FeCuNbSiB thin films with sub-Oersted coercivity

Nanocrystalline FeCuNbSiB thin films were fabricated through magnetron sputtering followed by heat treatment, resulting in samples characterized by low coercivity and high effective magnetization. Comprehensive microstructural analysis, employing X-ray diffraction and transmission electron microscopy techniques such as selected area electron diffraction, high-resolution imaging, and Fourier transform, was conducted. Magnetic properties were investigated using an alternating gradient field magnetometer and broadband ferromagnetic resonance. The structural analysis revealed a well-defined microstructure of nanograins within an amorphous matrix in all of our films. However, the coercivity of the 80 nm films did not exhibit as low values as observed for the 160 nm film

The LMT Galaxies' 3 mm Spectroscopic Survey: First Results

The molecular phase of the interstellar medium (ISM) in galaxies offers fundamental insight for understanding star-formation processes and how stellar feedback affects the nuclear activity of certain galaxies. We present here Large Millimeter Telescope spectra obtained with the Redshift Search Receiver, a spectrograph that cover simultaneously the 3 mm band from 74 to 111 GHz with a spectral resolution of around 100 km/s. The observed galaxies that have been detected previously in HCN, have different degrees of nuclear activity, one normal galaxy (NGC 6946), the starburst prototype (M 82) and two ultraluminous infrared galaxies (ULIRGs, IRAS 17208-0014 and Mrk 231). We plotted our data in the HCO+/HCN vs. HCN/13CO diagnostic diagram finding that NGC 6946 and M 82 are located close to other normal galaxies; and that both IRAS 17208-0014 and Mrk 231 are close to the position of the well known ULIRG Arp 220 reported by Snell et al. (2011). We found that in Mrk 231 -- a galaxy with a well known active galactic nucleus -- the HCO+/HCN ratio is similar to the ratio observed in other normal galaxies.Comment: Proceedings to appear in "Massive Young Star Clusters Near and Far: From the Milky Way to Reionization", 2013 Guillermo Haro Conference. Eds. Y. D. Mayya, D. Rosa-Gonzalez, & E. Terlevich, INAOE and AMC. 5 pages, 1 figur

Solutions to the Landau-Lifshitz-Gilbert equation in the frequency space: Discretization schemes for the dynamic-matrix approach

The dynamic matrix method addresses the Landau-Lifshitz-Gilbert (LLG) equation in the frequency domain by transforming it into an eigenproblem. Subsequent numerical solutions are derived from the eigenvalues and eigenvectors of the dynamic matrix. In this work we explore discretization methods needed to obtain a matrix representation of the dynamic operator, a fundamental counterpart of the dynamic matrix. Our approach opens a new set of linear algebra tools for the dynamic matrix method and expose the approximations and limitations intrinsic to it. Moreover, our discretization algorithms can be applied to various discretization schemes, extending beyond micromagnetism problems. We present some application examples, including a technique to obtain the dynamic matrix directly from the magnetic free energy function of an ensemble of macrospins, and an algorithmic method to calculate numerical micromagnetic kernels, including plane wave kernels. We also show how to exploit symmetries and reduce the numerical size of micromagnetic dynamic-matrix problems by a change of basis. This procedure significantly reduces the size of the dynamic matrix by several orders of magnitude while maintaining high numerical precision. Additionally, we calculate analytical approximations for the dispersion relations in magnonic crystals. This work contributes to the understanding of the current magnetization dynamics methods, and could help the development and formulations of novel analytical and numerical methods for solving the LLG equation within the frequency domain

Thiamethoxam in Papaya (Carica papaya Linnaeus) Agroecosystems

Papaya (Carica papaya L.) is a profitable fruit of economic and food importance in Mexico and Central America. Veracruz is the state in Mexico with the highest cultivable area, eventhough its production presents numerous phytosanitary problems, which are being faced with the use of the pesticide thiamethoxam. The aim of this study was to make a diagnosis of the use and management of thiamethoxam in papaya agroecosystems in the municipality of Cotaxtla, Veracruz. Two surveys were applied, one to a 30% of the total number of producers organized by an association dedicated to papaya culture, and the other survey was through key informants, both surveys were designed using the snowball sampling, a non-probability sampling technique. The results indicate that 6% of papaya producers use mainly the pesticide thiamethoxam, which belongs to the chemical group of neonicotinoids. It was found out that for five years there have been records of thiamethoxam use in vertisoils. During the cycle of papaya cultivation the producers use a maximum dose of 3 L/ha and a minimum dose of 250 ml/ha per crop cycle. One hundred per cent of those who apply thiamethoxam are not aware of its use and efficient management, nor of the damage they are doing or have caused to agroecosystems

Project Themyscira

Currently, both governments and private corporations are developing lunar exploration projects for scientific research and spaceflight operations. However, a viable plan for a lunar base is yet to be developed. The goal of Project Themyscira is to design a self-sufficient, sustainable lunar base capable of supporting five crew members for a period of six months. The feasibility study is two-fold. It will test the effectiveness and efficiency of the life-support systems to accomplish the mission, as well as evaluate its financial and logistic feasibility. In order to study the required systems to support human life, the team conducted an extensive literature survey on previous designs for human settlements in space and their limitations. This assessment yielded a series of constraints for oxygen production, atmospheric modeling, energy production, water treatment, and thermal regulation. Preliminary findings show that while some of the necessary support systems have the technology required to provide the necessary outputs, the logistics to set up the lunar base are not financially feasible. Nonetheless, artificial atmosphere models, artificial photosynthesis and radiation-protected photovoltaic cells are some of the existing technologies that would allow the lunar base to sustain human life. Consequently, optimizing the technologies so that they can be taken to space in smaller dimensions could result in logistical feasibility. The team will focus on developing testing methods to optimize the systems necessary to sustain the lunar base

Dynamics, aboveground biomass and composition on permanent plots, Tambopata National Reserve. Madre de Dios, Peru

In this study we evaluated the floristic composition and changes in stored biomass and dynamics over time in 9 permanent plots monitored by RAINFOR (Amazon Forest Inventory Network) and located in the lowland Amazon rainforest of the Tambopata National Reserve. Data were acquired in the field using the standardized methodology of RAINFOR. The biomass was estimated using the equation for tropical moist forests of Chave et al. (2005). Biomass dynamics were analyzed, in three separated periods from 2003 to 2011. 64 families, 219 genera and 531 species were recorded. The tree floristic composition is very similar in all plots except for one swamp plot, although but it is also evident that two slightly different forest communities exist in the rest of landscape, apparently related to the age of the ancient river terraces in the area. Mortality and recruitment of individuals averaged 2.12 ± 0.52% and 1.92 ± 0.49%, respectively. The turnover rate is 2.02% per year. Aboveground biomass stored in these forests averages 296.2 ± 33.9 t ha-1. The biomass dynamics show a total net gain of 1.96, 1.69 and -1.23 t ha-1 for period respectively. Prior to the drought of 2010 a change in biomass was found 1.88 t ha-1 yr-1 and post drought was -0.18 t ha-1 yr-1 on average, though the difference is not significant. Demographic analysis suggests a dynamic equilibrium in the plots. The negative balance of biomass observed for the period 2008 - 2011 may be due to the drought of 2010, in which half of the monitored plots experienced negative net biomass change due to mortality of individuals selectively affecting the floristic composition

Prophylactic Subacute Administration of Zinc Increases CCL2, CCR2, FGF2, and IGF-1 Expression and Prevents the Long-Term Memory Loss in a Rat Model of Cerebral Hypoxia-Ischemia

Prophylactic subacute administration of zinc decreases lipoperoxidation and cell death following a transient cerebral hypoxia-ischemia, thus suggesting neuroprotective and preconditioning effects. Chemokines and growth factors are also involved in the neuroprotective effect in hypoxia-ischemia. We explored whether zinc prevents the cerebral cortex-hippocampus injury through regulation of CCL2, CCR2, FGF2, and IGF-1 expression following a 10 min of common carotid artery occlusion (CCAO). Male rats were grouped as follows: (1) Zn96h, rats injected with ZnCl2 (one dose every 24 h during four days); (2) Zn96h + CCAO, rats treated with ZnCl2 before CCAO; (3) CCAO, rats with CCAO only; (4) Sham group, rats with mock CCAO; and (5) untreated rats. The cerebral cortex-hippocampus was dissected at different times before and after CCAO. CCL2/CCR2, FGF2, and IGF-1 expression was assessed by RT-PCR and ELISA. Learning in Morris Water Maze was achieved by daily training during 5 days. Long-term memory was evaluated on day 7 after learning. Subacute administration of zinc increased expression of CCL2, CCR2, FGF2, and IGF-1 in the early and late phases of postreperfusion and prevented the CCAO-induced memory loss in the rat. These results might be explained by the induction of neural plasticity because of the expression of CCL2 and growth factors

Application of Air Micronanobubbles to Reduce Arsenic Present in an Effluent Generated at the Laboratory Level

The objective of this research was applying air Micronanobubbles to reduce Arsenic present in an effluent generated at the laboratory level. In this research, an effluent with arsenic metal was used from a mixture of minerals with the presence of arsenopyrite with 19% As content. This mixture of minerals was stirred in a hot alkaline leaching medium at a temperature of 80 °C, with Na2S (1.5 M) and NaOH (1.0 M), then it was diluted with distilled water to obtain a volume of 100 L with a concentration of 150 ppm As. This effluent was treated with the air micronanobubble (MNB) generator equipment patented by Dr. Jhonny Valverde Flores. The variables of the pressure and the insufflation time of air as MNB in the effluent with content of the arsenic element were analyzed. A 40% decrease of As was obtained in the effluent. The results indicate that the use of MNB is promising in terms of the reduction of arsenic in solutions with concentrations of the same