A conserved domain in axonal targeting of Kv1 (Shaker) voltage-gated potassium channels

Axonal voltage-gated potassium (Kv1) channels regulate action-potential invasion and hence transmitter release. Although evolutionarily conserved, what mediates their axonal targeting is not known. We found that Kv1 axonal targeting required its T1 tetramerization domain. When fused to unpolarized CD4 or dendritic transferrin receptor, T1 promoted their axonal surface expression. Moreover, T1 mutations eliminating Kvbeta association compromised axonal targeting, but not surface expression, of CD4-T1 fusion proteins. Thus, proper association of Kvbeta with the Kv1 T1 domain is essential for axonal targeting.     

Effects of Feed Rate and Screw Speed on Operating Characteristics and Extrudate Properties During Single-Screw Extrusion Cooking of Rice Flour

Rice flour (37% moisture content) was used to examine the effects of feed rate and screw speed on the specific energy input during single-screw extrusion cooking. Torque, raised by decreasing screw speed or increasing feed rate, was found to be a power law function of the ratio of feed rate to screw speed (F_r/S_s) with r² > 0.94. Specific mechanical energy (SME) calculated from torque also was a power law function of F_r/S_s with r² >0.84 and negative power law indices. The SME obtained was in the 225–481 kJ/kg range. Thus the extruder can be considered low shear. Increasing SME raised the die temperature and decreased both intrinsic viscosity and water absorption index (WAI). The degree of gelatinization and intrinsic viscosity of extrudates also were power law functions of F_r/S_s. The intrinsic viscosity correlated well with the degree of gelatinization, WAI, and cooking loss, and appeared to be a good index of the extrudate properties. Different screw profiles also affect torque measurement.     

Multilocus phylogeography and ecological niche modeling suggest speciation with gene flow between the two Bamboo Partridges

Background: Understanding how species diversify is a long-standing question in biology. The allopatric speciation model is a classic hypothesis to explain the s...     

Comparison of postoperative effects between lidocaine infusion,meloxicam, and their combination in dogs undergoing ovariohysterectomy

ObjectiveTo compare the postoperative analgesic effects of intravenous (IV) lidocaine, meloxicam, and their combination in dogs undergoing ovariohysterectomy.Study designProspective, randomized, double‐blind, controlled clinical trial.AnimalsTwenty‐seven dogs aged (mean ± SD) 16.1 ± 7.5 months and weighing 22.4 ± 17.9 kg scheduled for ovariohysterectomy.MethodsAnaesthesia was induced with propofol and maintained with isoflurane. Dogs (n = 9 in each group) were allocated to receive just prior to and during surgery one of the following regimens: M group, 0.2 mg kg^?1 IV meloxicam then a continuous rate infusion (CRI) of lactated Ringer's at 10 mL kg^?1 hour^?1; L group, a bolus of lidocaine (1 mg kg^?1 IV) then a CRI of lidocaine at 0.025 mg kg^?1 minute^?1; and M + L group, both the above meloxicam and lidocaine treatments. Pain and sedation were scored, and venous samples taken for serum cortisol and glucose measurement before and at intervals for 12 hours after anaesthesia. Pain scores were assessed using a multi‐parameter subjective scoring scale (cumulative scale 0–21) by three observers. The protocol stated that dogs with a total score exceeding 9 or a sub‐score above 3 in any one category would receive rescue analgesia. Sedation was scored on a scale of 0–4.ResultsThere were no significant differences in subjective pain scores, serum cortisol, and glucose concentrations between the three groups. The highest pain score at any time was 5, and no dog required rescue analgesia. None of the three regimens caused any observable side effects during or after anaesthesia. At 1 and 2 hours after extubation dogs in group L were significantly more sedated than in the other two groups.Conclusions and Clinical relevanceThis study suggests that, with the scoring system used, IV lidocaine and meloxicam provide similar and adequate post‐operative analgesia in healthy dogs undergoing ovariohysterectomy.     

Mechanism of decay resistance of heartwood extracts from Acacia confusa against the brown-rot fungus Laetiporus sulphureus

Acacia confusa is an indigenous plantation species in Taiwan, and its heartwood has excellent decay resistance capability. The aim of this study is to investigate the resistance mechanisms of heartwood extracts from A. confusa against Laetiporus sulphureus (brown-rot). Results from wood block decay resistance tests indicate that aqueous crude extract and its three soluble fractions can significantly decrease the weight loss of wood blocks caused by L. sulphureus. However, none of the extracts can inhibit the growth of L. sulphureus on agar plate test. The performance of decay resistance from three soluble fractions is consistent with their antioxidant activities (DPPH free radical scavenging activity, reducing power and ferrous ion chelating ability). 3,4-Dihydroxybenzoic acid (3,4-DHBA), the compound present in three soluble fractions, exhibited excellent antioxidant activities and was proven to have excellent decay resistance ability against L. sulphureus. These findings suggest that 3,4-DHBA may be responsible for the inhibition of hydroxyl radical formation from Fenton reaction caused by L. sulphureus. Thus, 3,4-DHBA has good potential to be used as a novel and environmentally benign wood preservative.     

Porphyrin-sensitized solar cells with cobalt (II/III)-based redox electrolyte exceed 12 percent efficiency

The iodide/triiodide redox shuttle has limited the efficiencies accessible in dye-sensitized solar cells. Here, we report mesoscopic solar cells that incorporate a Co((II/III))tris(bipyridyl)-based redox electrolyte in conjunction with a custom synthesized donor-π-bridge-acceptor zinc porphyrin dye as sensitizer (designated YD2-o-C8). The specific molecular design of YD2-o-C8 greatly retards the rate of interfacial back electron transfer from the conduction band of the nanocrystalline titanium dioxide film to the oxidized cobalt mediator, which enables attainment of strikingly high photovoltages approaching 1 volt. Because the YD2-o-C8 porphyrin harvests sunlight across the visible spectrum, large photocurrents are generated. Cosensitization of YD2-o-C8 with another organic dye further enhances the performance of the device, leading to a measured power conversion efficiency of 12.3% under simulated air mass 1.5 global sunlight.