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Under what categories should criticism be made of a literary work that at the same time is a complaint against ethics? This was the problem that provoked so many discussions after the publication of Friedrich Schlegel's novel, Lucinde, which became an important reference of the romantic movement. In this article, Kierkegaard's critique of Lucinde is presented from two perspectives: first, the ironic nature of the novel as a social criticism, especially referring to social customs around love and marriage; second, the reflections of the Danish philosopher on the aesthetic personality of Julius, the main protagonist of the novel, to address the existential identity that Schlegel gives him throughout the work. [ABSTRACT FROM AUTHOR]

Background. Cephalea is one of the leading causes of medical consultation in the world, with over 90% prevalence, making accurate identification through detailed clinical history and physical examination essential. Only a minority of patients with cephalea can be expected to develop a significant illness. Neuroimaging studies such as cranial computed tomography are recommended in patients in whom doctors seek to rule out a secondary cause of cephalea, in cases with atypical, irst time cephalea or exacerbation of existing cephalea, and when abnormalities are detected by physical examination, among others. Notwithstanding, some investigators suggest that neuroimaging studies rarely contribute to the diagnosis of this condition. purpose. Show the usefulness of cranial computed tomography, in simple and contrasted phase, in the search for structural anomalies in patients with cephalea without associated neurological alteration at Hospital General de Mexico. Material and methods. The interpretations of cranial computed tomographies, in simple and contrasted phase, taken in patients with diagnosis of cephalea under study sent to the Hospital General de Mexico Radiology and Image Service without distinction of age or gender, without the presence of neurological alterations and without antecedents of cranial surgery, were analyzed in the period from August 1, 2010, through June 30, 2011. results. Eighty-one cranial computed tomographies in simple and contrasted phase were taken. Most of the patients were female (53 women, 65.5%) and the majority of cases were in the age range of 20 to 39 years. The most common report was absence of lesions (46 cases, 56.7%) followed by loss of cerebral volume (17.7%) and calcified granulomas of probable parasitic origin (8.6%). Other interesting findings include a case with aneurism of the middle cerebral artery and studies in which only sinusitis was observed. discussion. In recent years there has been an increase in the use of computed tomography in diagnosis of cephalea. Most of the patients with cephalea studied had no clinically signiicant indings in this image study; the most frequently reported include calciied granulomas of probable parasitic origin, indications of endocranial hypertension (as well as a case of aneurism of the middle cerebral artery and another with communicating hydrocephalus found in this investigation). Our results are similar to those reported by other authors. On the other hand, we did not observe that administration of endovenous contrast medium provided additional information to that obtained in the simple phase. Conclusions. Cranial computed tomography is part of the study protocol in patients with cephalea due to its greater accessibility and low cost; its main usefulness lies in ruling out the presence of structural alterations as secondary causes of head ache. [ABSTRACT FROM AUTHOR]

Ischemic stroke is the third cause of death and the first cause of disability in industrialized countries. It is caused by a stop in the blood supply (and the resulting interruption in oxygen supply, mainly) to a region of the brain. This produces, ultimately, tissue necrosis with cytotoxic edema of the encephalon. Diagnosing an ischemic stroke requires physical examination and clinical studies such as computed tomography (CT) and magnetic resonance (MR). CT is a method that helps to identify the early tomographic signs of ischemia. The purpose of this study is to determine the incidence of ischemic stroke and identify tomographic changes over the first 24 hours after such events, all in patients at Hospital General de Mexico. Material and methods. A longitudinal, retrospective study was conducted, which included female and male patients between 25 and 105 years of age, with suspected ischemic stroke referred to the Hospital General de Mexico Radiology and Image Unit's Computed Tomography Department in the period from January 1 through June 30, 2011. results. In the period considered, a total of 386 patients were studied, of whom 80 were between 55 and 65 years of age and predominantly female. Of the total patients with ischemic stroke, 85 presented poor differentiation of gray and white matter. The site of greatest damage was the left parietal lobe (60 patients). discussion. Ischemic stroke is known to be the second cause of hospital death, predominant in males, and the risk factor is doubled from 55 years of age. It is a vital condition with a twilight period of up to 6 hours in which there is brain tissue that has not yet suffered infarction and is potentially recoverable by means of thrombolysis, which supports the saying: "time is brain". Conclusion. The technology to identify acute ischemic stroke has advanced in the last twenty years and computed tomography is an example of that. Hospital General de Mexico does not implement a tomographic protocol like in other developed countries due to the high demand for studies and the limited resources available to perform them. However, it is possible to offer adequate treatment for the affected population. [ABSTRACT FROM AUTHOR]

A new synthesis method for Sb−V−O based catalysts is proposed. VSbO 4phase is supported both in alumina and in niobia because it is known that such structure is the active phase for acrylonitrile formation. The relevance of the support on the structure and performance of the VSbO 4phase is evaluated by X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy and in the ammoxidation of propane to acrylonitrile. The role of segregated antimony oxide for the VSbO 4phase is confirmed in VSbO 4/Al 2O 3. In this system, segregated antimony oxide is critical for the redox cycle of vanadium sites. However, a new catalytic phase forms in VSbO 4/Nb 2O 5. Niobia support affords an efficient phase other than VSbO 4that is selective to acrylonitrile formation. This phase appears to be a Sb-promoted V−Nb−O one. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the potential for intensity-modulated radiotherapy (IMRT) to spare the bowel in rectal tumors. Methods and Materials: The targets (pelvic nodal and rectal volumes), bowel, and bladder were outlined in 5 patients. All had conventional, three-dimensional conformal RT and forward-planned multisegment three-field IMRT plans compared with inverse-planned simultaneous integrated boost nine-field equally spaced IMRT plans. Equally spaced seven-field and five-field and five-field, customized, segmented IMRT plans were also evaluated. Results: Ninety-five percent of the prescribed dose covered at least 95% of both planning target volumes using all but the conventional plan (mean primary and pelvic planning target volume receiving 95% of the prescribed dose was 32.8 ± 13.7 Gy and 23.7 ± 4.87 Gy, respectively), reflecting a significant lack of coverage. The three-field forward planned IMRT plans reduced the volume of bowel irradiated to 45 Gy and 50 Gy by 26% ± 16% and 42% ± 27% compared with three-dimensional conformal RT. Additional reductions to 69 ± 51 cm3 to 45 Gy and 20 ± 21 cm3 to 50 Gy were obtained with the nine-field equally spaced IMRT plans—64% ± 11% and 64% ± 20% reductions compared with three-dimensional conformal RT. Reducing the number of beams and customizing the angles for the five-field equally spaced IMRT plan did not significantly reduce bowel sparing. Conclusion: The bowel volume irradiated to 45 Gy and 50 Gy was significantly reduced with IMRT, which could potentially lead to less bowel toxicity. Reducing the number of beams did not reduce bowel sparing and the five-field customized segmented IMRT plan is a reasonable technique to be tested in clinical trials. [Copyright &y& Elsevier]

Solvent-free microwave-activation, in the liquid phase using an alumina supported V-Sb-O catalyst, affords highly efficient conversion (47%) of glycerol into acrylonitrile under mild conditions, short reaction times and in the absence of any solvent; in addition, it increases selectivity (>80%) compared to conventional thermal activation. [ABSTRACT FROM AUTHOR]

Nova shells can provide important information on their distance, their interactions with circumstellar and interstellar media, and the evolution in morphology of the ejecta. We have obtained narrowband images of a sample of five nova shells, namely DQ Her, FH Ser, T Aur, V476 Cyg, and V533 Her, with ages ranging from 50 to 130 yr. These images have been compared with suitable available archival images to derive their angular expansion rates. We find that all the nova shells in our sample are still in the free expansion phase, which can be expected, as the mass of the ejecta is 7–45 times larger than the mass of the swept-up circumstellar medium. The nova shells will keep expanding freely for time periods up to a few hundred years, reducing their time dispersal into the interstellar medium. [ABSTRACT FROM AUTHOR]

We have recently confirmed the planetary nebula (PN) nature of PM 1–242, PM 1–318 and PM 1–322. Here we present high-resolution long-slit spectra of these three PNe in order to analyze their internal kinematics and to investigate their physical structure. PM 1–242 is a tilted ring and not an elliptical PN as suggested by direct images. The object is probably related to ring-like PNe and shows an unusual point-symmetric brightness distribution in the ring. PM 1–318 is a pole-on elliptical PN, instead of a circular one as suggested by direct images. PM 1–322 is spatially unresolved and its spectrum shows large differences between the forbidden lines and Hαprofiles, with the latter showing a double-peaked profile and relatively extended wings (FWZI ∼325 km s-1). These properties are found in other PNe that are suspected to host a symbiotic central star. [ABSTRACT FROM AUTHOR]

Planetary nebulae (PNe) can be roughly categorized into several broad morphological classes. The high quality images of PNe acquired in recent years, however, have revealed a wealth of fine structures that preclude simplistic models for their formation. Here we present narrow-band, sub-arcsecond images of a sample of relatively large PNe that illustrate the complexity and variety of small-scale structures. This is especially true for bipolar PNe, for which the images reveal multi-polar ejections and, in some cases, suggest turbulent gas motions. Our images also reveal the presence or signs of jet-like outflows in several objects in which this kind of component has not been previously reported. [ABSTRACT FROM AUTHOR]

Abstract: Background and purpose: Intensity modulated radiotherapy (IMRT) at the Royal Marsden Hospital London was introduced in July 2001. Treatment delivery was dynamic using a single-phase technique. Concerns were raised regarding increased clinical workload due to introduction of new technology. The potential increased use of resources was assessed. Patients and methods: IMRT patient selection was within guidelines of clinical trials and included patients undergoing prostate plus pelvic lymph node (PPN) irradiation and head and neck cancer (HNC) treatment. Patient planning, quality assurance and treatment times were collected for an initial IMRT patient group. A comparative group of patients with advanced HNC undergoing two- or three-phase conventional radiotherapy, requiring matched photon and electron fields, were also timed. Results: The median overall total planning time for IMRT was greater for HNC patients compared to the PPN cohort. For HNC the overall IMRT planning time was significantly longer than for conventional. The median treatment time for conventional two- or three-phase HNC treatments, encompassing similar volumes to those treated with IMRT, was greater than that for the IMRT HNC patient cohort. A reduction in radiographer man hours per patient of 4.8h was recorded whereas physics time was increased by 4.9h per patient. Conclusions: IMRT currently increases overall planning time. Additional clinician input is required for target volume localisation. Physics time is increased, a significant component of this being patient specific QA. Radiographer time is decreased. For HNC a single phase IMRT treatment has proven to be more efficient than a multiple phase conventional treatment. IMRT has been integrated smoothly and efficiently into the existing treatment working day. This preliminary study suggests that IMRT could be a routine treatment with efficient use of current radiotherapy resources. [Copyright &y& Elsevier]

The Wolf–Rayet (WR) nebula NGC 3199 has been suggested to be a bow shock around its central star, WR 18, which is presumably a runaway star, because optical images of the nebula show a dominating arc of emission southwest of the star. We present the XMM-Newton detection of extended X-ray emission from NGC 3199, unveiling the powerful effect of the fast wind from WR 18. The X-ray emission is brighter in the region southeast of the star and an analysis of the spectral properties of the X-ray emission reveals abundance variations: (i) regions close to the optical arc present nitrogen-rich gas enhanced by the stellar wind from WR 18 and (ii) gas at the eastern region exhibits abundances close to those reported for the nebular abundances derived from optical studies, which is a signature of an efficient mixing of the nebular material with the stellar wind. The dominant plasma temperature and electron density are estimated to be T ≈ 1.2 × 106 K and ne = 0.3 cm−3 with an X-ray luminosity in the 0.3–3.0 keV energy range of LX = 2.6 × 1034 erg s−1. Combined with information derived from Herschel and the recent Gaia first data release, we conclude that WR 18 is not a runaway star and that the formation, chemical variations, and the shape of NGC 3199 depend on the initial configuration of the interstellar medium. [ABSTRACT FROM AUTHOR]

Non-thermal radiation has been predicted within bow shocks around runaway stars by recent theoretical works. We present X-ray observations toward the runaway stars ζ Oph by Chandra and Suzaku and of BD+43°3654 by XMM-Newton to search for the presence of non-thermal X-ray emission. We found no evidence of non-thermal emission spatially coincident with the bow shocks; nonetheless, diffuse emission was detected in the vicinity of ζ Oph. After a careful analysis of its spectral characteristics, we conclude that this emission has a thermal nature with a plasma temperature of T ≈ 2 × 106 K. The cometary shape of this emission seems to be in line with recent predictions of radiation-hydrodynamic models of runaway stars. The case of BD+43°3654 is puzzling, as non-thermal emission has been reported in a previous work for this source. [ABSTRACT FROM AUTHOR]