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Potassium-40 is a widespread, naturally occurring isotope whose radioactivity impacts subatomic rare-event searches, nuclear structure theory, and estimated geological ages. A predicted electron-capture decay directly to the ground state of argon-40 has never been observed. The KDK (potassium decay) collaboration reports strong evidence of this rare decay mode. A blinded analysis reveals a nonzero ratio of intensities of ground-state electron-captures (I_{EC^{0}}) over excited-state ones (I_{EC^{*}}) of I_{EC^{0}}/I_{EC^{*}}=0.0095±[over stat]0.0022±[over sys]0.0010 (68% C.L.), with the null hypothesis rejected at 4σ. In terms of branching ratio, this signal yields I_{EC^{0}}=0.098%±[over stat]0.023%±[over sys]0.010%, roughly half of the commonly used prediction, with consequences for various fields [27L. Hariasz et al., companion paper, Phys. Rev. C 108, 014327 (2023)PRVCAN2469-998510.1103/PhysRevC.108.014327].
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Methane emissions from active or closed landfills can be reduced by means of methane oxidation enhanced in properly designed landfill covers, known as "biocovers". Biocovers usually consist of a coarse gas distribution layer to balance gas fluxes placed beneath an appropriate substrate layer. The application of such covers implies use of measurement methods and evaluation approaches, both during the planning stage and throughout the operation of biocovers in order to demonstrate their efficiency. Principally, various techniques, commonly used to monitor landfill surface emissions, can be applied to control biocovers. However, particularly when using engineered materials such as compost substrates, biocovers often feature several altered, specific properties when compared to conventional covers, e.g., respect to gas permeability, physical parameters including water retention capacity and texture, and methane oxidation activity. Therefore, existing measuring methods should be carefully evaluated or even modified prior to application on biocovers. This paper discusses possible strategies to be applied in monitoring biocover functionality. On the basis of experiences derived from investigations and large-scale field trials with compost biocovers in Austria, an assessment approach has been developed. A conceptual draft for monitoring biocover performance and recommendations for practical application are presented.
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Estudos de Avaliação como Assunto , Metano/análise , Gerenciamento de Resíduos , Áustria , Oxirredução , Solo , Microbiologia do SoloRESUMO
Fourier transform infrared (FTIR) spectroscopy combined with multivariate data analysis is under development as a method to classify waste materials. The chemical composition of the sample is reflected by a series of regions of the infrared spectrum which are used as variables for multivariate data analysis. In this study, separated biowaste collection, mechanically-biologically treated waste (MBT-waste), and old landfill materials were collected to provide materials representing different stages of decomposition. A total of 819 FTIR absorbance spectra were recorded. Principal component analyses (PCA) were performed followed by soft independent modeling of class analogy (SIMCA) for classification of waste materials. Strong classification occurred for an analysis where spectral carbonate regions were included, and for another analysis when they were not. The SIMCA model enabled the differentiation and the classification of unknown samples according to the three categories in both cases. The classification methods developed here provide an assessment tool that regulatory authorities may wish to explore when assessing whether a treated waste from an uncertain process can be classed as compost or MBT-waste.
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Resíduos/classificação , Modelos Teóricos , Análise Multivariada , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier , Resíduos/análiseRESUMO
A new upgrading process for biogas and landfill gas (LFG) has been designed recently by the authors' institute. The process uses the alkalinity of the fine fraction of bottom ash from municipal solid waste incineration (MSWI) for sorbing CO2 and H2S. Results from process development and optimisation are presented in this paper. It is expected that nearly pure CH4 can be produced for substitution of fossil fuels. Simultaneously, the leachability of MSWI bottom ash is clearly reduced.
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Gases , Anaerobiose , Projetos PilotoRESUMO
Emissions from old landfills via leachate and the gas phase are influenced by state and stability of the organic matter in the solid waste and by environmental conditions within the landfill. Remediation of landfills by means of in-situ aeration is one possibility to reduce these emissions. By establishing aerobic conditions, biological processes in the landfill are accelerated. To investigate the effects of this remediation technology, lab-scale experiments with column tests have been carried out. The main goal of the present work is to characterize the changes of the carbon and nitrogen compounds in the aerated solid waste, the leachate and the gas phase under varying conditions. The results demonstrate a clear reduction of emissions and a stabilization of the organic matter. Furthermore, it is shown that both the intensity of aeration and the amount of water affect biological processes to a certain extent. Even when columns were operated under anaerobic conditions after a long running period of aeration, the emissions remained low.
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Poluentes Atmosféricos/análise , Eliminação de Resíduos/métodos , Poluentes Químicos da Água/análise , Poluição do Ar/prevenção & controle , Carbono/análise , Dióxido de Carbono/análise , Metano/análise , Nitratos/análise , Nitrogênio/análise , Compostos de Amônio Quaternário/análise , Resíduos/análise , Resíduos/classificaçãoRESUMO
BACKGROUND & AIMS: Weight loss and malnutrition are frequent problems in oncology patients. The aim of this study was to get a perspective of the current practice of parenteral nutrition (PN) care in an outpatient setting and to improve patient-centered nutritional care. METHODS: Fifty-three outpatient oncology centers participated in this observational study performed between July 2010 and March 2011. All participating centers entered data online into a web-based documentation form, containing a number of oncology patients, diagnoses, and detailed data about oncology patients receiving PN. RESULTS: Two cohorts were analyzed. First cohort consisted of all oncology patients in quarter 04/2010. Second cohort consisted of patients with PN during the whole studying period. In the first cohort 2.46% (n = 626) of 25,424 oncology patients received PN. Most frequent diagnoses of patients receiving PN were gastric cancer (n = 119) and colorectal cancer (n = 104), however most stated diagnosis was "other" (n = 163). In the second cohort (n = 1137), a common indication for PN was impaired gastrointestinal passage (n = 177), although here again most stated reason was "other" (n = 924). In the course of the PN treatment, patients (n = 1137) showed a stable or slowly increasing body mass index (from 21.6 ± 3.8 kg/m(2) to 21.8 ± 3.5 kg/m(2)). CONCLUSION: This is the largest study outlining the characteristics of oncology patients in the context of PN in German ambulatory centers. They confirm the important role of PN in the care of gastrointestinal cancer. Further studies have to be performed to identify if other indications than those mentioned in relevant guidelines can trigger initiation of PN.
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Neoplasias Gastrointestinais/dietoterapia , Oncologia/métodos , Terapia Nutricional/métodos , Nutrição Parenteral/métodos , Assistência ao Paciente/métodos , Idoso , Índice de Massa Corporal , Feminino , Neoplasias Gastrointestinais/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Nutricional/normas , Terapia Nutricional/tendências , Observação , Nutrição Parenteral/efeitos adversos , Guias de Prática Clínica como Assunto , Estudos Retrospectivos , Resultado do TratamentoRESUMO
This study comprises a total of 141 patients with suspected primary and recurrent colorectal carcinomas, in whom immunoscintigraphy with 99mTc-Mab BW 431/26 was performed. Whole-body scans were done 5.5 hr and SPECT imaging of the abdominal region was done at 6 and 24 hr postinjection of 1100 MBq 99mTc-labeled Mab (1 mg). In the course of primary tumor identification (n = 65), sensitivity of anti-CEA immunoscintigraphy was 95%, specificity 91%. In the diagnosis of early recurrences (n = 76), immunoscintigraphy was the method of choice to clarify the problem (sensitivity 94%; specificity 86%). Overall sensitivity of immunoscintigraphy in patients with suspected colorectal carcinomas and early recurrences was 95%, specificity 88%. Human anti-mouse antibodies were found in 29% (80% predominantly anti-isotypic, 20% predominantly anti-idiotypic). In contrast to anti-CEA immunoscintigraphy, the results of serum CEA levels were rather disappointing. Only 18 out of the 43 surgically verified primary colorectal carcinomas and 17 out of 32 patients with recurrences showed elevated serum CEA levels. In our clinical experience with this 99mTc-labeled anti-CEA antibody, immunoscintigraphy can play an important role in the identification of early colorectal recurrences and in postoperative colorectal cancer patients it should be performed in cases with unclear transmission computed tomography.
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Anticorpos Monoclonais , Antígeno Carcinoembrionário/imunologia , Neoplasias do Colo/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Neoplasias Retais/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígeno Carcinoembrionário/sangue , Neoplasias do Colo/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/imunologia , Neoplasias Retais/imunologia , Tecnécio , Tomografia Computadorizada de Emissão de Fóton ÚnicoRESUMO
A total of 60 patients with advanced breast cancer were treated with a combination of prednimustine (P: 110 mg/m2, days 1-5), mitoxantrone (M: 12 mg/m2, day 1) and 5-fluorouracil (F: 500 mg/m2, day 1) (PMF). Treatment was repeated every 3 weeks. In all 53 patients were evaluable for response. A total of 12 subjects had failed prior chemotherapy for metastatic disease. In response to PMF treatment we observed 21 partial remissions and 3 complete remissions, amounting to a total response rate of 45%. The median duration of response was 39 weeks, and median survival was 56 weeks. Dose-limiting side effects were leukopenia (40 cases) and thrombocytopenia (11 patients). Nausea and vomiting was experienced by 93% of subjects; in 56% of cases it reached WHO stage II-III. Alopecia occurred in 18% of our patients. Our results suggest that PMF represents an active regimen in the treatment of advanced breast cancer and yields a response rate of 45%. Considering that the majority of our patients had not received prior chemotherapy, the question remains open as to whether a 45% response rate outweighs the observed toxicity.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/mortalidade , Distribuição de Qui-Quadrado , Avaliação de Medicamentos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Leucopenia/induzido quimicamente , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Mitoxantrona/efeitos adversos , Náusea/induzido quimicamente , Prednimustina/administração & dosagem , Prednimustina/efeitos adversos , Indução de Remissão , Taxa de Sobrevida , Trombocitopenia/induzido quimicamente , Vômito/induzido quimicamenteRESUMO
BACKGROUND: This study was performed to determine if postoperative serial monitoring of rectal cancer patients can be performed with an immunoscintigraphic imaging test for carcinoembryonic antigen (CEA). It was also of interest to assess whether this test, in combination with standard monitoring procedures used in an intensive surveillance plan, can result in the identification of surgically salvageable patients. STUDY DESIGN: Forty consecutive resected Dukes' B and C rectal cancer patients underwent a prospective, single-institution, surveillance trial of physical examination (including digital rectal examination), endoscopy, CT of the abdomen and pelvis, liver ultrasound, chest x-ray, blood CEA, and CEA immunoscintigraphy with arcitumomab (CEA-Scan, Immunomedics, Morris Plains, NJ) every 6 months for the first 2 years and every 12 months for the next 3 years after initial operation. Outcomes were compared with those from a similar group of 69 patients treated previously at the same institution but without CEA imaging. RESULTS: A total of 219 CEA imaging studies were performed without any significant adverse effects or immune responses, and resulted in lesion sensitivity, specificity, accuracy, and positive and negative predictive values of 94.1%, 97.5%, 97.3%, 76.2%, and 99.5%, respectively. Of the 40 patients, 16 developed 22 surgically confirmed local or distant recurrences, and CEA imaging correctly disclosed 82% of these lesions pre-operatively. All of the patients found to have recurrences had at least one tumor site by CEA imaging; only 6 of 16 had elevated blood CEA titers. On a patient-basis, there was a sensitivity of 100%, a specificity of 79.2%, an accuracy of 87.5%, and positive and negative predictive values of 76.2% and 100%, respectively. The potential therapeutic benefit of serial arcitumomab imaging is suggested by the fact that 6 of 16 patients (37.5%) with recurrence underwent potentially curative second-look operations, compared with 6 of 69 (8.7%) of a comparable population studied at this institution during an earlier 6-year period, using all of the same tests except CEA imaging. None of the patients in this historic control group survived more than 21 months, although the mean survival of the six patients resected for cure in the study population was 35 months (range 11 to 69 months). During 6 years of followup, three of the six re-resected patients eventually died of cancer recurrence, two died from other causes (and were confirmed by necropsy to be tumor-free), and one patient is still free of disease in the sixth year. CEA scanning appeared to be more predictive of recurrence than blood CEA testing or other diagnostic modalities. CONCLUSIONS: Arcitumomab inclusion in intensive surveillance of patients with resected rectal cancer can disclose tumor recurrence at a stage that allowed surgical salvage therapy in 37.5% of the 16 patients with recurrence who had second-look surgery, and in 19% the patients were free of disease during longterm followup. This pilot study suggests that a randomized prospective trial comparing standard surveillance procedures to the use of CEA imaging added thereto should be undertaken.
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Adenocarcinoma/diagnóstico por imagem , Antígeno Carcinoembrionário/análise , Radioimunodetecção , Neoplasias Retais/diagnóstico por imagem , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ensaios Clínicos como Assunto , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Projetos Piloto , Valor Preditivo dos Testes , Estudos Prospectivos , Neoplasias Retais/mortalidade , Neoplasias Retais/cirurgia , Sensibilidade e EspecificidadeRESUMO
Anti-CEA-scintigraphy turned out to be very reliable in detecting primary and recurrent colorectal cancer, its overall accuracy being more than 90%. The intraoperative application of this technology should provide similar results when focussing at extrahepatic tumor deposits, for example in lymph nodes, thus allowing accurate staging of the underlying disease. To test this hypothesis we launched the following feasibility study the results of which are compared to those reported in the recent literature. We investigated 20 patients, six with rectum and 14 with colon cancer. 24 hours before surgery they were intravenously given 1 ml of a fab'-fragment-antibody to CEA, labeled with 25 mCi of 99mTc (CEA-Scan). During surgery the radioactivity in lymph glands regional to the tumors was measured and compared to the much lower activity in healthy nodes. For this we used a scintillation probe (C-Trak, Care Wise, Inc., Morgan Hill, CA). All lymph nodes of interest were then excised and submitted to frozen section pathology. In 7 out of 20 cases scintimetry led to an up-staging of the disease. In addition we found metastatic spread to lymph nodes that were basically not regional to the primary tumor (retroperitoneum, renal hilum etc.). Scintimetry can precisely identify even very small tumor deposits. So it leads to accurate staging while surgery is still ongoing. In a further step the concept of sentinel node diagnosis, which is right now being clinically evaluated, may some day be applied in colorectal surgical oncology.
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Adenocarcinoma/secundário , Anticorpos Monoclonais , Biomarcadores Tumorais/análise , Antígeno Carcinoembrionário/análise , Neoplasias do Colo/cirurgia , Cuidados Intraoperatórios/métodos , Metástase Linfática/diagnóstico , Compostos de Organotecnécio , Radioimunodetecção , Neoplasias Retais/cirurgia , Biópsia de Linfonodo Sentinela , Adenocarcinoma/química , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Idoso de 80 Anos ou mais , Animais , Neoplasias do Colo/química , Neoplasias do Colo/patologia , Estudos de Viabilidade , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Excisão de Linfonodo , Masculino , Camundongos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Peritoneais/diagnóstico por imagem , Neoplasias Peritoneais/secundário , Estudos Prospectivos , Radioimunodetecção/instrumentação , Compostos Radiofarmacêuticos , Neoplasias Retais/química , Neoplasias Retais/patologia , TecnécioRESUMO
Identification of biochemical changes induced by ethanol ingestion would aid in the diagnosis and management of many alcohol-related problems in man. In this paper we identify a pH 5.5 alpha-mannosidase activity in the rat which is affected by chronic ethanol consumption. Chronic (16 wk) ingestion of alcohol (36% of calories) causes the activity of this alpha-mannosidase (thought to be the cytosolic alpha-mannosidase) in liver to decrease by 50%. We hypothesize that this deficiency of (pH 5.5) alpha-mannosidase activity may account for the reduced rate of secretion of glycoproteins by livers of alcohol-fed rats reported by other investigators (Volentine et al, Hepatology 1987;7:490-495).
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Alcoolismo/enzimologia , Fígado/enzimologia , Manosidases/metabolismo , Animais , Cromatografia Líquida/métodos , Citosol/enzimologia , Glicoproteínas/biossíntese , Hidrolases/metabolismo , Lisossomos/enzimologia , Masculino , Manosidases/deficiência , Ratos , Ratos Endogâmicos , alfa-ManosidaseRESUMO
Stage-adjusted treatment of colorectal tumors requires precise knowledge of the extent of the underlying disease. Reliable staging is mandatory for intraoperative treatment planning. In this prospective trial monoclonal antibodies to CEA were labeled with 99mTc as tracer. Twenty patients were studied intraoperatively with a hand-held gamma detector. The results were compared to those obtained by all other diagnostic modalities and they were then confirmed by histopathology. Intraoperative scanning can reliably identify all tumor deposits and can confirm the radicality of the procedure. Thus, the use of immunoscintimetry is helpful in early decision making on adjuvant treatment modalities.
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Antígeno Carcinoembrionário/imunologia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/cirurgia , Tecnécio , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais , Neoplasias Colorretais/patologia , Feminino , Humanos , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória , Estadiamento de Neoplasias , CintilografiaRESUMO
Supraclavicular lymph node metastases appeared in a female patient six years after thyroidectomy, radioiodine therapy and external radiation for a follicular thyroid carcinoma and four years after mastectomy and lymphadenectomy for an invasive ductal breast cancer. It was not possible either by conventional imaging methods or by serological methods, to assign the metastases to one of the two primary tumors. Anti-CEA immunoscintigraphy and SPECT of the cervicothoracic region showed a circumscribed pathological uptake of 99mTc-labeled anti-CEA antibodies in the area of the supraclavicular lymph nodes. The preoperative suspicion of lymph-node infiltration by CEA-expressing breast cancer cells was confirmed histologically after surgical removal of the lymph nodes.
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Anticorpos Monoclonais , Neoplasias da Mama/patologia , Antígeno Carcinoembrionário/imunologia , Linfonodos/patologia , Neoplasias Primárias Múltiplas/patologia , Neoplasias da Glândula Tireoide/patologia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/imunologia , Adenocarcinoma/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/imunologia , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/imunologia , Carcinoma Intraductal não Infiltrante/patologia , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/imunologia , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/diagnóstico por imagem , Neoplasias Primárias Múltiplas/imunologia , Tecnécio , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/imunologia , Tomografia Computadorizada de Emissão de Fóton ÚnicoRESUMO
: Originally designed as position-sensitive detectors for particle tracking, silicon drift detectors (SDDs) are now used for high-count rate X-ray spectroscopy, operating close to room temperature. Their low-capacitance read-node concept places them among the fastest high-resolution detector systems. They have been used in a new spectrum of experiments in the wide field of X-ray spectroscopy: fluorescent analysis, diffractometry, materials analysis, and synchrotron experiments such as X-ray holography and element imaging in scanning electron microscopes. The fact that the detector system can be used at room temperature with good spectroscopic performance and at -10 degrees C with excellent energy resolution, avoiding liquid nitrogen for cooling and high-quality vacuum, guarantees a large variety of new applications, independent of the laboratory environment. A brief description of the device principles is followed by basics on low noise amplification. The performance results of a complete detector system are presented as well as some dedicated applications already realized, including use in a surface mapping instrument and use of a "mini-spectrometer" for the analysis of works of art. Fully depleted pn-charge-coupled devices (pn-CCDs) have been fabricated for the European X-ray Multi-Mirror mission (XMM) and the German X-ray satellite ABRIXAS, enabling high-speed, low-noise, position-resolving X-ray spectroscopy. The detector was designed and fabricated with a homogeneously sensitive area of 36 cm2. At -70 degrees C it has a noise of 4 e- rms, with a readout time of the total focal plane array of 4 msec. The maximum count rate for single photon counting was 10(5) cps under flat field conditions. In the integration mode, more than 10(9) cps can be detected at 6 keV. Its position resolution is on the order of 100 µm. The quantum efficiency is higher than 90%, ranging from carbon K X-rays (277 eV) up to 10 keV.
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The management of residues from thermal waste treatment is an integral part of waste management systems. The primary goal of managing incineration residues is to prevent any impact on our health or environment caused by unacceptable particulate, gaseous and/or solute emissions. This paper provides insight into the most important measures for putting this requirement into practice. It also offers an overview of the factors and processes affecting these mitigating measures as well as the short- and long-term behavior of residues from thermal waste treatment under different scenarios. General conditions affecting the emission rate of salts and metals are shown as well as factors relevant to mitigating measures or sources of gaseous emissions.
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Poluição do Ar/prevenção & controle , Eliminação de Resíduos , Arquitetura de Instituições de Saúde , Gases , IncineraçãoRESUMO
Since 1989 we have operated upon 28 patients for trans- or suprasphincteric fistula, using the mucosal sliding flap: After injection of a vasoconstrictory agent into the submucosal tissue we sparingly excise the inner opening of the fistula just beyond the dentate line. A mucosal flap is then meticulously dissected and used to cover the lesion in the rectum. The flap prevents fecal bacteria from invading the intrasphincteric portion of the fistula. This portion remains intact, and so does the sphincter apparatus. Then we excise the fistulous tract, proceeding from its external opening towards the sphincter muscle. After a mean follow-up of 8.1 months all 28 patients are free of symptoms. Proctoscopy did not reveal persistent or recurrent fistula in any of them.
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Canal Anal/cirurgia , Mucosa Intestinal/transplante , Fístula Retal/cirurgia , Retalhos Cirúrgicos , Adulto , Cirurgia Colorretal/métodos , Feminino , Seguimentos , Humanos , MasculinoRESUMO
Gaucher's disease is rare in association with pregnancy (we have only found 53 cases of women with this disease who had at least one pregnancy since 1945). A review of literature on this subject and this one case confirms that it is unlikely that the disease will progress as far as the symptomatology is concerned and that there are unlikely to be obstetric or fetal complications. All the same there are certain complications that can occur as the haematological state is concerned (thrombocytopenia, coagulation defects such as bleeding, particularly post-partum from the genital organs). Mechanical difficulties may occur because of the greatly enlarged spleen. Pregnancy is not contra-indicated but it is a high risk pregnancy that has to watched very carefully with ultrasound and great attention to the obstetric and biological condition.
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Doença de Gaucher , Complicações Hematológicas na Gravidez , Adulto , Feminino , Doença de Gaucher/patologia , Doença de Gaucher/fisiopatologia , Humanos , Gravidez , Complicações Hematológicas na Gravidez/patologiaRESUMO
The Austrian Landfill Ordinance provides limit values regarding the reactivity for the disposal of mechanically biologically treated (MBT) waste before landfilling. The potential reactivity determined by biological tests according to the Austrian Standards (OENORM S 2027 1-2) can be underestimated if the microbial community is affected by environmental conditions. New analytical tools have been developed as an alternative to error-prone and time-consuming biological tests. Fourier Transform Infrared (FT-IR) spectroscopy in association with Partial Least Squares Regression (PLS-R) was used to predict the reactivity parameters respiration activity (RA(4)) and gas generation sum (GS(21)) as well as to detect errors resulting from inhibiting effects on biological tests. For this purpose 250 MBT-waste samples from different Austrian MBT-plants were investigated using FT-IR spectroscopy in the mid (MIR) and near infrared (NIR) area and biological tests. Spectroscopic results were compared with those from biological tests. Arising problems caused by interferences of RA(4) and GS(21) are discussed. It is shown that FT-IR spectroscopy predicts RA(4) and GS(21) reliably to assess stability of MBT-waste materials and to detect errors.
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Monitoramento Ambiental/métodos , Análise Multivariada , Eliminação de Resíduos , Resíduos/análise , Áustria , Biodegradação Ambiental , Cidades , Monitoramento Ambiental/normas , Análise dos Mínimos Quadrados , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
In this work, we present the results of the experimental characterization of the DRAGO (DRift detector Array-based Gamma camera for Oncology), a detection system developed for high-spatial resolution gamma-ray imaging. This camera is based on a monolithic array of 77 silicon drift detectors (SDDs), with a total active area of 6.7 cm(2), coupled to a single 5-mm-thick CsI(Tl) scintillator crystal. The use of an array of SDDs provides a high quantum efficiency for the detection of the scintillation light together with a very low electronics noise. A very compact detection module based on the use of integrated readout circuits was developed. The performances achieved in gamma-ray imaging using this camera are reported here. When imaging a 0.2 mm collimated (57)Co source (122 keV) over different points of the active area, a spatial resolution ranging from 0.25 to 0.5 mm was measured. The depth-of-interaction capability of the detector, thanks to the use of a Maximum Likelihood reconstruction algorithm, was also investigated by imaging a collimated beam tilted to an angle of 45 degrees with respect to the scintillator surface. Finally, the imager was characterized with in vivo measurements on mice, in a real preclinical environment.