Generating Generalized Distributions from Dynamical Simulation

We present a general molecular-dynamics simulation scheme, based on the Nose' thermostat, for sampling according to arbitrary phase space distributions. We formulate numerical methods based on both Nose'-Hoover and Nose'-Poincare' thermostats for two specific classes of distributions; namely, those that are functions of the system Hamiltonian and those for which position and momentum are statistically independent. As an example, we propose a generalized variable temperature distribution that designed to accelerate sampling in molecular systems.Comment: 10 pages, 3 figure

Post-Flight Analysis of the Guidance, Navigation, and Control Performance During Orion Exploration Flight Test 1

The first test flight of the Orion Multi-Purpose Crew Vehicle presented additional challenges for guidance, navigation and control as compared to a typical re-entry from the International Space Station or other Low Earth Orbit. An elevated re-entry velocity and steeper flight path angle were chosen to achieve aero-thermal flight test objectives. New IMU's, a GPS receiver, and baro altimeters were flight qualified to provide the redundant navigation needed for human space flight. The guidance and control systems must manage the vehicle lift vector in order to deliver the vehicle to a precision, coastal, water landing, while operating within aerodynamic load, reaction control system, and propellant constraints. Extensive pre-flight six degree-of-freedom analysis was performed that showed mission success for the nominal mission as well as in the presence of sensor and effector failures. Post-flight reconstruction analysis of the test flight is presented in this paper to show whether that all performance metrics were met and establish how well the pre-flight analysis predicted the in-flight performance

Swiss Marketing Leadership Studie 2018 : Geschwindigkeit vs. Beständigkeit

Der technologische Fortschritt sowie die Digitalisierung der Gesellschaft, aber auch der Unternehmen, sind ausschlaggebend für schnelle Innovationen und immer kürzer werdende Produkt- und Dienstleistungslebenszyklen (Wallmüller, 2017). Infolgedessen verändern sich auch die Bedürfnisse und das Verhalten der Kunden. Die sich stetig verändernden Umweltbedingungen stellen Unternehmen vor die Herausforderung, diese zunehmende Dynamik und Komplexität zu bewältigen (Schoeneberg, 2014). So bleibt auch das Marketing von dieser Herausforderung nicht unberührt. Da die verändernden Kundenanforderungen rechtzeitig erkannt und entsprechend passgenaue Massnahmen getroffen werden müssen, kommt ihr als Schnittstelle zum Markt eine immer bedeutsamere Rolle im Unternehmen zu. Um eine langfristige Wettbewerbsfähigkeit von Unternehmen gewährleisten zu können, sind rasche Reaktionszeiten sowie flexible Anpassungsmöglichkeiten zu zentralen Voraussetzungen geworden (Smart, 2016). Unter diesem Aspekt gewinnt die Geschwindigkeit bzw. die Agilität im Marketing für ein Unternehmen zunehmend an Bedeutung. Dies bestätigt ebenfalls eine aktuelle Studie von Fryrear (2018), in welcher über die steigende Bedeutung von Agilität im Kontext des Marketings diskutiert wird. Die Resultate zeigen, dass rund 37 Prozent der befragten Marketingteams bereits agile Prozesse anwenden, während sich rund 61 Prozent derzeit damit befassen, in naher Zukunft (innerhalb der nächsten 12 Monate) agiler zu werden. Agilität stellt somit nicht nur einen vorübergehenden Trend dar, sondern eine ernstzunehmende Thematik, welche im Marketing künftig eine immer zentralere Rolle einnehmen wird. Doch wird im Marketing überall mehr Geschwindigkeit benötigt oder gibt es Bereiche, in denen eher auf Beständigkeit und Kontinuität gesetzt werden sollte? Ist es ein «entweder oder» oder ein «sowohl als auch»? Mit diesen und weiteren Fragen beschäftigt sich auch das Institut für Marketing Management der ZHAW in seiner Forschung seit einiger Zeit

Ceramide Metabolism Regulates A Neuronal Nadph Oxidase Influencing Neuron Survival During Inflammation

Thesis (Ph.D.) University of Alaska Fairbanks, 2009Inflammation is a major component of acute and chronic pathologies of the central nervous system, including psychiatric disorders. Microglia respond to pathogens, injury, and toxins by secreting inflammatory mediators including pro-inflammatory cytokines in an event known as neuroinflammation. This thesis research investigated a link between neuroinflammation and oxidative stress, and ultimately neurodegeneration. The cytokine tumor necrosis factor alpha was shown to stimulate a neuronal NADPH oxidase (NOX), specifically by stimulating the production of ceramide and ceramide-1-phosphate via Mg 2+-neutral sphingomyelinase (Mg2+-nSMase) and ceramide kinase. Intriguingly, glucosylceramide blocked NOX activation, linking ceramide neutralization directly to a decline in oxidative stress. Most importantly, NOX activity interfered with actin and sphingosine kinase-1 via oxidation, demonstrating a positive and detrimental feedback mechanism that impedes neuronal survival pathways. Interestingly, crude extracts from wild Alaskan bog blueberries showed the ability to interfere with Mg2+-nSMase, demonstrating a specific neuroprotective property of the berry. Altogether, this thesis research defined a key neuronal pathway linking inflammation to oxidative stress via ceramide metabolism, potentially allowing for future therapeutic development to improve neuronal function and survival

Spectral discrimination of breast pathologies in situ using spatial frequency domain imaging

Introduction: Nationally, 25% to 50% of patients undergoing lumpectomy for local management of breast cancer require a secondary excision because of the persistence of residual tumor. Intraoperative assessment of specimen margins by frozen-section analysis is not widely adopted in breast-conserving surgery. Here, a new approach to wide-field optical imaging of breast pathology in situ was tested to determine whether the system could accurately discriminate cancer from benign tissues before routine pathological processing. Methods: Spatial frequency domain imaging (SFDI) was used to quantify near-infrared (NIR) optical parameters at the surface of 47 lumpectomy tissue specimens. Spatial frequency and wavelength-dependent reflectance spectra were parameterized with matched simulations of light transport. Spectral images were co-registered to histopathology in adjacent, stained sections of the tissue, cut in the geometry imaged in situ. A supervised classifier and feature-selection algorithm were implemented to automate discrimination of breast pathologies and to rank the contribution of each parameter to a diagnosis. Results: Spectral parameters distinguished all pathology subtypes with 82% accuracy and benign (fibrocystic disease, fibroadenoma) from malignant (DCIS, invasive cancer, and partially treated invasive cancer after neoadjuvant chemotherapy) pathologies with 88% accuracy, high specificity (93%), and reasonable sensitivity (79%). Although spectral absorption and scattering features were essential components of the discriminant classifier, scattering exhibited lower variance and contributed most to tissue-type separation. The scattering slope was sensitive to stromal and epithelial distributions measured with quantitative immunohistochemistry. Conclusions: SFDI is a new quantitative imaging technique that renders a specific tissue-type diagnosis. Its combination of planar sampling and frequency-dependent depth sensing is clinically pragmatic and appropriate for breast surgical-margin assessment. This study is the first to apply SFDI to pathology discrimination in surgical breast tissues. It represents an important step toward imaging surgical specimens immediately ex vivo to reduce the high rate of secondary excisions associated with breast lumpectomy procedures

The Type Ic Supernova 1994I in M51: Detection of Helium and Spectral Evolution

We present a series of spectra of SN 1994I in M51, starting 1 week prior to maximum brightness. The nebular phase began about 2 months after the explosion; together with the rapid decline of the optical light, this suggests that the ejected mass was small. Although lines of He I in the optical region are weak or absent, consistent with the Type Ic classification, we detect strong He I λ10830 absorption during the first month past maximum. Thus, if SN 1994I is a typical Type Ic supernova, the atmospheres of these objects cannot be completely devoid of helium. The emission-line widths are smaller than predicted by the model of Nomoto and coworkers, in which the iron core of a low-mass carbon-oxygen star collapses. They are, however, larger than in Type Ib supernovae

Features of informatization of education in Poland and Ukraine

У тезах описуються пріоритети політики ЄС у сфері інформатизації освіти в контексті реалізації програми «Освіта та професійна підготовка 2020» за прикладом Польщі. Розглядаються стратегічні європейські документи щодо інформатизації освіти, розвитку цифрових компетентностей і переходу до відкритої освіти. Окреслено інфраструктуру розвитку дистанційної освіти у Республіці Польща.The theses describe the priorities of EU policy in the field of informatization of education in the context of the implementation of the program "Education and Training 2020", for example in Poland. The strategic European documents concerning informatization of education, development of digital competences and transition to open education are considered. The infrastructure of development of distance education in the Republic of Poland is outlined

Electron Interactions in Carbon Nanomaterials

The following research reflects two areas of interest in carbon nanomaterials: (1) enzymatic oxidation and (2) photocatalytic applications. Horseradish peroxidase (HRP) is known to catalyze oxidation of carbon nanomaterials. Here, we closely examine the kinetics of enzymatic oxidation of carbon nanotubes (CNTs) using HRP. We show that CNTs oxidized by harsh acid treatment become shorter, more defective, and lose their specific absorption bands and fluorescent signals. After treatment with HRP and H2O2, these oxidized CNTs show a decrease in average CNT length, a decrease in defective area, and return of characteristic absorption bands and fluorescence. We observed that CNTs chemically oxidized using weaker oxidation treatment were shortened, slightly more defective than before acid treatment, did not lose their characteristic absorption bands, but did lose fluorescence. After treatment with HRP and H2O2 there was a decrease in length, a decrease in defective area, no observed change in absorption spectra bands and fluorescent signal did not return. H2O2 treated oxidized CNTs, showed similar results to HRP treated samples but did not recover their fluorescent signals. TiO2 is a popular photocatalyst due to its small band gap, low cost, and low toxicity. Limitations in photocatalysis using TiO2 are due to electron – hole recombination following electron excitation from the valence band to conduction band. Efforts to retard electron – hole recombination involve doping TiO2 with metals, which have electron trapping sites on their surfaces. Carbon nanomaterials show promise as TiO2 dopants due to their large surface area,electron storage capacity, and interaction with metal oxide surface groups. Here, we demonstrate synthesis of TiO2 – carbon nanomaterials using sol – gel techniques and that electron transfer is possible under UV irradiation. Comparing synthesized TiO2-SWNTs and commercially available anatase TiO2 nanoparticles, we find no significant improvement in photocatalytic oxidation of dye. Furthermore, TiO2 – SWNTs do not photoreduce CO2. P25 TiO2 nanoparticles oxidize dye in these studies, and have demonstrated the ability to reduce CO2 in published works. Lack of homogeneity in the TiO2 crystalline structure may be responsible for these differences. We show prolonged UV expose may degrade TiO2 – GO photocatalysts, possibly through ROS generation