Equidad y transformación productiva: un enfoque integrado

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Reformas pensionales y costos fiscales en Colombia

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Sintering temperature influence on microwave dielectric properties of TiO2-ZrO2 ceramics

Dielectric ceramics have been widely investigated and used for microwave applications such as resonators and filters. The present study deals with the influence of sintering temperature on microwave dielectric properties of TiO2 ceramics with 10, 20, and 30 wt% ZrO2. Three compositions have been developed through mixing procedures and then tested for each sintering temperature: 1500 and 1400°C. X-ray diffraction and scanning electron microscopy are carried out aiming to explain the ceramic behavior of each sample. The dielectric constants of different ceramics for both temperatures varied from 85.4 to 62.6, while their quality factor due to dielectric losses varied from 3110 to 1630. The Q decrease is attributed to the non uniform grain growth and to the obtained crystalline phases. The best microwave parameters were obtained for the ceramics sintered at 1400°C, which can be applied in microwave circuits as dielectric resonators. © (2010) Trans Tech Publications.

Mucocele of the glands of Blandin-Nuhn-clinical, pathological, and therapeutical aspects

Purpose: This study aims to review anatomical, clinical, and pathological concepts as well as to discuss the most adequate therapeutic approach to the mucoceles of the glands of Blandin-Nuhn. Discussion: The glands of Blandin-Nuhn are localized in the ventral part of the tongue, next to the apex in the lingual median plane. Development of a mucocele in this site is rarely seen; besides, as the glands of Blandin-Nuhn are not encapsulated and are directly overlapped to the muscle tissues, their manipulation tends to be different from the other oral mucoceles. Conclusion: As Blandin-Nuhn mucoceles are uncommon and their clinical appearance could be similar to other lesions, it is important that health professionals know their clinical and histopathological features to avoid having them misdiagnosed. © 2010 Springer-Verlag.

Orbitoethmoidal impacted injury by kitchen knife causing abducens nerve palsy

Introduction: Impacted knife injuries in the maxillofacial region are rare and infrequently reported. In cases of injury involving orbit or eye, these reports are even rarer. Discussion: Damage to the orbital contents may result in a rupture of the globe, extraocular muscle injury, lacrimal gland damage, and others. Orbital foreign bodies are not only difficult to detect, and clinical features vary according to its size, characteristics, shape, penetrating method, and site. In this report, a case of abducens nerve palsy after orbitoethmoidal knife injury is presented. © 2010 Springer-Verlag.

Microwave-assisted hydrothermal synthesis of ZnO powders with different reagents

In this work, zinc oxide powders were synthesized by microwave-assisted hydrothermal method in basic medium. These powders were analyzed by X-ray diffraction (XRD), Field-emisson gum scanning electron microscopy (FEG-SEM), Ultraviolet-visible (UV-vis) absorption spectroscopy and photoluminescence (PL) measurements. XRD pattern confirmed that the pure ZnO phases were obtained after MH processing performed at 130°C/ 1h. FEG-SEM micrographs reveals that these nanostructures are made up of ZnO plates. UV-vis results were employed to determine the optical band gap these materials. Also, it showed existence of photoluminescence (PL) in the different zinc powders. An orange PL emission when excited by 350 nm wavelength at room temperature was observad in the different powders.

Multiple brain abscess from dental origin: Case report and literature review

Background: Brain abscess of dental origin is a rare situation and deserves attention due to its high mortality rate even when adequate treatment is done. Few reports are available when dental origin is the main cause of this infection. Case report: We present the case of a 70-year-old man diagnosed with cerebral abscess caused by apical lesions located at superior and inferior teeth. The three lesions containing pus were drained from anterior and posterior brain region and the laboratory evaluation revealed the presence of Streptococcus viridians and Bacteroides. Postoperative period was uneventful with excellent recovery after 1 year of surgery. Final diagnosis was able to be done due to excellent image exams availability like computer tomography and magnetic resonance using diffusion and perfusion techniques. Discussion: The early detection of this pathology with the correct diagnosis essential to give the patient the best treatment including antimicrobial drugs and drainage is of extreme importance. © 2011 Springer-Verlag.

Comparative study of the healing process when using Vicryl®, Vicryl Rapid®, Vicryl Plus®, and Monocryl® sutures in the rat dermal tissue

Introduction: Various types of sutures are available in the market with different constitutions. However, there is a lack of research to assess and quantify the behavior of these materials. Resources and materials: This study comes benchmark wires polyglactin 910 (Vicryl ®), irradiated polyglactin 910 (Vicryl Rapid ®), polyglactin 910 treated with triclosan (Vicryl Plus ®), and poliglecaprone 25 (Monocryl ®). For this, we used 40 rats that were divided into two groups, underwent two skin incisions longitudinal 2-cm long. In Group A, simple interrupted sutures using irradiated polyglactin 910 on the right and left side of polyglactin 910, and in group B, polyglactin 910 with triclosan on the right and the left poliglecaprone 25 were made. At 2, 7, 14, and 28 days after surgery, the ten animals were killed per period, and the samples were processed for histomorphologic and histometric analysis. Conclusions: The results demonstrated that the wire poliglecaprone 25 showed better biological response, with less inflammatory infiltrates and rapid organization of connective tissue. © 2012 Springer-Verlag Berlin Heidelberg.

Prospective study of postoperative sensory disturbances after surgical treatment of mandibular fractures

Introduction: This present study's purpose is to evaluate the degree of paresthesia and recovery of inferior alveolar nerve in patients with mandible fractures who underwent surgical treatment. Material and methods: Nineteen patients were evaluated (27 hemimandibles) at six different times: preoperative (T1), postoperative 1 week (T2), postoperative 1 month (T3), postoperative 3 months (T4), postoperative 6 months (T5), and postoperative 1 year (T6). Subjective and objective methods were used for this evaluation. Results: The results were analyzed using likelihood ratio chi-square test for the hypothesis of no association between indicators of sensitivity and responses to the questionnaire, and the Cochran-Mantel-Haenszel test for equality hypothesis. All objective tests showed a statistically significant worsening in sensitivity at T2 (p < 0. 0001) and a significant improvement after T4 (α < 0. 05). The subjective tests showed an association with the objectives tests, and improvement in sensitivity after T4 (p < 0. 0001) was noted. Discussion: The first postoperative week is the period in which there are major changes with respect to sensitivity, and after 3 months postoperatively, the recovery reaches its apex with little difference observed after this period. In this research 100 % of the patients analyzed recovered all sensibility until T6. © 2012 Springer-Verlag.

Paranasal sinus infection causing orbital subperiosteal abscess: Surgical management of this devastating entity

Background: Orbital infection is an uncommon devastating infection and is usually a complication of paranasal sinus infection. Without appropriate treatment, orbital infection may lead to serious complications, even death. Prompt treatment is mandatory to avoid visual loss or intracranial complications. The literature shows that initially, intravenous antibiotics should be administered, and after 48 h, if no improvement appears, the affected orbit and the sinuses must be surgically drained. The authors describe two cases of orbital cellulitis with a brief literature review. Case report: The authors describe two cases of orbital abscess caused by paranasal sinus infection. In case 1, the patient presented a decreased visual acuity associated with ophthalmoplegia of the right eye. In case 2, the patient presented a decreased visual acuity. Thus, administration of intravenous antibiotic combined with surgical drainage was performed. After surgical procedure, eye movements were normalized in case 1, and in both patients, the visual acuity returned to normal parameters. Discussion: The authors recommend early surgical drainage with parenteral antibiotic administration and careful postoperative observations by monitoring the signs and symptoms of the orbital complaint. © 2012 Springer-Verlag.

Informe bienal (28 abril 1988-11 mayo 1990) = Biennial report (28 April 1988-11 May 1990) = Rapport biennal (28 avril 1988-11 mai 1990)

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Serotonergic neurons in the nucleus raphé obscurus are not involved in the ventilatory and thermoregulatory responses to hypoxia in adult rats

The medullary raphé is an important component of the central respiratory network, playing a key role in CO2 central chemoreception. However, its participation in hypoxic ventilatory responses is less understood. In the present study, we assessed the role of nucleus raphé obscurus (ROb), and specifically 5-HT neurons confined in the ROb, on ventilatory and thermoregulatory responses to hypoxia. Chemical lesions of the ROb were performed using either ibotenic acid (non-specific lesion; control animals received PBS) or anti-SERT-SAP (5-HT specific lesion; control animals received IgG-SAP). Ventilation (VE; whole body plethysmograph) and body temperature (Tb; data loggers) were measured during normoxia (21% O2, N2 balance) and hypoxia exposure (7% O2, N2 balance, 1h) in conscious adult rats. Ibotenic acid or anti-SERT-SAP-induced lesions did not affect baseline values of VE and Tb. Similarly, both lesion procedures did not alter the ventilatory or thermoregulatory responses to hypoxia. Although evidence in the literature suggests a role of the rostral medullary raphé in hypoxic ventilatory responses, under the present experimental conditions our data indicate that caudal medullary raphé (ROb) and its 5-HT neurons neither participate in the tonic maintenance of breathing nor in the ventilatory and thermal responses to hypoxia. © 2013 Elsevier B.V.

Estimates of genetic parameters for carcass, growth and reproductive traits in Nellore cattle

The objective of this study was to estimate genetic parameters for female mature weight (FMW), age at first calving (AFC), weight gain from birth to 120 days (WG_B_120), from 210 to 365 days (WG_210_365), rib eye area (REA), back fat thickness (BF), rump fat (RF) and body weight at scanning date (BWS) using single and multiple-trait animal models by the REML method from Nellore cattle data. The estimates of heritability ranged from 0.163±0.011 for WG_210_365 to 0.309±0.028 for RF using the single-trait model and from 0.163±0.010 for WG_210_365 to 0.382±0.025 for BWS using the multiple-trait model. The estimates of genetic correlations ranged from -0.35±0.08 between AFC with BF to 0.69±0.04 between WG_B_120 with BWS. Selection for weights gains, REA, and BWS can improve FMW. © 2013 Elsevier B.V.