Entangled Bessel beams

Orbital angular momentum (OAM) entanglement is investigated in the Bessel-Gauss (BG) basis. Having a readily adjustable radial scale, BG modes provide a more favourable basis for OAM entanglement over Laguerre-Gaussian (LG) modes. The OAM bandwidth in terms of BG modes can be increased by selection of particular radial modes and leads to a flattening of the spectrum. The flattening of the spectrum allows for higher entanglement. We demonstrate increased entanglement in terms of BG modes by performing a Bell-type experiment and violating the appropriate Clauser Horne Shimony Holt (CHSH) inequality. In addition, we reconstruct the quantum state of BG modes entangled in high-dimensions.Comment: 8 pages, 4 figure

The effect of hexose ratios on metabolite production in Saccharomyces cerevisiae strains obtained from the spontaneous fermentation of mezcal

Mezcal from Tamaulipas (Me´xico) is produced by spontaneous alcoholic fermentation using Agave spp. musts, which are rich in fructose. In this study eight Saccharomyces cerevisiae isolates obtained at the final stage of fermentation from a traditional mezcal winery were analysed in three semisynthetic media. Medium M1 had a sugar content of 100 g l-1 and a glucose/fructose (G/F) of 9:1. Medium M2 had a sugar content of 100 g l-1 and a G/F of 1:9. Medium M3 had a sugar content of 200 g l-1 and a G/F of 1:1. In the three types of media tested, the highest ethanol yield was obtained from the glucophilic strain LCBG-3Y5, while strain LCBG-3Y8 was highly resistant to ethanol and the most fructophilic of the mezcal strains. Strain LCBG-3Y5 produced more glycerol (4.4 g l-1) and acetic acid (1 g l-1) in M2 than in M1 (1.7 and 0.5 g l-1, respectively), and the ethanol yields were higher for all strains in M1 except for LCBG-3Y5, -3Y8 and the Fermichamp strain. In medium M3, only the Fermichamp strain was able to fully consume the 100 g of fructose l-1 but left a residual 32 g of glucose l-1. Regarding the hexose transporters, a high number of amino acid polymorphisms were found in the Hxt1p sequences. Strain LCBG-3Y8 exhibited eight unique amino acid changes, followed by the Fermichamp strain with three changes. In Hxt3p, we observed nine amino acid polymorphisms unique for the Fermichamp strain and five unique changes for the mezcal strains

Production of renewable fuel and value-added bioproducts using pineapple leaves in Costa Rica

Pineapple, Ananas comosus, is one of the most important cash crops in Costa Rica with more than 44,500 ha of plantation. The pineapple industry contributes approximately 1.7% of the gross domestic product (GDP) of Costa Rica. Pineapple cultivation generates a large amount of plant residues (250 metric tons per hectare of wet plant residues mainly leaves). Current practices of the field residue handing include direct burning, in situ decomposition and removal of residue before planting, which are neither economically sound nor environmentally friendly. New approaches are urgently needed to utilize the residues and improve sustainability of pineapple production in Costa Rica. This study developed a simple, efficient process to convert the pineapple plant leaves into bioethanol, spent yeast proteins, and fibrous material (pulp). The residue was first treated by a mechanical extruder to generate juice and fibrous material. The juice was fermented by a yeast, Kluyveromyces marxianus, to produce ethanol and spent yeast proteins. Under the selected process conditions, the plant leaves (125 tons fresh weight per year) from 1 ha can generate 2.1 tons of bio-ethanol, 1.55 tons of spent yeast biomass, and 11.65 tons of dry fibrous material. The mass and energy balance analysis concluded that using the studied process, the pineapple plant leaves from 44,500 ha of pineapple plantation in Costa Rica can produce 93,043, 68,975, and 518,425 tons of bioethanol, spent yeast, and fibrous material per year, respectively. The amount of bioethanol is able to replace approximately 8.51% of transportation fossil fuel consumption in Costa Rica.Michigan State University/[]/MSU/Estados UnidosNational Natural Science Foundation of China/[31701533]/NSFC/ChinaProgram of Study Abroad for Young Scholars/[gxgwfx 2018036]//Estados UnidosUCR::Vicerrectoría de Docencia::Ingeniería::Facultad de Ingeniería::Escuela de Ingeniería de Biosistema

Yeasts associated with the production of distilled alcoholic beverages

Distilled alcoholic beverages are produced firstly by fermenting sugars emanating from cereal starches (in the case of whiskies), sucrose-rich plants (in the case of rums), fructooligosaccharide-rich plants (in the case of tequila) or from fruits (in the case of brandies). Traditionally, such fermentations were conducted in a spontaneous fashion, relying on indigenous microbiota, including wild yeasts. In modern practices, selected strains of Saccharomyces cerevisiae are employed to produce high levels of ethanol together with numerous secondary metabolites (eg. higher alcohols, esters, carbonyls etc.) which greatly influence the final flavour and aroma characteristics of spirits following distillation of the fermented wash. Therefore, distillers, like winemakers, must carefully choose their yeast strain which will be very important in providing the alcohol content and the sensory profiles of spirit beverages. This Chapter discusses yeast and fermentation aspects associated with the production of selected distilled spirits and highlights similarities and differences with the production of wine

The uses of AFLP for detecting DNA polymorphism, genotype identification and genetic diversity between yeasts isolated from Mexican agave-distilled beverages and from grape musts

Aims: The objectives were to determine the variability and to compare the genetic diversity obtained using amplified fragment length polymorphism (AFLP) markers in analyses of wine, tequila, mezcal, sotol and raicilla yeasts. Methods and Results: A molecular characterization of yeasts isolated from Mexican agave musts, has been performed by AFLP marker analysis, using reference wine strains from Italian and South African regions. Conclusions: A direct co-relation between genetic profile, origin and fermentation process of strains was found especially in strains isolated from agave must. In addition, unique molecular markers were obtained for all the strains using six combination primers, confirming the discriminatory power of AFLP markers. Significance and Impact of the Study: This is the first report of molecular characterization between yeasts isolated from different Mexican traditional agave-distilled beverages, which shows high genetic differences with respect to wine strains

Increasing fermentation efficiency at high sugar concentrations by supplementing an additional source of nitrogen during the exponential phase of the tequila fermentation process

In the tequila industry, fermentation is traditionally achieved at sugar concentrations ranging from 50 to 100 gm L-1. In this work, the behaviour of the Saccharomyces cerevisiae yeast (isolated from the juices of the Agave tequilana Weber blue variety) during the agave juice fermentation is compared at different sugar concentrations to determine if it is feasible for the industry to run fermentation at higher sugar concentrations. Fermentation efficiency is shown to be higher (above 90%) at a high concentration of initial sugar (170 g L-1) when an additional source of nitrogen (a mixture of amino acids and ammonium sulphate, different than a grape must nitrogen composition) is added during the exponential growth phase

Effects of the addition of different nitrogen sources in the tequila fermentation process at high sugar concentration

Aims: To study the effect of the addition of different nitrogen sources at high sugar concentration in the tequila fermentation process. Methods and Results: Fermentations were performed at high sugar concentration (170 g l -1) using Agave tequilana Weber blue variety with and without added nitrogen from different sources (ammonium sulfate; glutamic acid; a mixture of ammonium sulfate and amino acids) during the exponential phase of growth. All the additions increased the fermentation rate and alcohol efficiency. The level of synthesis of volatile compounds depended on the source added. The concentration of amyl alcohols and isobutanol were decreased while propanol and acetaldehyde concentration increased. Conclusions: The most efficient nitrogen sources for fermentation rate were ammonium sulfate and the mixture of ammonium sulfate and amino acids. The level of volatile compounds produced depended upon types of nitrogen. The synthesis of some volatile compounds increased while others decreased with nitrogen addition. Significance and Impact of the Study: The addition of nitrogen could be a strategy for improving the fermentation rate and efficiency in the tequila fermentation process at high sugar Agave tequilana concentration. Furthermore, the sensory quality of the final product may change because the synthesis of the volatile compounds is modified. Zapotitlán 2007 The Authors