Stable finite elements analysis of viscous dusty plasma

In the context of analysis of dust acoustic (solitary) waves including viscosity, we introduce a finite elements formulation of the corresponding fluid dust-acoustic wave equations. With this objective, a Petrov-Galerkin weak form with unwinding is adopted. We consider a dusty unmagnetised plasma system consisting of negatively charged dust and Boltzmann electrons and ions. Nonlinearity of ion and electron number density in terms of a electrostatic potential is included. A fully-implicit time-integration is used (backward-Euler method) which requires the first derivative of the weak form. A three-field formulation is proposed, with the dust number-density, the electrostatic potential and the dust velocity being the unknown fields. Two numerical examples are introduced and results show great promise for the proposed formulation as a predictive tool in viscous dusty plasmas

Finite element analysis of plasma dust-acoustic waves

For dust acoustic solitary waves, we propose a finite element formulation of the fluid dusty plasma equations. To solve this continuum problem, a Petrov-Galerkin weak form with unwinding is applied. We consider an unmagnetised dusty plasma with negatively charged dust and Boltzmann distributions for electrons and ions. Nonlinearity of electron and ion number density as functions of the electrostatic potential is included. A fully-implicit time-integration is used (backward-Euler method) which requires the derivative of the weak form. A three-field formulation is introduced, with dust number-density, electrostatic potential and dust velocity being the unknown fields. We test the formulation with two numerical (2D and 3D)examples where convergence with mesh size is assessed. These establish the new formulation as a predictive tool in dusty plasmas

2,6-Diphenylpyridine

In the title compound, C17H13N, the dihedral angles between the pyridine ring and the phenyl rings are 29.68 (18) and 26.58 (17)°. In the crystal structure, the mol­ecules are linked by a weak C-H inter­action, leading to [01] chains. There are no further significant inter­molecular inter­actions

Perforated peptic ulcer: main factors of morbidity and mortality.

World J Surg. 2003 Jul;27(7):782-7. Perforated peptic ulcer: main factors of morbidity and mortality. Noguiera C, Silva AS, Santos JN, Silva AG, Ferreira J, Matos E, Vilaça H. Surgery Department, Surgery 1, Hospital Geral de Santo António, Instituto de Ciencias Biomédicas Abel Salazar, Largo do Prof. Abel Salazar, 4099-001 Oporto, Portugal. Abstract It is well stated in the literature that medical treatment for peptic ulcer is based on a combination of proton pump inhibitors (PPIs) and antibiotics to eradicate Helicobacter pylori. This treatment is associated with a high rate of immediate success and a low rate of recurrence at 12 months, although it is not effective in all patients. Peptic ulcer (PU) perforation is a serious problem that leads to high complication and mortality rates. Surgical treatment, with its various possibilities, constitutes the ideal treatment. Surgical intervention in these cases, however, can be directed to treating the perforation alone, or it can offer definitive treatment of the ulcer itself. With the hope of establishing why such complications and mortality were seen in the patients in our hospital population, we gathered the facts about PU perforations and the types of surgery performed. We studied 210 consecutive patients (150 men, 60 women) who had undergone surgery at our hospital because of perforation between January 1, 1990 and December 31, 2000. The patients' median age was 53.0 +/- 20.6 years (men 47.7 +/- 17.3 years; women 66.3 +/- 22.0 years). Altogether, 86 patients had significant associated illnesses, 62 were admitted more than 24 hours after the perforation, and 25 were admitted in shock. We performed resections in 10 patients; 88 patients were treated by suturing the perforation with or without a patch of epiploon; and 112 underwent a troncular vagotomy with drainage (VT + Dr). A total of 21 patients died (10%). Significant risk factors that led to complications were identified by statistical studies. They were a perforation that had been present more than 24 hours, the coexistence of significant associated illnesses, and resection surgery. The significant risk factors that led to death were the presence of shock at admission, the coexistence of significant illnesses, and resection surgery. There was no statistically significant difference concerning morbidity and mortality between simple closure of the perforation and definitive surgery (VT + Dr). PMID: 14509505 [PubMed - indexed for MEDLINE

Early gastric cancer: ten years of experience

World J Surg. 2002 Mar;26(3):330-4. Epub 2001 Dec 21. Early gastric cancer: ten years of experience. Nogueira C, Silva AS, Santos JN, Silva AG, Ferreira J, Matos E, Vilaça H. Surgery Department, Surgery 1, Hospital Geral de Santo António, Largo Prof. Abel Salazar, 4000 Oporto, Portugal. [email protected] Abstract Gastric cancer is a disease in which the main treatment is surgical extirpation. The modifications introduced in the surgical treatment over the last decades were accompanied by a clear increase of survival, which reaches global values of 61% at 5 years in Japan. One of the reasons that contribute to this improvement is early diagnosis of the lesions. In the period between January 1, 1990 and December 31, 1999 662 patients with gastric adenocarcinoma were treated in the Service of Surgery 1 of our hospital; 110 were refused surgical treatment. Of the resected patients, 91 (21.4%) were classified as early gastric cancer according to the definition of the Japanese Society of Digestive Endoscopy. There were 30 women and 61 men, with a median age of 60.2 +/- 15 years; 3 patients had a preoperative diagnosis of gastric ulcer; 2 others were operated without recent histology; and 1 patient was urgently resected for a bleeding ulcer. In all the remaining patients biopsy confirmed the presence of cancer (89%) or serious dysplasia (4.6%). The lesions had been distributed essentially in the medium 1/3 (48.3%) and distal 1/3 of the stomach. Subtotal gastrectomy was accomplished in 48 patients, total gastrectomy in 40, total desgastrogastrectomy in 3, and in 9 patients the surgery involved the spleen (8 patients) and the spleen and tail of the pancreas in 1 patient. Lymphadenectomy was not performed in 5 patients, lymph nodes by the first lymph node barrier were removed in 25 patients and by the second barrier in 61 patients (67%). Median tumor size was 26 +/- 1.8 mm. The lesion reached the mucosa in 46 patients and the mucosa and submucosa in 45. In 6 patients the removed lymph nodes were microscopically invaded (6.7%). Five patients died (5.7%). The median follow-up of the patients is 41 +/- 26 months; 7 patients died (8.1%) during this period; 4 died unequivocally of disease progression. The median survival of patients was 85% at 5 years and 80% at 10 years. In our series, survival was affected by the presence of invaded lymph nodes, not by the penetration in depth of the lesion or the size of the tumor. PMID: 11865370 [PubMed - indexed for MEDLINE

Vibration of Timoshenko Beams Using Non-classical Elasticity Theories

This paper presents a comparison among classical elasticity, nonlocal elasticity, and modified couple stress theories for free vibration analysis of Timoshenko beams. A study of the influence of rotary inertia and nonlocal parameters on fundamental and higher natural frequencies is carried out. The nonlocal natural frequencies are found to be lower than the classical ones, while the natural frequencies estimated by the modified couple stress theory are higher. The modified couple stress theory results depend on the beam cross-sectional size while those of the nonlocal theory do not. Convergence of both non-classical theories to the classical theory is observed as the beam global dimension increases

A Influência Da Cultura Local No Processo De Ensino E Aprendizagem De Matemática Numa Comunidade Quilombola

The process of teaching and learning in Quilombola communities has been widely discussed lately due to the recent inclusion of the modality of Quilombola School Education, which should represent a breakthrough for the educational process of these communities, bringing up their own school model that allows an approach to the specific knowledge to be taught. Thus, this paper presents results obtained in research on teaching and learning mathematics, using a qualitative research approach, in the form of case study, developed in a Quilombola school in a community of Santiago do Iguape - Ba. This study results indicate the need for an effective approach to mathematical knowledge present within each cultural group, as well as a teacher training in the perspective of Ethnomathematics. Therefore, we intend to contribute elements including the discussion of the teaching and learning of Mathematics to see which relationships can be established between the experience of particular cultural group of students and the teaching of this discipline.305697299

Validation of NoSAS (Neck, Obesity, Snoring, Age, Sex) score as a screening tool for obstructive sleep apnea: Analysis in a sleep clinic

Screening methods have become increasingly important due to the growing number of patients suspected of having obstructive sleep apnea (OSA) being referred to sleep clinics. The Lausanne NoSAS (Neck circumference, Obesity, Snoring, Age, Sex) score test is a simple, efficient, and easily employed tool enabling identification of individuals at risk for the disease. The score ranges from 0 to 17 and the patient has a high probability of OSA if they have a NoSAS score of 8 or higher.info:eu-repo/semantics/publishedVersio

Synthetic genetic oscillators demonstrate the functional importance of phenotypic variation in pneumococcal-host interactions.

Phenotypic variation is the phenomenon in which clonal cells display different traits even under identical environmental conditions. This plasticity is thought to be important for processes including bacterial virulence, but direct evidence for its relevance is often lacking. For instance, variation in capsule production in the human pathogen Streptococcus pneumoniae has been linked to different clinical outcomes, but the exact relationship between variation and pathogenesis is not well understood due to complex natural regulation. In this study, we use synthetic oscillatory gene regulatory networks (GRNs) based on CRISPR interference (CRISPRi) together with live cell imaging and cell tracking within microfluidics devices to mimic and test the biological function of bacterial phenotypic variation. We provide a universally applicable approach for engineering intricate GRNs using only two components: dCas9 and extended sgRNAs (ext-sgRNAs). Our findings demonstrate that variation in capsule production is beneficial for pneumococcal fitness in traits associated with pathogenesis providing conclusive evidence for this longstanding question