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Dark fermentation holds great promise as a game-changing strategy in the field of biological hydrogen generation. With its ability to utilize a diverse range of organic feedstocks as a starting material, it offers the added advantage of waste valorization. Despite this, it has long been plagued by a low yield of hydrogen production when compared to traditional thermochemical processes. Recently, researchers have explored the use of nanoparticles as a means of intensifying the fermentation process. In this paper, the latest research on the use of metallic additives in dark fermentation, with a specific focus on naturally magnetic additives such as iron, nickel, and cobalt, is critically reviewed. The influence of these additives on the hydrogen generation process and the mechanisms that make it all happen are evaluated in detail. Optimal dosages for each additive type are also explored based on previous research. Finally, insightful suggestions for future research in this field are put forth. The conclusion is drawn that metal nanoparticles with natural magnetism, such as Fe, Ni, and Co, can improve hydrogen production, process stability, system start-up, and substrate utilization in dark fermentation. However, further research is needed to address various issues, including optimal dosage, operating conditions, microbial population dynamics, use of unconventional substrates, metal toxicity, morphology of metal additives, and potential risks generated by metals that remain in the system after fermentation. The exploration of combining several additives with complementary characteristics or properties is also proposed as an interesting line of research.

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The traditional logic behind effective microorganism is based on a media inoculation with mixed cultures of beneficial microorganisms to create a more favorable environment for plant growth and health when the media is the soil. Following this rationale, other research works have been focused on studying the effect of effective microorganisms when they are used as manure stabilizing agents, in some cases by including them in animal diets, reporting, in all cases, beneficial properties. However, the use of effective microorganisms is not yet widespread. One reason may be that no rigorous research has so far been done on the actual utility of these mixed cultures on manure stabilization and crop production. In this work, the potential uses of effective microorganisms are shown with the focus on evaluating the influence of these mixed cultures on the biostabilization of manure before its use as fertilizer. This work also presents some new perspectives on the role and application of effective microorganisms as microbial inoculants to achieve a microbiological balance of manure so that it can improve its quality, increasing production and protection of crops when applied as fertilizer, helping to conserving natural resources and creating a more sustainable agriculture and environment. Finally, this document also reviews strategies on how to improve the effect of effective microorganisms after their inoculation into the soil as part of the manure.

Within the transition to a bio-based economy from a fossil reserve-based world, we face the vital dare of closing nutrient cycles and moving to a more practical and balanced resource management, taking into account not only the economical but also the environmental perspective. The manufacture and transportation of mineral fertilizers are activities that require large amounts of fossil energy. Therefore, the dependence that agriculture has on fertilizers based on mineral reserves (mainly P, N, and K) should be considered as a very serious threat to human food security and climate change. On the other hand, the existing forecast on phosphorus reserves is pessimistic. According to the latest published figures on population growth and estimated demand for nutrients in the future, depletion of this material is expected to occur within a maximum of 300 years. At the same time, the agricultural demand that exists for mineral fertilizers is constantly growing. The main reason is the increase in the world population, together with the increase in meat consumption and the popularity of energy crops. Despite these negative perspectives, the processing or elimination of waste streams causes uncontrolled dispersion in the environment of a large amount of minerals. Thus, a new global effort is needed to draw a new scenario where improved nutrient use efficiency and, at the same time, reduced nutrient losses provide the bases for a more circular economy, to produce more necessary inputs, as food or energy, as the same time as decreasing environmental impact. This paper will show the process options which can “upcycle” and recover residual nutrients to high-quality end-products, defined by efficient nutrient use and will reveal the key issues to face with novel biofertilizer products and changing policies.

The machining of materials at micro and submicroscales is considered a key technology of the future and plays a role increasingly important in the miniaturization of complete machines, with important applications as bioengineering, MEMS, microsensors and microactuators. In this work the process of Pulsed Electrochemical Micromachining was studied. The experiments were carried out in a workpiece of Stainless Steel sunk in an electrochemical cell with an electrode of Tungsten with very small diameter (2-8μm). Pulses of voltage with very small width are introduced between the electrode and the part, so that the current is confined under the area of the tool tip. With this method microholes and microslots were obtained. It is observed that there is a minimum pulse-on time for each value of the voltage to make the current flow. Nevertheless, for values of voltage of 7V and higher there is always material removal for any value of pulse-on time. A maximum ratio between pulse-on time and period of 1/3 and an interelectrode gap in the order of micrometers are required to provide a localized material removal under the tip of the tool. In these conditions, the confinement will decrease when the pulse on-time increases. The main parameter that determines the material removal rate in the process is the current intensity. Surface roughness increases with pulse-on time, as well as the average current of the process and hence the material removal rate. Therefore, there is a compromise between surface finish and material removal rate.

Host infection by the pathogenic fungus Candida albicans is initiated by adhesion and mediated by binding to several host extracellular matrix proteins. Previously, we demonstrated that hemoglobin supplemented into a chemically defined medium significantly and specifically induced fibronectin binding to C. albicans. We now report that hemoglobin also induces binding of laminin, fibrinogen, and type IV collagen but not of thrombospondin-1 or type I collagen. The binding of each protein was inhibited by the respective unlabeled ligand in a concentration-dependent manner. Fibrinogen inhibited the binding of radiolabeled fibronectin, laminin, and fibrinogen with similar IC50 values, suggesting that a single promiscuous receptor recognizes these three proteins. Competitive binding studies indicated that a second class of receptor binds specifically to laminin. Growth of C. albicans in the presence of hemoglobin also increased cell adhesion to immobilized fibronectin, laminin, fibrinogen, and type IV collagen but not to thrombospondin-1 or type I collagen. Exposure to hemoglobin induced increased or de novo expression of several surface proteins on C. albicans. One of these proteins with a molecular weight of 55,000 recognized fibronectin, based on ligand protection and affinity chromatography on immobilized fibronectin. Thus, hemoglobin induces both promiscuous and specific receptors for extracellular matrix proteins and, therefore, may regulate matrix adhesion during dissemination of C. albicans infections.

La hiperplasia benigna de próstata se considera la causa más común de los síntomas del tracto urinario inferior. El sondaje vesical es el tratamiento urgente en pacientes con retención urinaria y la cirugía el de aquellos refractarios al tratamiento médico. Existe un grupo de personas con comorbilidades importantes no tributarias a cirugía. La embolización arterial prostática (EAP) podría presentarse como una alternativa segura y eficaz para conseguir el vaciamiento vesical y la micción espontánea, evitando así el sondaje vesical permanente en pacientes con comorbilidades importantes que contraindiquen la cirugía. En este estudio retrospectivo, evaluamos la eficacia de la EAP en pacientes portadores de sonda vesical permanente no tributarios de tratamiento quirúrgico.

In Chile, there is a lack of information regarding the lipid quality of bovine and vegetable milks and this can cause consumer confusion. The objective of this study was to characterize and compare the fatty acid (FA) composition between bovine (whole, semi-skimmed and skimmed) and vegetable milks that are offered in Chile. To maximize representativeness, the availability of bovine and vegetable milks in the three biggest stores located in five of the main cities of Chile was assessed in February 2015, before sampling. Santiago's stores presented the greatest offer of those beverages and therefore the analysis of the beverages found in Santiago's stores were evaluated. During a 4-wk period in March and April (summer) 2015, retail bovine milk (n= 62) and vegetable milk (n= 27) samples were collected. A multivariate analysis was performed to determine which FA were responsible for the differentiation between milk by origin and type of milk. The multivariable analysis included a correlation matrix, a factorial analysis (by principal components (PC) method) and a cluster analysis. Three PC were selected from factorial analysis, those explained 0.72 [PC 1 (0.54); PC 2 (0.11); and PC 3 (0.07)] of the overall variance in the data. PC 1 was related to the saturated FA and some monounsaturated FA such as C18:1 trans-11. High scores for this PC were associated with whole milk samples. PC 2 was represented by n-3 FA and the higher scores were found in semi-skimmed milk samples. PC 3 was related with C18:2 trans-9, trans-12 and C20:4 n-6 and skimmed milk samples; and vegetable milk showed the higher scores. C18:1 trans-11 and C18:2 cis-9, trans-11 were only found in retail bovine milk. Data were analyzed by using ANOVA and when significant differences were detected, means were separated using Tukey test. Compared with semi-skimmed, skimmed and vegetable milks, whole milk was higher (P< 0.05) in contents of saturated FA (10.3, 1.48 and 2.23 vs. 21.9 g/L) and monounsaturated FA (3.6, 0.48 and 5.4 vs. 7.3 g/L). Compared with bovine retail milk, vegetable milk had the highest (P< 0.05) contents of polyunsaturated FA (0.78 vs. 5.9 g/L) and this was related to its high content of C18:2 cis-9, cis-12. Data from this study can serve as a reference for estimating dietary intake for future studies. This study showed evidence that vegetable milk have a more “polyunsaturated FA profile” than retail bovine milk.

We construct the first analytic examples of topologically nontrivial solutions of the (3+1)-dimensional U(1) gauged Skyrme model within a finite box in (3+1)-dimensional flat space-time. There are two types of gauged solitons. The first type corresponds to gauged Skyrmions living within a finite volume. The second corresponds to gauged time crystals (smooth solutions of the U(1) gauged Skyrme model whose periodic time dependence is protected by a winding number). The notion of electromagnetic duality can be extended for these two types of configurations in the sense that the electric and one of the magnetic components can be interchanged. These analytic solutions show very explicitly the Callan-Witten mechanism (according to which magnetic monopoles may "swallow" part of the topological charge of the Skyrmion) since the electromagnetic field contributes directly to the conserved topological charge of the gauged Skyrmions. As it happens in superconductors, the magnetic field is suppressed in the core of the gauged Skyrmions. On the other hand, the electric field is strongly suppresed in the core of gauged time crystals. [ABSTRACT FROM AUTHOR]