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In a world of shrinking habitats and increasing competition for natural resources, potentially dangerous predators bring the challenges of coexisting with wildlife sharply into focus. Through interdisciplinary collaboration among authors trained in the humanities, social sciences, and natural sciences, we reviewed current approaches to mitigating adverse human-predator encounters and devised a vision for future approaches to understanding and mitigating such encounters. Limitations to current approaches to mitigation include too much focus on negative impacts; oversimplified equating of levels of damage with levels of conflict; and unsuccessful technical fixes resulting from failure to engage locals, address hidden costs, or understand cultural (nonscientific) explanations of the causality of attacks. An emerging interdisciplinary literature suggests that to better frame and successfully mitigate negative human-predator relations conservation professionals need to consider dispensing with conflict as the dominant framework for thinking about human-predator encounters; work out what conflicts are really about (they may be human-human conflicts); unravel the historical contexts of particular conflicts; and explore different cultural ways of thinking about animals. The idea of cosmopolitan natures may help conservation professionals think more clearly about human-predator relations in both local and global context. These new perspectives for future research practice include a recommendation for focused interdisciplinary research and the use of new approaches, including human-animal geography, multispecies ethnography, and approaches from the environmental humanities notably environmental history. Managers should think carefully about how they engage with local cultural beliefs about wildlife, work with all parties to agree on what constitutes good evidence, develop processes and methods to mitigate conflicts, and decide how to monitor and evaluate these. Demand for immediate solutions that benefit both conservation and development favors dispute resolution and technical fixes, which obscures important underlying drivers of conflicts. If these drivers are not considered, well-intentioned efforts focused on human-wildlife conflicts will fail. En un mundo en el que los hábitats se reducen y la competencia por los recursos naturales incrementa, los depredadores potencialmente peligrosos resaltan pronunciadamente la dificultad de coexistir con la vida silvestre. Por medio de la colaboración interdisciplinaria entre autores preparados en las humanidades, las ciencias sociales y las ciencias naturales revisamos las estrategias actuales para mitigar los encuentros adversos entre depredadores y humanos y diseñamos una visión para estrategias futuras para entender y mitigar dichos encuentros. Las limitaciones de las estrategias actuales para la mitigación incluyen demasiado enfoque sobre los impactos negativos; la equiparación demasiado simplificada de los niveles de daño con los niveles del conflicto; y los arreglos técnicos infructuosos que resultan del fracaso por involucrar a los locales, hablar sobre los costos ocultos o entender las explicaciones culturales (no científicas) de la causalidad de los ataques. La literatura interdisciplinaria emergente sugiere que para enmarcar de mejor manera y mitigar exitosamente las relaciones negativas entre humanos y depredadores, los profesionales de la conservación necesitan considerar dispensar el conflicto como el marco de trabajo dominante para pensar sobre los encuentros entre humanos y depredadores; descifrar de qué se tratan realmente los conflictos (pueden ser conflictos humano - humano); aclarar los contextos históricos de conflictos particulares; y explorar las diferentes formas culturales de pensar sobre los animales. La idea de naturalezas cosmopolitas puede ayudar a los profesionales de la conservación a pensar de manera más clara sobre las relaciones humano - depredador en el contexto global y en el local. Estas nuevas perspectivas para la futura investigación de la práctica incluyen una recomendación para la investigación interdisciplinaria enfocada y el uso de nuevas estrategias, incluidas la geografía humano - animal, la etnografía de varias especies y estrategias de las humanidades ambientales, notablemente la historia ambiental. Los manejadores deberían pensar cuidadosamente sobre cómo se involucran con las creencias de los locales acerca de la vida silvestre, trabajar con todos los actores para acordar qué constituye una buena evidencia, desarrollar procesos y métodos para mitigar los conflictos, y decidir cómo monitorear y evaluarlos. La demanda por soluciones inmediatas que benefician tanto a la conservación como al desarrollo favorece a la resolución de disputas y a los arreglos técnicos, lo que hace a un lado a importantes conductores subyacentes de los conflictos. Si no son considerados estos conductores, los esfuerzos bien intencionados enfocados en los conflictos humano - vida silvestre fracasarán.

An ion exchange resin was synthesized by using a natural polyelectrolyte, sodium alginate, and barium ion as a cross-linker reagent. Resin was characterized by TGA and SEM. Equilibrium and kinetic experiments of Pb 2+ , Hg 2+ , Ni 2+ , Co 2+ , Fe 2+ , and Fe 3+ ions uptake by barium alginate beads were carried out in batch-type experiments under different values of pH. The removal efficiency increases with increasing pH. The uptake of metal ions occurs rapidly in the first hour. Maximum retention capacity was also determined being Fe(II) > Fe(III) > Co(II) > Ni(II) > Pb(II) > Hg(II) in mmol/g dry beads basis. Elution from the loaded resins at maximum capacity was studied by using HCl and HNO 3 as eluents at different concentrations.

In this article, we studied the sorption properties of poly(ethyleneimine) coated on silica gel for metal ions with impact on the environment, such as Zn(II), Cd(II), Hg(II), and Pb(II). The experiments were carried out by batch procedure and the effects of pH, concentration, and temperature were evaluated. In addition, the selectivity was studied for binary, ternary, and quaternary metal ion mixtures. Mercury and lead showed promising results, achieving higher than 65% of sorption after only 1 h of contact. Under competitive conditions, resin presented high selectivity toward Hg(II) reaching 91 and 87% of retention respect to total amount of ions for binary and quaternary mixtures, respectively. The effect of time on Pb(II) and Hg(II) sorption was studied by batch procedure and the experimental data were adjusted to pseudo-first-order, pseudo-second-order, and intra-particle diffusion models. Pseudo-second-order model presented good agreement for Pb(II) sorption, while pseudo-first-order model fits better to Hg(II) sorption. Intra-particle diffusion model showed that sorption process is controlled mainly by film diffusion.

The resin poly(acrylamide- co -methacrylic acid) P(AAm- co -MA) by radical polymerization was synthesized and its metal ion binding was studied using the batch and column equilibrium procedures for: Cd(II), Zn(II), Pb(II), Hg(II), Al(III), and Cr(III). Experiments were carried out at different pH, metal ion concentration, temperature, and contact time. The resin’s retention behavior was influenced by the pH. The highest retention 91% (0.248 mmol/g, 6.7 mg/g) was achieved at pH 5 for Al(III), and 87% (0.265 mmol/g, 54.9 mg/g) for Pb(II). For Hg(II), the yield was 85% (0.318 mmol/g, 63.7 mg/g) at pH 2. The metal-ion retention properties were dependent on the polymer/metal ion ratio. Under competitive conditions of Pb(II), Hg(II), and Al(III), the resin showed a higher retention of Hg(II), allowing the selective separation of this metal.

To evaluate the effect of patterned, frequency-modulated oro-somatosensory stimulation on time to full oral feeds in preterm infants born 26-30 weeks gestation. This is a multicenter randomized controlled trial. The experimental group (n = 109) received patterned, frequency-modulated oral stimulation via the NTrainer system through a pulsatile pacifier and the control group (n = 101) received a non-pulsatile pacifier. Intent-to-treat analysis (n = 210) was performed to compare the experimental and control groups and the outcomes were analyzed using generalized estimating equations. Time-to-event analyses for time to reach full oral feeds and length of hospital stay were conducted using Cox proportional hazards models. The experimental group had reduction in time to full oral feeds compared to the control group (-4.1 days, HR 1.37 (1.03, 1.82) p = 0.03). In the 29-30 weeks subgroup, infants in the experimental group had a significant reduction in time to discharge (-10 days, HR 1.87 (1.23, 2.84) p < 0.01). This difference was not observed in the 26-28 weeks subgroup. There was no difference in growth, mortality or morbidities between the two groups. Patterned, frequency-modulated oro-somatosensory stimulation improves feeding development in premature infants and reduces their length of hospitalization. ClinicalTrials.gov NCT01158391.

A novel series of copolymer hydrogels of 2-(dimethylamino)ethylacrylate (DMAEA)/2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) were prepared by solution free radical polymerization at different feed monomer mol ratios. The monomer reactivity ratios were determined by Kelen–Tüdös method. According to that, the monomer reactivity ratios for poly(DMAEA- co -AMPS) were r 1  = 0.125 and r 2  = 2.85, (r 1  × r 2  = 0.356). The effect of reaction parameters, including the concentration of cross-linking reagent N , N ′-methylene-bis-acrylamide (MBA) and initiator ammonium persulfate (APS), the monomer concentration, pH, temperature, salt solutions, and solvent polarity on the water absorption have been also studied. The hydrogels achieved water-absorption values of 430 g of water/g of xerogel for the copolymer 1:2 richest in AMPS moiety. This copolymer is also very stable to the temperature effect. The optimum pH for the copolymers is 7. Aqueous solutions of the copolymers showed lower critical solution temperature behaviour (LCST). The phase transition temperatures of aqueous solutions of these copolymer increased with increasing of hydrophilic AMPS unit content in the copolymers. The glass transition temperature (Tg) of hydrogels showed a decrease by increasing of comonomer DMAEA content.

SummaryUsing capillary zone electrophoresis has made characterizations of different copolymers obtained via zwitterionic polymerization. Results demonstrate that this technique is able to put into evidence the molecular heterogeneity of the different copolymers. Analyses were performed in less than 10 minutes using a borate buffer. To our knowledge this the first time that free-zone capillary electrophoresis has been applied to the characterization of copolymers systems below the oligomer range obtained via zwitterion polymerization.

SummaryFive copolymers from N-(hydroxyethyl)ethyleneimine as nucleophilic monomer and phenylsuccinic anhydride (PhSAn) as electrophilic monomer, were synthesized according to the spontaneous copolymerization concept. These copolymers were characterized by elemental analysis, FT-IR, 1H-NMR, and 13C-NMR spectroscopy. The copolymer composition determined from the 1H-NMR spectra showed that the copolymers are not alternating. According to all the data, it was suggested a copolymer structure which includes ester and anhydride bonds. The molecular weights determined by vapor pressure osmometry ranged between 5.100 and 6.100 g/mol.

SummaryThe polymerization of isatoic anhydride (electrophilic monomer) with N-(2-hydroxyethyl)ethyleneimine (nucleophilic monomer) was studied in the absence of added initiator at different feed monomer concentrations, temperature, and time of copolymerization. The copolymers were characterized by FT-IR, 1H-NMR and 13C-NMR spectroscopy, and TGA. Based on spectroscopic data and copolymer composition, a copolymer structure was suggested.

SUMMARYPoly(N-vinylpyrrolidone) (PVP) was investigated as a novel extracting agent. The metal ion extraction properties for Cu(II), Co(II), Ni(II), Cd(II), Zn(II), Pb(II), Hg(II), Cr(III) and Fe(III) were investigated using the liquid-liquid solvent extraction technique (bath method). The metal ion interactions with the polymer were determined as a function of the pH as well as the kinetic characteristic and stripping.For copper ions pH 4 was the optimum extracting pH value, and the 2M hydrochloride acid was better than nitric acid as a stripping agent.