461 research outputs found
Investigation on dynamic VOC production from industrial, high solids content emulsion polymerizations
Volatile Organic Compounds (VOC) pose a serious threat to human health and the environment. Unfortunately, many processes from fine chemistry involve VOCs as reagents, solvents, products or by-products. International standards and market requirements keep asking for lower VOC content in commercial goods, with the final aim of VOC-free products. Accomplishing such a task is a challenge because VOCs, due to their high vapour pressure, are hard to remove with traditional industrial methods, such as vacuum stripping or absorption. For this reason, it is important to know and understand how VOCs evolve throughout a chemical reaction. In this field, adhesives, which are usually developed exploiting polymerizations, represent an interesting subject, due to the complexity of their industrial synthesis: VOCs appear as reagents (monomers), conversion enhancers (post-polymerization), and by-products (hydrolysis and small chains). In this work, a study on the evolution and content of VOCs of an industrial recipe involving emulsion polymerizations is carried out. The industrial recipe is characterized by high solids content (about 70% w/w) and is mainly composed of 2-ethylhexyl acrylate (up to 50% w/w), anionic and nonionic surfactants. The evolution of the main VOCs found under different working conditions is discussed. The main VOCs found are acetaldehyde, acetone, t-butanol, vinyl acetate, butanol, methyl-methacrylate, butyl acrylate, 2-ethyl-exyl-alcohol, 2-ethyl-exyl- acetate and 2-ethyl-exyl-acrylate
Hyperpolarizability and operational magic wavelength in an optical lattice clock
Optical clocks benefit from tight atomic confinement enabling extended
interrogation times as well as Doppler- and recoil-free operation. However,
these benefits come at the cost of frequency shifts that, if not properly
controlled, may degrade clock accuracy. Numerous theoretical studies have
predicted optical lattice clock frequency shifts that scale nonlinearly with
trap depth. To experimentally observe and constrain these shifts in an
Yb optical lattice clock, we construct a lattice enhancement cavity
that exaggerates the light shifts. We observe an atomic temperature that is
proportional to the optical trap depth, fundamentally altering the scaling of
trap-induced light shifts and simplifying their parametrization. We identify an
"operational" magic wavelength where frequency shifts are insensitive to
changes in trap depth. These measurements and scaling analysis constitute an
essential systematic characterization for clock operation at the
level and beyond.Comment: 5 + 2 pages, 3 figures, added supplementa
EVALUATION OF LIVER PARENCHYMA AND PERFUSION USING DYNAMIC CONTRAST-ENHANCED COMPUTED TOMOGRAPHY AND CONTRAST-ENHANCED ULTRASONOGRAPHY IN CAPTIVE GREEN IGUANAS (IGUANA IGUANA) UNDER GENERAL ANESTHESIA
Background: Contrast-enhanced diagnostic imaging techniques are considered useful in veterinary and human
medicine to evaluate liver perfusion and focal hepatic lesions. Although hepatic diseases are a common occurrence
in reptile medicine, there is no reference to the use of contrast-enhanced ultrasound (CEUS) and contrast-enhanced
computed tomography (CECT) to evaluate the liver in lizards. Therefore, the aim of this study was to evaluate the
pattern of change in echogenicity and attenuation of the liver in green iguanas (Iguana iguana) after administration
of specific contrast media.
Results: An increase in liver echogenicity and density was evident during CEUS and CECT, respectively. In CEUS, the
mean \ub1 SD (median; range) peak enhancement was 19.9% \ub1 7.5 (18.3; 11.7-34.6). Time to peak enhancement was
134.0 \ub1 125.1 (68.4; 59.6-364.5) seconds. During CECT, first visualization of the contrast medium was at 3.6 \ub1 0.5
(4; 3-4) seconds in the aorta, 10.7 \ub1 2.2 (10.5; 7-14) seconds in the hepatic arteries, and 15 \ub1 4.5 (14.5; 10-24) seconds
in the liver parenchyma. Time to peak was 14.1 \ub1 3.4 (13; 11-21) and 31 \ub1 9.6 (29; 23-45) seconds in the aorta and
the liver parenchyma, respectively.
Conclusion: CEUS and dynamic CECT are practical means to determine liver hemodynamics in green iguanas.
Distribution of contrast medium in iguana differed from mammals. Specific reference ranges of hepatic perfusion
for diagnostic evaluation of the liver in iguanas are necessary since the use of mammalian references may lead the
clinician to formulate incorrect diagnostic suspicions
A dedicated protocol and environment for central venous catheter removal in pediatric patients affected by oncohematological diseases
The removal of long-term central venous catheters (CVCs) is not performed according to evidence-based guidelines, thus conveying the message that it is a procedure of secondary importance. Our study aims at comparing the experience at Bambino Gesù Pediatric Hospital before and after the implementation of a dedicated protocol and the identification of a specific area to perform such a procedure under the so-called nonoperating room anesthesia (NORA)
PO-485 Low abundance circulating proteins in giant cell tumours of bone
Introduction Circulating low-abundance proteins/fragments generating from tumour cells and tissues, represent the most important source of cancer biomarkers useful for early diagnosis and prognosis. Giant cell tumour of bone (GCT) is a benign neoplasm occurring in the long bone and in the axial skeleton of young adults. Approximately 5% of GCT develop pulmonary metastases. Although many biomarkers have been proposed, identification of circulating low abundance molecules may be useful to predict metastasis with a non invasive method. Material and methods The hydrogel nanoparticles technique followed by mass spectrometry was used to detect low molecular weight serum proteins or protein fragments in serum of 20 GCT patients with different clinical course and in 10 healthy sera used as control. The most representative low-abundant de novo or differentially abundant proteins were submitted to String database in order to define protein-protein interaction network. Cluster analysis was performed to identify prognostic groups of patients with similar abundance of proteins that significantly discriminate between the groups. Results and discussions For the 25 low-abundant de novo or differentially abundant proteins identified, we recognised that the top interconnected pathways included protein activation cascade, wound healing, blood coagulation, cell-substrate adhesion. Proteoma cluster analysis separated metastasis-free from metastatic GCT patients in two well-defined groups where serum levels of signalling transduction mediators and regulators of kinase activity presented a high discriminatory power. Increased expression of proteins STAT5B, GRB2 and OXSR1 was related to a higher probability of metastasis. Conclusion In conclusion, using a no invasive technique, we identified differentially abundant serum biomarkers, also providing prognostic information in patients with GCT of bone. Future studies are ongoing to establish the interplay between these biomarkers in order to fully understand the mechanism involved in tumour development and to focus on the planning of tailored therapies that should be more effective and less toxic
FORMAÇÃO DE VÍNCULOS PROFISSIONAIS PARA O TRABALHO EM EQUIPE NA ENFERMAGEM
This article resulted from research that aimed to build a strategy of team work in nursing, to promote interpersonal relationships (Professional ties), to reach a therapeutic care committed to users of health services. The methodology is supported by the constructivist current and included the following phases: Interview and observation. After the data analysis these themes emerged: Individual and group position in the micro area of activity; movement of group relationships; communication process; continuing education; professional competence. Strategies for team work in nursing are based on the theoretical foundations of the dynamics of group interplay, providing a new look at the management role of the nurse in the creation and establishment of professional links, in which interpersonal relationships can promote critical, reflective, and participatory praxis.Este artículo es resultado de la investigación que tuvo como objetivo construir una estrategia de trabajo en equipo en enfermería para favorecer las relaciones interpersonales, o sea, los vínculos profesionales, para el alcance de un cuidado terapéutico comprometido con las personas usuarias de los servicios de salud. La metodología tiene respaldo en la corriente constructivista y contó con las siguientes fases: entrevista y observación. Después del análisis de los datos surgieron los temas: posición individual y grupal en el microespacio de actuación; movimiento de las relaciones grupales; proceso de comunicación; educación continuada; competencia profesional. Las estrategias para el trabajo en equipo en enfermería se basan en los fundamentos teóricos de la dinámica de las interrelaciones grupales, determinando una nueva mirada para la función gerencial del enfermero, a partir de la formación y afirmación de los vínculos profesionales que agreguen, en los cuales las relaciones interpersonales puedan favorecer una praxis crítica, reflexiva y participativa.Este artigo é resultado da investigação que teve como objetivo construir uma estratégia de trabalho em equipe na enfermagem, para favorecer as relações interpessoais, ou seja, os vínculos profissionais, para o alcançe de um cuidado terapéutico comprometido com os usuários dos serviços de saúde. A metodologia tem o respaldo na corrente construtivista e conto com as seguintes fases: entrevista e observação. Depois da análise dos dados surgiram os temas: posição individual e grupal no micro espaço de atuação; movimiento das relações grupais; proceso de comunicação; educação continuada; competencia profissional. As estratégias para o trabalho na equipe em enfermagem tem base nos fundamentos teóricos da dinâmica das interrelações grupais, determinando um novo olhar para a função gerencial do enfermeiro, a partir da formação e afirmação dos vínculos profissionais, nos quais as relações interpessoais podem favorecer uma praxis crítica, reflexiva e participativ
Capacity building efforts for rabies diagnosis in resource-limited countries in Sub-Saharan Africa: a case report of the central veterinary laboratory in Benin (Parakou)
Rabies has been listed as a priority zoonotic disease in many African countries and the countdown to reach the goal of eliminating dog-mediated human rabies deaths by 2030 means that disease control measures need to be applied fast. In this context, an essential pillar of any national plan to control rabies is the implementation of reliable diagnostic techniques to ensure the success of field surveillance systems. Although many African countries have received international support for the control of rabies-some countries, like Benin, have not received a similar level of support. Indeed, until 2018, Benin was not able to diagnose rabies and rabies diagnosis in animals as well as humans relied solely on observed clinical symptoms. Although the Central Veterinary Laboratory (CVL) of Parakou had the equipment to implement two recommended tests, the lack of specific reagents and skills prevented the implementation of a rabies diagnostic service. Here we present the joint efforts of the national authorities in Benin, intergovernmental agencies, and non-governmental organizations to assess the strengths and weaknesses of the government's rabies control efforts. We have applied the Stepwise Approach toward Rabies Elimination (SARE) analysis, implemented rabies diagnostic capacities at the CVL of Parakou, characterized strains of rabies virus circulating in Benin, and finally integrated an inter-laboratory comparison program
- …