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The catalytic and electro-optical properties of TiO2-based materials depend on the defectivity of their electronic structures and in turn on the synthesis conditions. It is however less clear how t...

In order to cope with continuously increasing environmental demands, the maritime sector is investigating alternative solutions for the power generation on board. These solutions include both alternative fuel, such as Liquefied Natural Gas (LNG) and hydrogen, and green technologies, such as fuel cells (FC) and batteries. Although in-port emissions are responsible of a small percentage of the overall emissions, ports constitute sources of concentrated ship harmful emissions, potentially very dangerous for the human health. Moreover,the environmental regulations suggest switching present marine fuels as soon as possible. In this frame, this work investigates innovative solutions for the electric power generation in port for passenger ships in terms of cost and environmental benefits. These can be shore power solutions (such as cold ironing) and on-board solutions (such as dual fuel, fuel cell and others). The results show that some solutions could be more competitive than others according to specific operating conditions. The aim of the study is to identify the most eco-friendly and promising solutions. The cost analysis methodology takes into account the efficiency, fuel costs, operating and maintenance costs and the initial investment costs. The environmental comparison considers the emissions of nitrogen and sulphur oxides, carbon monoxide and dioxide, particulate matter and hydrocarbon.

Case Presentation A 19-year-old woman presented to pulmonary clinic with recurrent episodes of fevers and productive cough over the last 2 years. She was diagnosed with several episodes of respiratory infection that required antibiotic therapy. Her symptoms improved transiently after antibiotic therapy. However, symptoms continued to recur every 1 to 2 months. She denied any close TB contacts or travel outside the United States. She was a nonsmoker and had no history of immunodeficiency. There was no history of cystic fibrosis or any foreign body aspiration.

In this work, we demonstrate the superior exploration capabilities of the population-based methods over the sequential one-parameter parabolic interpolation (SOPPI) approach to optimise ReaxFF force field parameters. Evolutionary algorithms (EAs) are heuristic-based approaches using a population of concurrent models in the search space to evolve towards the global best through stochastic operations. The parallelisation of EAs scales almost linearly, and no differentiable objective function is required. These methods were tested for their search performance and convergence behaviour on different multi-dimensional, multimodal benchmark functions. The developed KVIK (Icelandic for: dynamic, in motion) optimisation framework features an extended training 1routine designed to parameterise solid-state systems efficiently. The optimisation routine was applied to train a reactive force field potential for metallic lithium and sodium and their interaction parameters. The KVIK-optimised ReaxFF potential function parameter set reproduces relative energy results from the density functional theory (DFT) reference data set within the standard deviation range established using the error estimation routine provided by the BEEF-vdW density functional. Finally, thermodynamically and kinetically driven surface growth phenomena on metallic Li- and Na-electrodes were investigated using coupled ReaxFF/Monte Carlo (MC) approaches.

High Power Microwave (HPM) sources are widely used as signal sources in radar, jammer, and Counter Improvised Explosive Devices (CIED). Such devices usually are heavy and bulky, characteristics that are in conflict with the small weight and power (SWaP) approach so that it is practically impossible to mount such HPMs on several platforms with reduced spaces (e.g., avionic, UAVs). During the last century, several devices have been proposed, all of them heavy due to the components that they need such as the magnetic material of the Magnetron, Klystron, or Gyrotron. Considering the HPM sources for pulsed applications, the VIRtual CAThode oscillatOR (Vircator) represents the best candidate due to the compact dimension and reduced weight due to the absence of a magnetic source. The signal generated by this HPM device is characterized by a pulsed output power of some GW for a narrow frequency below 10 GHz. In this work, the analysis of the three most used types of Vircator, Axial Vircator, Coaxial Vircator, and Reflex Triode, is reported. A novel anode design and characterization procedure is reported, which led to the analysis of the interaction between electrons and a realistic anode grid.

Primary Subject area Emergency Medicine - Paediatric Background While the management of febrile neutropenia in patients with cancer has clear, evidence-based guidelines, the management of previously healthy, immunocompetent children with a febrile illness and first episode of neutropenia is less understood. These patients are often similarly treated with empiric antibiotics and hospitalization despite studies demonstrating that this population, if they are well-appearing with a short history of neutropenia, is at low risk of serious bacterial infections. Therefore, less aggressive management should be considered in patients meeting low risk criteria. Objectives The aim of our quality improvement (QI) study was to decrease the number of unnecessary hospitalizations and empiric antibiotics prescribed by 50% over a 12-month period for otherwise healthy, well appearing patients presenting to the emergency department (ED) with a first episode of febrile neutropenia. Design/Methods A team of stakeholders from Hematology, Infectious Disease, Pediatrics and Emergency Medicine was assembled. A review of the literature, peer institutions and local practices of managing febrile neutropenia in healthy children was performed. Using the Model for Improvement, a guideline for the management of healthy children with first episode of febrile neutropenia was developed and refined using PDSA cycles. In January 2020, the guideline was launched for clinical use in the ED. Education, targeted audit and feedback, pathway modifications, and reminders were used to address knowledge gaps and staff turnover. A family of measures was analyzed using run charts and statistical process control (SPC) methods. Results Eighteen months of baseline data identified nineteen low risk patients with 84% either hospitalized and/or received antibiotics. It was also uncovered that many patients were misdiagnosed with neutropenia by excluding bands from the absolute neutrophil count (ANC). After the first twelve months of the intervention, sixteen patients met low risk criteria. Hospitalization and/or antibiotics use for this population decreased to 25% and all blood cultures were negative. Recognition of true severe febrile neutropenia also improved. Forty-one patients had a neutrophil count < 0.5, but an ANC > 0.5. Hospitalization and/or antibiotics use for this population decreased from 52% to 10%. Conclusion Through a multi-faceted, multidisciplinary QI study, we improved resource stewardship and value-based care by reducing unnecessary hospitalizations and antibiotics in low risk patients with a first episode of febrile neutropenia. Next steps include iterations to the guideline to increase impact along with sustainability planning. This work can easily be adopted by other pediatric and community sites caring for children.

This paper outlines a novel approach to design a waveguide to microstrip Finline transition, that allows a division by three of the RF power traveling inside a rectangular waveguide. The possibility of obtaining and odd power division of microwave and millimeter wave signals with such Finline transition is completely unexplored yet harbinger of great opportunities. Starting from a 3D CAD model of the structure and continuing with Electromagnetic simulations, the obtained results completely describe a transition able to achieve an almost perfect power splitting by three. Multyphisics simulations, show an intrinsic resistance to vibrations of such transition, allowing it to be installed on aircraft or satellites modules. Thanks to this achievement a total new kind of power devices will come next, exploiting this odd power division in fact, it will be possible to realize different types of microwave amplifiers, increasing the efficiency and decreasing the occupied size. At the Author’s best knowledge it is the first time a divider by three Finline transition is reported in literature.

This study aimed at investigating both the surface and bulk modifications occurring on fibrous erionite during leaching in a mimicked Gamble’s solution (MGS) at pH of 4.5 and T = 37 °C, up to one month of incubation. Samples were characterized by a multi-analytical approach: field-emission scanning electron microscopy (FE-SEM) was employed to investigate the morphological changes of both pristine and reacted fibres, inductively coupled plasma optical emission spectrometry (ICP-OES) was used to measure the concentration of the released cations, X-ray photoelectron spectroscopy (XPS) was exploited for highlighting possible modifications of surface chemistry, X-ray powder diffraction (XRPD) and high-resolution transmission electron microscopy (HR-TEM) were applied aiming to get information on the structural state of the fibres following the incubation. ICP results integrated with those obtained by both bulk- and surface-chemical characterization highlighted that erionite binds Na especially in the first 24 h of sample incubation in the MGS, following ion exchange with the extra framework cations, in particular Ca. Moreover, our new results show that the Na binding process caused structural modifications with the migration of Na toward the Ca2 site and redistribution of the cations within the erionite cage. TEM investigation pointed out that the interaction between erionite and MGS results in the formation of a new surface amorphous layer with an irregular lobate pattern on an earlier surface weathered layer. However, the silicate framework is not weakened by incubation in the MGS at acidic pH. In addition, on the basis of the Si release normalized to the mineral surface area, fibrous erionite resulted significantly more biodurable than amphibole asbestos. Notably, considering the primary role played by biodurability in inducing pathogenicity, this result certainly supports in vivo observations showing that erionite is much more tumorigenic than asbestos. Moreover, the ions released by erionite when immersed in MGS may trigger biological effects, such as those on lipid packing and membrane permeability. On this basis, we expect a regulatory definition that would provide protection from this carcinogenic fibre.

In this work, two acidic Nb P Si mixed oxide gel-derived materials characterized by Nb/P molar ratios equal to 2 (5Nb2.5P) and 1 (2.5NbP) were investigated for their surface and bulk properties in relation with the catalytic performances in the fructose dehydration reaction. The structural characteristics of the studied samples and the changes occurring after water treatment and after reaction were investigated by 29Si and 31P solid state nuclear magnetic resonance (MAS-NMR) and X-ray photoelectron (XPS) spectroscopies, while the characterization of their acidic properties was performed by base (2-phenylethylamine) adsorption in liquid phase. MAS-NMR showed that the phosphorus remains firmly anchored into the siloxane matrix after exposure to cold water for 5Nb2.5P sample and XPS confirmed the homogeneity of the sample composition. Both samples exhibited good intrinsic acidity and maintained significant effective acidity in polar-protic liquids; 2.5NbP manifested a double amount of acid sites compared to 5Nb2.5P, when 2-phenylethylamine is used as probe. Fructose dehydration to 5-(hydroxymethyl)furfural (HMF) on the two gel-derived catalysts was performed in water and in water-isopropanol solution under mild conditions (130 °C) working in a recirculation reaction line comprising a tubular catalytic reactor. In water-isopropanol solution, the samples displayed good performances, as expected thanks to the lively effective acidity. Around 45–50% fructose conversion was attained on both samples, with selectivity to HMF equal to about 50% on 2.5NbP gel-derived catalyst. Recycling tests showed satisfactorily stable activity during three consecutive runs.

The functional properties of metal oxide semiconductors depend on intrinsic and extrinsic defects. The population of intrinsic defects is strongly affected by the synthesis method and subsequent treatments of the material, while extrinsic defects can originate from suitable doping. Stoichiometric ZrO2 is a nonreducible oxide with a large band gap. Therefore, controlling and modulating its defect profile to induce energy states in the band gap is the sole possibility to make it a photocatalyst responsive to visible light. We report a method, based on low temperature sol−gel synthesis coupled with treatments performed in mild conditions, to obtain undoped visible light-responsive ZrO2−x. The electronic structure of these materials is interpreted in relation to their oxygen vacancy defect population. On the basis of a wide set of experimental measurements (X-ray photoelectron, steady-state and time-resolved photoluminescence, electron paramagnetic resonance, and UV−visible diffuse reflectance spectroscopy) and supported by density functional theory calculations, we demonstrate, for the first time, the predominance of positively charged F-center oxygen vacancies that do not give rise to Zr3+ species.

To describe the clinical features, upon initial presentation, of a cohort of patients with Vogt-Koyanagi-Harada (VKH) disease who live in Puerto Rico.A retrospective medical record review of patients with VKH was performed. The demographic and clinical characteristics were analyzed.Twenty-two patients who met the diagnostic criteria for VKH were identified and included in the analysis. The median age at presentation was 41 years; 68.2% were female, and all patients were Hispanics. Bilateral disease was present in 90.9% of patients, and 59.1% of patients were categorized as having probable VKH. A headache was reported in 54.5% of patients and was the most common complaint at the time of presentation; the second most common complaint was tinnitus, which was present in 22.7% of patients. Vitiligo, alopecia, and meningismus were each preset in 9.1% of patients while hearing loss and aseptic meningitis were each reported in 4.5% of patients. Seventy-seven percent of patients had either topical or systemic corticosteroid use prior to the initial encounter.Our study suggests that in Puerto Rico, patients with Vogt-Koyanagi-Harada disease may have a distinctive prevalence of characteristics at the presentation when compared to other ethnic groups, including other Hispanic cohorts.

This thesis looks at the political conditions of North Carolina from Post-Reconstruction, circa 1877, to 1905, in order to establish the rise of the Jim Crow era of the 20th century. By looking at the state political conditions and recognizing the position held by the federal government, I aim to answer how Jim Crow became legally established specifically in North Carolina. By analytically focusing on politics and combining that analysis with the actual number of laws being enacted, I argue that the year of 1900 was pivotal in legally establishing Jim Crow in North Carolina. I utilize On the Books: Jim Crow and Algorithms of Resistance, to identify peak years of Jim Crow laws enacted in the North Carolina State legislature, as well as track the political alliances and political campaign strategies of the Democratic and Republican parties. I argue that the foundation of the Jim Crow era was legally established in the South through the planter and merchant classes dominating in response to a strong a bi-racial coalition of workers and farmers in the 1890s, known as the Fusion movement. By looking at a wide range of years, I track the changes in the political conditions that led to the legal cementation of Jim Crow. From 1900 forward, there would be a more effective and predictable regime that would sweep the South for decades to come.

The fight for school desegregation in North Carolina was a hard fought and long battle. Despite 1954���55 Brown v. Board of Education decisions of the US Supreme Court, school desegregation persisted. The significance of the first and second Brown decisions (often referred to as Brown I and Brown II) was not overlooked but challenged because of how the Brown decision underestimated how to fully eliminate barriers that manifested through unequal treatment and funding of segregated schools. North Carolina politicians employed mechanisms such as freedom of choice plans, the Pupil Assignment Act, and the Pearsall Plan to ensure the slow integration of North Carolina public schools. The evaluation of public opinion, North Carolina politics, and legal decisions employs a robust image of the battle between those who wanted integration and those who were staunch proponents of segregated schooling. This article provides an understanding of North Carolina���s ���moderate��� reputation and evaluates the compliance of North Carolina government officials to national legislation such as the Civil Rights Act of 1964 and federal financial assistance measures through the 1965 Elementary and Secondary Education Act. By analyzing national government legislation put forth in congruence with the fourth circuit district court case Coppedge v. Franklin County Board of Education [1967] and the Supreme Court case Swann v. Charlotte-Mecklenburg Board of Education [1971], this article shows the contributions of two legal cases to the desegregation of North Carolina public schools

This paper deals with the problem of the optimal rating of mineral-oil-immersed transformers in large wind farms. The optimal rating is derived based on the probabilistic analyses of wind power generation through the Ornstein–Uhlenbeck stochastic process and on thermal model of the transformer through the integration of stochastic differential equations. These analyses allow the stochastic characterization of lifetime reduction of the transformer and then its optimal rating through a simple closed form. The numerical application highlights the effectiveness and easy applicability of the proposed methodology. The proposed methodology allows deriving the rating of transformers which better fits the specific peculiarities of wind power generation. Compared to the conventional approaches, the proposed method can better adapt the transformer size to the intermittence and variability of the power generated by wind farms, thus overcoming the often-recognized reduced lifetime.