Frequency upconversion involving triads and quartets of ions in a Pr3+/Nd3+ codoped fluoroindate glass

Frequency upconversion (UC) processes involving energy transfer (ET) among Nd 3+ and Pr 3+ ions in a fluoroindate glass are reported. In a first experiment, the excitation of Pr 3+ [transition 3H 4→ 1D 2] and of Nd 3+ [transition 4I 9/2→( 2G 7/2+ 4G 5/2)] was achieved with a dye laser operating in the 575-590 nm range. In a second experiment, the Nd 3+ ions were excited with the second harmonic of a Nd: YAG laser at 532 nm. The ET processes leading to UC in both experiments were studied by monitoring the blue fluorescence decay at 480 nm due to the transition 3P 0→ 3H 4 in Pr 3+. In the more relevant UC process, quartets of ions (Nd-Nd-Pr-Pr) are excited due to absorption of three laser photons by two Nd 3+ ions which transfer their energy to two Pr 3+ ions. Each Pr 3+ ion promoted to the 3P 0 level decays to the ground state emitting one photon in the blue region. This conclusion was achieved investigating the dependence of the UC fluorescence intensity as a function of laser intensity, samples concentrations, and temporal behavior of the UC signal. Other UC processes involving nonisoionic groups of three ions are also reported. © 2002 American Institute of Physics.

Clinical and surgical management of an aggressive cherubism treated with autogenous bone graft and calcitonin

Cherubism is a rare autosomal-dominant inherited syndrome and is usually self-limiting; it starts in early childhood and involutes by puberty. It is a benign fibroosseous disease, characterized by excessive bone degradation of the upper and lower jaws followed by development of fibrous tissue masses. The purpose of this clinical report is to describe a rare and aggressive form of cherubism on an adult female patient that has been treated in our Bioscience Center for Special Health Care Needs-CEBAPE. The patient was firstly submitted to the surgical procedure with partial curettage of the lesion, and the cavity was filled with autogenous cancellous bone and bone marrow grafts. Furthermore, the support treatment used was the administration of salmon calcitonin by nasal spray during the first year after the preconized procedure. At 4-year followup, we confirmed the stomatognathic system improvement and esthetic rehabilitation, which led to a significant increase in the patient's quality of life.

Aggressive osseous commitment result by keratocyst odontogenic tumour: case report, radiographic and clinical standpoints

Keratocystic odontogenic tumour (KCOT) previously known as odontogenic keratocyst was recently classified as a benign lesion characterized by an infiltrating pattern, local aggressiveness with the propensity to recurrence. It is thought to arise from the dental lamina. Pain is usually not associated with KCOT until swelling occurs, and it commonly affects the posterior mandible. Multiple KCOT are associated with nevoid basal cell carcinoma syndrome. This study reports an aggressive case of KCOT with destruction of the osseous tissue of the mandible, accentuated face asymmetry, dysphagia and dysphonia. It was managed with a defined protocol which entailed diagnosis, treatment with enucleation along with peripheral ostectomy and rehabilitation. A long-term follow-up schedule was provided to the patient to observe the recurrence behaviour of this cyst. In postoperative phase, no complication was noticed regarding wound healing and recurrence.

Mirabegron relaxes urethral smooth muscle by a dual mechanism involving β3-adrenoceptor activation and α1-adrenoceptor blockade

Mirabegron is the first β3-adrenoceptor (AR) agonist approved for treatment of overactive bladder syndrome (OAB). This study aimed to investigate the effects of β3-adrenoceptor (AR) agonist mirabegron in mouse urethra. The possibility that mirabegron exerts α1-AR antagonism was also tested in rat smooth muscle preparations presenting α1A- (vas deferens and prostate), α1D- (aorta) and α1B-AR (spleen). Functional assays were carried out in mouse and rat isolated tissues. Competition assays for the specific binding of [(3) H]Prazosin to membrane preparations of HEK 293 cells expressing each of the human α1-ARs, as well as β-AR mRNA expression and cyclic AMP measurements in mouse urethra were performed. Mirabegron produced concentration-dependent urethral relaxations that were right shifted by the selective β3-AR antagonist L 748,337, but unaffected by β1- and β2-AR antagonists (atenolol and ICI 118,551, respectively). Mirabegron-induced relaxations were enhanced by the phosphodiesterase-4 inhibitor rolipram, and this agonist stimulated cAMP synthesis. Mirabegron also produced rightward shifts in urethral contractions induced by the α1-AR agonist phenylephrine. Schild regression analysis revealed that mirabegron behaves as a competitive antagonist of α1-AR in urethra, vas deferens and prostate (α1A-AR, pA2  ≅ 5.6) and aorta (α1D-AR, pA2  ≅ 5.4), but not in spleen (α1B-AR). The affinities estimated for mirabegron in functional assays were consistent with those estimated in radioligand binding with human recombinant α1A- and α1D-ARs (pKi ≅ 6.0). The effects of mirabegron in urethral smooth muscle are the result of β3-AR agonism together with α1A / α1D-AR antagonism.

Experimentos com frenagem eletromagnética

In this work we study the behavior of the falling motion of neodymium magnets, inside conductive a metallic duct made of copper, aluminum, brass and bronze. We obtain, analyze and present results involving relationships between material and dynamical properties of falling neodymium magnets with the mechanical and electrical properties of conductive materials, such as mass, electrical resistivity, electrical conductivity, length and external diameter

Comparação termométrica entre preparos cavitários realizados com turbinas de alta-rotação e laser de Er:YAG

The aim of this study was to compare temperature increases produced by a well-known equipment, the high-speed handpieces, with a relatively new instrument, the Er:YAG laser (350 mJ/10 Hz). Thirty-five bovine mandibular incisors, which were reduced to an enamel/dentin thickness of 2,5 mm, were used. Cavity preparation was done till a depth of 2, 5 mm. A thermocouple was placed to read the temperature inside of the pulp chamber. Analysis was performed in these groups: I - high-speed handpiece without water-cooling (n=10); II - high-speed handpiece with water-cooling (n=10); III - Er:YAG laser without water-cooling (n=5); IV- Er:YAG laser with water-cooling (n=10) Group III had only 5 teeth because it was impossible to properly make the cavity preparations by the laser equipment without water cooling. The temperature increases were recorded in a computer linked to the thermocouples and the data of the groups I, II and IV were submitted to Dunn's multiple comparison test (p<0,05). The medium temperature increases were: 11,64ºC for group I, 0,96ºC for group II, 40,86ºC for group III and 2,9°C for group IV. There were no statistical differences between groups lI and IV, and these were different from group I. The cavity preparations made by the high-speed and the laser equipment generated very similar heat increases under water-cooling. The water-cooling is essential to avoid aggressive temperature increases, both when using the high-speed and the laser equipment, and with laser it is especially necessary for ablation of enamel

Antimicrobial susceptibility to b-lactams and metronidazole of microorganisms isolated from chronic and aggressive periodontitis

The objective of this study was to evaluate the microbial susceptibility to ß-lactams and metronidazole, and evaluate the production of ß-lactamases by microorganisms isolated from patients with chronic or aggressive periodontitis. The samples were obtained from 50 patients with periodontitis and microorganisms were isolated onto selective and nonselective culture media, identified by biochemical methods and tested for susceptibility to antimicrobial agents (amoxicillin, amoxicillin/clavulanate, cefoxitin, imipenem, metronidazole, penicillin G). The isolates were resistant to at least 1 mg/ml of any drug tested were evaluated to verify the production of ß-lactamases by the method of double layer (or biological) and chromogenic cephalosporin using nitrocefin. The results evidenced resistance to amoxicillin and penicillin G, while the susceptibility to association amoxicillin/clavulanate, imipenem and cefoxitin was widely disseminated among the organisms. Resistance to these drugs showed a clear correlation with the production of ß-lactamase in the majority of microbial groups.

Biologia reprodutiva de Hypsiboas lundii (Anura, Hylidae) em um fragmento de Cerrado no sudoeste de Minas Gerais

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

As representações sociais dos diretores das escolas estaduais da diretoria de ensino de Presidente Prudente - SP sobre o seu papel e sobre a escola pública

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise numérica de uma geometria de coletor solar para sistemas de aquecimento de água

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Risk factors for postoperative endoscopic recurrence in Crohn's disease: a Brazilian observational study

Introduction: Postoperative endoscopic recurrence (PER) is the initial event after intestinal resection in Crohn’s disease (CD), and after a few years most patients present with progressive symptoms and complications related to the disease. The identification of risk factors for PER can help in the optimization of postoperative therapy and contribute to its prevention. Methods: Retrospective, longitudinal, multicenter, observational study involving patients with CD who underwent ileocolic resections. The patients were allocated into two groups according to the presence of PER and the variables of interest were analyzed to identify the associated factors for recurrence. Results: Eighty-five patients were included in the study. The mean period of the first postoperative colonoscopy was 12.8 (3–120) months and PER was observed in 28 patients (32.9%). There was no statistical difference in relation to gender, mean age, duration of CD, family history, previous intestinal resections, smoking, Montreal classification, blood transfusion, residual CD, surgical technique, postoperative complications, presence of granulomas at histology, specimen extension and use of postoperative biological therapy. The preoperative use of corticosteroids was the only variable that showed a significant difference between the groups in univariate analysis, being more common in patients with PER (42.8% vs. 21%; p = 0.044). Conclusions: PER was observed in 32.9% of the patients. The preoperative use of corticosteroids was the only risk factor associated with PER in this observational analysis.

Avaliação dos riscos assistenciais relacionados ao uso de equipamentos hospitalares na unidade de terapia intensiva de adultos de um hospital público da cidade de São Paulo, Brasil

Pós-graduação em Bases Gerais da Cirurgia - FMB

Airport Bird Threat in North America from Large Flocking Birds (geese) (as Viewed by an Engine Manufacturer)--Part 1

In worldwide aviation operations, bird collisions with aircraft and ingestions into engine inlets present safety hazards and financial loss through equipment damage, loss of service and disruption to operations. The problem is encountered by all types of aircraft, both military and commercial. Modern aircraft engines have achieved a high level of reliability while manufacturers and users continually strive to further improve the safety record. A major safety concern today includes common-cause events which involve significant power loss on more than one engine. These are externally-inflicted occurrences, with the most frequent being encounters with flocks of birds. Most frequently these encounters occur during flight operations in the area on or near airports, near the ground instead of at cruise altitude conditions. This paper focuses on the increasing threat to aircraft and engines posed by the recorded growth in geese populations in North America. Service data show that goose strikes are increasing, especially in North America, consistent with the growing resident geese populations estimated by the United States Department of Agriculture (USDA). Airport managers, along with the governmental authorities, need to develop a strategy to address this large flocking bird issue. This paper also presents statistics on the overall status of the bird threat for birds of all sizes in North America relative to other geographic regions. Overall, the data shows that Canada and the USA have had marked improvements in controlling the threat from damaging birds - except for the increase in geese strikes. To reduce bird ingestion hazards, more aggressive corrective measures are needed in international air transport to reduce the chances of serious incidents or accidents from bird ingestion encounters. Air transport authorities must continue to take preventative and avoidance actions to counter the threat of birdstrikes to aircraft. The primary objective of this paper is to increase awareness of, and focus attention on, the safety hazards presented by large flocking birds such as geese. In the worst case, multiple engine power loss due to large bird ingestion could result in an off-airport forced landing accident. Hopefully, such awareness will prompt governmental regulatory agencies to address the hazards associated with growing populations of geese in North America.

ECOLOGICAL CONTROL OF BIRD HAZARD TO AIRCRAFT

The Canadian Wildlife Service has had twenty-five years experience with the problem caused by bird contacts with aircraft. I experienced my first bird strike, while flying as an observer on a waterfowl survey in August, 1940. Officers of the Service investigated bird problems at airports at Yarmouth, Nova Scotia, and Cartierville, Quebec, in the late 1940's. Those incidents involving gulls and low speed piston-engined aircraft caused minor damage to the aircraft but considerable disturbance to the operators. As aircraft speeds increased and airports became more numerous and busier the problem increased in extent and complexity. By 1960 it was apparent that the problem would grow worse and that work should be directed toward reducing the number of incidents. In 1960 an electra aircraft crashed at Boston, Massachusetts, killing 61 passengers. Starlings were involved in the engine malfunction which preceded the crash. In November, 1962 a viscount aircraft was damaged by collision with two swans between Baltimore and Washington and crashed with a loss of 17 lives. Those incidents focused attention on the bird hazard problem in the United States.

Parabiosis between basal fungus-growing ants (Formicidae, Attini)

We describe the first observation of parabiosis between two Attini ants (Apterostigma urichii Forel and Cyphomyrmex faunulus Wheeler) found in northern Manaus, AM, Brazil. Complete, mature colonies of both species were found in a single cavity inside a rotten log, sharing and tending a single combined fungus garden, made up of two distinct halves, each cultivated by one species. Workers of one species often antennated workers of the other species and showed no aggression toward each other or toward each other`s workers, queens, or immatures. Laboratory observations suggest that immatures of both species feed on hyphae from either half of the fungus garden. We were not able to find other parabiotic pairs involving the same species in the same locality, although we found colonies of both species sharing trails and foraging territories.