Light splitting in nanoporous gold and silver

Figure Persented: Nanoporous gold and silver exhibit strong, omnidirectional broad-band absorption in the far-field. Even though they consist entirely of gold or silver atoms, these materials appear black and dull, in great contrast with the familiar luster of continuous gold and silver. The nature of these anomalous optical characteristics is revealed here by combining nanoscale electron energy loss spectroscopy with discrete dipole and boundary element simulations. It is established that the strong broad-band absorption finds its origin in nanoscale splitting of light, with great local variations in the absorbed color. This nanoscale polychromaticity results from the excitation of localized surface plasmon resonances, which are imaged and analyzed here with deep sub-wavelength, nanometer spatial resolution. We demonstrate that, with this insight, it is possible to customize the absorbance and reflectance wavelength bands of thin nanoporous films by only tuning their morphology. © 2011 American Chemical Society

Differential calculus with imprecise input and its logical framework

We develop a domain-theoretic Differential Calculus for locally Lipschitz functions on finite dimensional real spaces with imprecise input/output. The inputs to these functions are hyper-rectangles and the outputs are compact real intervals. This extends the domain of application of Interval Analysis and exact arithmetic to the derivative. A new notion of a tie for these functions is introduced, which in one dimension represents a modification of the notion previously used in the one-dimensional framework. A Scott continuous sub-differential for these functions is then constructed, which satisfies a weaker form of calculus compared to that of the Clarke sub-gradient. We then adopt a Program Logic viewpoint using the equivalence of the category of stably locally compact spaces with that of semi-strong proximity lattices. We show that given a localic approximable mapping representing a locally Lipschitz map with imprecise input/output, a localic approximable mapping for its sub-differential can be constructed, which provides a logical formulation of the sub-differential operator

Quantum Gates and Memory using Microwave Dressed States

Trapped atomic ions have been successfully used for demonstrating basic elements of universal quantum information processing (QIP). Nevertheless, scaling up of these methods and techniques to achieve large scale universal QIP, or more specialized quantum simulations remains challenging. The use of easily controllable and stable microwave sources instead of complex laser systems on the other hand promises to remove obstacles to scalability. Important remaining drawbacks in this approach are the use of magnetic field sensitive states, which shorten coherence times considerably, and the requirement to create large stable magnetic field gradients. Here, we present theoretically a novel approach based on dressing magnetic field sensitive states with microwave fields which addresses both issues and permits fast quantum logic. We experimentally demonstrate basic building blocks of this scheme to show that these dressed states are long-lived and coherence times are increased by more than two orders of magnitude compared to bare magnetic field sensitive states. This changes decisively the prospect of microwave-driven ion trap QIP and offers a new route to extend coherence times for all systems that suffer from magnetic noise such as neutral atoms, NV-centres, quantum dots, or circuit-QED systems.Comment: 9 pages, 4 figure

Prediction of length of stay for stroke patients using artificial neural networks

Strokes are neurological events that affect a certain area of the brain. Since brain controls fundamental body activities, brain cell deterioration and dead can lead to serious disabilities and poor life quality. This makes strokes the leading cause of disabilities and mortality worldwide. Patients that suffer strokes are hospitalized in order to be submitted to surgery and receive recovery therapies. Thus, it’s important to predict the length of stay for these patients, since it can be costly to them and their family, as well as to the medical institutions. The aim of this study is to make a prediction on the number of days of patients’ hospital stays based on information available about the neurological event that happened, the patient’s health status and surgery details. A neural network was put to test with three attribute subsets with different sizes. The best result was obtained with the subset with fewer features obtaining a RMSE and a MAE of 5.9451 and 4.6354, respectively.FCT - Fundação para a Ciência e a Tecnologia (UID/CEC/00319/2019

Effect of sedation with detomidine and butorphanol on pulmonary gas exchange in the horse

<p>Abstract</p> <p>Background</p> <p>Sedation with α₂-agonists in the horse is reported to be accompanied by impairment of arterial oxygenation. The present study was undertaken to investigate pulmonary gas exchange using the Multiple Inert Gas Elimination Technique (MIGET), during sedation with the α₂-agonist detomidine alone and in combination with the opioid butorphanol.</p> <p>Methods</p> <p>Seven Standardbred trotter horses aged 3–7 years and weighing 380–520 kg, were studied. The protocol consisted of three consecutive measurements; in the unsedated horse, after intravenous administration of detomidine (0.02 mg/kg) and after subsequent butorphanol administration (0.025 mg/kg). Pulmonary function and haemodynamic effects were investigated. The distribution of ventilation-perfusion ratios (V_A/Q) was estimated with MIGET.</p> <p>Results</p> <p>During detomidine sedation, arterial oxygen tension (PaO₂) decreased (12.8 ± 0.7 to 10.8 ± 1.2 kPa) and arterial carbon dioxide tension (PaCO₂) increased (5.9 ± 0.3 to 6.1 ± 0.2 kPa) compared to measurements in the unsedated horse. Mismatch between ventilation and perfusion in the lungs was evident, but no increase in intrapulmonary shunt could be detected. Respiratory rate and minute ventilation did not change. Heart rate and cardiac output decreased, while pulmonary and systemic blood pressure and vascular resistance increased. Addition of butorphanol resulted in a significant decrease in ventilation and increase in PaCO₂. Alveolar-arterial oxygen content difference P(A-a)O₂remained impaired after butorphanol administration, the V_A/Q distribution improved as the decreased ventilation and persistent low blood flow was well matched. Also after subsequent butorphanol no increase in intrapulmonary shunt was evident.</p> <p>Conclusion</p> <p>The results of the present study suggest that both pulmonary and cardiovascular factors contribute to the impaired pulmonary gas exchange during detomidine and butorphanol sedation in the horse.</p

Plugging a hole and lightening the burden: A process evaluation of a practice education team

Aim: To investigate the perceptions of clinical and senior managers about the role of Practice Educators employed in one acute hospital in the UK. Background: Producing nurses who are fit for practice, purpose and academic award is a key issue for nurse education partnership providers in the UK. Various new models for practice learning support structures and new roles within health care institutions have been established. To sustain funding and policy support for these models, there is a need for evaluation research. Design: A process evaluation methodology was employed to determine the current value of a practice education team and to provide information to guide future direction. Methods: Data were collected through semi-structured telephone interviews using a previously designed schedule. All senior nurse managers (N=5) and a purposive sample of clinical managers (n=13) who had personal experience of and perceptions about the role of practice educators provided the data. Interview notes were transcribed, coded and a thematic framework devised to present the results. Results: A number of key themes emerged including: qualities needed for being a successful practice educator; visibility and presence of practice educators; providing a link with the university; ‘plugging a hole’ in supporting learning needs; providing relief to practitioners in dealing with ‘the burden of students’; alleviating the ‘plight of students’; and effects on student attrition. Conclusions: Findings provided evidence for the continued funding of the practice educator role with improvements to be made in dealing with stakeholder expectations and outcomes. Relevance to clinical practice: In the UK, there still remain concerns about the fitness for practice of newly registered nurses, prompting a recent national consultation by the professional regulating body. Despite fiscal pressures, recommendations for further strengthening of all systems that will support the quality of practice learning may continue to sustain practice learning support roles

Interprofessional communication with hospitalist and consultant physicians in general internal medicine : a qualitative study

This study helps to improve our understanding of the collaborative environment in GIM, comparing the communication styles and strategies of hospitalist and consultant physicians, as well as the experiences of providers working with them. The implications of this research are globally important for understanding how to create opportunities for physicians and their colleagues to meaningfully and consistently participate in interprofessional communication which has been shown to improve patient, provider, and organizational outcomes

LsrR-Mediated Quorum Sensing Controls Invasiveness of Salmonella typhimurium by Regulating SPI-1 and Flagella Genes

Bacterial cell-to-cell communication, termed quorum sensing (QS), controls bacterial behavior by using various signal molecules. Despite the fact that the LuxS/autoinducer-2 (AI-2) QS system is necessary for normal expression of Salmonella pathogenicity island-1 (SPI-1), the mechanism remains unknown. Here, we report that the LsrR protein, a transcriptional regulator known to be involved in LuxS/AI-2-mediated QS, is also associated with the regulation of SPI-1-mediated Salmonella virulence. We determined that LsrR negatively controls SPI-1 and flagella gene expressions. As phosphorylated AI-2 binds to and inactivates LsrR, LsrR remains active and decreases expression of SPI-1 and flagella genes in the luxS mutant. The reduced expression of those genes resulted in impaired invasion of Salmonella into epithelial cells. Expression of SPI-1 and flagella genes was also reduced by overexpression of the LsrR regulator from a plasmid, but was relieved by exogenous AI-2, which binds to and inactivates LsrR. These results imply that LsrR plays an important role in selecting infectious niche of Salmonella in QS dependent mode

The socioeconomic burden of SLE.

Systemic lupus erythematosus (SLE) is a chronic, relapsing-remitting, multisystemic autoimmune inflammatory disorder that predominantly affects women of childbearing age. Much has been written about the clinical course and long-term damage associated with SLE, as well as the reduced life expectancy of patients with this condition. In addition, studies have emphasized the socioeconomic and psychosocial impact of SLE, although the monetary cost of caring for patients with the disorder has only been evaluated in a modest number of studies and a restricted number of countries. SLE has a negative impact on quality of life and is associated with high health-care costs and significant productivity loss. Factors associated with increased cost of SLE include long disease duration, high disease activity and damage, poor physical and mental health, and high education and employment levels. Similarly, high disease activity and damage, poor physical health, certain disease manifestations, as well as poor family and social support are associated with poor health-related quality of life outcomes. SLE incurs a great burden on both the patient and society. Long-term prospective studies should be encouraged to monitor the costs and psychosocial impact of this condition, and to better understand the factors that are associated with poor outcomes.postprin