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Quorum sensing (QS) offers cell density dependent dynamic regulations in cell culture through devices such as synchronized lysis circuit (SLC) and metabolic toggle switch (MTS). However, there is still a lack of studies on cocultivation with a combination of different QS-based devices. Taking the production of isopropanol and salidroside as case studies, we have mathematically modeled a comprehensive set of QS-regulated cocultivation schemes and constructed experimental combinations of QS devices, respectively, to evaluate their feasibility and optimality for regulating growth competition and corporative production. Glucose split ratio is proposed for the analysis of competition between cell growth and targeted production. Results show that the combination of different QS devices across multiple members offers a new tool with the potential to effectively coordinate synthetic microbial consortia for achieving high product titer in cross-feeding cocultivation. It is also evident that the performance of such systems is significantly affected by dynamic characteristics of chosen QS devices, carbon source control and the operational settings. This study offers insights for future applications of combinational QS devices in synthetic microbial consortia.

The stigma (tip of the pistil) of medlar is wet and covered with stigmatic exudate at anthesis. The exudate contains many vesicles with abundant calcium precipitates. After deposition on th...

To analyze the prevalence and years lived with disability (YLD) from dental caries among children and adolescents and the time trends over the past two decades in Sichuan province, the largest province in west China.Based on the Global Burden of Disease Study 2015 (GBD2015), which systematically assessed the epidemiological characteristics of major diseases and their transitions by country and region from 1990 to 2015, we extracted the estimated results for China. We then used the Bayesian meta-regression method to estimate the sex- and age-specific prevalences and YLDs from dental caries among children and adolescents under 15 years old in Sichuan province and compared them with global and national indicators for the same period.In 2015, there were almost 6 million cases of dental caries in children and adolescents (aged15 years) in Sichuan province, accounting for 6% of the total cases in China. For children under 5 years, the prevalence of deciduous caries was 55.9%, and the YLDs value was 10.8 per 100,000, while it was 24.3% and 5.1 per 100,000 respectively among 5- to 14-year-olds; for those aged 5 to 14 years, the prevalence of permanent caries was 21.5%, and the YLDs value was 11.5 per 100,000. From 1990 to 2015, the prevalence of dental caries for children under 5 years increased substantially, by 16.2%, and the YLDs increased by 8.7%. Among those aged 5 to 14 years, the prevalence increased and the YLDs decreased.Dental caries remains a huge health burden in Western China. In contrast to the global and national data, the trend has increased rapidly over the past 25 years in this region. This work provides suggestions for the prevention and control for oral health in China with the policy of two-child.

We analyzed anther development in Amomum villosum Lour. (Zingiberaceae) using the periodic acid-Schiff's technique and Sudan black staining to test for the presence of starch and lipids, respectively. Our analyses showed that microspore mother cells of A. villosum lack typical callose walls, and numerous lipid granules appear in the cells early in development. Some starch granules are present in anther wall cells, but not in tapetal cells. After meiosis, numerous lipid granules remain unchanged in the microspores. During microspore development, some small starch granules first appear in the central cell region, and then the starch granules increase in size. After microspore division, the bicellular pollen grains become filled with starch and lipids, and remain in this state until the pollen grains reach maturity. At anthesis, the anther wall of A. villosum consists of several layers of endothecium cells with an evidently thickened radial wall, and some layers of parenchyma cells containing numerous starch granules.

The geographic population patterns of Lingula anatina across the Indo-West Pacific region are analyzed based on mitochondrial COI and nuclear EF-1α gene sequences. Compared with the remarkable morphological stasis, genetic evidence of extant Lingula species displays deep genetic divergence. Three distinct COI lineages were detected for L. anatina, one of which is from Qinhuangdao (Hebei, China, Bohai Sea), the other two from Beihai (Guangxi, China, Gulf of Tonkin). Individuals from South Japan have a very close relationship with one of the two COI lineages found in Beihai, which is also supported by EF-1α results, suggesting a relatively recent migration between South China Sea and East China Sea. Genetic distances between the three lineages of L. anatina are rather high (8.9%, 8.6%, and 2.7%), and those between L. anatina and L. adamsi is much higher (44.5%), compared to other marine invertebrates. Both tectonic evolution and the repeated Quaternary glaciations have contributed to the complex phylogeographic pattern found in these recent Lingula anatina populations.

The power-time curves of the micelle formation process were determined for the nonionic surfactant Tween80/nonaqueous solvent (DMF)/long-chain alcohol (n-heptanol, n-octanol, n-nonanol, and n-decanol) systems by titration microcalorimetry at temperatures of (298.15, 303.15, 308.15, and 313.15) K. From the power-time curves, the CMC and \(\Delta H_{\mathrm{m}}^{\uptheta}\) values were obtained. The corresponding values of \(\Delta G_{\mathrm{m}}^{\uptheta}\) and \(\Delta S_{\mathrm{m}}^{\uptheta}\) were also calculated. The relationships of the CMC with the carbon number of the alcohol, the concentration of alcohol, and the temperature, along with the thermodynamic functions, are discussed.

The power−time curves of the micelle formation process are determined for the nonionic surfactants (Brij-35 and TX-100) in dimethylformamide (DMF) + long-chain alcohol systems by titration microcalorimetry. From the power−time curves, the critical micelle concentration (cmc) and the ΔHθm are obtained with ΔGθm and ΔSθm calculated. For this system, the relationships among the alcohol carbon number, the alcohol concentration with cmc, and the thermodynamic functions are discussed.

Pseudopodoces humilis, a long misclassified terrestrial tit, is the only species of parid whose distribution is limited to treeless terrain and endemic to the Tibetan Plateau. We revealed the phylogeographic structure of the species by using mitochondrial control region, as well as comparing morphological characters. The distinct geographic distributions of two major clades suggest spatial and temporal separations that coincide with important climatic and paleogeographic changes following the uplift of the Tibetan Plateau. Population expansion was inferred for the population at the platform of the Plateau 0.17 million years before present (Ma B.P.), and restricted gene flow with isolation by distance was detected within this region, congruent with expansion occurring after the extensive glacial period. A significant decrease in body size with decreasing altitude was found, possibly indicating selection for larger-sized birds at higher altitude.