The cyanobacterium Synechocystis sp. PCC 6803 possesses multiple inorganic carbon (Ci) uptake systems that are regulated by Ci availability. The control mechanisms of these systems and their integration with other cell functions remain to be clarified. An analysis of the changes in global gene expression in response to Ci downshift and the inactivation of ndhR (sll1594), a LysR family regulator of Ci uptake is presented in this report. Mild Ci limitation (3% CO 2 (v/v) in air to air alone) induced a dramatic up-regulation of genes encoding both inducible CO 2 and HCO 3 ؊ uptake systems. An induction of ndhD5/ndhD6 and other genes in a probable transcriptional unit was observed, suggesting a function in inducible Ci uptake. The expression of slr1513 and sll1735, physically clustered with sbtA and ndhF3/ ndhD3/cupA, respectively, were also coordinated with upstream genes encoding the essential components for HCO 3 ؊ and CO 2 uptake. Ci limitation induced the regulatory genes slr1214, sll1292, slr1594, sigD, sigG, and sigH, among which slr1214, a two-component response regulator, showed the earliest induction, implying a role for the early response to Ci limitation. Opposite regulation of genes encoding the assimilation of carbon and nitrogen demonstrated a striking coordination of expression to balance C-and N-fluxes. The analyses revealed that ndhR inactivation up-regulated the expression of sbtA/sbtB, ndhF3/ndhD3/cupA/sll1735, and slr2006-13 including ndhD5 and ndhD6, indicating a vital role of this regulatory gene in both CO 2 and HCO 3 ؊ acquisition of the cyanobacterium. We therefore suggest that ndhR be renamed ccmR to better represent its broader regulatory characteristics.

This paper summarizes the current knowledge regarding the possible modes of action and nutritional factors involved in the use of essential oils (EOs) for swine and poultry. EOs have recently attracted increased interest as feed additives to be fed to swine and poultry, possibly replacing the use of antibiotic growth promoters which have been prohibited in the European Union since 2006. In general, EOs enhance the production of digestive secretions and nutrient absorption, reduce pathogenic stress in the gut, exert antioxidant properties and reinforce the animal’s immune status, which help to explain the enhanced performance observed in swine and poultry. However, the mechanisms involved in causing this growth promotion are far from being elucidated, since data on the complex gut ecosystem, gut function, in vivo oxidative status and immune system are still lacking. In addition, limited information is available regarding the interaction between EOs and feed ingredients or other feed additives (especially pro- or prebiotics and organic acids). This knowledge may help feed formulators to better utilize EOs when they formulate diets for poultry and swine.

The control of surface properties of all inorganic cesium lead halide perovskite (CsPbX3; X = Cl, Br, or I) quantum dots (QDs) is essential to achieve excellent stability and high photoluminescence quantum yields (PLQYs). Herein, a facile method was performed to simultaneously enhance the stability and PLQYs of CsPbX3 QDs by a ZnX2/hexane solution post-treatment. We show that the halogen defect on the surface of CsPbX3 QDs can be treated in a controlled way, whereby the “black dots” that adhered on the surface as observed by transmission electron microscopy have be completely removed, resulting in enhanced stability and photoluminescence. The PLQYs of CsPbCl3, CsPbBr3, and CsPbI3 increased from 4, 58, and 63% to 86, 93, and 95%, respectively, and the origin of the “black dots” as well as their transformation mechanism has been demonstrated. As a result, the poly­(dimethylsiloxane) composite films created by encapsulating stable and nearly defect-free green-emitting CsPbBr3, the red-emitting K2SiF6:Mn4+ phosphor, and a blue emission GaN chip were prepared and used to fabricate a remote-type white light-emitting diode device, which exhibits a high luminescence efficiency (≤98 lm/W) and a wide color gamut (∼130% of the National Television Standard Committee standard), suggesting the potential for liquid crystal display backlight application.

Good interfacial compatibility is the key to realize the full potential of metal−organic framework-based mix matrix membranes for gas separation. Here we report a new approach that uses polyimide brushes covalently grafted on the MOF surface to engineer the MOF-polymer interface. Benefiting from the strong brush−brush interaction, polyimide grafted MOF particles can form a stand-alone membrane at 88 wt % MOF loading without the addition of polymeric matrix. Compared to traditional mixed-matrix membranes, the modified membranes exhibit improved ductility up to 472%, reduced interfacial tearing phenomenon under shear force, decreased matrix chain mobility, and improved plasticization resistance against CO 2 . Most importantly, with increasing MOF loading, only the modified membranes exhibit simultaneous increase of selectivity and permeability for CO 2 /N 2 and CO 2 /CH 4 separation, following the trend predicted by the modified Maxwell model.