9,654 research outputs found
Characterisation of the cold metal transfer (CMT) process and its application for low dilution cladding
The process characteristics of the synergic cold metal transfer (CMT) process
have been examined for welding aluminium alloy. Utilising a simple backlighting
system and through the arc monitoring the droplet transfer modes were
identified. Whilst the modified short circuit mode was evident for the lower
parameter range, a two part transfer mode based upon a combination of spray and
short circuit transfer was observed for the mid to upper parameter range. The
technology was also explored as a cladding process for applying to ternary
alloyed (Al–Cu–Mg) aluminium plate. This alloy system is known to be susceptible
to solidification cracking when MIG welded using the binary Al-2319 (Al–Cu)
filler wire, this being due to the wide element freezing range of the weld
resulting from mixing with the base material. Utilising this filler, weld
dilution ratios for both CMT and pulsed welding were identified across the
examined parameter range. The CMT process exhibited greater control of dilution
that enabled deposition of a quasi-binary (Al–Cu) layer exhibiting a less crack
susceptible composition. Onto this layer conventional MIG welding could be
applied which could potentially eradicate cracking using a binary fi
Spillovers from the Gridiron: Evidence from Women’s Collegiate Basketball
This paper empirically investigates whether schools with an intercollegiate football team experience greater attendance at women’s basketball games. The empirical question is important because if football increases attendance and hence revenue to other sports then these benefits should be included when considering the net benefits of football. Using a cross-section of 329 Division IA women’s basketball programs from 2005-2006, we find that having a football program corresponds with an increase in per-game attendance of approximately 500 people. This spill-over benefit of having a football team should be credited against the costs of starting and maintaining a football team.NCAA, college sports, positive externalities
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Role of a US-Norway Exchange in Placing Health and Well-Being at the Center of US Prison Reform.
Fungal biofilm resistance
Fungal biofilm infections have become increasingly recognised as a significant clinical problem. One of the major reasons behind this is the impact that these have upon treatment, as antifungal therapy often fails and surgical intervention is required. This places a large financial burden on health care providers. This paper aims to illustrate the importance of fungal biofilms, particularly Candida albicans, and discusses some of the key fungal biofilm resistance mechanisms that include, extracellular matrix (ECM), efflux pump activity, persisters, cell density, overexpression of drug targets, stress responses, and the general physiology of the cell. The paper demonstrates the multifaceted nature of fungal biofilm resistance, which encompasses some of the newest data and ideas in the field
Sound Source Localization in a Multipath Environment Using Convolutional Neural Networks
The propagation of sound in a shallow water environment is characterized by
boundary reflections from the sea surface and sea floor. These reflections
result in multiple (indirect) sound propagation paths, which can degrade the
performance of passive sound source localization methods. This paper proposes
the use of convolutional neural networks (CNNs) for the localization of sources
of broadband acoustic radiated noise (such as motor vessels) in shallow water
multipath environments. It is shown that CNNs operating on cepstrogram and
generalized cross-correlogram inputs are able to more reliably estimate the
instantaneous range and bearing of transiting motor vessels when the source
localization performance of conventional passive ranging methods is degraded.
The ensuing improvement in source localization performance is demonstrated
using real data collected during an at-sea experiment.Comment: 5 pages, 5 figures, Final draft of paper submitted to 2018 IEEE
International Conference on Acoustics, Speech and Signal Processing (ICASSP)
15-20 April 2018 in Calgary, Alberta, Canada. arXiv admin note: text overlap
with arXiv:1612.0350
Prior in vitro exposure to voriconazole confers resistance to amphotericin B in aspergillus fumigatus biofilms
Triazoles are the mainstay of treatment for aspergillosis, although resistance to these antifungal agents may be associated with treatment failure. Refractory infections often necessitate a switch to other antifungal agents, including amphotericin B (AmB), although these infections may not resolve. The aim of this study was to investigate the effect of prior azole exposure on AmB sensitivity in Aspergillus fumigatus biofilms. It was hypothesised that sequential antifungal therapy has the potential to impact adaptive resistance mechanisms. Antifungal sensitivity was determined for each isolate against AmB ± voriconazole (VRZ) exposure by a broth microdilution method and an XTT metabolic assay. To analyse the role of extracellular DNA (eDNA) and Hsp90 activation, sensitivity to AmB ± DNA-digesting enzyme (DNase) or Hsp90 inhibitor [geldanamycin (GDA)] was also tested. Finally, scanning electron microscopy was performed to assess phenotypic changes. The in vitro data revealed that A. fumigatus sensitivity to AmB was decreased when it was tested in combination with VRZ. In addition, a two- to four-fold decreased sensitivity to AmB was recorded against VRZ-exposed germlings compared with controls. It was also shown that depletion of eDNA by DNase treatment enhanced AmB activity against VRZ-exposed cells by eight-fold, which visually could be explained by destabilisation of the biofilm when examined microscopically. Pharmacological inhibition of Hsp90 by GDA significantly improved biofilm susceptibility to AmB by four- to eight-fold. In conclusion, A. fumigatus pre-exposure to VRZ concomitantly induces eDNA release and activates the stress response, which collectively confers AmB resistance in vitro
The Influence of Environmental Law on Nebraska Land Use
I. Introduction
II. Air Pollution … A. Federal Clean Air Act … B. The Nebraska Response … C. Significant Deterioration … D. Land Use Impacts
III. Water Pollution … A. Water Pollution Control Act Amendments of 1972 … B. Point Source Regulation … C. Erosion and Sedimentation … D. Dredge and Fill Materials
IV. Pesticides
V. Surface Mining
VI. Wildlife and Habitat … A. Federal Programs … B. State Program
- …