Adaptive optics control with multi-agent model-free reinforcement learning.

We present a novel formulation of closed-loop adaptive optics (AO) control as a multi-agent reinforcement learning (MARL) problem in which the controller is able to learn a non-linear policy and does not need a priori information on the dynamics of the atmosphere. We identify the different challenges of applying a reinforcement learning (RL) method to AO and, to solve them, propose the combination of model-free MARL for control with an autoencoder neural network to mitigate the effect of noise. Moreover, we extend current existing methods of error budget analysis to include a RL controller. The experimental results for an 8m telescope equipped with a 40x40 Shack-Hartmann system show a significant increase in performance over the integrator baseline and comparable performance to a model-based predictive approach, a linear quadratic Gaussian controller with perfect knowledge of atmospheric conditions. Finally, the error budget analysis provides evidence that the RL controller is partially compensating for bandwidth error and is helping to mitigate the propagation of aliasing.

Re-emergence of rabies virus maintained by canid populations in Paraguay.

Paraguay has registered no human cases of rabies since 2004, and the last case in dogs, reported in 2009, was due to a variant maintained in the common vampire bat "Desmodus rotundus". In 2014, a dog was diagnosed as positive for rabies with aggression towards a boy and all required measures of control were successfully adopted. Epidemiological investigation revealed that the dog was not vaccinated and had been attacked by a crab-eating fox, "zorro" (Cerdocyon thous). The sample was diagnosed by the Official Veterinary Service of the Country and sent to the Center on Rabies Research from the University of São Paulo, Brazil, for antigenic and genetic characterization. A second sample from a dog positive for rabies in the same region in 2015 and 11 samples from a rabies outbreak from Asuncion in 1996 were also characterized. The antigenic profile of the samples, AgV2, was compatible with one of the variants maintained by dogs in Latin America. In genetic characterization, the samples segregated in the canine (domestic and wild species)-related group in an independent subgroup that also included samples from Argentina. These results and the epidemiology of the case indicate that even with the control of rabies in domestic animals, the virus can still circulate in wildlife and may be transmitted to domestic animals and humans, demonstrating the importance of continuous and improved surveillance and control of rabies, including in wild species, to prevent outbreaks in controlled areas.

Tratamiento lapascópico de las fístulas biliodigestivas y del síndrome de Mirizzi tipo II / Laparoscopic treatment of internal biliary fistulas

Antecedentes: Las fístulas biliares son una rara complicación de la patología biliar (1 por ciento al 2 por ciento). Las controversias se plantean en la estrategia y en el abordaje quirúrgico. Objetivo: Evaluar la utilidad y resultados alejados del abordaje laparoscópico en el tratamiento de las fístulas biliares internas y del síndrome de Mirizzi tipo II. Lugar de aplicación: Hospital privado de la comunidad. Diseño: Estudio retrospectivo y descriptivo. Población: Se evaluó en forma retrospectiva los pacientes con diagnóstico de fístula biliar entre noviembre de 1991 y diciembre de 2004 excluyéndose aquellos pacientes con origen neoplásico de la fístula. Método: De 6108 colecistectomías videolaparoscóoicas, se diagnosticó fístula biliar interna en 38 pacientes (0,62 por ciento). Sexo femenino 28 (75,6 por ciento). Se trataron de 21 fístulas colecistoduodenales, 12 colecistocoledocianas (Mirizzi Tipo II), 4 colecistocolónicas y una fístula colecistoduodenal y colecistocoledociana asociada. Resultados: La estadía hospitalaria de 4,8 días (r: 2-11). Tiempo operatorio promedio: 183 minutos (r: 110-300). Se realizó colangiografía en el 100 por ciento de los pacientes. Morbilñidad en 8 pacientes (21,05 por ciento). Un paciente presentó una lesión quirúrgica de la vía bibliar que fue advertida y reparada en el intraoperatorio mediante una hepaticoyeyuno anastomosis. No hubo reoperaciones y un paciente falleció por una neumonía intrahospitalaria. Conversión en 7 pacientes (18,4 por ciento). En el seguimiento alejado un paciente presentó litiasis residual resuelta mediante CPRE y dos pacientes presentaron ca. de vesícula. Conclusiones: Las fístulas biliares internas son infrecuentes. El abordaje videolaparoscópico ofrece las ventajas de un procedimiento mini-invasivo, con buenos resultados alejados. Su utilidad es factible con un entrenamiento adecuado

[Health care and communication with the terminal cancer patient and his family in a health area]. / Atención sanitaria y comunicación con el enfermo oncológico en situación terminal y su familia en un área de salud.

OBJECTIVES: To know the clinical, essential and communication characteristics of the terminal cancer patient care in a health district. DESIGN: Cross-sectional descriptive study. PLACEMENT: Vth health district of Asturias (Spain). PATIENTS AND PARTICIPANTS: 107 cancer patients dead in the first term of 1995 and their families. MEASUREMENT AND MAIN RESULTS: Revision of hospital and primary care health centres clinical records and personal interview with the patient's main carer by closed questionnaire, taken place between August and October of 1996. We revised 107 clinical records interviewing 54 relatives. 50% of the patients died at home, 17% in a palliative care partially dedicated hospital. 81% of patients suffered from pain in some moment of their process, being controlled in 69%, using morphine in 66% of cases with pain (mode and median of dose 60 mg/24 hours VO). Pain evaluation scales were registered in 32% of cases, improving the pain control (p < 0.01). 30% of carers were told of their relative cancer diagnosis in a corridor. 57% of carers were advised on symptoms that the patient could suffer; these patients were interned in hospital in a smaller proportion (p = 0.02) and attended less the casualty department (p = 0.02). 19% of patients were informed about their diagnosis, using less health resources (less hospitalizations, p = 0.06). CONCLUSIONS: We use low doses of morphine. There is a low register of pain valoration scales, although they improve its control. Two thirds of patients dye in an proper place. Communication with the patients and their families is insufficient. Among other factors, the patient who knows his diagnosis uses less health resources.

A fluorescent temperature probe based on the association between the excited states of 4-(N,N-dimethylamino)benzonitrile and beta-cyclodextrin.

A temperature probe based on the fluorescence properties of the two excited states of 4-(N,N-dimethylamino)benzonitrile (DMABN) in equilibrium with beta-cyclodextrin (CD) in aqueous solution is presented. The fluorescence intensity of the Franck-Condon excited state (FB) as a function of temperature shows a straight line with a correlation better than 0.99 in the 283-308 K temperature interval. On the other hand, the fluorescence intensity of the twisted internal charge-transfer state (FA) remains constant in the same temperature interval because the binding of DMABN in the A* state to CD is isoenthalpic and entropy driven. It is found that the FA/FB ratio is independent of the excitation intensity at a specified temperature, shows a linear relationship with temperature, and allows temperature measurements with a resolution of +/- 2.5 K.

[Eradication of Helicobacter pylori in peptic ulcer and chronic gastritis. A randomized clinical trial]. / Erradicación del Helicobacter pylori en úlcera péptica y gastritis crónica. Ensayo clínico aleatorio.

BACKGROUND: The Helicobacter pylori (Hp) is found in patients with gastritis and peptic ulcer approximately in up to 80 percent. The eradication rates of 80 to 90 percent are achievable with some regimens. AIMS: Evaluate two regimens for H pylori eradication in gastritis and peptic ulcer. METHODS: Patients more than 20 years old with gastritis, gastric and duodenal ulcer disease and H pylori positive entered the study. We investigated prior history of peptic ulcer and hemorrhage, NSAID's use, smoking, alcoholism and epigastric pain. Endoscopy was performed before and at the end of the 8-12 weeks treatment, biopsies were taken from the antrum for Hp histological detection. Patients were randomly assigned to receive bismuth-metronidazole-tetracycline-ranitidine or bismuth-metronidazole-amoxicillin-ranitidine during two weeks. STATISTICAL ANALYSIS: chi square and multivariate analysis. RESULTS: One hundred and eighteen patients were included in this study, 52% male and 48% female with mean age of 47 +/- 16 years. History of peptic ulcer and bleeding was present in 79% and 62% respectively. NSAID's, and tobacco use among all patients was 49%, and 30%. Epigastric pain, melena and hematemesis was present in 90%, 47% and 24% respectively. H pylori eradication treatment was successful in 70% in both regimens (pNS). Was no related to age, tobacco and alcohol for Hp eradication (pNS), and NSAID's use was inversely related to Hp eradication (p < 0.05). Persistent peptic ulcer was seen in 23%. CONCLUSIONS: Eradication treatment was successful in 70% (p NS). Peptic ulcer refractory in 23% of patients and NSAID's use was inversely related to Hp eradication (p 0.05).

Outcome of pediatric intensive care at six centers in Mexico and Ecuador.

OBJECTIVE: To improve understanding of the causes of morbidity and mortality among critically ill children in the countries studied. DESIGN: Survey of hospital records between 1992 and 1994. SETTING: Six pediatric intensive care units (ICUs) (four ICUs in Mexico City and two ICUs in Ecuador). PATIENTS: Consecutive patients (n = 1,061) admitted to the units studied. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The mortality rate for low-risk patients (pediatric Risk of Mortality [PRISM] score of < or = 10, n = 701) was more than four times the rate predicted by the PRISM score (8.1% vs. 1.8%, p < .001), with an additional 11.3% of this group incurring major morbidity. The mortality rate for moderate-risk patients (PRISM scores of 11 to 20, n = 232) was more than twice predicted (28% vs. 12%, p < .001). For low-risk patients, death was significantly associated with tracheal intubation, central venous cannulation, pneumonia, age of < 2 months, use of more than two antibiotics, and nonsurgical diagnosis (after controlling for PRISM score). Central venous cannulation and tracheal intubation in the lower-risk groups were performed more commonly in units in Mexico than in one comparison unit in the United States (p < .001). CONCLUSIONS: For six pediatric ICUs in Mexico and Ecuador, mortality was significantly higher than predicted among lower-risk patients. Tracheal intubation, central catheters, pneumonia, sepsis, and nonsurgical status were associated with poor outcome for low-risk groups. We speculate that reducing the use of invasive central catheters and endotracheal intubation for lower-risk patients, coupled with improved infection control, could lower mortality rates in the population studied.

Rabía; a proposito de dos casos clínicos

Se presentan los casos clinicos de dos ninos afectados

Lipids in diabetic and nondiabetic hemodialysis and CAPD patients.

To examine the question of "accelerated atherogenesis" in ESRD patients, the authors conducted a lipid survey among their hemodialysis and CAPD populations and evaluated data relevant to the lipid and diabetic status of these groups. Interestingly, longer duration of hemodialysis in nondiabetic patients was associated with lower cholesterol but not HDL, which may reflect diminished cardiac risk and mortality in the long-term survivors. Diabetic patients showed lower HDL but no cholesterol change with longer duration on hemodialysis. Type I diabetics showed the highest HDL and lowest risk ratio and a strong inverse correlation between PTH and HDL. This study highlights the role of lipids in the atherogenesis of uremia and serves as a baseline for a longitudinal study.

Apparent bond strength of nonnoble alloy-porcelain combinations.

The apparent bond strengths of four porcelains and five nonnoble alloys were determined. On the basis of the data, the following conclusions can be drawn: The use of Vita, Ceramco, or Will-Ceram porcelains with Rexillium III, Pentillium, or Bak-On-NP alloy gave similar bond strength values. With the exception of Unibond alloy, the bond strength values obtained with Biobond porcelain were lower than those obtained with the other porcelain materials. The ceramometal bond strength values obtained with Unibond alloy were similar with all of the porcelains tested. The continued availability of a bewildering array of new alloys and porcelains suggests the urgent need for research designed to determine the bonding mechanisms and compatibility of various porcelain-alloy combinations. The data from this investigation provide criteria for the rational selection of bond strength-compatible porcelains and alloys for clinical use.