Interactions of technology and society: Impacts of improved airtransport. A study of airports at the grass roots

The feasibility of applying a particular conception of technology and social change to specific examples of technological development was investigated. The social and economic effects of improved airport capabilities on rural communities were examined. Factors which led to the successful implementation of a plan to construct sixty small airports in Ohio are explored and implications derived for forming public policies, evaluating air transportation development, and assessing technology

A robust enhancement to the Clarke-Wright savings algorithm

We address the Clarke and Wright (CW) savings algorithm proposed for the Capacitated Vehicle Routing Problem (CVRP). We first consider a recent enhancement which uses the put first larger items idea originally proposed for the bin packing problem and show that the conflicting idea of putting smaller items first has a comparable performance. Next, we propose a robust enhancement to the CW savings formulation. The proposed formulation is normalized to efficiently solve different problems, independent from the measurement units and parameter intervals. To test the performance of the proposed savings function, we conduct an extensive computational study on a large set of well-known instances from the literature. Our results show that the proposed savings function provides shorter distances in the majority of the instances and the average performance is significantly better than previously presented enhancements

Dominant BIN1-related centronuclear myopathy (CNM) revealed by lower limb myalgia and moderate CK elevation

We report a BIN1-related CNM family with unusual clinical phenotype. The proband, a 56-year-old man suffered of lower limbs myalgia since the age of 52. Clinical examination showed short stature, mild symmetric eyelid ptosis without ophthalmoplegia, scapular winging and Achilles tendon retraction. A muscle weakness was not noted. CK levels were up to 350 UI/L. Deltoid muscle biopsy showed nuclear centralization and clustering, deep sarcolemmal invaginations and type 1 fiber hypotrophy. Whole body MRI revealed fatty infiltration of posterior legs compartments, lumbar paraspinal and serratus muscles. Myotonic dystrophy type1 and 2, Pompe disease and MTM1 and DNM2-related CNM were ruled out. By sequencing BIN1, we identified a heterozygous pathogenic mutation [c.107C > A (p.A36E)], and we demonstrate that the mutation strongly impairs the membrane tubulation property of the protein. One affected sister carried the same mutation. Her clinical examination and muscle MRI revealed a similar phenotype. Our findings expand the clinical and genetic spectrum of the autosomal dominant CNM associated with BIN1 mutations

The Mean Absorption Line Spectra of a Selection of Luminous z~6 Lyman Break Galaxies

We examine the absorption-line spectra of a sample of 31 luminous (${M}_{\mathrm{UV}}\simeq -23$) Lyman break galaxies at redshift z sime 6 using data taken with the FOCAS and OSIRIS spectrographs on the Subaru and GTC telescopes. For two of these sources we present longer exposure data taken at higher spectral resolutions from ESO's X-shooter spectrograph. Using these data, we demonstrate the practicality of stacking our lower-resolution data to measure the depth of various interstellar and stellar absorption lines to probe the covering fraction of low-ionization gas and the gas phase and stellar metallicities near the end of the era of cosmic reionization. From maximum absorption-line depths of Si ii λ1260 and C ii λ1334, we infer a mean covering fraction of ≥0.85 ± 0.16 for our sample. This is larger than that determined using similar methods for lower-luminosity galaxies at slightly lower redshifts, suggesting that the most luminous galaxies appear to have a lower escape fraction than fainter galaxies, and therefore may not play a prominent role in concluding reionization. Using various interstellar absorption lines we deduce gas-phase metallicities close to solar, indicative of substantial early enrichment. Using selected stellar absorption lines, we model our spectra with a range of metallicities using techniques successfully employed at lower redshift and deduce a stellar metallicity of ${0.4}_{-0.1}^{+0.3}$ solar, consistent with the stellar mass—stellar metallicity relation recently found at z ~ 3–5. We discuss the implications of these metallicity estimates for the typical ages of our luminous galaxies and conclude our results imply initial star formation at redshifts z ~ 10, consistent with independent analyses of earlier objects

Impacts of misalignment effects on the Muon Spectrometer Performance

The ATLAS detector, currently being installed at CERN, is designed to exploit the full potential of the LHC, identifying and providing highly accurate energy and momentum measurements of particles emerging from the LHC protonproton collisions with a centre-of-mass energy at 14 TeV, starting in 2007. High-momentum final-state muons are among the most promising signatures at the LHC, thanks to a high-resolution Muon Spectrometer with standalone triggering and momentum measurement. As well known, muons interact primarily trough their electromagnetic charge, but since they are 200 times more massive than the electrons they are less affected by the electric fields of the nuclei they encounter. Muons with an energy of more than a few GeV penetrate the calorimeter and can reach the Muon Spectrometer, which consists out of more than 1.200 single drift-tubes chambers. The correct alignment of the ATLAS Muon Spectrometer is crucial to ensure its design performance. This note documents the first attempt at using various misaligned Muonspectrometer layouts to study their impacts Muon Spectrometer performance

Environment of the submillimeter-bright massive starburst HFLS3 at z∼6.34

We describe the search for Lyman break galaxies (LBGs) near the submillimeter-bright starburst galaxy HFLS3 at z = 6.34 and a study on the environment of this massive galaxy during the end of reionization. We performed two independent selections of LBGs on images obtained with the Gran Telescopio Canarias (GTC) and the Hubble Space Telescope (HST) by combining nondetections in bands blueward of the Lyman break and color selection. A total of 10 objects fulfilling the LBG selection criteria at z > 5.5 were selected over the 4.54 and 55.5 arcmin^2 covered by our HST and GTC images, respectively. The photometric redshift, UV luminosity, and star formation rate of these sources were estimated with models of their spectral energy distribution. These z ~ 6 candidates have physical properties and number densities in agreement with previous results. The UV luminosity function at z ~ 6 and a Voronoi tessellation analysis of this field show no strong evidence for an overdensity of relatively bright objects (m_(F105W) < 25.9) associated with HFLS3. However, the overdensity parameter deduced from this field and the surface density of objects cannot exclude definitively the LBG overdensity hypothesis. Moreover, we identified three faint objects at less than 3'' from HFLS3 with color consistent with those expected for z ~ 6 galaxies. Deeper data are needed to confirm their redshifts and to study their association with HFLS3 and the galaxy merger that may be responsible for the massive starburst

Double-peaked Lyman α emission at z = 6.803: a reionization-era galaxy self-ionizing its local H II bubble

We report the discovery of a double-peaked Lyman α profile in a galaxy at z = 6.803, A370p_z1, in the parallel Frontier Field of Abell 370. The velocity separation between the blue and red peaks of the Lyman α profile (⁠Δ v = 101^{+38}_{-19}(±48)km s^{-1}) suggests an extremely high escape fraction of ionizing photons >59(51) per cent (2σ). The spectral energy distribution indicates a young (50 Myr), star-forming (⁠12 ± 6M_{⊙}yr^{-1}) galaxy with an IRAC excess implying strong [O III] + H β emission. On the basis of the high escape fraction measured, we demonstrate that A370p_z1 was solely capable of creating an ionized bubble sufficiently large to account for the blue component of its Lyman α profile. We discuss whether A370p_z1 may be representative of a larger population of luminous z ≃ 7 double-peaked Lyman α emitting sources with high escape fractions that self-ionized their surroundings without contributions from associated ultraviolet-fainter sources

Diversity-oriented synthesis of a library of substituted tetrahydropyrones using oxidative carbon-hydrogen bond activation and click chemistry

Eighteen (2RS,6RS)-2-(4-methoxyphenyl)-6-(substituted ethyl)dihydro- 2Hpyran-4(3H)ones were synthesized via a DDQ-mediated oxidative carbon-hydrogen bond activation reaction. Fourteen of these tetrahydropyrans were substituted with triazoles readily assembled via azide-alkyne click-chemistry reactions. Examples of a linked benzotriazole and pyrazole motif were also prepared. To complement the structural diversity, the alcohol substrates were obtained from stereoselective reductions of the tetrahydropyrone. This library provides rapid access to structurally diverse non-natural compounds to be screened against a variety of biological targets. © 2011 by the authors

The ALMA Frontier Fields Survey - IV. Lensing-corrected 1.1 mm number counts in Abell 2744, MACSJ0416.1-2403 and MACSJ1149.5+2223

[abridged] Characterizing the number counts of faint, dusty star-forming galaxies is currently a challenge even for deep, high-resolution observations in the FIR-to-mm regime. They are predicted to account for approximately half of the total extragalactic background light at those wavelengths. Searching for dusty star-forming galaxies behind massive galaxy clusters benefits from strong lensing, enhancing their measured emission while increasing spatial resolution. Derived number counts depend, however, on mass reconstruction models that properly constrain these clusters. We estimate the 1.1 mm number counts along the line of sight of three galaxy clusters, i.e. Abell 2744, MACSJ0416.1-2403 and MACSJ1149.5+2223, which are part of the ALMA Frontier Fields Survey. We perform detailed simulations to correct these counts for lensing effects. We use several publicly available lensing models for the galaxy clusters to derive the intrinsic flux densities of our sources. We perform Monte Carlo simulations of the number counts for a detailed treatment of the uncertainties in the magnifications and adopted source redshifts. We find an overall agreement among the number counts derived for the different lens models, despite their systematic variations regarding source magnifications and effective areas. Our number counts span ~2.5 dex in demagnified flux density, from several mJy down to tens of uJy. Our number counts are consistent with recent estimates from deep ALMA observations at a 3$\sigma$ level. Below $\approx$ 0.1 mJy, however, our cumulative counts are lower by $\approx$ 1 dex, suggesting a flattening in the number counts. In our deepest ALMA mosaic, we estimate number counts for intrinsic flux densities $\approx$ 4 times fainter than the rms level. This highlights the potential of probing the sub-10 uJy population in larger samples of galaxy cluster fields with deeper ALMA observations.Comment: 19 pages, 14 figures, 3 tables. Accepted for publication in A&

Resolving Ambiguities in the Inferred Star Formation Histories of Intense [O III] Emitters in the Reionisation Era

Early JWST spectroscopic campaigns have confirmed the presence of strong [O III] line-emitting galaxies in the redshift interval $7<z<9$. Although deduced earlier from Spitzer photometry as indicative of young stellar populations, some studies suggested the relevant photometric excesses attributed to [O III] emission could, in part, be due to Balmer breaks arising from older stars. We demonstrate that this is likely the case by exploiting medium-band near-infrared JWST photometry in the Hubble Ultra Deep Field. We locate a sample of 6 galaxies with redshifts 8.2$<z<$8.6 for which the relevant medium-band filters enables us to separate the contributions of [O III] emission and a Balmer break, thereby breaking earlier degeneracies of interpretation. The technique is particularly valuable since it provides photometric redshifts whose precision, $\Delta\,z\simeq\,\pm0.08$, approaches that of spectroscopic campaigns now underway with JWST. Although some sources are young, a third of our sample have prominent Balmer breaks consistent with stellar ages of $\geq$150 Myr. Our results indicate that even intense [O III] emitters experienced episodes of earlier star formation to $z\sim$10 and beyond, as is now being independently deduced from direct detection of the progenitors of similar systems.Comment: 8 pages, submitted to MNRA