A 3D Printed Toolbox for Opto-Mechanical Components

Nowadays is very common to find headlines in the media where it is stated that 3D printing is a technology called to change our lives in the near future. For many authors, we are living in times of a third industrial revolution. Howerver, we are currently in a stage of development where the use of 3D printing is advantageous over other manufacturing technologies only in rare scenarios. Fortunately, scientific research is one of them. Here we present the development of a set of opto-mechanical components that can be built easily using a 3D printer based on Fused Filament Fabrication (FFF) and parts that can be found on any hardware store. The components of the set presented here are highly customizable, low-cost, require a short time to be fabricated and offer a performance that compares favorably with respect to low-end commercial alternatives.Comment: 9 pages, 9 figure

Management of the Rice Tungro Virus Vector \u3ci\u3eNephotettix virescens\u3c/i\u3e (Homoptera: Cicadellidae) with Controlled-Release Formulations of Carbofuran

Field trials were conducted in lowland flooded rice in the Philippines to evaluate a number of carbofuran controlled-release formulations in comparison with commercial formulations. The test formulations were based on a biodegradable matrix of pine kraft lignin and were used as granules of different sizes and also in the form of small strips. The release rates were assessed under field conditions by bioassaying rice plants in the field, using adult rice green leafhopper, Nephotettix virescens Distant. The lignin formulations with a high level of active ingredient (15–45% by weight) gave as good or better control than the commercial 3% granules in tests based on three application techniques: broadcast into the floodwater, soil incorporation, and root zone injection. The improvements in control levels of green leafhoppers were most marked with soil incorporation and root zone application. The best lignin-based formulation reduced levels of tungro virus infection from 23% for a conventional flowable carbofuran formulation to 1.0% at an application rate of 0.5 kg (AI)/ha. At the same rate, the grain yield was increased from 3.56 t/ha to 5.5 t/ha, using the controlled-released formulation

Energy Efficiency of Hybrid-Power HetNets: A Population-like Games Approach

In this paper, a distributed control scheme based on population games is proposed. The controller is in charge of dealing with the energy consumption problem in a Heterogeneous Cellular Network (HetNet) powered by hybrid energy sources (grid and renewable energy) while guaranteeing appropriate quality of service (QoS) level at the same time. Unlike the conventional approach in population games, it considers both atomicity and non-anonymity. Simulation results show that the proposed population-games approach reduces grid consumption by up to about 12% compared to the traditional best-signal level association policy.U.S. Air Force Office of Scientific Research FA9550-17-1-0259Ministerio de Cultura y Deporte DPI2016-76493-C3-3-RMinisterio de Economía y Empresa DPI2017-86918-

Synthesis, Characterization, Crystal Structure, and Biological Studies of a Cadmium(II) Complex with a Tridentate Ligand 4′-Chloro-2,2′:6′,2′′-Terpyridine

A new Cd(II) complex with the ligand 4′-chloro-2,2′6′,2′′-terpyridine (Cltpy), [Cd(Cltpy)(I)2], has been synthesized and characterized by CHN elemental analysis, 1H-NMR, 13C-NMR, and IR spectroscopy and structurally analyzed by X-ray single-crystal diffraction. The single-crystal X-ray analyses show that the coordination number in complex is five with three terpyridine (Cltpy) N-donor atoms and two iodine atoms. The antibacterial activities of Cltpy and its Cd(II) complex are tested against different bacteria

From residue coevolution to protein conformational ensembles and functional dynamics

The analysis of evolutionary amino acid correlations has recently attracted a surge of renewed interest, also due to their successful use in de novo protein native structure prediction. However, many aspects of protein function, such as substrate binding and product release in enzymatic activity, can be fully understood only in terms of an equilibrium ensemble of alternative structures, rather than a single static structure. In this paper we combine coevolutionary data and molecular dynamics simulations to study protein conformational heterogeneity. To that end, we adapt the Boltzmann-learning algorithm to the analysis of homologous protein sequences and develop a coarse-grained protein model specifically tailored to convert the resulting contact predictions to a protein structural ensemble. By means of exhaustive sampling simulations, we analyze the set of conformations that are consistent with the observed residue correlations for a set of representative protein domains, showing that (i) the most representative structure is consistent with the experimental fold and (ii) the various regions of the sequence display different stability, related to multiple biologically relevant conformations and to the cooperativity of the coevolving pairs. Moreover, we show that the proposed protocol is able to reproduce the essential features of a protein folding mechanism as well as to account for regions involved in conformational transitions through the correct sampling of the involved conformers

Carl Djerassi: “In memoriam”. Pionero de la creación del “anticonceptivo oral” y hombre polifacético

ResumenCarl Djerassi nació en Viena en 1923 y emigró a New York en 1939 donde escribió una carta a Eleanor Roosevelt solicitando un apoyo para continuar sus estudios, graduándose en química en 1942 y obteniendo su doctorado en química en la Universidad de Wisconsin en 1945. Sintetizó el esteroide básico del “anticonceptivo oral”, genéricamente conocido como noretisterona. Desde el siglo pasado se sabía que la administración parenteral de estrógenos y progesterona inhibía la ovulación, pero resultaba de un costo muy elevado. Jorge Rosenkranz invitó a Djerassi a incorporarse a Syntex para buscar la síntesis de progesterona, quienes junto con Luis E. Miramontes emplearon el esteroide esencial obtenido del barbasco descubierto por Rusell E. Marker. De esta manera se consiguió industrializar el anticonceptivo hormonal oral conocido trivialmente como la “píldora”.Djerassi se podría considerar como un conspicuo químico, biólogo y sociólogo; incursionó en la literatura, fue coleccionista de arte y benefactor de artistas. Fue presidente de Syntex en México y en Palo Alto. Falleció el 30 de enero de 2015 a la edad de 91 años en San Francisco California.AbstractCarl Djerassi (Vienna, 1923) immigrated to New York in 1939, where he wrote to Eleanor Roosevelt requesting funding to continue his studies, graduating in chemistry in 1942, and acquiring a doctorate in chemistry at the University of Wisconsin in 1945. He synthesised the basic “oral contraceptive” steroid, known generically as norethisterone. Since the preceding century parenteral estrogens and progesterone had been known to inhibit ovulation, but producing them was very expensive. Jorge Rosenkranz invited Djerassi to join Syntex to work on progesterone synthesis; together with Luis E. Miramontes, the researchers used the essential steroid from barbasco [a Mexican yam] discovered by Russell E. Marker to make it possible to industrialise the oral hormonal contraceptive commonly known as “the pill”.Djerassi could be considered as a distinguished chemist, biologist and sociologist, who also pursued literature and was an art collector and artists’ benefactor. Past president of Syntex in Mexico and in Palo Alto, he died on 30 January 2015 at the age of 91 in San Francisco, California