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In the latest literature, climate models show that the conditions for pines, spruces, larches, and birches will deteriorate significantly. In Poland, as well as in other European countries, there are already signs of the decline of these species. This review article deals with the symbiotic relationships between fungi and plants, which can hardly be overestimated, using the example of pine trees. These are the oldest known symbiotic relationships, which are of great benefit to both components and can help plants, in particular, survive periods of severe drought and the attack of pathogens on the roots. This article describes symbioses and their causal conditions, as well as the mycorrhizal components of pine trees and their properties; characterizes ectomycorrhizal fungi and their mushroom-forming properties; and provides examples of the cultivation of pure fungal cultures, with particular attention to the specificity of the mycorrhizal structure and its effects on the growth and development of Pinus species. Finally, the role of mycorrhiza in plant protection and pathogen control is described.
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Uranium and plutonium isotope concentrations as well as 236U/238U and 240Pu/239Pu atom ratios were measured by AMS in human lung samples from the early 1960s. The 236U concentrations as well as the 236U/238U atom ratios show a maximum in 1964, 239Pu and 240Pu concentrations are increasing continually from 1962 to 1965. 236U/238U atom ratios are lower by two orders of magnitude compared to corresponding aerosol data from Vienna, probably due to older 238U deposited in the lungs, enhanced 238U concentrations in the city air, and activity partition within different particle sizes. The 236U/239Pu atom ratios in lung samples are also lower than expected from the aerosol data, while 240Pu/239Pu atom ratios lie well within the range typical for nuclear bomb fallout.
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Plutônio , Monitoramento de Radiação , Cinza Radioativa , Áustria , Humanos , Pulmão/química , Plutônio/análise , Cinza Radioativa/análise , Estudos RetrospectivosRESUMO
Global change has resulted in chronic shifts in fire regimes. Variability in the sensitivity of tree communities to multi-decadal changes in fire regimes is critical to anticipating shifts in ecosystem structure and function, yet remains poorly understood. Here, we address the overall effects of fire on tree communities and the factors controlling their sensitivity in 29 sites that experienced multi-decadal alterations in fire frequencies in savanna and forest ecosystems across tropical and temperate regions. Fire had a strong overall effect on tree communities, with an average fire frequency (one fire every three years) reducing stem density by 48% and basal area by 53% after 50 years, relative to unburned plots. The largest changes occurred in savanna ecosystems and in sites with strong wet seasons or strong dry seasons, pointing to fire characteristics and species composition as important. Analyses of functional traits highlighted the impact of fire-driven changes in soil nutrients because frequent burning favoured trees with low biomass nitrogen and phosphorus content, and with more efficient nitrogen acquisition through ectomycorrhizal symbioses. Taken together, the response of trees to altered fire frequencies depends both on climatic and vegetation determinants of fire behaviour and tree growth, and the coupling between fire-driven nutrient losses and plant traits.
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Incêndios , Árvores , Ecossistema , Florestas , SoloRESUMO
Introducción: La adrenoleucodistrofia ligada al X es una enfermedad peroxisomal causada por un defecto en el gen ABCD1, el cual ocasiona acumulación en el suero, la corteza adrenal y la sustancia blanca del sistema nerviosos central, de ácidos grasos saturados de cadena larga. La clínica se caracteriza por deterioro neurológico e insuficiencia adrenal. Objetivo: Presentar los hallazgos clínicos, bioquímicos y radiológicos de ocho pacientes con esta afección. Material y métodos: Entre 25 pacientes atendidos en el Instituto de errores Innatos del Metabolismo entre 200-2004; se identificaron mediante valoración neuropediátrica, resonancia magnética cerebral y estudios bioquímicos de arilsultafatasa y hexosaminidasa, ocho casos de adrenoleucodistrofia ligada al X. En todos los casos se realizó determinación de niveles de ácidos graso de cadena larga mediante cromatografía de gases y en algunos con espectroscopia de masa. Resultados: El rango de edad fue 5-26 años, la clínica heterogéna, incluso con un paciente asintomático. Dos pacientes presentaron disfunción adrenal y uno adrenoleucodistrofia. Conclusiones: Este defecto metabólico es de baja prevalencia, clínica diversa y evolución variable. Los estudios metabólicos facilitan la confirmación de los casos y la identificación de los portadores
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AdrenoleucodistrofiaRESUMO
Survival analysis methodologies provide novel approaches for forest mortality analysis that may aid in detecting, monitoring, and mitigating of large-scale forest health issues. This study examined survivor analysis for evaluating a regional forest health issue - Missouri oak decline. With a statewide Missouri forest inventory, log-rank tests of the effects of covariates on the survivor function and equality of the survivor function among classes were conducted for selected oak species. Additionally, hazard functions were determined for diameter classes for damaged and undamaged oaks. Results indicate that mortality appears to vary significantly among some inventory classes such as oak species, but not among other classes such as ownership class. Indicators of individual tree vigor (i.e., crown class and ratio) were more significant predictors of oak tree mortality than site/stand attributes (i.e., density and aspect). Finally, results indicate that even fast-growing oak trees are at high risk of mortality if damaged by disease. Survival analyses, such as those applied in this study, may enable testing of forest health hypotheses using large-scale inventories. In the context of Missouri's oak forest decline, study results suggest management efforts should focus on limiting the spread of disease damage, increasing the vigor of residual trees, and emphasizing small trees when developing stand prescriptions.
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Conservação dos Recursos Naturais , Agricultura Florestal/estatística & dados numéricos , Quercus , Agricultura Florestal/métodos , Missouri , Análise de SobrevidaRESUMO
Many guideline only implicitly or vaguely define the process of health care delivery. However, an explicit model of the medical tasks comprising this process is needed before active decision support at the patient encounter can take place. We propose to use a structured, but semi-formal representation as intermediate step in the process of enacting a guideline. This allows for the application independent representation of the content of a guideline enabled for decision support. The process and the tools of the methodology have been applied to enable guidelines from the field of Diabetes mellitus.
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Tomada de Decisões Assistida por Computador , Sistemas de Apoio a Decisões Clínicas , Guias de Prática Clínica como Assunto , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/terapia , Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/terapia , Humanos , Design de SoftwareRESUMO
[reaction: see text]. An efficient method for the generation of silyl vinylketenes from the thermal reaction of Fischer carbene complexes with silyl-substituted phenylacetylenes is described. Although the silyl vinylketene products are highly stable, conditions have been identified to induce a benzannulation/silyl migration process, providing aromatic silyl ethers.
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BACKGROUND: Alterations in mental status are common among patients in the cardiothoracic surgical intensive care unit. Changes in mental status can be caused by metabolic factors, medications, or brain injury. In this setting, reliable, serial neurological evaluations are critical for assessing the effectiveness of treatment and the need for additional studies. OBJECTIVES: To estimate the reliability of the Rancho Los Amigos Cognitive Scale and the newly developed Neurologic Intensive Care Evaluation as measures of cognitive function in the cardiothoracic surgical intensive care unit. METHODS: Nurses used 1 of the 2 scales as part of routine neurological assessments of patients in the cardiothoracic surgical intensive care unit. For each test, scores of different observers were correlated and a reliability estimate formed. RESULTS: Interrater reliability was high for both evaluations (Rancho scale, 0.91; Neurologic Intensive Care Evaluation, 0.94). Correlations between the scores of different pairs of observers were also high (mean rho values, 0.84 for the Rancho scale and 0.77 for the Neurologic Intensive Care Evaluation). CONCLUSIONS: Both scales are reliable indicators of the neurological state of patients in the cardiothoracic surgical intensive care unit. These scales measure different, although limited, aspects of cognitive function. Each test was simple to administer and did not take more time than the standard nursing neurological examination. Most of the variability in scoring was related to the different degrees of stimulation used by examiners when assessing patients, not to differences in the interpretation of patients' responses.
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Cognição , Unidades de Cuidados Coronarianos/normas , Entrevista Psiquiátrica Padronizada/normas , Exame Neurológico/normas , Pacientes/psicologia , Árvores de Decisões , Humanos , Variações Dependentes do Observador , Estudos Prospectivos , Reprodutibilidade dos Testes , Projetos de Pesquisa , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Besides antibiotics, additionally effective acid inhibition is necessary for the eradication of Helicobacter pylori. OBJECTIVE: To assess the significance of acid suppression and, in particular, treatment with proton pump inhibitors (PPIs) compared with H2 receptor antagonists (H2 RAs). The primary target parameter for the study was H. pylori eradication. In addition, the ulcer healing rate, speed of pain reduction, score for gastritis in the antrum and gastric body, and rate of side effects were recorded. DESIGN: Randomized, double-blinded, multicentre study. PARTICIPANTS: A total of 456 patients between the ages of 18 and 80 years with H. pylori-positive duodenal ulcers were included in the study. METHODS: Using a randomization list, patients were assigned either to a treatment group receiving omeprazole 40 mg once daily, amoxycillin 750 mg three times a day, and metronidazole 500 mg three times a day (OAM), or to a group receiving ranitidine 300 mg once daily, amoxycillin 750 mg three times a day, and metronidazole 500 mg three times a day (RAM). The treatment period was 7 days in both groups. Long-term acid-suppressant treatment was not given. RESULTS: The eradication rate was 87.1% (169/194, intention to treat [ITT]) in the OAM group and 77% (137/ 178, ITT) in the RAM group. The difference of 10.1% (95% CI 2.5-18%) is statistically significant (P= 0.0104). The ulcer healing rate was 93.3% in the OAM group (181/194, ITT) and 92.1% in the RAM group (164/178, ITT, NS). With regard to the speed and intensity of pain reduction, the OAM group was superior to the RAM group. In patients in whom H. pylori eradication was successful, the reduction in the antral and gastric body gastritis score was significantly greater than in patients without eradication. In the OAM group, 39.1% of the patients (n = 90) reported one or more side effects, compared with 44.7% (n = 101) in the RAM group (P= 1.5449, NS). CONCLUSION: Omeprazole (40 mg once daily in the morning) is significantly more effective than ranitidine (300 mg once daily in the morning) with respect to H. pylori eradication when used together with amoxycillin (750 mg three times a day) and metronidazole (500 mg three times a day) for a 7-day treatment period.
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Amoxicilina/administração & dosagem , Úlcera Duodenal/tratamento farmacológico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Metronidazol/administração & dosagem , Omeprazol/administração & dosagem , Ranitidina/administração & dosagem , Adolescente , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada , Úlcera Duodenal/microbiologia , Feminino , Seguimentos , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
A healthcare record should ideally be a repository of data, describing a person's health and how it is being supported; and not, as it is now, describing a person's diseases and treatment only. The healthcare record is the basis for monitoring and decisions. Therefore it should be open and available to all authorized health professionals and to the patient. To make this easier is one of the major advantages of electronic healthcare records (EHCR). The computer-based patient record could make major contributions to improving the healthcare system. This is the motivation to initiatives, projects and routine implementations of electronic patient records. The European Union and national initiatives have put major efforts into the support of this main field of medical information processing.
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PURPOSE: To compare the permeation characteristics of amide bond-containing HIV-1 protease inhibitors and their pyrrolinone-containing counterparts across Caco-2 cell monolayers, a model of the intestinal mucosa. METHODS: Transepithelial transport and cellular uptake of three pairs of amide bond-containing and pyrrolinone-based peptidomimetics were assessed in the presence and absence of cyclosporin A using the Caco-2 cell culture model. The potential of the peptidomimetics to interact with biological membranes was estimated by IAM chromatography. RESULTS: In the absence of cyclosporin A, apical (AP) to basolateral (BL) flux of all compounds studied was less than the flux determined in the opposite direction (i.e., BL-to-AP). The ratio of the apparent permeability coefficients (Papp) calculated for the BL-to-AP and AP-to-BL transport (P(BL-->AP)/P(AP-->BL)) varied between 1.7 and 36.2. When individual pairs were ompared, P(BL-->AP)/P(AP-BL) ratios of the pyrrolinone-containing compounds were 1.5 to 11.5 times greater than those determined for the amide bond-containing analogs. Addition of 25 microM cyclosporin A to the transport buffer reduced the P(BL-->AP)/P(AP-->BL) ratios for all protease inhibitors to a value close to unity. Under these conditions, the amide bond-containing peptidomimetics were at least 1.6 to 2.8 times more able to permeate Caco-2 cell monolayers than were the pyrrolinone-containing compounds. The intrinsic uptake characteristics into Caco-2 cells determined in the presence of 25 microM cyclosporin A were slightly greater for the amide bond-containing protease inhibitors than for the pyrrolinone-containing analogs. These uptake results are consistent with the transepithelial transport results determined across this in vitro model of the intestinal mucosa. CONCLUSIONS: The amide bond-containing and pyrrolinone-based peptidomimetics are substrates for apically polarized efflux systems present in Caco-2 cell monolayers. The intrinsic permeabilities of the amide bond-containing protease inhibitors are slightly greater than the intrinsic permeabilities of the pyrrolinone-based analogs through Caco-2 cell monolayers.
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Células CACO-2/metabolismo , Inibidores da Protease de HIV/farmacocinética , Mimetismo Molecular , Peptídeos/farmacocinética , Transporte Biológico , Células CACO-2/fisiologia , Permeabilidade da Membrana Celular , Cromatografia Líquida de Alta Pressão , Inibidores da Protease de HIV/química , Humanos , Peptídeos/químicaRESUMO
The susceptibility of 40 erythromycin-resistant isolates of Streptococcus pyogenes and 40 multiply-resistant isolates of Streptococcus pneumoniae to six macrolide antibiotics, representing 14-, 15- and 16-membered lactone ring structures, was tested. The genetic basis for macrolide resistance in the strains was also determined. Both erm and mef determinants were encountered in the 36 S. pneumoniae isolates tested, but only mef in the five S. pyogenes isolates tested. All isolates showed cross-resistance among the 14-membered macrolides erythromycin, clarithromycin and roxithromycin and the 15-membered macrolide, azithromycin. However, the erythromycin-resistant S. pyogenes isolates retained full susceptibility to spiramycin and josamycin (16-membered agents). These latter two antibiotics were also more active than the other macrolides against erythromycin-resistant S. pneumoniae isolates, especially josamycin which was 8-64 times more active than erythromycin; spiramycin was only two to eight times more active than erythromycin.
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Antibacterianos/farmacologia , Eritromicina/farmacologia , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pyogenes/efeitos dos fármacos , Resistência Microbiana a Medicamentos/genética , Resistência a Múltiplos Medicamentos , Genes Bacterianos , Humanos , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/microbiologia , África do Sul , Infecções Estreptocócicas/microbiologia , Streptococcus pneumoniae/genéticaRESUMO
This paper summarises the developmental activities for an electronic patient record system in diabetology based on GALEN technologies. It focusses on the modelling of primarily terminological medical knowledge of this subspecialty and describes its application for predictive data entry.
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Diabetes Mellitus/classificação , Sistemas Computadorizados de Registros Médicos , Processamento de Linguagem Natural , Terminologia como Assunto , Alemanha , Humanos , Armazenamento e Recuperação da Informação , Modelos TeóricosRESUMO
Morphological and ultrastructural features of the salivary glands and proboscises of Placobdella ornata, Placobdella parasitica, and Desserobdella picta were studied by light and electron microscopy. Chemical composition of the salivary cells was investigated using a variety of histochemical techniques. Placobdella ornata and P. parasitica have compact salivary glands with discrete pairs of anterior and posterior glands, while the salivary cells contain one mucous and three proteinaceous secretions. Salivary glands of D. picta are diffusely arranged and contain two mucous and two proteinaceous secretions. A cobalt-lysine forward-filling technique revealed that individual salivary cells consist of a roughly spherical soma and an elongated ductule. The majority of the internal space in a salivary soma is densely packed with spherical secretory granules which displace the cytoplasm to the periphery of the cell. Bundles of individual ductules enter the base of the proboscis on opposite sides and extend anteriorly. The ductules, also packed with secretory granules, are surrounded by microtubules associated with agranular endoplasmic reticulum, and merge with deep invaginations of the proboscis cuticle. The secretory granules are released at the end of these invaginations or pores. Pores were found on the tip, along the body, and on the luminal wall of the proboscises in all three species.
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Sanguessugas/anatomia & histologia , Glândulas Salivares/anatomia & histologia , Animais , Citoplasma/ultraestrutura , Grânulos Citoplasmáticos/ultraestrutura , Retículo Endoplasmático/ultraestrutura , Histocitoquímica , Sanguessugas/classificação , Microscopia Eletrônica , Microtúbulos/ultraestrutura , Especificidade da EspécieRESUMO
Many approaches for the development of computer-based patient record (CPR) systems consider only implicitly the inferences a user wants to accomplish in using the system. However, the integration of knowledge-based support into the routine work flow requires an explicit model of the inferences during routine work. Such a model helps to structure the interface of the system and to identify those inference steps which could benefit from knowledge-based support. This paper describes the approach used in developing a CPR system taking into account its future role as a platform for the integration of knowledge bases into routine work.
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Instituições de Assistência Ambulatorial , Inteligência Artificial , Diabetes Mellitus/terapia , Sistemas Computadorizados de Registros Médicos , Garantia da Qualidade dos Cuidados de Saúde , Diagnóstico por Computador , Interface Usuário-ComputadorRESUMO
We have examined the developing rat, mouse and marmoset globus pallidus for evidence of cells dying by a process of "naturally occurring" or programmed cell death. We have demonstrated that cells in the developing mammalian globus pallidus die by a process of apoptosis and that by day 7 after birth many of the apoptotic cells possess a neuronal phenotype. Light microscopic and ultrastructural evidence of apoptotic cell death included cell shrinkage, blebbing of the extracellular membrane and condensation of the nuclear chromatin. Additionally we used an in situ nick translation method to assess the integrity of the DNA within the dying cells. This revealed that cells with the morphological characteristics of apoptosis also possessed fragmented DNA typical of cells undergoing Type 1 programmed or apoptotic cell death. The lack of lysosomal enzyme activity within the dying cells and the frequent observations of phagocytosis by neighbouring cells also suggest that the form of programmed cell death is apoptosis and not Type 2 autophagic degeneration. We found no evidence for cells dying by Type 3 non-lysosomal degeneration since all dying cells examined under the electron microscope possessed intact intracellular organelles and cell membranes. We developed a sensitive silver stain which detected balls of condensed chromatin within the apoptotic cells. This enabled identification of apoptotic cells in the developing globus pallidus at low magnification and so allowed us to map the numbers and distribution of dying cells with time. The incidence of apoptotic cells in the neonatal globus pallidus was greatest at birth and then declined such that few cells were detected at one week and none was seen in the adult rat. Although the loss of large numbers of cells in the developing nervous system is a well documented phenomenon, there are only a limited number of reports of the mechanism by which neuronal cells die, and few of these are in the developing mammalian brain. There are at least four different morphological categories of neuronal cell death which are discriminated on morphological and biochemical criteria. Our analysis suggests that apoptotic or Type 1 cell death is the major form of programmed cell death occurring in the mammalian globus pallidus in the first week of life. This report also describes the use of two methods for the ready identification of apoptotic cells at the light microscope level. Because these methods are suitable for use on tissue sections they provide a means to assess the incidence of apoptotic cell death, in parallel with other analyses of the expression of gene products which control cell fate.
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Animais Recém-Nascidos/fisiologia , Apoptose/fisiologia , Globo Pálido/fisiologia , Neurônios/fisiologia , Fosfatase Ácida/metabolismo , Animais , Callithrix , Contagem de Células , Cromatina/metabolismo , DNA/química , Globo Pálido/citologia , Histocitoquímica , Hibridização In Situ , Camundongos , Microscopia Eletrônica , Microscopia de Fluorescência , Ratos , Ratos Sprague-Dawley , Coloração pela PrataRESUMO
Because of the rich blood supply ischemic necrosis of the tongue is extremely rare. But if it happens though, the reason is most often due to temporal arteritis. It predominantly occurs in elderly women, like in our case. The correct diagnosis should be established as soon as possible because high-dose cortisone therapy both relieves the patient's complaints and prevents life-threatening complications.
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Arterite de Células Gigantes/patologia , Isquemia/patologia , Língua/irrigação sanguínea , Idoso , Idoso de 80 Anos ou mais , Cortisona/uso terapêutico , Feminino , Arterite de Células Gigantes/tratamento farmacológico , Humanos , Isquemia/tratamento farmacológico , Necrose , Artérias Temporais/patologia , Língua/patologiaRESUMO
As the ideal contraceptive has not been found after a quarter century of global contraception research, this is an attempt to assess the advantages and drawbacks of the so-called "safe" methods of contraception currently in use. The most persuasive arguments in favour of oral contraceptives which other reversible methods cannot claim are their unsurpassed safety as well as the simplicity of their application. The disadvantage of potential damages through the perennial intake of hormones can be minimized with the low dosages of modern compounds. Recommendations are made concerning the controlled use of the various kinds of ovulation-inhibitors. Likewise, the use of ovulation-inhibitors with adolescents, at the end of reproductive age, and with women afflicted with diabetes mellitus are discussed. Advantages and drawbacks of contraception through the exclusive use of progestagen are briefly stated. Despite good applicability in single cases, intrauterine contraception should rather be viewed as a second choice only. Yet the standard problems, such as menstrual disturbances, increased tendency toward inflammations and individual incompatibility remain unsolved. Moreover, the rate of failure of 3% is ten times as high as with the ovulation-inhibitors. In their instructions some producers recommend too short a period of placement of the device in the uterus. Most IUD's can stay in place for a longer period of time. Repeated references to the possible complications of the use of IUD's with nulliparous women are made. As an emergency method to prevent a pregnancy after intercourse without contraceptives a hormonal method as well as the post-coital insertion of an IUD are discussed. After completed family planning the definitive sterilization presents itself as the ideal method of contraception, either through tubal sterilization in case of the woman, or vasectomy in case of the man. Rates of complications, failure rates, and chances of reversibility of both methods are specified.
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Anticoncepção/métodos , Áustria , Anticoncepcionais Orais Hormonais/administração & dosagem , Anticoncepcionais Orais Hormonais/efeitos adversos , Anticoncepcionais Pós-Coito/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Humanos , Expulsão de Dispositivo Intrauterino/efeitos adversos , Dispositivos Intrauterinos/efeitos adversos , Masculino , Gravidez , Risco , Reversão da Esterilização/métodos , Esterilização Tubária/métodos , Vasectomia/métodosRESUMO
Photochemical oxidants (O3, PAN, HCHO) are the typical pollutants in photochemical Smog. They can be formed as the result of the sunlight induced oxidation of precursor pollutants emitted into the atmosphere (NOx, CxHy). Other important precursor substances and reactive intermediates are compounds of the organic hydroxyl group (-O-H, for instance the methoxy radical CH3O), hydroxyl radical .OH, hydroperoxy radical HO2, and singlet oxygen O. For the production of photochemical oxidants in smog, especially ozone, NOx primarily act as catalysator. But CxHy serve as "combustibles". The quantities of the several formed photooxidants are mainly dependent on intensity and duration of daily sunshine, temperature, oxidant concentrations at the beginning of a build-up period, and on emission rates and concentrations of primary pollutants (NO, CxHy). Maximum mixing ratios of secondary pollutants often occur at certain distances downwind of primary pollutant sources, dependent on meteorological conditions (wind velocity, rel. humidity, etc.) and on rate constants for oxidant formation cycles. During the period of July 5 to 11, 1984, for instance, 6 kilometers SW from Zürich we found maximum ground-level mixing ratios of about 150 ppbv ozone, 4 ppbv PAN and 9 ppbv formaldehyde, that is 5 (ozone) to 10 (PAN) times above the supposed oxidant concentrations of unpolluted continental air. The increase in ozone in the late morning and early afternoon is accompanied by an increase in PAN and HCHO and by a decrease in NOx. This shows that in this case HCHO originates from photochemical reactions rather than being emitted directly to the atmosphere from vehicles.(ABSTRACT TRUNCATED AT 250 WORDS)