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Abstract  The maize genome remains abundant in molecular diversity, and the rich genetic diversity of maize starch-synthesis genes is crucial for controlling various grain traits. To explore the unique mechanism controlling the advantageous waxy trait and characterize the molecular feature of genes relevant to starch composition in two elite waxy inbreds, expression profiling combined with gene organization analysis was performed in them as compared to one normal inbred. Genotype-specific expression patterns were observed for most genes studied. The waxy inbreds were shown to contain mutations in multiple starch-synthesis genes, namely gbssI (wx), gbssIIb and isa2 (potentially isa3 too).The mis-splicing events directly accounted for wx loss of function. Contrarily, disruption of 5′ and 3′ transcript sequence may contribute to the absence of GbssIIb and Isa2 transcripts in waxy inbreds, respectively. Besides, the splicing of Sugary1 transcript was developmentally regulated in the normal inbred, and DNA polymorphisms were detected within SSIIIb-1 gene in waxy inbreds. [ABSTRACT FROM AUTHOR]

The article focuses on Shenmei #3, a strawberry cultivar hybridized by the Forestry & Fruit Research Institute (FFRI) of the Shanghai Academy of Agricultural Sciences (SAAS) in China. The plants and fruits of this cultivar are powdery mildew-resistant. The appearance of leaves and fruit of Shenmei #3 are described. The findings on the quality and ascorbic acid content of the fruit are detailed.

Superovulation is a key technique in embryo transfer. This study aimed to investigate the effects of two different sources of FSH (Ningbo Second Hormone Factory – NSHFTM, China and Vetoquinol, Australia), FSH injection methods (decreasing dose and equal dose), embryo collection methods (injection-type flushing tube and three-channel type flushing tube) and seasons (winter and spring) on superovulation response in Belgian Blue cattle. For this purpose, 80 Belgian Blue cattle (aged 2-3 years, parity=1) were randomly divided into four groups, with each group was further divided into two sub-groups. Superovulation experiments were carried out through Cue-Mate+FSH+PGF2α+GnRH, followed by artificial insemination. The effects of the above four factors on superovulation response were determined by comparing the mean numbers of corpora lutea, total embryos and viable embryos. The results showed non-significant difference in the effects of FSH produced by NSHFTM, China and Vetoquinol, Australia on the superovulation response, though the cost of NSHFTM was lower. Moreover, the superovulation response to decreasing-dose injection of FSH was significantly better than that of equal dose injection (P<0.05). Regarding embryo collection methods, the results of injection-type flushing tube were significantly better than those of three-channel type flushing tube (P<0.05). Similarly, superovulation results during spring season were significantly better than those during winter (P<0.05). In summary, the best method of superovulation in Belgian Blue cattle is to inject FSH with reduced dose/s and collect embryos through injection-type flushing tube method during spring season. [ABSTRACT FROM AUTHOR]

Culture of hippocampal neurons in low-Mg2+ medium (low-Mg2+ neurons) results in induction of continuous seizure activity. However, the underlying mechanism of the contribution of low Mg2+ to hyperexcitability of neurons has not been clarified. Our data, obtained using the patch-clamp technique, show that voltage-gated Na+ channel (VGSC) activity, which is associated with a persistent, noninactivating Na+ current (INa,P), was modulated by calmodulin (CaM) in a concentration-dependent manner in normal and low-Mg2+ neurons, but the channel activity was more sensitive to Ca2+/CaM regulation in low-Mg2+ than normal neurons. The increased sensitivity of VGSCs in low-Mg2+ neurons was partially retained when CaM12 and CaM34, CaM mutants with disabled binding sites in the N or C lobe, were used but was diminished when CaM1234, a CaM mutant in which all four Ca2+ sites are disabled, was used, indicating that functional Ca2+- binding sites from either lobe of CaM are required for modulation of VGSCs in low-Mg2+ neurons. Furthermore, the number of neurons exhibiting colocalization of CaM with the VGSC subtypes Nav1.1, Nav1.2, and Nav1.3 was significantly higher in low-Mg2+ than normal neurons, as shown by immunofluorescence. Our main finding is that low-Mg2+ treatment increases sensitivity of VGSCs to Ca2+/CaM-mediated regulation. Our data reveal that CaM, as a core regulating factor, connects the functional roles of the three main intracellular ions, Na+, Ca2+, and Mg2+, by modulating VGSCs and provides a possible explanation for the seizure discharge observed in low-Mg2+ neurons. [ABSTRACT FROM AUTHOR]

Objective: The present study evaluated the preservation of ram semen at 0°C using soybean lecithin with a Tris-fructose extender. Methods: Semen was collected by artificial vagina ejaculation from six rams with proven fertility. High quality ejaculates were diluted by soybean lecithin (0.25%, 0.5%, 0.75%, 1.0%, 1.25%) using Tris-fructose extender and control (Tris-fructose egg yolk extender), respectively. The ejaculates were diluted to a concentration of 5×108 sperm/mL, followed by cooling to 0°C in 90 min and maintaining the temperature for 12 days. The diluted semen samples were examined and recorded for sperm progressive motility, acrosome integrity at 0, 24, 72, 144, 216, 288 h, respectively. Two hundred and twenty-three ewes were inseminated for 216 h with optimal soybean lecithin concentrated semen or control via trans-cervical insemination. Results: The results showed that there were no differences in sperm progressive motility at 0, 24, 72, and 144 h (p>0.05). After 216 h, the sperm progressive motility in the control group and 0.5% concentration groups was significantly higher when compared to 0.25% concentration (p<0.05). The 0.5% concentration group demonstrated the highest survival rate and had no difference with the control group (p>0.05). At 216 h, the sperm progressive motility of all groups was still above 50%. The acrosome integrity of all groups was decreased with prolongation of storage time, but there was no difference at each time point (p>0.05). There was no significant difference in the lambing rate and pregnancy rate between the 0.5% concentration group and the control group (p>0.05). Conclusion: These results suggest that ram sperm is capable of fertilization after preservation at 0°C with 0.5% of soybean lecithin in Tris-based extender substituted for egg yolk and produce normal offspring after insemination. [ABSTRACT FROM AUTHOR]

We perform an experimental study of the multi-orbital effect on the high-order harmonic generation (HHG) from aligned N2 molecules in both linearly and elliptically polarized intense laser fields. Measured by a home-built extreme ultraviolet (XUV) flat grating spectrometer with the pump–probe method, the angular distributions of different orders of HHG are obtained, which show distinctive behaviors for harmonics in the plateau and the cut-off regions. The ellipticity dependence of HHG is investigated by aligning the molecular axis parallel or perpendicular to the laser polarization. Our results indicate that both the highest occupied molecular orbital (HOMO) as well as the lower one (HOMO-1) contribute to the HHG of N2 molecules, in either linearly or elliptically polarized intense laser field. The study paves the way for understanding the ultrafast electron dynamics of molecules exposed to an intense laser field. [ABSTRACT FROM AUTHOR]

We investigate experimentally multi-orbital effects in high-order harmonic generation (HHG) from aligned CO2 and N2O molecules by intense femtosecond laser fields with linear and elliptical polarizations. For either of the aligned molecules, a minimum in the harmonic spectrum is observed, the position of which shifts to lower-order harmonics when decreasing the intensity or increasing the ellipticity of the driving laser. This indicates that the minimum originates from the dynamic interference of different channels, of which the tunneling ionization and recombination are contributed via different molecular orbitals. The results show that both the highest occupied molecular orbital (HOMO) and low-lying HOMO-2 in CO2 (or HOMO-1 in N2O) contribute to the molecular HHG in both linearly and elliptically polarized strong laser fields. Our study would pave a way for understanding multi-electron dynamics from polyatomic molecules irradiated by strong laser fields. [ABSTRACT FROM AUTHOR]