The digital surgeon\u27s warning: Do disclaimers have a place in beauty and fashion advertising?

The purpose of this study is to investigate the effects of disclaimers of photogenic manipulation, models’ body types, and the interaction between the two through the theoretical lenses of social comparison theory and priming effects. In an online experiment, this study employs a 3 (no disclaimer, presence of digital enhancement disclaimer, absence of digital enhancement disclaimer) by 2 (thin model body type and average model body type) factorial analysis to tease apart the effects of disclaimers on consumers (social comparison, self-esteem, and wishful identification) and the organizations that are compelled or choose to employ them (brand attitudes and perceptions of credibility, perceived organizational morality, purchasing intention, and loyalty). The results of this study highlight the implications and considerations for advertisements in the beauty and fashion industries as well as any company that uses digital manipulation on physically attractive models in their advertisements

Catalysts for Portable, Solid State Hydrogen Genration Systems

Hydrogen and air powered proton exchange membrane fuel cells are a potential alternative to batteries. In portable power systems, the design requirements often focus on cost efficiency, energy density, storability, as well as safety. Ammonia borane (AB), a chemical hydride containing 19.6 wt. % hydrogen, has a high hydrogen capacity and is a stable and non-toxic candidate for storing hydrogen in portable systems. Throughout this work, Department of Energy guidelines for low power portable hydrogen power systems were used as a baseline and comparison with commercially available systems. In order to make this comparison, the system parameters of a system using AB hydrolysis were estimated by developing capacity and cost correlations from the commercial systems and applying them to this work. Supporting experiments were designed to evaluate a system that would use a premixed solid storage bed of AB and a catalyst. This configuration would only require a user input of water in order to initiate the hydrogen production. Using ammonia borane hydrolysis, the hydrogen yield is ∼9 wt. %, when all reactants are considered. In addition to the simplicity of initiating the reaction, hydrolysis of AB has the advantage of suppressing the production of some toxic borazines that are present when AB is thermally decomposed. However, ammonia gas will be formed and this problem must be addressed, as ammonia is damaging to PEM fuel cells. The catalyst focused on throughout this work was Amberlyst - 15; an ion exchange resin with an acid capacity of 4.7 eq/kg and ammonia adsorbent. At less than $0.30/g, this is a cost effective alternative to precious metal catalysts. The testing with this catalyst was compared to a traditional catalyst in literature, 20$40/g. The Amberlyst catalyst was found to reduce the formation of ammonia in the gas products from ∼3.71 wt. % with the Pt/C catalyst to90 % to \u3c 30 % over a 70 day aging study. This results implies the need for a systems scale solution, such as mechanical separation, or a material scale solution, such as coating the Amberlyst or AB in a water soluble coating. It was found that ammonia borane catalyzed hydrolysis, using Amberlyst - 15 as a catalyst, has potential to be a cost effective, energy dense, and safe option for generating hydrogen for a portable fuel cell system

AUTOMATIC POST-ADOPTIVE INFORMATION TECHNOLOGY USE: THE ROLE OF INNOVATIVENESS GOAL

The business value of information technology (IT) is realized through the continuous use of IT subsequent to users’ adoption. Understanding post-adoptive IT usage is useful in realizing potential IT business value. Most previous research on post-adoptive IT usage, however, dismisses the unintentional and unconscious aspects of usage behavior. This paper advances understanding of the unintentional, unconscious, and thereby automatic usage of IT features during the post-adoptive stage. Drawing from Social Psychology literature, we argue human behaviors can be triggered by environmental cues and directed by the person’s mental goals, thereby operating without a person’s consciousness and intentional will. On this basis, we theorize the role of a user’s innovativeness goal, as the desired state of an act to innovate, in directing the user’s unintentional, unconscious, and automatic post-adoptive IT feature usage behavior. To test the hypothesized mechanisms, a human experiment employing a priming technique, is described

Optimization under uncertainty and risk: Quadratic and copositive approaches

Robust optimization and stochastic optimization are the two main paradigms for dealing with the uncertainty inherent in almost all real-world optimization problems. The core principle of robust optimization is the introduction of parameterized families of constraints. Sometimes, these complicated semi-infinite constraints can be reduced to finitely many convex constraints, so that the resulting optimization problem can be solved using standard procedures. Hence flexibility of robust optimization is limited by certain convexity requirements on various objects. However, a recent strain of literature has sought to expand applicability of robust optimization by lifting variables to a properly chosen matrix space. Doing so allows to handle situations where convexity requirements are not met immediately, but rather intermediately. In the domain of (possibly nonconvex) quadratic optimization, the principles of copositive optimization act as a bridge leading to recovery of the desired convex structures. Copositive optimization has established itself as a powerful paradigm for tackling a wide range of quadratically constrained quadratic optimization problems, reformulating them into linear convex-conic optimization problems involving only linear constraints and objective, plus constraints forcing membership to some matrix cones, which can be thought of as generalizations of the positive-semidefinite matrix cone. These reformulations enable application of powerful optimization techniques, most notably convex duality, to problems which, in their original form, are highly nonconvex. In this text we want to offer readers an introduction and tutorial on these principles of copositive optimization, and to provide a review and outlook of the literature that applies these to optimization problems involving uncertainty

Accuracy Analysis of the Measurement of Centre of Gravity and Moment of Inertia with a Swing

Floating devices under wave and current loads are typically designed based on numerical methods followed by a validation with experimental investigations. This allows an independent check due to the comparison of two different modelling approaches based on different assumptions. At an early stage of the project, numerical simulations are based on theoretical (ideal) values of the centre of gravity (CG) and moment of inertia (MI). The building process of a scaled model results very often in a requested simplification of certain parts, which can influence the CG and also the MI of the scaled model. Knowing those discrepancies allows us to improve the comparability of both approaches but the measurement of those values is connected with either a higher uncertainty or a high level of effort. A significant improvement of such measurements can be reached by the deployment of a specific experimental set-up. This paper presents the classification of the newly designed swing with a high accuracy inertial inclinometer, which was verified by the marker-based motion capturing system. The achieved experiences are useful for the future use of the set-up as well as similar investigations. The comparison with the theoretical values for the swing as well as an example model showed very good agreements and a high accuracy of few millimetres for the CG and an error smaller 1% for MI

Large-scale investigation into iceberg-tsunamis generated by various iceberg calving mechanisms

© 2020 Elsevier B.V. Mass balance analysis of ice sheets is a key component to understand the effects of global warming with iceberg calving as a significant contributor. Calving recently generated tsunamis of up to 50 m in amplitude endangering human beings and coastal infrastructure. Such iceberg-tsunamis (IBTs) have been investigated based on 66 unique large-scale experiments conducted in a 50 m × 50 m large basin at constant water depth h. The experiments involved five iceberg calving mechanisms: A: capsizing, B: gravity-dominated fall, C: buoyancy-dominated fall, D: gravity-dominated overturning and E: buoyancy-dominated overturning. The kinematics of the up to 187 kg heavy plastic blocks mimicking icebergs was measured with a motion sensor and the wave profiles were recorded with wave probes at up to 35 locations. The IBTs from the gravity-dominated mechanisms (B and D) are roughly an order of magnitude larger than from mechanisms A, C and E. Empirical equations for preliminary hazard assessment and mitigation for the maximum wave height, amplitude and period for both the near- and far-field are derived for the five calving mechanisms individually and combined. The relative released energy, Froude number and relative iceberg width are the most influential dimensionless parameters in these equations. A maximum wave height decay trend close to (r/h)−1.0 is observed, with r as the radial distance, in agreement with the theoretical wave decay from a point source. The empirical equations are applied to a past event resulting in a good agreement and the upscaled wave periods to typical Greenlandic conditions overlap with the lower spectrum of landslide-tsunamis. However, empirical equations for landslide-tsunamis were found to be of limited use to predict IBTs in the far-field supporting the need of the newly introduced empirical equations for IBT hazard assessment and mitigation

Analyse des Einflusses von unterschiedlichen Narkoseverfahren auf die intraoperative Hämodynamik und den Katecholaminbedarf bei Lebertransplantation

Zielsetzung Sowohl Narkosen mit Narkosegasen, als auch total intravenöse Anästhesie sind gängige und etablierte Verfahren in der Anästhesie. Im Gegensatz zu Aspekten wie Awareness und postoperative Aufwachzeiten, ist die intraoperative Hämodynamik und der intraoperative Katecholaminbedarf bisher wenig untersucht worden. Unser Ziel war es zu zeigen, dass das Narkoseverfahren einen Einfluss auf die intraoperative Hämodynamik und den intraoperativen Katecholaminbedarf haben kann. Methodik: In Rahmen einer retrospektiven Untersuchung wurden die digital erfassten Narkoseprotokolle, sowie die Patientenakten und Kurven der Intensivstation von 261 Patienten, bei denen im Zeitraum von Juni 2006 bis Dezember 2011 eine Lebertransplantation durchgeführt wurde, ausgewertet. Die Narkose wurde entweder als total-intravenöse Anästhesie (TIVA) oder balancierte Anästhesie (BA) mit Sevofluran durchgeführt. Hierbei wurden der präoperative Status, der perioperative Verlauf (einschließlich der erweiterten hämodynamischen Parameter (systolischer Blutdruck (RRsyst), arterieller Mitteldruck MAP), Zentralvenöser Druck (ZVD), Herzindex (CI), Schlagvolumenvarianz (SVV) und pulmonalarterieller Druck (PAP) und aller gegebenen Medikamente), sowie der postoperative Status erfasst und ausgewertet. Die Kreislaufparameter und Medikamentendosierungen wurden zu den Zeitpunkten 60 (= 60minPrä) und 15 (= 15minPrä) Minuten vor und 15 (= 15minPost) und 60 Minuten (= 60minPost) nach Reperfusion erfasst, ebenso wie die minimalen, maximalen und durchschnittlichen Werte bzw. Dosierungen. Ergebnis Es wurden 262 Patienten eingeschlossen, die entweder mit TIVA (n = 85) oder BA (n = 177) narkotisiert wurden. Die Patientendemographie unterschied sich nicht zwischen den beiden untersuchten Gruppen. Die TIVA-Gruppe wies an allen untersuchten Zeitpunkten, ebenso wie im Durchschnitt (p = <0,0001) signifikant höhere MAP-Werte auf (p = <0,0001 60minPrä & 60minPost, p = 0,024 15minPrä, p = 0,012 15minPost). Gleichzeitig waren der Noradrenalin-Bedarf an allen untersuchten Zeitpunkten (p = <0,0001 alle 4 Zeitpunkte) signifikant niedriger, genau wie der Adrenalin- (p = <0,0001 bzw. p = 0,038 15 bzw. 60minPost) und Vasopressin-Bedarf (p = 0,003 bzw. p = <0,0001 60minPost) an beiden Zeitpunkten nach der Reperfusion. Das Gesamtüberleben in den ersten 36 Monaten war in der TIVA-Gruppe höher, die Intensivaufenthaltsdauer (TIVA 11,9 ±13,2 vs. BA 12,2 ±15,1) und die postoperative Beatmungsdauer (77,3 h (TIVA) vs. 104,8 h (BA)) kürzer. Die Unterschiede waren hierbei statistisch nicht signifikant. Schlussfolgerung Die Ergebnisse legen nahe, dass eine Propofol-basierte TIVA mit einer stabileren Hämodynamik bei niedrigerem Katecholaminbedarf im gesamten perioperativen Verlauf von Lebertransplantationen einhergeht. Um valide Aussagen über das Outcome treffen zu können, erscheint die Durchführung einer randomisierten, kontrollierten Studie sinnvoll