A source of white-light radiation that generates few-cycle pulses with controlled peak power values has been developed. These ultrafast pulses have been observed by spectral broadening of 32 fs pulses through nonlinear self-phase modulation in a neon-filled hollow-fiber then compressed with a pair of chirped mirrors for dispersion compensation. The observed pulses reached transform-limited duration of 5.77 fs and their peak power values varied from 57 GW up to 104 GW at repetition rate of 1 kHz. Moreover, the applied method is used for a direct tuning of the peak power of the output pulses through varying the chirping of the input pulses at different neon pressures. The observed results may give an opportunity to control the ultrafast interaction dynamics on the femtosecond time scale and facilitate the regeneration of attosecond pulses. © 2016 Elsevier Ltd.

Huge amounts of alum sludge are generated by water treatment plants every day. The common disposal system of alum sludge in Egypt is to discharge it into the nearest waterways. The impact of aluminum toxicity released from sludge on aquatic life has become a significant environmental issue. Re-use of alum sludge in wastewater treatment may provide a solution for issues related to sludge disposal. It may also help to increase the performance of existing WWTPs, because that alum sludge contains a large portion of insoluble aluminum hydroxides that can be utilized as a coagulant in the wastewater settling processes. Therefore, this paper attempted to study the effect of alum sludge addition on primary and secondary wastewater settling processes. Also, effect of alum sludge addition on the characteristics of the settled primary and secondary wastewater sludge was investigated. Alum sludge and wastewater samples were applied to a series of Jar test experiments. Re-use of alum sludge achieved highly removal efficiency values for the primary and secondary settling processes. The volume of primary settled sludge increased and moisture content slightly increased. However, alum sludge found to have a slight effect on the using of sludge as fertilizer. Finally, SVI values for secondary precipitated sludge decreased, which can solve the problems related to bulking in the secondary settling tanks.

Labile-barleys (Hordeumvulgare L. convar. labile (Schiem.) Mansf.) Are found in the highlands of Ethiopia, Eretria and North India-Pakistan districts. They represent a distinct spike form showing row-type alterations even within individual spikes of the same genotypes. Variation at the six-rowed spike 1 (vrs1) locus is sufficient to control barley lateral spikelet fertility, which is also modified by alleles at the intermedium-c (int-c) locus. This study aimed at re-sequencing these two loci to investigate whether labile-barleys have a two-rowed genetic background, resulting in increased lateral spikelet fertility, or show reduced lateral fertility if they possess a six-rowed genetic background. The Vrs1 re-sequencing results of 221 supposedly labile-barley accessions from Ethiopia revealed 13 accessions with two novel vrs1.a1 haplotypes. Following the current nomenclature of vrs1 haplotypes, the new haplotypes were named as haplotypes 66 and 67. Re-sequencing at the int-c locus showed that 118 of the labile-barleys possessed the previously described Int-c.a allele but only one accession was found having a novel Int-c.a haplotype in the homozygous state (termed Int-c.a haplotype1; Hap_1). Interestingly, 101 labile-barleys carried the Int-c.a allele and Int-c.a haplotype1 simultaneously, suggesting maintained heterozygosity or recent gene duplication at this locus. Only one accession had a two-rowed haplotype (Vrs1.b3, int-c.b1) and one accession possessed the Vrs1.t (deficiens) and Int-c.a alleles (six-rowed). These two accessions were considered as misclassified labile genotypes and not included in further analysis. Thus, these results confirmed that all of the 219 labile accessions studied in this work showed six-rowed alleles at vrs1 but reduced lateral spikelet fertility. This reduction is most likely caused by the recessive labile (lab) locus which we are in the process to characterize further.

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