Boundary controllability for a 1D degenerate parabolic equation with a Robin boundary condition

In this paper we prove the null controllability of a one-dimensional degenerate parabolic equation with a weighted Robin boundary condition at the left endpoint, where the potential has a singularity. We use some results from the singular Sturm-Liouville theory to show the well-posedness of our system. We obtain a spectral decomposition of a degenerate parabolic operator with Robin conditions at the endpoints, we use Fourier-Dini expansions and the moment method introduced by Fattorini and Russell to prove the null controllability and to obtain an upper estimate of the cost of controllability. We also get a lower estimate of the cost of controllability by using a representation theorem for analytic functions of exponential type.Comment: arXiv admin note: substantial text overlap with arXiv:2304.00178, arXiv:2302.0119

The Applicability of the Eclectic Method on the Development of the Oral Production

Developing our students\u27 English oral expression in Public Institutions is a process that needs to be carefully analyzed by teachers. It is more than selected a method, it is more than following step by step what a theory says. It is going beyond our students\u27 needs. It is a deeply study of what a student really can do and needs to learn. Based on a post-method pedagogy which provides teachers the ability to break down barriers to the imposition of a specific method and make the teaching process more effective, this paper proposes the application of the eclectic method for the development of the oral expression of public high school students encouraging teachers to see the teaching process from a different and modern perspective. By analyzing the principles and features of this method, this paper describes the research made on a Public Institution with students in third year. With the goal of improving each one of the principal components of the English oral expression: range, accuracy, fluency, pronunciation and coherence, there were used selected methods, techniques and strategies based upon the students\u27 learning styles and needs. The observation and Interview techniques were used on data collection and the parameters of Inferential and descriptive statistic were applied in order to analyze the results achieved. They showed that even though not all of the group of the students could achieve the B1 level in reference to the Common European Framework and required by the Ministry of Education, a large number of them were able to increase their English oral expression. According to this data, this paper concludes that the selection of objectives, the modern teacher‘s and student\u27s role, the use of different but selected methods, the linguistic input activation and the contextualization had a significant impact on learners´ learning

The Effects on Toxicity of Circadian Patterning of Continuous Hepatic Artery Infusion

Long term continuous hepatic artery infusion of FUDR was carried out in 34 rats. In the animals who received a constant infusion schedule of 15mg/kg/day all died of toxicity with a mean survival of 9.3 days. If the pattern of the continuous infusion was changed so that over 60% of the infusion was given during the hours of 3pm to 9pm then all of the animals survived the 14 day infusion. If the maximum dose of infusion was changed so that 60% of the infusion was given at night from 3am to 9am the infusion became more toxic and all the animals died in a mean of 5.5 days. Pathologic sectioning of all the livers reflected the above outcomes with the greatest amount of hepatic necrosis in the animals on the night cycles. This study underscores the recent advances in chronobiology demonstrating that for continuous hepatic arterial infusions the timing of delivery is crucial in determining the toxicity

Prevalência de Doença Carotídea na Patologia Cérebro-Vascular Isquémica. O Papel do Eco-Doppler

BACKGROUND: Atherosclerotic carotid disease represents approximately 20% of the causes of ischemic stroke. Effective treatment options, such as endovascular or surgical revascularization procedures, are available. Doppler Ultrasound (DUS) is a non-invasive, inexpensive, routine exam used to evaluate the presence of internal carotid artery (ICA) stenosis. We retrospectively analysed the prevalence of severe atherosclerotic carotid disease in a population of patients with acute ischemic stroke/transitory ischemic attacks (TIAs), and the role of DUS in the detection of ICA stenosis and treatment decisions in these patients. METHODS: A total of 318 patients with ischemic stroke or TIAs was admitted to our stroke unit, and 260 patients were studied by DUS. ICA stenosis was evaluated by DUS according to peak systolic velocity. All DUS exams were performed by the same operator. ICA stenosis was further assessed in 43 patients by digital subtraction angiography (DSA) using NASCET criteria. RESULTS: Of the total 318 patients, 260 (82%) had DUS evaluation. Of the total 520 ICAs studied by DUS, degrees of ICA stenosis were: 0-29% n= 438 (84%); 30-49% n= 8 (2%); 50-69% n= 27 (5%); 70-89% n= 15 (3%); 90-99% n= 20 (4%); oclusão n= 14 (2%). Of the total 260 patients studied, 43 (16.5%) underwent DSA. Sensibility and specificity of DUS in the diagnosis of carotid stenosis over 70% were, respectively, 91% e 84%. Of the total 31 patients with significant carotid stenosis (70-99%), 23 (74%) underwent subsequent carotid revascularization procedures. DISCUSSION: DUS is an important screening test in our stroke unit, justifying its use as a routine exam for all patients with ischemic stroke/TIAs. Moreover, our results show the relevance of severe carotid disease in a population with acute ischemic stroke/TIAs (16.5%), with a total of 9% of patients being submitted to carotid revascularization procedures

Environmental drivers of diurnal visits by transient predatory fishes to Caribbean patch reefs

Video cameras recorded the diurnal visitation rates of transient (large home range) piscivorous fishes to coral patch reefs in The Bahamas and identified 11 species. Visits by bar jack Caranx ruber, mutton snapper Lutjanus analis, yellowtail snapper Ocyurus chrysurus, barracuda Sphyraena barracuda and cero Scomberomorus regalis were sufficiently frequent to correlate with a range of biophysical factors. Patch-reef visitation rates and fish abundances varied with distance from shore and all species except S. regalis were seen more frequently inshore. This pattern is likely to be caused by factors including close proximity to additional foraging areas in mangroves and on fore-reefs and higher abundances close to inshore nursery habitats. Visitation rates and abundances of C. ruber, L. analis, O. chrysurus and S. regalis also varied seasonally (spring v. winter), possibly as fishes responded to temperature changes or undertook spawning migrations. The abundance of each transient predator species on the patch reefs generally exhibited limited diurnal variability, but L. analis was seen more frequently towards dusk. This study demonstrates that the distribution of transient predators is correlated spatially and temporally with a range of factors, even within a single lagoon, and these drivers are species specific. Transient predators are considered an important source of mortality shaping reef-fish assemblages and their abundance, in combination with the biomass of resident predators, was negatively correlated with the density of prey fishes. Furthermore, transient predators are often targeted by fishers and understanding how they utilize seascapes is critical for protecting them within reserves

Total petroleum hydrocarbons in water, sediment, and Redbelly tilapia, Coptodon zillii in Shatt Al-Basrah Canal, Iraq

Water pollution is one of the most common global problems resulting from increased industrial and agricultural activities. Petroleum hydrocarbons have extremely dangerous to the aquatic environment. The total petroleum hydrocarbon (TPHs) was investigated in water, sediment, and muscles of Coptodon zillii at Abu Sakhir and Al-Zubair Bridge stations seasonally in the Shatt al-Basra Canal. The results showed a variation in the TPHs levels in the studied stations. In addition, a significant difference in the TPHs was recorded during the seasons in the water, and sediments between stations. The results showed significant differences in the TPHs in the muscles in the spring but no significant in other seasons between the two stations. The results of the lipid contents of fish revealed significant differences between the two studied stations in the fall, spring, and summer seasons but not significant in winter.&nbsp

Socioeconomic and demographic factors associated with failure in Helicobacter pylori eradication using the standard triple therapy

Aim: To evaluate the influence of socioeconomic and demographic factors on the eradication rate of H. pylori, using standard triple therapy Background: the efficacy of the standard triple therapy (STT) for H. pylori eradication has decreased with the rise of antibiotic resistance. Other factors could influence the eradication failure, although available results are conflicting. Methods: Retrospective study, including adults with H. pylori infection treated de novo with STT (proton pump inhibitor, amoxicillin and clarithromycin). Eradication success was assessed by 13C-urea breath test. Demographic and socioeconomics variables were evaluated and correlated with eradication treatment outcome. The confounder variables were controlled by logistic regression analysis. Results: Out of 902 patients with H. pylori diagnosis, 693 met inclusion criteria (average age 53 years; females 55.2%). Nonsignificant differences were observed in relation to economics income between rural and urban areas (p=0.316). The eradication rate of H. pylori was 71.1%: male 78.9% vs female 65.9%, urban area 73.4% vs rural area 64.1%. With reference to age, income and nationality, the eradication rates were similar in all groups. According to logistic regression analysis, females had almost twice more likelihood of eradication failure in relation to males (OR 1.92; 95%CI: 1.38-2.72); and rural residents had OR 1.55 (95%CI: 1.03- 2.33) for having eradication failure in contrast with urban population. Conclusion: Female gender and rural residence are factors associated with H. Pylori eradication failure with standard triple therapy

Height gradient approach for occlusion detection in UAV imagery

The use of Unmanned Aerial Vehicle (UAV) significantly increased in the last years. It is used for several different applications, such as mapping, publicity, security, natural disasters assistance, environmental monitoring, 3D building model generation, cadastral survey, etc. The imagery obtained by this kind of system has a great potential. To use these images in true orthophoto generation projects related to urban scenes or areas where buildings are present, it is important to consider the occlusion caused by surface height variation, platform attitude, and perspective projection. Occlusions in UAV imagery are usually larger than in conventional airborne dataset due to the low-altitude and excessive change in orientation due to the low-weight and wind effects during the flight mission. Therefore, this paper presents a method for occlusion detection together with some obtained results for images acquired by a UAV platform. The proposed method shows potential in occlusion detection and true orthophoto generation401W4263268International Conference on Unmanned Aerial Vehicles in Geomatic

Differential Stability of Aurein 1.2 Pores in Model Membranes of Two Probiotic Strains

Aurein 1.2 is an antimicrobial peptide from the skin secretion of an Australian frog. In the previous experimental work, we reported a differential action of aurein 1.2 on two probiotic strains Lactobacillus delbrueckii subsp. bulgaricus (CIDCA 331) and Lactobacillus delbrueckii subsp. lactis (CIDCA 133). The differences found were attributed to the bilayer compositions. Cell cultures and CIDCA 331-derived liposomes showed higher susceptibility than the ones derived from the CIDCA 133 strain, leading to content leakage and structural disruption. Here, we used molecular dynamics simulations to explore these systems at the atomistic level. We hypothesize that if the antimicrobial peptides organized themselves to form a pore, it will be more stable in membranes that emulate the CIDCA 331 strain than in those of the CIDCA 133 strain. To test this hypothesis, we simulated preassembled aurein 1.2 pores embedded into bilayer models that emulate the two probiotic strains. It was found that the general behavior of the systems depends on the composition of the membrane rather than the preassemble system characteristics. Overall, it was observed that aurein 1.2 pores are more stable in the CIDCA 331 model membranes. This fact coincides with the high susceptibility of this strain against antimicrobial peptide. In contrast, in the case of the CIDCA 133 model membranes, peptides migrate to the water-lipid interphase, the pore shrinks, and the transport of water through the pore is reduced. The tendency of glycolipids to make hydrogen bonds with peptides destabilizes the pore structures. This feature is observed to a lesser extent in CIDCA 331 due to the presence of anionic lipids. Glycolipid transverse diffusion (flip-flop) between monolayers occurs in the pore surface region in all the cases considered. These findings expand our understanding of the antimicrobial peptide resistance properties of probiotic strains.Fil: Balatti, Galo Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Domene, Carmen. University of Bath; Reino UnidoFil: Martini, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Pickholz, Mónica Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentin