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A new Full-Spectrum Correlated-k Distribution has been developed, which provides an efficient means for accurate radiative transfer calculations in absorbing/emitting molecular gases. The Full-Spectrum Correlated-k Distribution can be used together with any desired solution method to solve the radiative transfer equation for a small number of spectral absorption coefficients, followed by numerical quadrature. It is shown that the Weighted-Sum-of-Gray-Gases model is effectively only a crude implementation of the Full-Spectrum Correlated-k Distribution approach. Within the limits of the Full-Spectrum Correlated-k Distribution model (i.e., an absorption coefficient obeying the so-called “scaling approximation”), the method is exact. This is demonstrated by comparison with line-by-line calculations for a one-dimensional CO2-N2 gas mixture as well as a two-dimensional CO2-H2O-N2 gas mixture with varying temperature and mole fraction fields.

Rivers are the major carriers of dissolved black carbon (DBC) from land to ocean; the sources of DBC during its continuous transformation and cycling in the ocean, however, are not well characterized. Here, we present new carbon isotope data for DBC in four large and two small mountainous rivers, the Yangtze and Yellow river estuaries, the East China Sea and the North Pacific Ocean. We found that the carbon isotope signatures of DBC are relatively homogeneous, and the DBC 14C ages in rivers are predominantly young and increase during continuous transport and cycling in the ocean. The results of charcoal leaching experiments indicate that DBC is released from charcoal and degraded by bacteria. Our study suggests that riverine DBC is labile and respired during transport and mixing into the ocean and that residual DBC is cycled and aged on the same time scales as bulk DOC in the ocean.

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Nine structural genes (furA, katG, inhA, kasA, Rv0340, iniB, iniA, iniC, and efpA) and two regulatory regions (the oxyR-ahpC intergenic region and the promoter of mabA-inhA) in 87 isoniazid (INH)-monoresistant and 50 INH-susceptible Mycobacterium tuberculosis isolates collected from five provinces of China were analyzed by sequencing. Eighty-two (94.3%) INH-resistant isolates had mutations in the katG gene, with the katG Ser315Thr mutation predominant (55.2%). No mutation at codon 463 of katG was detected among the 50 INH-susceptible isolates with different IS6110 fingerprints. In addition, there were 35 (40.2%) INH-resistant isolates that had a mutation at codon 463 of katG. Of the INH-resistant strains, 20 (23.0%) isolates harbored double mutations at two separate loci of katG. Mutations in the inhA promoter region occurred in 13 (14.9%) isolates; 4.6% of the isolates had inhA structural gene mutations, and 11.5% harbored mutations in the oxyR-ahpC intergenic region. Drug resistance-associated mutations were detected in the iniBAC region and efpA.Tuberculosis (TB) represents one of the world's greatest sources of mortality and morbidity, with approximately 8 million new infections and 2.5 million to 3 million deaths per year. China has one of the highest burdens of TB in the world, with the second-largest total number of TB cases globally (9, 34, 41). Currently, throughout the world, isoniazid (INH) and rifampin (RIF) together represent the backbone of short-course chemotherapy treatment for Mycobacterium tuberculosis infections. The rise of multidrug-resistant tuberculosis (MDR-TB), defined as TB showing resistance to at least INH and RIF, is a serious threat to TB control. The World Health Organization estimates that 50 million people worldwide are infected with MDR-TB. The highest percentages of MDR-TB cases that are newly contracted have been found in China (11%) and eastern Europe (7 to 14%) (5,10,11).RIF resistance appears to be mediated by mutations of the ␤ subunit of RNA polymerase, which is encoded by the rpoB gene. Previous work indicates that more than 95% of RIFresistant strains are associated with mutations within an 81-bp region of the rpoB gene. Specific mutations, insertions, and deletions have been detected, and this 81-bp region has been termed the rifampin resistance determinant region (7,13,42). In contrast, INH resistance is apparently controlled by a more complex genetic system that involves several genes (15, 31). INH, a first-line antituberculosis drug, has a simple chemical structure consisting of a pyridine ring and a hydrazide group. INH is a prodrug that enters actively growing tubercle bacilli by passive diffusion (4). The bifunctional bacterial enzyme catalase-peroxidase (KatG) converts INH to a range of oxygenated and organic toxic radicals that attack multiple targets in the mycobacterial cell (32, 33). The best-characterized target of these radicals is the cell wall mycolic acid, but DNA, carbohydrates, lipids, and DNA metabolism may be targeted as well (6). Reports suggest th...

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In hybrid organic-inorganic perovskite solar cells (PSCs), interfacial engineering can efficiently improve the photovoltaic performance. In this work, the planar π-conjugated porphyrin, zinc(II) 5,10,15,20-tetrakis[5-(p-acetylthiopentyloxy)phenyl]porphyrin, was developed to modify the interface between poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) and perovskite. The modified devices increased their highest power conversion efficiency (PCE) to 14.05% relative to 11.35% for the reference devices without modification. Such enhancement in efficiency is mainly attributed to the improved open-circuit voltage (Voc) and fill factor (FF), which benefit from fast hole-extraction and low charge recombination after the employment of well-aligned interlayer.