Non-L\'evy mobility patterns of Mexican Me'Phaa peasants searching for fuelwood

We measured mobility patterns that describe walking trajectories of individual Me'Phaa peasants searching and collecting fuelwood in the forests of "La Monta\~na de Guerrero" in Mexico. These one-day excursions typically follow a mixed pattern of nearly-constant steps when individuals displace from their homes towards potential collecting sites and a mixed pattern of steps of different lengths when actually searching for fallen wood in the forest. Displacements in the searching phase seem not to be compatible with L\'evy flights described by power-laws with optimal scaling exponents. These findings however can be interpreted in the light of deterministic searching on heavily degraded landscapes where the interaction of the individuals with their scarce environment produces alternative searching strategies than the expected L\'evy flights. These results have important implications for future management and restoration of degraded forests and the improvement of the ecological services they may provide to their inhabitants.Comment: 15 pages, 4 figures. First version submitted to Human Ecology. The final publication will be available at http://www.springerlink.co

Use of five probiotic strains to determine sensitivity in vitro on pathogenic bacteria growth isolated from sick fishes

ABSTRACT Ornamental aquaculture is an activity in clear economic growth, both globally and in Mexico where the development is particularly relevant to freshwater species. Infectious diseases produced by fungus, bacteria and virus are considered one of the principal limitations during the productive process. Between implemented strategies for reduction of antibiotic use, which are "living microorganisms that confer a health benefit to the host if they are given in adequate quantities"; lactic acid bacteria and yeast are among the most common used microorganism in aquaculture. This investigation, prove the effect of isolated probiotic bacteria from the digestive tract of healthy fish, belonging to specie: Bacillus sp., Bacillus laterosporus, Bacillus subtilis, Lactobacillus sp, and Lactococcus lactis, at different dilutions (10 9 ,10 8 , 10 7 ,10 6 , 10 5 and 10 4 ) in vitro growth of pathogenic bacteria: Citrobacter freundii, Enterobacter sakasakii, Klebsiella oxytoca, Proteus vulgaris, and Vibrio fluvialis, isolated from kidney of sick fish, cultured and purified through successive inoculations and identificated by the amplification of gene 16S of rRNA (PCR) using universal primers 8 for. (5'-AGACTTTGATCATGGCTCAG-3') and 1492 rev. (5'-TACGGCTACCTTGTTACGACTT-3') and comparison with GENEBANK sequences base. Probiotic strains were previously isolated from the digestive tract of different healthy fish in the laboratory. In order to perform in vitro challenge tests, pathogenic strains were inoculated three times each in BHI agar boxes at a concentration of 1x10 7 CFU mL -1 and subsequently using the well diffusion method, 70 µL from a suspension with each of the probiotic strains were added. Agar boxes were incubated 24 h at 30ºC to observe the formation of inhibition halos. Obtained values from inhibition halos were transformed to qualitative data with the following premise: halo diameter < 2.0 mm negative effect; halo diameter > 2.0 mm positive effect. In this study, it was determined that probiotic strains B. subtilis was the one that gave better results to inhibit the growth of pathogenic bacteria P. vulgaris, E. sakazakii, V. fluvialis, K. oxytoca and C. freundii in most of used dilutions. Making it a strain with high potential in aquaculture. Key words: Growth, halos, probiotics, bacteria, sensibility. RESUMEN La acuicultura de especies ornamentales es una actividad económica en franco crecimiento, tanto a nivel mundial como en México, en donde tiene particular desarrollo lo correspondiente a especies dulceacuícolas. Las enfermedades infeccionas producidas por hongos, bacterias y virus, están consideradas una de las limitantes principales durante el proceso productivo. Entre las estrategias implementadas para disminuir el uso de antibióticos para el control de patógenos, se encuentra el control biológico mediante el uso de organismos probióticos, los cuales son "microorganismos vivos los cuales, administrados en cantidades adecuadas, confieren un beneficio en la salud del hospedador"; entre los de uso más común en acuicultura se encuentran las lactobacterias y las levaduras. En el presente trabajo, se probó el efecto de bacterias probióticas aisladas del tracto digestivo de peces sanos, pertenecientes a las especies: Bacillus sp., Bacillus laterosporus, Bacillus subtilis, Lactobacillus sp, y Lactococcus lactis, a diferentes diluciones (10 9 ,10 8 , 10 7 ,10 6 , 10 5 y 10 4 ) en el crecimiento in vitro de las bacterias patógenas: Citrobacter freundii, Enterobacter sakasakii, Klebsiella oxytoca, Proteus vulgaris y Vibrio fluvialis, aisladas del riñón de peces enfermos, cultivadas y purificadas a través de resiembras sucesivas e identificadas mediante la amplificación del gen 16S del ARNr (PCR) utilizando los primers universales 8 for. 24 AGACTTTGATCATGGCTCAG-3') y 1492 rev. (5'-TACGGCTACCTTGTTACGACTT-3') y su comparación con la base de secuencias GENEBANK. Las cepas probióticos fueron aisladas previamente del tracto intestinal de diversos peces sanos en el laboratorio. Para llevar a cabo las pruebas de desafío in vitro, las cepas patógenas se sembraron por triplicado en cajas de agar BHI a una concentración de 1x10 7 UFC mL -1 y posteriormente, utilizando el método de difusión en pozos, se adicionaran 70 µL de una suspensión con cada una de las cepas probióticas Las placas se incubaron durante 24 h a 30ºC para observar la formación de halos de inhibición. Los valores obtenidos de los halos de inhibición fueron transformados a datos cualitativos con la siguiente premisa: diámetro halo < 2.0 mm efecto negativo; diámetro de halo > 2.0 mm efecto positivo. En este estudio, se determinó que la cepas probiótica B. subtilis fue la que dio mejores resultados al inhibir el crecimiento de las bacterias patógenas P. vulgaris, E. sakazakii, V. fluvialis, K. oxytoca y C. freundii en la mayoría de las diluciones utilizadas. Por lo que es una cepa con alto potencial en acuicultura

Inverse Association between Dietary Iron Intake and Gastric Cancer: A Pooled Analysis of Case‐Control Studies of the Stop Consortium

Background: Inconsistent findings have been reported regarding the relationship between dietary iron intake and the risk of gastric cancer (GC). Methods: We pooled data from 11 case‐control studies from the Stomach Cancer Pooling (StoP) Project. Total dietary iron intake was derived from food frequency questionnaires combined with national nutritional tables. We derived the odds ratios (ORs) and 95% confidence intervals (CIs) for quartiles of dietary iron through multivariable unconditional logistic regression models. Secondary analyses stratified by sex, smoking status, caloric intake, anatomical subsite and histological type were performed. Results: Among 4658 cases and 12247 controls, dietary iron intake was inversely associated with GC (per quartile OR 0.88; 95% CI: 0.83–0.93). Results were similar between cardia (OR = 0.85, 95% CI = 0.77–0.94) and non‐cardia GC (OR = 0.87, 95% CI = 0.81–0.94), and for diffuse (OR = 0.79, 95% CI = 0.69–0.89) and intestinal type (OR = 0.88, 95% CI = 0.79–0.98). Iron intake exerted an independent effect from that of smoking and salt intake. Additional adjustment by meat and fruit/vegetable intake did not alter the results. Conclusions: Dietary iron is inversely related to GC, with no difference by subsite or histological type. While the results should be interpreted with caution, they provide evidence against a direct effect of iron in gastric carcinogenesis. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.This study was supported by the Fondazione AIRC per la Ricerca sul Cancro, Project no. 21378 (Investigator Grant). The Unidade de Investigação em Epidemiologia—Instituto de Saúde Pública da Universidade do Porto (EPIUnit; UIDB/04750/2020) and the Laboratório para a Investigação Integrativa e Translacional em Saúde Populacional (ITR; LA/P/0064/2020) were funded by the Foundation for Science and Technology—FCT (Portuguese Ministry of Science, Technology and Higher Education). SM was supported by the project “NEON‐PC—Neuro‐oncological complications of prostate cancer: longitudinal study of cognitive decline” (POCI‐01‐0145‐FEDER‐032358; ref. PTDC/SAU‐EPI/32358/2017), which is funded by FEDER through the Operational Programme competitiveness and Internationalization, and national funding from FCT and the EPIUnit—Junior Research—Prog Financing (UIDP/04750/2020). The authors thank the European Cancer Prevention (ECP) Organization for providing support for the StoP Project meetings and all MCC‐Spain study collaborators (CIBERESP, ISCIII, ISGlobal, ICO, University of Huelva, University of Oviedo, University of Cantabria, ibs.Granada, Instituto Salud Pública de Navarra, FISABIO, Murcia Regional Health Authority and cols)

Properties of Graphene: A Theoretical Perspective

In this review, we provide an in-depth description of the physics of monolayer and bilayer graphene from a theorist's perspective. We discuss the physical properties of graphene in an external magnetic field, reflecting the chiral nature of the quasiparticles near the Dirac point with a Landau level at zero energy. We address the unique integer quantum Hall effects, the role of electron correlations, and the recent observation of the fractional quantum Hall effect in the monolayer graphene. The quantum Hall effect in bilayer graphene is fundamentally different from that of a monolayer, reflecting the unique band structure of this system. The theory of transport in the absence of an external magnetic field is discussed in detail, along with the role of disorder studied in various theoretical models. We highlight the differences and similarities between monolayer and bilayer graphene, and focus on thermodynamic properties such as the compressibility, the plasmon spectra, the weak localization correction, quantum Hall effect, and optical properties. Confinement of electrons in graphene is nontrivial due to Klein tunneling. We review various theoretical and experimental studies of quantum confined structures made from graphene. The band structure of graphene nanoribbons and the role of the sublattice symmetry, edge geometry and the size of the nanoribbon on the electronic and magnetic properties are very active areas of research, and a detailed review of these topics is presented. Also, the effects of substrate interactions, adsorbed atoms, lattice defects and doping on the band structure of finite-sized graphene systems are discussed. We also include a brief description of graphane -- gapped material obtained from graphene by attaching hydrogen atoms to each carbon atom in the lattice.Comment: 189 pages. submitted in Advances in Physic

P-loop mutations and novel therapeutic approaches for imatinib failures in chronic myeloid leukemia

Imatinib was the first BCR-ABL-targeted agent approved for the treatment of patients with chronic myeloid leukemia (CML) and confers significant benefit for most patients; however, a substantial number of patients are either initially refractory or develop resistance. Point mutations within the ABL kinase domain of the BCR-ABL fusion protein are a major underlying cause of resistance. Of the known imatinib-resistant mutations, the most frequently occurring involve the ATP-binding loop (P-loop). In vitro evidence has suggested that these mutations are more oncogenic with respect to other mutations and wild type BCR-ABL. Dasatinib and nilotinib have been approved for second-line treatment of patients with CML who demonstrate resistance (or intolerance) to imatinib. Both agents have marked activity in patients resistant to imatinib; however, they have differential activity against certain mutations, including those of the P-loop. Data from clinical trials suggest that dasatinib may be more effective vs. nilotinib for treating patients harboring P-loop mutations. Other mutations that are differentially sensitive to the second-line tyrosine kinase inhibitors (TKIs) include F317L and F359I/V, which are more sensitive to nilotinib and dasatinib, respectively. P-loop status in patients with CML and the potency of TKIs against P-loop mutations are key determinants for prognosis and response to treatment. This communication reviews the clinical importance of P-loop mutations and the efficacy of the currently available TKIs against them