89 resultados para Immediate temporization


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The results of ecological restoration techniques can be monitored through biological indicators of soil quality such as the leaf litter arthropod fauna. This study aimed to determine the immediate effect of brushwood transposition transferred from an area of native vegetation to a disturbed area, on the leaf litter arthropod fauna in a degraded cerrado area. The arthropod fauna of four areas was compared: a degraded area with signal grass, two experimental brushwood transposition areas, with and without castor oil plants, and an area of native cerrado. In total, 7,660 individuals belonging to 23 taxa were sampled. Acari and Collembola were the most abundant taxa in all studied areas, followed by Coleoptera, Diptera, Hemiptera, Hymenoptera, and Symphyla. The brushwood transposition area without castor oil plants had the lowest abundance and dominance and the highest diversity of all areas, providing evidence of changes in the soil community. Conversely, the results showed that the presence of castor oil plants hampered early succession, negatively affecting ecological restoration in this area.

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In the last years, several research groups have been working on the synthesis of new steroidal plant hormones called brassinosteroids (BS), which promote plant growth and better crops. Many synthetic targets and applications of these compounds and their analogues have been described in the literature. From Solanum species of the Distrito Federal, we isolated the steroidal alkaloid solasodine, which was then converted into our starting material, vespertiline. By functionalization of rings A and B, we have synthesized a new analogue of BS, with a 2alpha,3alpha-dihydroxy-6-one structure, typical of the naturally occurring BS castasterone, the immediate biosynthetic precursor of brassinolide.

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A new approach for teaching in basic experimental organic chemistry is presented. Experimental work goes on parallel to theoretical lectures leading to an immediate application of theoretical concepts transmitted therein. One day/week is dedicated exclusively to the organic laboratory. Reactions are proposed as problems to be solved; the student has to deduce the structure of the product on the basis of his observations, the analytical data and his mechanistical knowledge. 70 different experiments, divided in 7 thematical chapters, are presented. All experiments require the analysis and discussion of 1H and 13C NMR, IR and UV spectra. Additional questions about each reaction have to be answered by the student in his written report. Laboratory safety is garanteed by the exclusion or substitution of hazardous and toxic reagents. Microscale preparations are adopted in most cases to lower the cost of materials and the amount of waste. Recycling of many reaction products as starting materials in other experiments reduces the need for commercial reagents and allows the execution of longer reaction sequences. Only unexpensive standard laboratory equipment and simple glassware are required. All experiments include instructions for the save treatment or disposal of chemical waste.

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The problem of convenient access to quantitative Hückel-level descriptions of Möbius and Hückel annulenes for undergraduate lectures about aromaticity is discussed. Frost circle, Zimmerman circle, double circle and Langler semicircular mnemonics are described. The relationship between spectra (complete sets of secular equation roots) for an isoconjugate pair of Hückel and Möbius annulenes and the corresponding acyclic polyene with one less carbon is fully developed. In addition to providing an alternative path to exact spectrum roots, this relationship provides immediate access to almost half of the eigenfunctions for an isoconjugate annulene pair. The remaining eigenfunctions may be obtained very easily.

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Malaria is still one of the major diseases in the world, causing physical and economic problems in tropical regions. Artemisinin (Qinghaosu), a natural compound identified in Artemisia annua L. , is an effective drug mainly against cerebral malaria. The action of this drug is immediate and parasitaemia in the treatment of drug-resistant malaria is rapidily reduced, justifying the industrial production of artemisinin. This article focuses on the industrial production of this potent antimalarial drug, including strategies for enhancing yield using inexpensive and easy steps.

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The preparation of enantiomerically pure or enriched substances is of fundamental importance to pharmaceutical, food, agrochemical, and cosmetics industries and involves a growing market of hundreds of billions of dollars. However, most chemical processes used for their production are not environmentally friendly because in most cases, stoichiometric amounts of chiral inductors are used and substantial waste is produced. In this context, asymmetric catalysis has emerged as an efficient tool for the synthesis of enantiomerically enriched compounds using chiral catalysts. More specifically, considering the current scenario in the Brazilian chemical industry, especially that of pharmaceuticals, the immediate prospect for the use of synthetic routes developed in Brazil in an enantioselective fashion or even the discovery of new drugs is practically null. Currently, the industrial production of drugs in Brazil is primarily focused on the production of generic drugs and is basically supported by imports of intermediates from China and India. In order to change this panorama and move forward toward the gradual incorporation of genuinely Brazilian synthetic routes, strong incentive policies, especially those related to continuous funding, will be needed. These incentives could be a breakthrough once we establish several research groups working in the area of organic synthesis and on the development and application of chiral organocatalysts and ligands in asymmetric catalysis, thus contributing to boost the development of the Brazilian chemical industry. Considering these circumstances, Brazil can benefit from this opportunity because we have a wide biodiversity and a large pool of natural resources that can be used as starting materials for the production of new chiral catalysts and are creating competence in asymmetric catalysis and related areas. This may decisively contribute to the growth of chemistry in our country.

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The article discusses how Nietzsche understands the institution of law and morals in distinction to Kant and the Christian tradition. It argues that Nietzsche to a large extent is inspired by the paradigm-shift toward a evolutionary biological thinking introduced by several of his peers in the late 19th century, among else F. A. Lange, who sees this shift as a sobering scientific-materialistic alternative to Kant. In Nietzsche, the Kantian moral imperative is replaced with a notion of a morality emerging thanks to historical, or pre-historical, civilizational processes, imposed on a feebleminded human without any inherent rational dispositions to obey Law. It is also a process, which rather than universalizing the human, splits it in a duality where one part obeys old immediate self-interests and another part obeys new 'commands,' having been shouted 'into the ear' by a so-called 'commander.' The compliance with law takes two radically different forms in Nietzsche: servile and mediocre individuals need to be exposed to discipline and punishment in order to adopt Law; while so-called 'sovereign' individuals are able to impose law upon themselves. The figure of the 'sovereign' has consequently been an issue for vigorous debate in especially the Anglo-Saxon tradition of Nietzsche research, since his apparent 'respect for law' and 'sense of duty' reiterate typical Kantian qualities. Relating to these discussions, I suggest that Nietzsche's 'sovereign' (in one context) is identical his 'commander' (in other contexts). When the 'sovereign' as such imposes law upon himself and others, his act is conventional and arbitrary (like language in Saussure), and is rather irrational than rational as in Kant. His will is not a good will, nor a rational will with a vision of human autonomy. His command of himself and others is a performative, thus without truth-value (like illocutionary speech-acts in Austin and Searle).

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The proper management of agricultural crop residues could produce benefits in a warmer, more drought-prone world. Field experiments were conducted in sugarcane production areas in the Southern Brazil to assess the influence of crop residues on the soil surface in short-term CO2 emissions. The study was carried out over a period of 50 days after establishing 6 plots with and without crop residues applied to the soil surface. The effects of sugarcane residues on CO2 emissions were immediate; the emissions from residue-covered plots with equivalent densities of 3 (D50) and 6 (D100) t ha-1 (dry mass) were less than those from non-covered plots (D0). Additionally, the covered fields had lower soil temperatures and higher soil moisture for most of the studied days, especially during the periods of drought. Total emissions were as high as 553.62 ± 47.20 g CO2 m-2, and as low as 384.69 ± 31.69 g CO2 m-2 in non-covered (D0) and covered plot with an equivalent density of 3 t ha-1 (D50), respectively. Our results indicate a significant reduction in CO2 emissions, indicating conservation of soil carbon over the short-term period following the application of sugarcane residues to the soil surface.

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Diaphragmatic hernia secondary to blunt or penetrating trauma is rarely by itself a fatal event. However, if unpercieved, it may lead to severe complications caused by herniation of abdominal contents to the ethorax. Blunt trauma related to car accidents is the most frequent cause of diaphragmatic hernias. Associated injuries are frequently observed, provoked by severe traumas of great impact. These blunt trauma hernias occur mainly on the left side due to abdominal anatomy, since the liver is usually located on the right side. When injuries are observed on the right they tend to be more severe, generally related to major trauma of solid organs. Less frequently diaphragmatic hernias may be bilateral. The management of diaphragmatic injury would appear to be a simple matter of suturing the defect. However, peroperative diagnosis can be difficult and even at the time of surgery some diaphragmatic injuries can be overlooked if carefull exploration is not done. Associated injuries tend to divert attention from the diaphragmatic injury. Laparoscopic diagnosis and repair have been described with successfull. Laparotomy or thoracotomy can be employed for surgical repair of traumatic diaphragmatic hernias. Standard (laboratory/imaging) examinations may fail to make the diagnosis. Recently, the laparoscopic approach has proved useful for more precise evaluation of such injuries, very often allowing immediate repair of these lesions.

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Traumatic diaphragmatic hernia is defined as a laceration of the diaphragm with an abdominal viscera herniation into the thorax. It is usually asymptomatic, with the exception of the cases with obstruction, strangulation, necrosis or perforation of the herniaded viscera. It is classified as acute, latent or chronic, in accordance with the evolutive period. At the latent phase, symptoms are indefinite and the radiological signals, which are suggestive of thoracic affections, are frequent and can induce a diagnosis error, leading to inadequate treatment.This article presents a case of chronic traumatic diaphragmatic hernia which was complicated by a gastricpleuralcutaneous fistula, due to an inadequate thoracic drainage. Considering that this is a chronic affection with an unquestionable surgical indication, due to the complications risk, it is essential to have a detailed diagnostic investigation, which aims at both avoiding an intempestive or inadequate therapeutics behaviour and reducing the affection morbimortality. Recently, the videolaparoscopic approach has proved to be more precise when compared to the other diagnostic methods, by direct visualization of the diaphragmatic laceration, allowing its correction by an immediate suture.

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Videolaparoscopic surgery has been used for treatment of almost all surgical abdominal diseases, mainly where there are no large ressections, or operative field is limited. In these situations, laparoscopic surgery has the advantages of less morbidity, quick recovery and good cosmetic results. Bezoars removal, or its mobilization, is probably included in these possible proceedings. Three non-laparotomic procedures were described: 1. endoscopic-laparoscopic; 2. videolaparoscopy and mobilization of intestinal bezoar to the cecum; 3. laparoscopy and gastrotomy for bezoar removal, through suprapubic incision or the umbilical punction. There have been only two publications describing the videolaparoscopic method for bezoar removal, and the methods applied can be complications or morbidity related. We describe one case where the applied technique is simple and easy to perform, time saving and probably less complications-related. This technique, with four trocars, utilized a plastic bag besides the stomach to be opened, followed by gastrotomy, bezoar removal and immediate introduction in the plastic bag, suture of gastrotomy and removal through the left subcostal trocar. This technique was feasible and easy to perform, with short operative time, and there were no intra or post-operative complications; the patient was discharged in the second post-operative day, and is without further problems after one year follow-up. We believe that this could be an adequate technique to perform laparoscopic gastric bezoar removal, and the rigid sequence of operative events allows a quick procedure, with minimal contamination. The videolaparoscopy seems to be an adequate access to surgical treatment of gastro-intestinal bezoars, with or without obstruction, and should be the ellected the procedure of choice to begin the surgical treatment, with convertion to laparotomy in case of any intra-operative adversity.

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Abdominal aorta wounds carries a high immediate mortality. Few patients reach hospital care alive. There are no reports on Medline (1969-2002) about aortic wounds of foreign body with retention. A case with upper abdominal aortic wound with an inlaid blade is reported. The retained blade fixed the stomach to the surgical field, difficulting the vascular control, leading to an unconventional approach and allowing extensive contamination. The patient developed multiple organ dysfunction and died at fifth postoperative day. Singularities of an inlaid knife in upper abdominal aorta and changes in traditional approach are discussed. The authors assumed that the inlaid knife decreased the bleeding, allowing the patient arrival to the hospital, but worsened the approach to the aorta wound.

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Appendices epiploicae can be the site of torsion and appendagitis. Diagnosis is currently being made by ultrasonography and computerized tomography. Expectant treatment is proposed based on the assumption that epiploic appendicitis is a self limited affection. A case of torsion of a sigmoid epiploic appendage is described. The condition was missed by abdominal ultrasonography. Correct diagnosis and immediate definite treatment were performed by videolaparoscopy.

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The practice of auto-transfusion is highly considered due to its safety and economic beneficts. It comprises two basic modalities: "Reinfusion" and "Pre-Collection" of blood. The reinfusion uses the patient's own blood spurted either from the patient's previous hemorrhage or during the surgery. The auto-transfusion of Pre-Collect uses the patient's blood tajen before surgery and it consists two basic modalities: The multiple Pre-Collection in which the blood is taken from the patient much before the scheduled sate of the surgery and the Pre-Collection done 10-30 minutes before surgery, which we presently designated as "Immediate Pre-Collection" (or Pre-Deposit for Immediate Utilization) which constitutes the basic topic of this essay.