Pulmonary Tuberculosis Incidence and Risk Factors in Rural Areas of China: A Cohort Study

The incidence of tuberculosis (TB) and its risk factors in China remains unclear. This study examined TB incidence and relative risk factors in rural areas of China. Participants (n = 177,529) were recruited in Xiangtan County (in the central area of China) and in Danyang County (in the eastern area of China) in 2009 and a followed-up study was conducted for one year. The incidence density of pulmonary TB and smear-positive TB were 91.6 (95% CI: 78.7, 106.0) per 100,000 person-year and 36.7 (95% CI: 33.1, 52.4) per 100,000 person-year respectively in Xiangtan, and 47.3 (95% CI: 38.2, 57.5) per 100,000 person-year and 22.7 (95% CI: 16.5, 30.8) per 100,000 person-year in Danyang. The medical history of TB was associated with TB, with the relative risk (RR) of 7.00 (95% CI: 2.76, 17.18) in Xiangtan and that of 31.08 (95% CI: 13.22, 73.10) in Danyang. The association between TB and per capita living space over median was found in Xiangtan, with the RR of 1.86 (95% CI: 1.15, 3.01). No association was found between TB and the insurance status, the contact history with TB, the history of diabetes, smoking, or per capita annual income. The host genetic susceptibility, and social factors such as education and income could be considered in future studies.     

碳源对固定化细胞生产柠檬酸的影响

柠檬酸是利用微生物代谢生产的一种极为重要的有机酸．广泛应用于食品、饮料、化工、冶金、印染等各个领域。在国外,近10年来,利用固定化细胞生产柠檬酸已获得较广泛的研究^〔1－6〕,国内也有学者指出,柠檬酸发酵的趋向是利用固定化细胞进行连续化生产⑺。而国内这方面的研究报道很少〔8,9〕。我们利用海藻酸钙凝胶包埋固定化黑曲霉细胞生产柠檬酸．探讨了碳源种类及其浓度对固定化细胞生产柠檬酸的影响。现将结果报道如下。     

Nutrient Limitation on Ecosystem Productivity and Processes of Mature and Old-Growth Subtropical Forests in China

Nitrogen (N) is considered the dominant limiting nutrient in temperate regions, while phosphorus (P) limitation frequently occurs in tropical regions, but in subtropical regions nutrient limitation is poorly understood. In this study, we investigated N and P contents and N:P ratios of foliage, forest floors, fine roots and mineral soils, and their relationships with community biomass, litterfall C, N and P productions, forest floor turnover rate, and microbial processes in eight mature and old-growth subtropical forests (stand age >80 yr) at Dinghushan Biosphere Reserve, China. Average N:P ratios (mass based) in foliage, litter (L) layer and mixture of fermentation and humus (F/H) layer, and fine roots were 28.3, 42.3, 32.0 and 32.7, respectively. These values are higher than the critical N:P ratios for P limitation proposed (16–20 for foliage, ca. 25 for forest floors). The markedly high N:P ratios were mainly attributed to the high N concentrations of these plant materials. Community biomass, litterfall C, N and P productions, forest floor turnover rate and microbial properties were more strongly related to measures of P than N and frequently negatively related to the N:P ratios, suggesting a significant role of P availability in determining ecosystem production and productivity and nutrient cycling at all the study sites except for one prescribed disturbed site where N availability may also be important. We propose that N enrichment is probably a significant driver of the potential P limitation in the study area. Low P parent material may also contribute to the potential P limitation. In general, our results provided strong evidence supporting a significant role for P availability, rather than N availability, in determining ecosystem primary productivity and ecosystem processes in subtropical forests of China.     

Modeling with in vitro kinetic parameters for the elaboration of transfer RNA identity in vivo

A tRNA with "double identity" was created, and this tRNA was demonstrated in vitro to aminoacylate quantitatively with either of two amino acids. In contrast, acceptance of only one of these amino acids was observed in vivo, and a simple manipulation determined which one was accepted. Kinetic parameters were obtained for aminoacylation with each amino acid of the tRNA with double identity and of related tRNAs. Modeling with these parameters largely explains which amino acid specificity is observed in vivo. The results delineate some of the kinetic boundaries for the design and accommodation of tRNA sequence variations in the elaboration of identity in vivo.     

A Practicable Li/Na‐Ion Hybrid Full Battery Assembled by a High‐Voltage Cathode and Commercial Graphite Anode: Superior Energy Storage Performance and Working Mechanism

With the rapidly growing demand for low‐cost and safe energy storage, the advanced battery concepts have triggered strong interests beyond the state‐of‐the‐art Li‐ion batteries (LIBs). Herein, a novel hybrid Li/Na‐ion full battery (HLNIB) composed of the high‐energy and lithium‐free Na₃V₂(PO₄)₂O₂F (NVPOF) cathode and commercial graphite anode mesophase carbon micro beads is for the first time designed. The assembled HLNIBs exhibit two high working voltage at about 4.05 and 3.69 V with a specific capacity of 112.7 mA h g^?1. Its energy density can reach up to 328 W h kg^?1 calculated from the total mass of both cathode and anode materials. Moreover, the HLNIBs show outstanding high‐rate capability, long‐term cycle life, and excellent low‐temperature performance. In addition, the reaction kinetics and Li/Na‐insertion/extraction mechanism into/out NVPOF is preliminarily investigated by the galvanostatic intermittent titration technique and ex situ X‐ray diffraction. This work provides a new and profound direction to develop advanced hybrid batteries.     

The Effect of High-Temperature Stress on the Physiological Indexes,Chloroplast Ultrastructure,and Photosystems of two Herbaceous Peony Cultivars

In this study, two herbaceous peony cultivars with different heat tolerances (‘Fenyunu’ FYN low sensitivity and ‘Qiaoling’ QL high sensitivity) were used as research materials. An integrated view of the factors underlying the decrease in photosynthetic rate under high-temperature (HT) stress was provided by analyzing the biochemical parameters, chloroplast ultrastructure, gas-exchange parameters, chlorophyll fluorescence, and modulated 820 nm reflection of herbaceous peony leaves. The results showed that hydrogen peroxide, superoxide anion, malondialdehyde, and electrical conductivity increased significantly, while the photosynthetic pigments content and photosynthetic capacity decreased significantly in QL than in FYN under HT. The contents of soluble sugars and proline increased greatly in FYN than in QL, while the activity of SOD decreased markedly in QL than in FYN after HT. Compared with FYN, the ultrastructure of QL was more seriously disrupted under HT. Chlorophyll fluorescence analysis showed that HT changed the shapes of OJIP curve, resulting in the increase of K phase and J phase. The PSII acceptor side was more damaged than the donor side, and the electron transfer was seriously blocked. The energy flow in the process of light energy absorption, capture, and electron transfer were significantly changed after HT stress. Meanwhile, PSI was also significantly inhibited, and the coordination of both photosystems decreased. The variation of these parameters in FYN was less than that in QL. These results suggested that FYN featured a more heat-tolerance ability as evidenced by the good performances on the antioxidant system, osmoregulatory capacity, and the thermostability of membranes and photosystems.

     

Effects of ROS and caspase-3-like protein on the growth and aerenchyma formation of Potamogeton perfoliatus stem

Protoplasma - Aerenchyma formation plays an important role in the survival of Potamogeton perfoliatus in submerged environment. To understand the regulatory role of reactive oxygen species (ROS)...     

Changes of plant community composition instead of soil nutrient status drive the legacy effects of historical nitrogen deposition on plant community N:P stoichiometry

Plant and Soil - Uncovering the importance of soil and plant characteristics in driving the legacy effects of nitrogen (N) deposition on plant community nutrient stoichiometry would improve our...     

Efficient plant regeneration from in vitro leaves and petioles via shoot organogenesis in Sapium sebiferum Roxb.

Sapium sebiferum Roxb. is a widespread and economically important multipurpose tree due to its high value in ornamental, and biodiesel production as well as medicine. A highly efficient in vitro plant regeneration system through direct shoot organogenesis was established for the first time from leaves and petioles of S. sebiferum. The results showed that plant growth regulators (PGRs), mechanical damage, explant orientation, explant source, and developmental stage had a strong influence on the in vitro morphogenesis of S. sebiferum. For shoot organogenesis from leaves, the highest adventitious shoot induction rate (96.67%) with 25.67 shoots per explant was obtained when mechanically damaged leaves (the first three leaf explants at the top, leaf #1–3) were cultured with the abaxial surface placed down on Murashige and Skoog (MS) medium containing 0.5 mg L^?1 thidiazuron (TDZ). For in vitro morphogenesis of petioles, the combination of 1-naphthylacetic acid (NAA) and 6-benzylainopurine (6-BA) played a key role in cell fate determination. All of the in vitro petioles produced adventitious shoots on MS medium containing 1.0 mg L^?1 6-BA and 0.1 mg L^?1 NAA, while they produced green calli on medium fortified with 0.5 mg L^?1 6-BA and 1.0 mg L^?1 NAA. The shoots were subcultured in medium fortified with 0.5 mg L^?1 6-BA and 0.1 mg L^?1 NAA for multiplication and elongation. The elongated shoots successfully rooted on half-strength MS (1/2 MS) medium fortified with 0.5 mg L^?1 indole-butyric acid (IBA) and 0.25 mg L^?1 indole-3-acetic acid (IAA), and the regenerated plantlets successfully acclimatized with a survival rate of 92.56% in the greenhouse. The genetic fidelity of in vitro regenerated plants was evaluated using inter simple sequence repeat molecular markers. The in vitro regenerated plants were found to be the true to their mother plant. This study will be beneficial for the large-scale propagation as well as the genetic improvement of S. sebiferum.