D(--)-lactic acid and d(--)-lactate dehydrohgenase in octopus spermatozoa

The spermatozoa of Octopus dofleini martini produce anaerobically D(-)-lactic acid and possess a very active D(-)-lactate dehydrogenase. In this respect, while resembling certain microorganisms, they differ strikingly from mammalian spermatozoa which produce L(+)-lactic acid and contain L(+)-lactate dehydrogenase.     

Application of auditory signals to the operation of an agricultural vehicle: results of pilot testing

The operation of agricultural vehicles is a multitask activity that requires proper distribution of attentional resources. Human factors theories suggest that proper utilization of the operator's sensory capacities under such conditions can improve the operator's performance and reduce the operator's workload. Using a tractor driving simulator, this study investigated whether auditory cues can be used to improve performance of the operator of an agricultural vehicle. Steering of a vehicle was simulated in visual mode (where driving error was shown to the subject using a lightbar) and in auditory mode (where a pair of speakers were used to convey the driving error direction and/or magnitude). A secondary task was also introduced in order to simulate the monitoring of an attached machine. This task included monitoring of two identical displays, which were placed behind the simulator, and responding to them, when needed, using a joystick. This task was also implemented in auditory mode (in which a beep signaled the subject to push the proper button when a response was needed) and in visual mode (in which there was no beep and visual, monitoring of the displays was necessary). Two levels of difficulty of the monitoring task were used. Deviation of the simulated vehicle from a desired straight line was used as the measure of performance in the steering task, and reaction time to the displays was used as the measure of performance in the monitoring task. Results of the experiments showed that steering performance was significantly better when steering was a visual task (driving errors were 40% to 60% of the driving errors in auditory mode), although subjective evaluations showed that auditory steering could be easier, depending on the implementation. Performance in the monitoring task was significantly better for auditory implementation (reaction time was approximately 6 times shorter), and this result was strongly supported by subjective ratings. The majority of the subjects preferred the combination of visual mode for the steering task and auditory mode for the monitoring task.     

Cortical 5-HT2A receptor signaling modulates anxiety-like behaviors in mice

Serotonin [5-hydroxytryptamine (5-HT)] neurotransmission in the central nervous system modulates depression and anxiety-related behaviors in humans and rodents, but the responsible downstream receptors remain poorly understood. We demonstrate that global disruption of 5-HT2A receptor (5HT2AR) signaling in mice reduces inhibition in conflict anxiety paradigms without affecting fear-conditioned and depression-related behaviors. Selective restoration of 5HT2AR signaling to the cortex normalized conflict anxiety behaviors. These findings indicate a specific role for cortical 5HT2AR function in the modulation of conflict anxiety, consistent with models of cortical, "top-down" influences on risk assessment.     

Effects of time of progesterone supplementation on embryo development and interferon-tau production in the cow

We have investigated the effects of the timing of progesterone supplementation on early embryo development in mature, non-lactating Holstein-Friesian cows. Animals were inseminated 72 h (day 1) and 96 h following prostaglandin injection and were either left as untreated controls (n=6) or received progesterone supplementation from either days 5 to 9 (early; n=6) or from days 12 to 16 (late; n=6). Daily plasma samples were collected until day 16, when cows were slaughtered and reproductive tracts recovered and flushed to collect embryos and to measure interferon-tau activity. Both early and later progesterone supplementation resulted in marked increases in plasma progesterone (P<0.01). Early, but not late, progesterone supplementation resulted in a fourfold increase in trophoblast length (P<0.01) and a sixfold increase in uterine concentration of interferon-tau (P<0.05). The results demonstrate that progesterone supplementation during the postovulatory rise, but not later in the luteal phase, increases embryo development and interferon-tau production.     

Efficacy of Rinskor™ (florpyrauxifen-benzyl ester) on Herbicide Resistant Barnyardgrass (<Emphasis Type="Italic">Echinochloa crus-galli</Emphasis>) in Rice Fields of Mekong Delta,Vietnam

Barnyardgrass (Echinochloa crus-galli) seed samples were collected in rice fields in different locations at Mekong delta in Vietnam for herbicide resistance tests. The ALS-resistant and synthetic auxin-resistant E. crus-galli were confirmed at several locations in the Mekong Delta. The average LD₉₀ value of bispyribac, penoxsulam and quinclorac for assessed weed populations was 33.1, 15.1 and 550.2 g a.i.ha^?1 respectively. There were cross resistant barnyardgrass populations to bispyribac and penoxsulam, the LD₉₀ value of the two ALS inhibitors for E. crus-galli was positively correlated at R²=0.39, the cross resistant population was 33.3% of total sample. The correlation analysis was not useful to evaluate the multiple resistance between quinclorac and the two ALS inhibitors, the R² value was lower than 0.05, however, the percentage of multiple resistance weed was 36.2% of population. There was no cross resistance or multiple resistance among the 3 tested herbicides and the new synthetic auxin herbicide Rinskor?. All tested weed samples, including quinclorac-resistant populations, were effectively controlled by Rinskor?. There was no difference between control from Rinskor? in the different herbicide resistant populations. Average LD₉₀ value of Rinskor? in all tested barnyardgrass was 17.1 g a.i ha^?1.