Doubly Periodic Instanton Zero Modes

Fermionic zero modes associated with doubly periodic SU(2) instantons of unit charge are considered. In cases where the action density exhibits two `instanton cores' the zero mode peaks on one of four line-segments joining the two constituents. Which of the four possibilities is realised depends on the fermionic boundary conditions; doubly periodic, doubly anti-periodic or mixed.Comment: 12 pages, 4 figure

Artificial intelligence-based software (AID-FOREST) for tree detection: A new framework for fast and accurate forest inventorying using LiDAR point clouds

Forest inventories are essential to accurately estimate different dendrometric and forest stand parameters. However, classical forest inventories are time consuming, slow to conduct, sometimes inaccurate and costly. To address this problem, an efficient alternative approach has been sought and designed that will make this type of field work cheaper, faster, more accurate, and easier to complete. The implementation of this concept has required the development of a specifically designed software called "Artificial Intelligence for Digital Forest (AID-FOREST)", which is able to process point clouds obtained via mobile terrestrial laser scanning (MTLS) and then, to provide an array of multiple useful and accurate dendrometric and forest stand parameters. Singular characteristics of this approach are: No data pre-processing is required either pre-treatment of forest stand; fully automatic process once launched; no limitations by the size of the point cloud file and fast computations.To validate AID-FOREST, results provided by this software were compared against the obtained from in-situ classical forest inventories. To guaranty the soundness and generality of the comparison, different tree spe-cies, plot sizes, and tree densities were measured and analysed. A total of 76 plots (10,887 trees) were selected to conduct both a classic forest inventory reference method and a MTLS (ZEB-HORIZON, Geoslam, ltd.) scanning to obtain point clouds for AID-FOREST processing, known as the MTLS-AIDFOREST method. Thus, we compared the data collected by both methods estimating the average number of trees and diameter at breast height (DBH) for each plot. Moreover, 71 additional individual trees were scanned with MTLS and processed by AID-FOREST and were then felled and divided into logs measuring 1 m in length. This allowed us to accurately measure the DBH, total height, and total volume of the stems.When we compared the results obtained with each methodology, the mean detectability was 97% and ranged from 81.3 to 100%, with a bias (underestimation by MTLS-AIDFOREST method) in the number of trees per plot of 2.8% and a relative root-mean-square error (RMSE) of 9.2%. Species, plot size, and tree density did not significantly affect detectability. However, this parameter was significantly affected by the ecosystem visual complexity index (EVCI). The average DBH per plot was underestimated (but was not significantly different from 0) by the MTLS-AIDFOREST, with the average bias for pooled data being 1.8% with a RMSE of 7.5%. Similarly, there was no statistically significant differences between the two distribution functions of the DBH at the 95.0% confidence level.Regarding the individual tree parameters, MTLS-AIDFOREST underestimated DBH by 0.16 % (RMSE = 5.2 %) and overestimated the stem volume (Vt) by 1.37 % (RMSE = 14.3 %, although the BIAS was not statistically significantly different from 0). However, the MTLS-AIDFOREST method overestimated the total height (Ht) of the trees by a mean 1.33 m (5.1 %; relative RMSE = 11.5 %), because of the different height concepts measured by both methodological approaches. Finally, AID-FOREST required 30 to 66 min per ha-1 to fully automatically process the point cloud data from the *.las file corresponding to a given hectare plot. Thus, applying our MTLS-AIDFOREST methodology to make full forest inventories, required a 57.3 % of the time required to perform classical plot forest inventories (excluding the data postprocessing time in the latter case). A free trial of AID -FOREST can be requested at [email protected]

PTRF acts as an adipokine contributing to adipocyte dysfunctionality and ectopic lipid deposition

Adipose tissue (AT) expands under obesogenic conditions. Yet, when the growth exceeds a certain limit, AT becomes dysfunctional and surplus lipids start depositing ectopically. Polymerase I and transcription release factor (PTRF) has been proposed as a mechanism leading to a dysfunctional AT by decreasing the adipogenic potential of human adipocyte precursors. However, whether or not PTRF can be secreted by the adipocytes into the bloodstream is not yet known. For this work, PTRF presence was investigated in plasma. We also produced a recombinant PTRF (rPTRF) and examined its impact on the functional interactions between the adipocyte and the hepatocyte in vitro. We demonstrated that PTRF can be found in human plasma, and is at least in part, carried by exosomes. In vitro treatment with rPTRF increased the hypertrophy and senescence of 3T3-L1 adipocytes. In turn, those rPTRF-treated adipocytes increased lipid accumulation in hepatocytes. Lastly, we found a positive correlation between circulating PTRF and the concentration of PTRF in the visceral fat depot. All these findings point toward the presence of an enlarged and dysfunctional visceral adipose tissue which secretes PTRF. This circulating PTRF behaves as an adipokine and may partially contribute to the well-known detrimental effects of visceral fat accumulation

Comparation of the new rebound tonometer IOPen and the Goldmann tonometer, and their relationship to corneal properties

Purpose To compare the intraocular pressures (IOPs) obtained with the IOPen rebound tonometer, Goldmann applanation tonometer (GAT) and the ocular response analyzer (ORA) and investigate the effects of corneal biomechanical properties on IOPen measurements. Methods A total of 198 normal eyes were included in this cross-sectional and randomized study. Three measurements were taken using IOPen. Agreement between tonometers was calculated using the Bland and Altman limits of agreement (LoA) analysis. Results The median IOPen IOP was 3mmHg below the GAT (Po0.001), 3mmHg below the ORA IOP similar to Goldmann (IOPg), and 3mmHg below the ORA IOP corrected using corneal parameters (IOPcc)(Po0.01). The LoA width between the IOPen and GAT IOPs varied between 13.92 (mean IOPen IOP) and 15.99mmHg (third IOPen measurement). The central corneal thickness (CCT) was unrelated to IOPen measurements (P40.05). Corneal hysteresis (CH) and corneal rigidity factor (CRF) were correlated with IOPen and GAT. Conclusions IOPen underestimated the IOP compared with GAT and ORA. The effect of measurement quality or measurement order on IOPen was low. CCT did not affect the IOPen, but the CH and CRF did. The LoA width between the IOPen and GAT IOPs was higher than between the ORA IOPg or ORA IOPcc and GAT IOPs

Hydrometallurgical extraction of Li and Co from LiCoO2 particles–Experimental and Modeling

The use of lithium-ion batteries as energy storage in portable electronics and electric vehicles is increasing rapidly, which involves the consequent increase of battery waste. Hence, the development of reusing and recycling techniques is important to minimize the environmental impact of these residues and favor the circular economy goal. This paper presents experimental and modeling results for the hydrometallurgical treatment for recycling LiCoO2 cathodes from lithium-ion batteries. Previous experimental results for hydrometallurgical extraction showed that acidic leaching of LiCoO2 particles produced a non-stoichiometric extraction of lithium and cobalt. Furthermore, the maximum lithium extraction obtained experimentally seemed to be limited, reaching values of approximately 65–70%. In this paper, a physicochemical model is presented aiming to increase the understanding of the leaching process and the aforementioned limitations. The model describes the heterogeneous solid–liquid extraction mechanism and kinetics of LiCoO2 particles under a weakly reducing environment. The model presented here sets the basis for a more general theoretical framework that would describe the process under different acidic and reducing conditions. The model is validated with two sets of experiments at different conditions of acid concentration (0.1 and 2.5 M HCl) and solid to liquid ratio (5 and 50 g L−1). The COMSOL Multiphysics program was used to adjust the parameters in the kinetic model with the experimental results.This work has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 778045. Paz-Garcia acknowledges financial support from the program “Proyectos I+D+i en el marco del Programa Operativo FEDER Andalucía 2014–2020”, No. UMA18-FEDERJA-279. Cerrillo-Gonzalez acknowledges the FPU grant obtained from the Spanish Ministry of Education. The University of Malaga is acknowledged for the financial support in the postdoctoral fellowship of Villen-Guzman

Exact evaluation of the nuclear form factor for new kinds of majoron emission in neutrinoless double beta decay

We have developed a formalism, based on the Fourier-Bessel expansion, that facilitates the evaluation of matrix elements involving nucleon recoil operators, such as appear in serveral exotic forms of neutrinoless double beta decay ($\beta\beta_{0\nu}$). The method is illustrated by applying it to the ``charged'' majoron model, which is one of the few that can hope to produce an observable effect. From our numerical computations within the QRPA performed for $^{76}Ge$, $^{82}Se$, $^{100} Mo$, $^{128}Te$ and $^{150}Nd$ nuclei, we test the validity of approximations made in earlier work to simplify the new matrix elements, showing that they are accurate to within 15%. Our new method is also suitable for computing other previously unevaluated $\beta\beta_{0\nu}$ nuclear matrix elements.Comment: 11pp., latex, fixed minor typographical error

Recovery of Li and Co from LiCoO2 via Hydrometallurgical–Electrodialytic Treatment

Lithium-ion batteries play an important role in our modern society as the main option to power portable electronic devices and electric vehicles. The growing demand for these batteries encourages the development of more efficient recycling processes, aiming to decrease the environmental impact of the spent batteries and recover their valuable components. In this paper, a combined hydrometallurgical-electrodialytic method is proposed for processing battery waste. In the combined technique, the amount of leaching solution is reduced as acid is generated via electrolysis. At the same time, the use of ion-exchange membranes and the possibility of electroplating allows for a selective separation of the target metals. Experiments were performed using LiCoO2, which is one of the most used cathodes in lithium-ion batteries. First, 0.1 M HCl solution was used in batch extractions to study the kinetics of LiCoO2 dissolution, reaching an extraction of 30% and 69% of cobalt and lithium, respectively. Secondly, hydrometallurgical extraction experiments were carried out in three-compartment electrodialytic cells, enhanced with cation-exchange membranes. Experiments yielded to a selective recovery in the catholyte of 62% of lithium and 33% of cobalt, 80% of the latter electrodeposited at the cathode.This work has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 778045. Financial support from E3TECH Excellence Network under project CTQ2017-90659-REDT (MCIUN, Spain) is acknowledged. Paz-Garcia acknowledges the financial support from the program “Proyectos I+D+i en el marco del Programa Operativo FEDER Andalucía 2014–2020”, No. UMA18-FEDERJA-279. Villen-Guzman acknowledges the postdoctoral fellowship obtained from the University of Malaga. Cerrillo-Gonzalez acknowledges the FPU grant obtained from the Spanish Ministry of Education

Chemical reduction of nitrate by zero-valent iron: Shrinking-Core versus Surface Kinetics Models

Zero valent iron (ZVI) is being used in permeable reactive barriers (PRB) for the removal of oxidant contaminants, from nitrate to chlorinated organics. A sound design of these barriers requires a good understanding of kinetics. Here we present a study of the kinetics of nitrate reduction under relatively low values of pH, from 2 to 4.5. We use a particle size of 0.42 mm, which is within the recommended size for PRBs (0.2 mm to 2.0 mm). In order to avoid possible mass-transfer limitations, a well-stirred reactor coupled with a fluidized bed reactor was used. The experiments were performed at constant pH values using a pH controller that allows to accurately track the amount of acid added. Since the reduction of H+ to H2 by the oxidation of ZVI will always be present for these pH values, blank experiments (without nitrate) were performed and the rate of this H+ reduction obtained. This rate of reduction was studied using three kinetic models: a regular empirical one, the Shrinking-Core Model (SCM), and the Surface Kinetics Model (SKM). The best performance was obtained from the SKM model. Therefore, this model was also used to study the results for the nitrate reduction, also with satisfactory results. In both cases, some assumptions are introduced to maintain a moderate number of fitting parameters.This research was funded by the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 778045, by the “Proyectos I + D + i en el marco del Programa Operativo FEDER Andalucía 2014–2020, No UMA18-FEDERJA-279” and the project from the University of Malaga, No. PPIT.UMA.B5.2018/17. Villen-Guzman acknowledges the postdoctoral fellowship obtained from the University of Malaga. Cerrillo-Gonzalez acknowledges the FPU grant obtained from the Spanish Ministry of Education