Welding-base metal investigation Final report, 27 Jun. 1964 - 28 Jul. 1965

Weld defects associated with aluminum alloys - monitoring weld shielding gas purit

VOLUMEN 20, NÚMERO 35 (1991)

PROPUESTA DE UNIFICACIÓN PARA LA NOMENCLATURA ESTRATIGRÁFICA DEL TERCIARIO DEL VALLE DEL CAUCA Y DEL CAUCA. Padilla, L. E.CARÁCTER CÍCLICO DEL TERCIARIO HULLERO DEL VALLE DEL CAUCA Y CAUCA. Padilla, L. E.LINEAMIENTOS DE DIRECCIÓN NORESTE-SURESTE EN LOS DEPARTAMENTOS DE SANTANDER Y NORTE DE SANTANDER, COLOMBIA. Ujueta, L. G.LA DUNITA DE MEDELLÍN Y SUS RELACIONES ESTRUCTURALES CON EL BASAMENTO METAMÓRFICO E INTRUSIVO DE LA CORDILLERA CENTRAL, DEPARTAMENTO DE ANTIOQUIA. Kammer, A

VOLUMEN 20, NÚMERO 35 (1991)

PROPUESTA DE UNIFICACIÓN PARA LA NOMENCLATURA ESTRATIGRÁFICA DEL TERCIARIO DEL VALLE DEL CAUCA Y DEL CAUCA. Padilla, L. E.CARÁCTER CÍCLICO DEL TERCIARIO HULLERO DEL VALLE DEL CAUCA Y CAUCA. Padilla, L. E.LINEAMIENTOS DE DIRECCIÓN NORESTE-SURESTE EN LOS DEPARTAMENTOS DE SANTANDER Y NORTE DE SANTANDER, COLOMBIA. Ujueta, L. G.LA DUNITA DE MEDELLÍN Y SUS RELACIONES ESTRUCTURALES CON EL BASAMENTO METAMÓRFICO E INTRUSIVO DE LA CORDILLERA CENTRAL, DEPARTAMENTO DE ANTIOQUIA. Kammer, A

Simultaneous Embeddings with Few Bends and Crossings

A simultaneous embedding with fixed edges (SEFE) of two planar graphs $R$ and $B$ is a pair of plane drawings of $R$ and $B$ that coincide when restricted to the common vertices and edges of $R$ and $B$. We show that whenever $R$ and $B$ admit a SEFE, they also admit a SEFE in which every edge is a polygonal curve with few bends and every pair of edges has few crossings. Specifically: (1) if $R$ and $B$ are trees then one bend per edge and four crossings per edge pair suffice (and one bend per edge is sometimes necessary), (2) if $R$ is a planar graph and $B$ is a tree then six bends per edge and eight crossings per edge pair suffice, and (3) if $R$ and $B$ are planar graphs then six bends per edge and sixteen crossings per edge pair suffice. Our results improve on a paper by Grilli et al. (GD'14), which proves that nine bends per edge suffice, and on a paper by Chan et al. (GD'14), which proves that twenty-four crossings per edge pair suffice.Comment: Full version of the paper "Simultaneous Embeddings with Few Bends and Crossings" accepted at GD '1

2-Cyano-1-methyl­pyridinium nitrate

In the title compound, C7H7N2 +·NO3 −, all atoms except the methyl H atoms lie on a crystallographic mirror plane. The inter­layer distance, including that between aligned N atoms from alternating cations and anions in adjacent layers, is exceptionally short at 3.055 (1) Å. Two-dimensional C—H⋯O hydrogen-bonded networks link cations to anions, while C—H⋯N inter­actions link cations within each layer. Anion–π inter­actions with the cations assist in binding the layers together

A chronometric exploration of high-resolution ‘sensitive TMS masking’ effects on subjective and objective measures of vision

Transcranial magnetic stimulation (TMS) can induce masking by interfering with ongoing neural activity in early visual cortex. Previous work has explored the chronometry of occipital involvement in vision by using single pulses of TMS with high temporal resolution. However, conventionally TMS intensities have been high and the only measure used to evaluate masking was objective in nature. Recent studies have begun to incorporate subjective measures of vision, alongside objective ones. The current study goes beyond previous work in two regards. First, we explored both objective vision (an orientation discrimination task) and subjective vision (a stimulus visibility rating on a four-point scale), across a wide range of time windows with high temporal resolution. Second, we used a very sensitive TMS-masking paradigm: stimulation was at relatively low TMS intensities, with a figure-8 coil, and the small stimulus was difficult to discriminate already at baseline level. We hypothesized that this should increase the effective temporal resolution of our paradigm. Perhaps for this reason, we are able to report a rather interesting masking curve. Within the classical-masking time window, previously reported to encompass broad SOAs anywhere between 60 and 120 ms, we report not one, but at least two dips in objective performance, with no masking in-between. The subjective measure of vision did not mirror this pattern. These preliminary data from our exploratory design suggest that, with sensitive TMS masking, we might be able to reveal visual processes in early visual cortex previously unreported

Characteristics of Welding Fume Aerosol Investigated in Three Swedish Workshops

Potentially high human exposures to nanometer sized airborne particles occur due to welding and other thermal processes in industrial environments. Detailed field measurements of physical and chemical particle characteristics were performed in three work-shops in Sweden. Measurements were performed both in the plume 5-20 cm above the welding point and in the background air (more than 5 m away from the nearest known particle source). Particle number and mass concentrations were measured on-line. A low pressure impactor was used for size-resolved chemical particle composition. The in-plume measurements generated the chemical signatures for different welding processes. These signatures were then used to identify contributions from various processes to the particle concentrations in different size classes. The background number and mass concentrations increased by more than an order of magnitude during intense activities in the work-shops compared to low activities during breaks