Unlocking the potential of weberite-type metal fluorides in electrochemical energy storage

Sodium-ion batteries (NIBs) are a front-runner among the alternative battery technologies suggested for substituting the state-of-the-art lithium-ion batteries (LIBs). The specific energy of Na-ion batteries is significantly lower than that of LIBs, which is mainly due to the lower operating potentials and higher molecular weight of sodium insertion cathode materials. To compete with the high energy density of LIBs, high voltage cathode materials are required for NIBs. Here we report a theoretical investigation on weberite-type sodium metal fluorides (SMFs), a new class of high voltage and high energy density materials which are so far unexplored as cathode materials for NIBs. The weberite structure type is highly favorable for sodium-containing transition metal fluorides, with a large variety of transition metal combinations (M, M’) adopting the corresponding Na2MM’F7 structure. A series of known and hypothetical compounds with weberite-type structure were computationally investigated to evaluate their potential as cathode materials for NIBs. Weberite-type SMFs show two-dimensional pathways for Na+ diffusion with surprisingly low activation barriers. The high energy density combined with low diffusion barriers for Na+ makes this type of compounds promising candidates for cathode materials in NIBs

The Antibody Targeting the E314 Peptide of Human Kv1.3 Pore Region Serves as a Novel, Potent and Specific Channel Blocker

Selective blockade of Kv1.3 channels in effector memory T (TEM) cells was validated to ameliorate autoimmune or autoimmune-associated diseases. We generated the antibody directed against one peptide of human Kv1.3 (hKv1.3) extracellular loop as a novel and possible Kv1.3 blocker. One peptide of hKv1.3 extracellular loop E3 containing 14 amino acids (E314) was chosen as an antigenic determinant to generate the E314 antibody. The E314 antibody specifically recognized 63.8KD protein stably expressed in hKv1.3-HEK 293 cell lines, whereas it did not recognize or cross-react to human Kv1.1(hKv1.1), Kv1.2(hKv1.2), Kv1.4(hKv1.4), Kv1.5(hKv1.5), KCa3.1(hKCa3.1), HERG, hKCNQ1/hKCNE1, Nav1.5 and Cav1.2 proteins stably expressed in HEK 293 cell lines or in human atrial or ventricular myocytes by Western blotting analysis and immunostaining detection. By the technique of whole-cell patch clamp, the E314 antibody was shown to have a directly inhibitory effect on hKv1.3 currents expressed in HEK 293 or Jurkat T cells and the inhibition showed a concentration-dependence. However, it exerted no significant difference on hKv1.1, hKv1.2, hKv1.4, hKv1.5, hKCa3.1, HERG, hKCNQ1/hKCNE1, L-type Ca2+ or voltage-gated Na+ currents. The present study demonstrates that the antibody targeting the E314 peptide of hKv1.3 pore region could be a novel, potent and specific hKv1.3 blocker without affecting a variety of closely related Kv1 channels, KCa3.1 channels and functional cardiac ion channels underlying central nervous systerm (CNS) disorders or drug-acquired arrhythmias, which is required as a safe clinic-promising channel blocker

Corn Era Hybrid Response to Nitrogen Fertilization

Corn (Zea mays L.) N use is of continued interest due to agronomic performance and environmental issues. This 2-yr study evaluated era hybrid response to fertilizer nitrogen (FN) rate in a factorial arrangement of one popular hybrid per five decades (1960–2000 eras) and five N rates (0–224 kg N ha–1). An additional hybrid per era was grown at 168 kg N ha–1. Hybrid productivity and nitrogen use efficiency (NUE) increased across the eras, but not between the 1980 and 1990 eras. Grain yield (GY) increased 65% and total plant biomass 43%, however, total plant nitrogen uptake (PNU) increased only 19% and across N rates was only higher for the 2000 era. At the agronomic optimum nitrogen rate (AONR), there was a linear GY increase of 0.13 Mg ha–1 yr–1 and GY N response of 0.091 Mg ha–1 yr–1, indicating considerable genetic gain. There was no trend in AONR across eras. For plant N status measures, SPAD readings decreased and canopy index values increased across eras. All NUE measures indicated significant improvement in NUE. The apparent nitrogen recovery efficiency (NRE) at N rates near the AONR of each era, however, was not highest for the most recent eras. Harvest index (HI), grain nitrogen harvest index (GNHI), and fraction of total PNU accumulated by R1 were the same among eras. The grain nitrogen concentration (GNC), however, was 24% lower for the 2000 compared to the 1960 era. Corn hybrid development across the 50-yr period improved productivity and NUE, but not the AONR

Wnt/β-catenin/CBP signaling maintains long-term murine embryonic stem cell pluripotency

Embryonic stem cells (ESCs) represent an important research tool and a potential resource for regenerative medicine. Generally, ESCs are cocultured with a supportive feeder cell layer of murine embryonic fibroblasts, which maintain the ESCs' capacity for self-renewal and block spontaneous differentiation. These cumbersome conditions, as well as the risk of xenobiotic contamination of human ESCs grown on murine embryonic fibroblasts, make it a priority to develop chemically defined methods that can be safely used for the expansion of ESCs. Using a high-throughput, cell-based assay, we identified the small molecule IQ-1 that allows for the Wnt/β-catenin-driven long-term expansion of mouse ESCs and prevents spontaneous differentiation. We demonstrate that IQ-1, by targeting the PR72/130 subunit of the serine/threonine phosphatase PP2A, prevents β-catenin from switching coactivator usage from CBP to p300. The increase in β-catenin/CBP-mediated transcription at the expense of β-catenin/p300-mediated transcription is critical for the maintenance of murine stem cell pluripotency

Nitrogen utilization efficiency in maize as affected by hybrid and N rate in late-sown crops

After the introduction of Bt-maize, late sowing is becoming an important strategy to stabilize yields in many areas of the Argentine Pampas. Increased nitrogen (N) availability and sharp reduction in radiation and temperature during grain filling period are dominant features of late-sown maize. Deployment of late sowing therefore requires a better understanding of the nitrogen economy of the crop in a deteriorating photothermal environment. Our aims were to: (i) evaluate the effect of late sowing on the components of maize nitrogen utilization efficiency, i.e. grain yield per unit of N uptake, (ii) assess the interactions among sowing date, hybrid and N rate on N economy, (iii) study the links between biomass and N accumulation and partitioning involved in nitrogen utilization efficiency in late sown maize. Two irrigated experiments were conducted in Paraná, Argentina (−31°50; −60°31; 110 m.a.s.l) during two consecutive seasons. Treatments included the factorial combination of two hybrids with low (DK752MG) and high (DK682MG) harvest index (HI), two rates of N fertilization (0 and 200 kg N ha−1) and two contrasting sowing dates (September and December). Grain yield, shoot biomass, N concentration in grain, stover and biomass were measured. From these measurements we calculated N uptake, N accumulated in stover and grain and, N utilization efficiency for yield (NutEY) and biomass (NutEB) production as the ratio between yield or biomass and N uptake. A nitrogen nutrition index (NNI) was calculated to compare treatments at a similar N status. Late sowing increased soil N availability, hence reducing the response to N fertilization in comparison to traditional sowing, i.e. there were significant interactions between sowing date and N rate for most traits. The NNI accounting for the allometry of nitrogen and biomass proved to be an effective procedure in interpreting these interactions. The increase in N status reduced the NutEB, although at an equivalent NNI it was higher in traditional than in late sowing, which reflects the lower crop ability to use nitrogen in producing biomass when constrained by late growth. The hybrid DK682MG, showed more ability than DK752MG to allocate both biomass and N to grain in late sowing, as reflected by the higher HI and NHI as well as the lower amount of N accumulated in stover. Overall, our results support adaptive practices for late-sown maize in the Northern Pampas, including the use of hybrids with high partitioning of N and biomass to grain as well as the use of more conservative N fertilizer rates.Fil: Caviglia, Octavio Pedro. Universidad Nacional de Entre Ríos; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Entre Rios; ArgentinaFil: Melchiori, R. J. M.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Entre Rios; ArgentinaFil: Sadras, Victor Oscar. South Australian Research and Development Institute; Australi