellCor is a serum free CDM that provides excellent performance, safety, economy and consistency in stem cell production. CellCor allows higher-speed cell production rate than current FBS containing culture media (Figure 1). Compared to the FBS containing media, CellCor is able to maintain stem cell markers, higher population homogeneity, genetic stability, and excellent differentiation potency even at later passage. Please click Additional Files below to see the full abstract