Evaluation of autohydrolysis pretreatment using microwave heating for enzymatic saccharification of corn residues

Pretreatment of lignocellulosic materials (LCMs) is one of the most critical stages in the production of 2G bioethanol, this stage allows to maximize the production of fermentable sugars in the enzymatic saccharification process (ESP). Recently the microwave heating (MH) have been studied for enhanced the LCMs pretreatment, this technology reduces the energy requirements in the process, due to the fast heat transfer and it has allowed to redefine a lot of reactions which the thermal factor plays an essential role in the process. In this work were evaluated the effects of autohydrolysis pretreatment from corn residues using microwave heating and the pretreated solids as substrate in the enzymatic saccharification. The autohydrolysis pretreatment was performed using water as catalyst, the time (10, 30 and 50) and temperature (160, 180 and 200 ºC) were evaluated and the pretreated solids were used in the ESP. The enzymatic saccharification were performed with a working volume of 50 mL, 50 mM citrate buffer (pH 4.8), 2% (w/v) sodium with a cellulose concentration of 1 % (w/v) and incubated at 50 °C. The CellicCTec2 - cellulase was used with a loading of 20 FPU/g. This work showed that microwave autohydrolysis processing is an efficient pretreatment producing a solid enriched with cellulose (63.67±0.91) . The solid pretreated at 200 °C for 10 min was the best condition for saccharification yield (96.95% ± 0.79). This autohydrolysis pretreatment using microwave heating and enzymatic saccharification is a good alternative to obtain fermentable sugars for bioethanol production

Efecto del manejo de la cubierta vegetal en el control biológico de Tetranychus Urticae (Acari: Prostigmata) en Clementino

Tetranychus urticae ocasiona manchas en fruto que son especialmente temidas en mandarinas. Puesto que esta fruta se destina mayoritariamente al consumo en fresco, su valor comercial puede verse seriamente afectado. Como consecuencia de la naturaleza polífaga de este ácaro, nuestra hipótesis de trabajo fue que el manejo de la cubierta vegetal podía afectar a la dinámica poblacional tanto de T. urticae como de sus principales enemigos naturales, los ácaros depredadores de la familia de los Phytoseiidae. En estudios previos, en los que se caracterizó la acarofauna asociada a especies vegetales adventicias presentes en los huertos de cítricos, se observó que las gramíneas (Poaceae) presentaban una proporción Phytoseiidae : T. urticae más favorable que otras especies estudiadas. Consecuentemente, hemos comparado el efecto de una cubierta sembrada de Festuca arundinacea (Poaceae) frente a las alternativas tradicionales de suelo desnudo y cubierta vegetal espontánea. Desde 2006, se ha realizado el seguimiento de las poblaciones de ácaros en cuatro parcelas comerciales de clementino en las que se ha delimitado tres áreas de estudio de 1 ha en las que se ha llevado a cabo una diferente gestión de la cubierta vegetal: (a) Cubierta espontánea, (b) Cubierta sembrada de Festuca arundinacea y (c) Suelo desnudo. Como esperábamos, la cubierta sembrada de F. arundinacea fue la que presentó menores poblaciones de T. urticae en el árbol. Los mecanismos que explican estos resultados pueden estar relacionados tanto con la composición específica de la de Phytoseiidae asociados a cada cubierta, como con una posible especialización alimenticia por parte de T. urticae en la cubierta de F. arundinaceaThe mite pest Tetranychus urticae causes fruit spots that are especially feared in mandarins as these fruits are intended mainly for fresh consumption, and commercial value can be severely affected. Because of the polyphagous nature of this mite, the working hypothesis of this study was that the management of vegetation cover could affect both the population dynamics of T. urticae and of its main natural enemies, which are predatory mites of the Phytoseiidae family. In previous studies that characterized the mites associated with adventitious plant species present in citrus orchards, it was observed that the grasses (Poaceae) harboured a proportion of Phytoseiidae, with a greater amount of T. urticae than of other species. In this experiment, the effect was compared of planted cover of Festuca arundinacea versus the traditional alternatives of bare soil and spontaneous vegetation cover. Since 2006, the mite population (Phytoseiidae in general and T. urticae in particular) has been monitored in four commercial plots of clementines (cv. Clementina de Nules grafted onto citrange Carizo), each in different municipalities in the province of Valencia, Spain; in each of these there were 3 study areas with different vegetation management: (a) spontaneous cover, (b) sown F. arundinacea and (c) bare soil. The results are presented for 2006 and 2007, and show, as expected, that where cover of F. arundinacea was planted, there were lower tree populations of T. urticae. The mechanisms that underlie these results may be related to both the specific composition of the Phytoseiidae associated with each type of cover, and as a possible food specialization by T. urticae on the F. arundinacea cover

Multidisciplinary approach to treatment with immune checkpoint inhibitors in patients with HIV, tuberculosis, or underlying autoimmune diseases

Autoimmune diseases; Checkpoint inhibition therapy; Human immunodeficiency virusEnfermedades autoinmunes; Terapia de inhibición de puntos de control; Virus de inmunodeficiencia humanaMalalties autoimmunes; Teràpia d'inhibició del punt de control; Virus de la immunodeficiència humanaWe reviewed the available information on the use of immune checkpoint inhibitors (ICIs) in populations with special conditions, namely, patients with HIV, tuberculosis, or underlying autoimmune disease. Available data show that treatment with ICIs is safe in patients with HIV; it is advisable, however, that these patients receive adequate antiretroviral therapy and have an undetectable viral load before ICIs are initiated. Tuberculosis reactivation has been reported with the use of ICIs, possibly due to immune dysregulation. Tuberculosis has also been associated with the use of immunosuppressors to treat immune-related adverse events (irAEs). Active tuberculosis must be ruled out in patients with symptoms or signs, and selected patients may benefit from screening for latent tuberculosis infection, although more data are required. Limited data exist regarding the safety of ICIs in patients with cancer and autoimmune disease. Data from observational studies suggest that up to 29% of patients with a preexisting autoimmune disease treated with an ICI present with an autoimmune disease flare, and 30% present with a de novo irAE of any type. The frequency of flares appears to differ according to the type of ICI received, with higher rates associated with PD-1/PD-L1 inhibitors. The most common autoimmune diseases for which patients reported flares with ICI therapy are rheumatoid arthritis, other inflammatory arthritis, and psoriasis. Most studies have reported flares or de novo irAEs associated with ICIs that were mild to moderate, with low rates of discontinuation and no deaths due to flares. Therefore, the use of ICIs in these patients is possible, but careful monitoring is required.ML-O's work is supported by the National Cancer Institute (#CA237619)

Physical interpretation of NUT solution

We show that the well-known NUT solution can be correctly interpreted as describing the exterior field of two counter-rotating semi-infinite sources possessing negative masses and infinite angular momenta which are attached to the poles of a static finite rod of positive mass.Comment: 7 pages, 1 figure, submitted to Classical and Quantum Gravit

Microwave heating processing as alternative of pretreatment in second-generation biorefinery: An overview

The development of a feasible biorefinery is in need of alternative technologies to improve lignocellulosic biomass conversion by the suitable use of energy. Microwave heating processing (MHP) is emerging as promising unconventional pretreatment of lignocellulosic materials (LCMs). MHP applied as pretreatment induces LCMs breakdown through the molecular collision caused by the dielectric polarization. Polar particles movement generates a quick heating consequently the temperatures and times of process are lower. In this way, MHP has positioned as green technology in comparison with other types of heating. Microwave technology represents an excellent option to obtain susceptible substrates to enzymatic saccharification and subsequently in the production of bioethanol and high-added compounds. However, it is still necessary to study the dielectric properties of materials, and conduct economic studies to achieve development in pilot and industrial scale. This work aims to provide an overview of recent progress and alternative configurations for combining the application of microwave technology on the pretreatment of LCMs in terms of biorefinery.Financial support is gratefully acknowledged from the Energy Sustainability Fund 2014-05 (CONACYT-SENER), Mexican Centre for Innovation in Bioenergy (Cemie-Bio), Cluster of Bioalcohols (Ref. 249564). This study was supported by the Secretary of Public Education of Mexico PROMEP project/103.5/13/6595 – UACOAH-PTC-292 and PROMEP project/DSA/103.5/14/10442 – UACOAH-PTC-312. We gratefully acknowledge support for this research by the Mexican Science and Technology Council (CONACYT, Mexico) for the infrastructure project - INFR201601 (Ref. 269461) and CB-2015-01 (Ref. 254808). The author A. Aguilar-Reynosa thanks to Mexican Science and Technology Council (CONACY, Mexico) for master fellowship support

On interrelations between Sibgatullin's and Alekseev's approaches to the construction of exact solutions of the Einstein-Maxwell equations

The integral equations involved in Alekseev's "monodromy transform" technique are shown to be simple combinations of Sibgatullin's integral equations and normalizing conditions. An additional complex conjugation introduced by Alekseev in the integrands makes his scheme mathematically inconsistent; besides, in the electrovac case all Alekseev's principal value integrals contain an intrinsic error which has never been identified before. We also explain how operates a non-trivial double-step algorithm devised by Alekseev for rewriting, by purely algebraic manipulations and in a different (more complicated) parameter set, any particular specialization of the known analytically extended N-soliton electrovac solution obtained in 1995 with the aid of Sibgatullin's method.Comment: 7 pages, no figures, section II extende