Synthesis of large-pore zeolites from chiral structure-directing agents with two l-prolinol units

In this work, we perform an in-depth experimental and computational study about the structure-directing effect of two new chiral organic quaternary ammonium dications bearing two N-methyl-prolinol units linked by a xylene spacer in para or meta relative orientation, displaying four enantiopure stereogenic centers in (S) configuration. Synthesis results show that the para-xylene derivative is an efficient structure-directing agent, promoting the crystallization of ZSM-12 (in pure-silica composition), beta zeolite (as pure-silica, or in the presence of Al or Ge), and a mixture of polymorphs C, A and B of zeolite beta (in the presence of Ge). In contrast, the meta-xylene derivative showed a much poorer structure-directing activity, yielding only amorphous materials unless Ge is present in the gel, where beta and polymorph C (together with A and B) zeolites crystallized. Molecular simulations showed that the para-xylene dication displays a cylindrical shape suitable for confining in zeolite pores, while the meta-xylene derivative has an angular shape that shifts from the typical dimensions required for 12MR zeolite channels. Despite enantio-purity of the para-xylene dication with (S, S, S, S) configuration, no enrichment in polymorph A of the zeolite beta samples obtained was observed by Transmission Electron Microscopy. With the aid of molecular simulations, the failure in transferring chirality to the zeolite is explained by the loose fit of this SDA in the large-pores of zeolite beta, and a lack of close geometrical fit with the chiral element of polymorph A, as evidenced by the very similar interaction of the cation with the two enantiomorphic space groups of polymorph A. Nevertheless, the molecular-level knowledge gained in this work can provide insights for the future design of more efficient SDAs towards the synthesis of chiral zeolites

Multiscale entropy analysis of unattended oximetric recordings to assist in the screening of paediatric sleep apnoea at home

Producción CientíficaUntreated paediatric obstructive sleep apnoea syndrome (OSAS) can severely affect the development and quality of life of children. In-hospital polysomnography (PSG) is the gold standard for a definitive diagnosis though it is relatively unavailable and particularly intrusive. Nocturnal portable oximetry has emerged as a reliable technique for OSAS screening. Nevertheless, additional evidences are demanded. Our study is aimed at assessing the usefulness of multiscale entropy (MSE) to characterise oximetric recordings. We hypothesise that MSE could provide relevant information of blood oxygen saturation (SpO2) dynamics in the detection of childhood OSAS. In order to achieve this goal, a dataset composed of unattended SpO2 recordings from 50 children showing clinical suspicion of OSAS was analysed. SpO2 was parameterised by means of MSE and conventional oximetric indices. An optimum feature subset composed of five MSE-derived features and four conventional clinical indices were obtained using automated bidirectional stepwise feature selection. Logistic regression (LR) was used for classification. Our optimum LR model reached 83.5% accuracy (84.5% sensitivity and 83.0% specificity). Our results suggest that MSE provides relevant information from oximetry that is complementary to conventional approaches. Therefore, MSE may be useful to improve the diagnostic ability of unattended oximetry as a simplified screening test for childhood OSAS.Sociedad Española de Neumología y Cirugía Torácica (SEPAR) project 153/2015Junta de Castilla y León (Consejería de Educación) y el Fondo Europeo de Desarrollo Regional (FEDER), projects (RTC-2015-3446-1) y (TEC2014-53196-R)Ministerio de Economía y Competitividad (MINECO) y FEDER, y el proyecto POCTEP 0378_AD_EEGWA_2_P de la Comisión Europea. L.National Institutes of Health (NIH) grant 1R01HL130984-01Ministerio de Asuntos Económicos y Transformación Digital, grant IJCI-2014-2266

Internal and near nozzle measurements of Engine Combustion Network "Spray G" gasoline direct injectors

[EN] Gasoline direct injection (GDI) sprays are complex multiphase flows. When compared to multi-hole diesel sprays, the plumes are closely spaced, and the sprays are more likely to interact. The effects of multi-jet interaction on entrainment and spray targeting can be influenced by small variations in the mass fluxes from the holes, which in turn depend on transients in the needle movement and small-scale details of the internal geometry. In this paper, we present a comprehensive overview of a multi-institutional effort to experimentally characterize the internal geometry and near-nozzle flow of the Engine Combustion Network (ECN) Spray G gasoline injector. In order to develop a complete pictitre of the near-nozzle flow, a standardized setup was shared between facilities. A wide range of techniques were employed, including both X-ray and visible-light diagnostics. The novel aspects of this work include both new experimental measurements, and a comparison of the results across different techniques and facilities. The breadth and depth of the data reveal phenomena which were not apparent from analysis of the individual data sets. We show that plume-to-plume variations in the mass fluxes from the holes can cause large-scale asymmetries in the entrainment field and spray structure. Both internal flow transients and small-scale geometric features can have an effect on the external flow. The sharp turning angle of the flow into the holes also causes an inward vectoring of the plumes relative to the hole drill angle, which increases with time due to entrainment of gas into a low-pressure region between the plumes. These factors increase the likelihood of spray collapse with longer injection durations.The X-ray experiments were performed at the 7-BM and 32-ID beam lines of the APS at Argonne National Laboratory. Use of the APS is supported by the U.S. Department of Energy (DOE) under Contract No. DE-AC02-06CH11357. Research was also performed at the Combustion Research Facility, Sandia National Laboratories, Livermore, California. Sandia National Laboratories is managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy National Nuclear Security Administration under contract DE-NA-0003525.Duke, DJ.; Kastengren, AL.; Matusik, KE.; Swantek, AB.; Powell, CF.; Payri, R.; Vaquerizo, D.... (2017). Internal and near nozzle measurements of Engine Combustion Network "Spray G" gasoline direct injectors. Experimental Thermal and Fluid Science. 88:608-621. https://doi.org/10.1016/j.expthermflusci.2017.07.015S6086218

High rate of uncovered struts in latest generation drug-eluting stents with durable, biodegradable polymer or lack of it 1 month after implantation

Introduction and objectives: Delayed vascular healing may induce late stent thrombosis. Optical coherence tomography (OCT) is useful to evaluate endothelial coverage. The objective of this study was to compare stent coverage and apposition in non-complex coronary artery lesions treated with durable polymer-coated everolimus-eluting stents (durable-polymer EES) vs biodegradable polymer-coated everolimus-eluting stents ( biodegradable-polymer EES) vs polymer-free biolimus-eluting stents (BES) 1 and 6 months after stent implantation. Methods: Prospective, multicenter, non-randomized study that compared the 3 types of DES. Follow-up angiography and OCT were performed 1 and 6 months later. The primary endpoint was the rate of uncovered struts as assessed by the OCT at 1 month. Results: A total of 104 patients with de novo non-complex coronary artery lesions were enrolled. A total of 44 patients were treated with polymer-free BES, 35 with biodegradable-polymer EES, and 25 with durable-polymer EES. A high rate of uncovered struts was found at 1 month with no significant differences reported among the stents (80.2%, polymer-free BES; 88.1%, biodegradable-polymer EES; 82.5%, durable-polymer EES; P =.209). Coverage improved after 6 months in the 3 groups without significant differences being reported (97%, 95%, and 93.7%, respectively; P =.172). Conclusions: In patients with de novo non-complex coronary artery lesions treated with durable vs biodegradable vs polymer-free DES, strut coverage and apposition were suboptimal at 1 month with significant improvement at 6 months

Time Course and Pattern of Metastasis of Cutaneous Melanoma Differ between Men and Women

Background: This study identified sex differences in progression of cutaneous melanoma. Methodology/Principal Findings: Of 7,338 patients who were diagnosed as an invasive primary CM without clinically detectable metastases from 1976 to 2008 at the University of Tuebingen in Germany, 1,078 developed subsequent metastases during follow up. The metastatic pathways were defined in these patients and analyzed using the Kaplan-Meier method. Multivariate survival analysis was performed using Cox modeling. In 18.7 % of men and 29.2 % of women (P,0.001) the first metastasis following diagnosis of primary tumor was locoregional as satellite/in-transit metastasis. The majority of men (54.0%) and women (47.6%, P = 0.035) exhibited direct regional lymph node metastasis. Direct distant metastasis from the stage of the primary tumor was observed in 27.3 % of men and 23.2 % of women (P = 0.13). Site of first metastasis was the most important prognostic factor of survival after recurrence in multivariate analysis (HR:1.3; 95 % CI: 1.0–1.6 for metastasis to the regional lymph nodes vs. satellite/in-transit recurrence, and HR:5.5; 95 % CI: 4.2–7.1 for distant metastasis vs. satellite/ in-transit recurrence, P,0.001). Median time to distant metastasis was 40.5 months (IQR, 58.75) in women and 33 months (IQR, 44.25) in men (P = 0.002). Five-year survival after distant recurrence probability was 5.2 % (95 % CI: 1.4–2.5) for men compared with 15.3 % (95 % CI: 11.1–19.5; P = 0.008) for women. Conclusions/Significance: Both, the pattern of metastatic spread with more locoregional metastasis in women, and th

Nocturnal Oximetry-based Evaluation of Habitually Snoring Children

Rationale: The vast majority of children around the world undergoing adenotonsillectomy for obstructive sleep apnea–hypopnea syndrome (OSA) are not objectively diagnosed by nocturnal polysomnography because of access availability and cost issues. Automated analysis of nocturnal oximetry (nSpO2), which is readily and globally available, could potentially provide a reliable and convenient diagnostic approach for pediatric OSA. Methods: DeidentifiednSpO2 recordings froma total of 4,191 children originating from13 pediatric sleep laboratories around the worldwere prospectively evaluated after developing and validating an automated neural network algorithm using an initial set of single-channel nSpO2 recordings from 589 patients referred for suspected OSA. Measurements and Main Results: The automatically estimated apnea–hypopnea index (AHI) showed high agreement with AHI from conventional polysomnography (intraclass correlation coefficient, 0.785) when tested in 3,602 additional subjects. Further assessment on the widely used AHI cutoff points of 1, 5, and 10 events/h revealed an incremental diagnostic ability (75.2, 81.7, and 90.2% accuracy; 0.788, 0.854, and 0.913 area under the receiver operating characteristic curve, respectively). Conclusions: Neural network–based automated analyses of nSpO2 recordings provide accurate identification of OSA severity among habitually snoring children with a high pretest probability of OSA. Thus, nocturnal oximetry may enable a simple and effective diagnostic alternative to nocturnal polysomnography, leading to more timely interventions and potentially improved outcomes.Supported in part by project VA037 U16 from the Consejer´ıa de Educacio´ n de la Junta de Castilla y Leo´ n and the European Regional Development Fund (FEDER), project RTC-2015-3446-1 from the Ministerio de Econom´ıa y Competitividad and FEDER, and project 153/2015 of the Sociedad Espan˜ ola de Neumolog´ıa y Cirug´ıa Tora´ cica (SEPAR). L.K.-G. is supported by NIH grant 1R01HL130984. M.F.P. was supported by a Fellowship Educational grant award from the Kingdom of Saudi Arabia. D.´A. was in receipt of a Juan de la Cierva grant from the Ministerio de Econom´ıa y Competitividad. The funders played no role in the study design, data collection, data analysis, interpretation, and writing of the manuscript

Clinical Practice Guideline on Melanoma From the Spanish Academy of Dermatology and Venereology (AEDV)

El diagnóstico y tratamiento del melanoma en atención especializada es un campo en el que se han producido numerosos cambios. El objetivo de esta guía es ofrecer a los dermatólogos españoles una referencia para resolver las dudas clínicas más frecuentes basándose en la evidencia actual. Para la realización de esta guía se escogió a miembros del Grupo Español de Dermato-Oncología y Cirugía con experiencia en el tratamiento de estos tumores y con interés en participar en la elaboración de la guía. Se hizo una adaptación de las guías de práctica clínica existentes mediante el método ADAPTE: inicialmente se resumió el proceso de atención y se elaboraron las preguntas clínicas relevantes. Se seleccionaron las guías mejor puntuadas mediante el instrumento AGREE II, realizando la búsqueda de las respuestas en dichas guías y elaborando las recomendaciones. Finalmente se sometió la guía a revisión externa. La guía se estructuró a partir de 21 preguntas clínicas que fueron seleccionadas por su relevancia, dado que se centran en aspectos que pueden plantear decisiones difíciles en el manejo del melanoma, y se han respondido empleando la evidencia obtenida de las mejores guías existentes. Entre las limitaciones de esta guía merece reseñarse que la evidencia es escasa para responder a algunas preguntas. En algunos aspectos el cambio es rápido y exige una actualización frecuente de la guía. Esta guía responde a preguntas habituales sobre el manejo del melanoma en la práctica clínica diaria, sirviendo a los dermatólogos como referencia en la toma de decisiones, siempre teniendo presente los recursos y preferencias del paciente

Allergic rhinitis and asthma: inflammation in a one-airway condition

BACKGROUND: Allergic rhinitis and asthma are conditions of airway inflammation that often coexist. DISCUSSION: In susceptible individuals, exposure of the nose and lungs to allergen elicits early phase and late phase responses. Contact with antigen by mast cells results in their degranulation, the release of selected mediators, and the subsequent recruitment of other inflammatory cell phenotypes. Additional proinflammatory mediators are released, including histamine, prostaglandins, cysteinyl leukotrienes, proteases, and a variety of cytokines, chemokines, and growth factors. Nasal biopsies in allergic rhinitis demonstrate accumulations of mast cells, eosinophils, and basophils in the epithelium and accumulations of eosinophils in the deeper subepithelium (that is, lamina propria). Examination of bronchial tissue, even in mild asthma, shows lymphocytic inflammation enriched by eosinophils. In severe asthma, the predominant pattern of inflammation changes, with increases in the numbers of neutrophils and, in many, an extension of the changes to involve smaller airways (that is, bronchioli). Structural alterations (that is, remodeling) of bronchi in mild asthma include epithelial fragility and thickening of its reticular basement membrane. With increasing severity of asthma there may be increases in airway smooth muscle mass, vascularity, interstitial collagen, and mucus-secreting glands. Remodeling in the nose is less extensive than that of the lower airways, but the epithelial reticular basement membrane may be slightly but significantly thickened. CONCLUSION: Inflammation is a key feature of both allergic rhinitis and asthma. There are therefore potential benefits for application of anti-inflammatory strategies that target both these anatomic sites