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In this paper, the preparation of low-cost samples, for the calibration of an energy-dispersive X-ray fluorescence system is presented. The entire procedure is proposed as an undergraduate or postgraduate student laboratory activity, which aims to familiarize students with the procedure of calibration of a spectroscopy-based analytical method through the XRF technique. Furthermore, the use of XRF for the determination of elemental concentrations in samples related to students' interests, was attempted.
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This paper presents the approach, assumptions, and computational analysis of the preliminary safety assessment, regarding the post-closure period for the disposal of radioactive waste in Greece. The assessment was implemented in the context of the National Program for the disposal of radioactive waste in the country, which is currently in the early stage for the investigation of facility siting. The basis scenario selected for this investigation was the leaching of radionuclides and the exposure in a residence offsite. Moreover, a scenario involving the intrusion in the facility and construction of a dwelling that disturbs the disposal zone is also considered. Due to the significant uncertainties in the current phase, the simulations related to leaching of the waste both in the offsite and intrusion scenarios are based on an uncertainty analysis with 25 site and scenario related parameters. The most important contribution is attributed to Ra-226 with an annual dose equal to about 2 and 3 µSv per MBq disposed, for the offsite and intrusion scenario, respectively. Th-232, Cl-36, C-14, Ag-108m and Pu-239 follow with a dose one order of magnitude less, compared to Ra-226. In the leaching scenarios examined, and for the most dose relevant radionuclides, the exposure related to drinking water from the well and the use of this water to irrigate fruits and vegetables are by far the dominant pathways due to the environmental transfer of the radionuclides and their associated dose coefficients. Th-232 dominates the direct exposure pathways (direct external radiation and plant contamination from the contaminated surface soil) in the intrusion scenario with an annual dose of about 1.4 mSv per Bq/g disposed. Ra-226, Cl-36 and Ag-108m cause exposure levels higher than 0.2 mSv/y per Bq/g disposed in the facility. A wide range was considered for the uncertainty parameters that led to a significant variation in the predicted doses that is expected to envelope the potential exposure for each radionuclide.
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Plutônio , Monitoramento de Radiação , Resíduos Radioativos , Poluentes Radioativos do Solo , Resíduos Radioativos/análise , Plutônio/análise , Grécia , Poluentes Radioativos do Solo/análiseRESUMO
This dataset manuscript describes the preparation procedure and lists the preconcentration efficiency of 112 ligands, immobilized on solid-state polymer membranes, for pollutants/elements monitoring in tap water and in environmentally relevant water matrices. Specifically, the energy dispersive X-ray fluorescence (EDXRF) spectra are presented, along with the preconcentration efficiency of each ligand in tap water. The main materials required for membrane preparation include the membrane matrix, a plasticizer, an ionophore, a catalyst (used only when producing anion-selective membranes), and a complexing agent, i.e. ligand. These are simply mixed, applied on a desired surface, here on a BoPET (biaxially-oriented polyethylene terephthalate) film (Mylar®), and left to dry and solidify, producing anion- or cation-selective membranes. Once the membranes are produced, they can be used even by non-specialised personnel directly on the field, which could be of particular importance for low and middle income countries (LMIC) and for remote or insular areas. The membranes can be functionalised with different ligands, suggesting that they can be used for identifying a vast array of different pollutants/elements in water matrices. Here a dataset of 112 ligands, immobilized on anion-selective membranes, are presented in terms of calcium (Ca), iron (Fe), nickel (Ni), zinc (Zn), antimony (Sb), lanthanum (La), uranium (U), copper (Cu), and gold (Au) preconcentration in tap water. Strontium (Sr) was also attempted to be measured, however, quantifiable results were not obtained. Furthermore, data for mercury (Hg) preconcentration, in cation-selective membranes, are also given. The enclosed data show that the most promising ligand for Hg, Ca, Fe, Ni, Zn, Sr, La, U, Cu, and Au preconcentration were 4-(2-Pyridylazo)resorcinol, Eriochrome Black T, di-Ammonium hydrogen citrate, 1,5-Diphenylcarbazide, dithizone, 1,1'-Carbonyldiimidazole, Bis(cyclopentadienyl)titanium dichloride, sodium dibenzyldithiocarbamate, calconcarbonsaure, and dibenzoylmethane, respectively. Interpretation of the data can be found in our previous work [1]. Overall, the main intention of this dataset manuscript is to communicate and promote the adoption of the proposed method by researchers and the water industry alike. This could further advance the method and encourage the assessment of additional ligands or/and pollutants/elements, including heavy metals which are typically found in water.
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Reperfusion injury of the liver occurs in liver transplantation and in major hepatectomies. It triggers a severe oxidative stress that leads to increased lipid peroxidation. In our study we examined the effect of parenteral supranutritional administration of alpha-tocopherol, a vitamin that plays a key role in the endogenous antioxidant system, to rats subjected to severe ischemia/reperfusion (I/R) injury of the liver. alpha-Tocopherol was administered to the animals at doses of 30 and 300 mg/kg bw, whereas total hepatic ischemia was induced for 60 min followed by 120 min reperfusion. Tissue and blood samples were collected for malonyldialdehyde (MDA) and serum alpha-tocopherol assay, respectively. In the sham operation group, mean MDA level in liver was 1.14 nmole/g wet tissue in the control subgroup, and 1.01 or 0.74 nmole/g wet tissue in the subgroups given 30 or 300 mg/kg alpha-tocopherol. In the I/R group, mean MDA level was 1.57 nmole/g wet tissue in the control subgroup, and 0.97 and 0.77 nmole/g wet tissue in the subgroups given 30 or 300 mg/kg alpha-tocopherol. Mean levels of alpha-tocopherol in serum (mumole/l) were 10.20 and 1.80 in the control subgroups, 25.28 and 11.25 in the subgroups treated with 30 and 300 mg/kg bw of alpha-tocopherol, and 31.00 and 13.02 in the subgroups treated with 30 and 300 mg/kg bw of alpha-tocopherol, within the sham-operation and I/R groups, respectively. A significant decrease of MDA accompanied by a significant increase of serum alpha-tocopherol was documented in the alpha-tocopherol-treated rats within both groups. Ischemia/reperfusion triggered a significant increase of the MDA level in the liver of the rats not treated with alpha-tocopherol as compares with the treated animals.
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Peroxidação de Lipídeos/fisiologia , Fígado/metabolismo , Fígado/patologia , Traumatismo por Reperfusão/metabolismo , alfa-Tocoferol/metabolismo , Animais , Fígado/cirurgia , Transplante de Fígado/efeitos adversos , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo , Ratos , Ratos Wistar , alfa-Tocoferol/sangueRESUMO
The Connecticut Department of Mental Health began creating assertive community treatment teams in 1987. The authors describe the approach taken by the department in defining the assertive community treatment model, in creating new assertive community treatment teams, and in monitoring the creation and functioning of these teams to ensure that fidelity to the assertive community treatment model is maintained. Assertive community treatment teams can be created even in the absence of funding for new staff by reconfiguring current community-based staff and by moving staff from state hospitals to the community. Preliminary data from a randomized trial in Connecticut comparing assertive community treatment with high-quality case management in areas with an array of community services indicated that the intended models were replicated, with variations in practice style across programs. Clients in assertive community treatment were in the hospital about half as often as clients in standard services and were also less likely to be without a permanent residence. Training and ongoing monitoring of assertive community treatment teams are necessary to detect practices that diverge from the intervention model so that corrective action can be taken.
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Serviços Comunitários de Saúde Mental/tendências , Equipe de Assistência ao Paciente/tendências , Esquizofrenia/reabilitação , Psicologia do Esquizofrênico , Adulto , Administração de Caso/tendências , Connecticut , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
The object of this research is to investigate the ways and the degree of contamination of Cretan grapes from the area of Chania and their alcoholic products, with the elements aluminium, arsenic, cadmium, copper, chromium, iron, lead, manganese, nickel and zinc. Fifteen samples of grapes were collected and used for the production of experimental wines from rinsed and unrinsed grapes. A microwave furnace was used for the digestion and dissolution of the experimental wines, the precipitates that originated in these wines, as well as the wines of the corresponding producers. The analyses of all mentioned samples as well as 34 local alcoholic distillates were performed using total reflection X-ray fluorescence and graphite furnace atomic absorption spectrometry. The concentrations for all the elements that were determined were almost in all cases, well below the maximum permissible levels by the Greek and the European Union legislation.
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Oligoelementos/análise , Vinho , Grécia , Espectrofotometria AtômicaRESUMO
BACKGROUND/AIMS: The implication of lipid peroxidation in the inhibitory effect of GdCl3 (gadolinium chloride) on Kupffer cells activation has not been extensively investigated. The aim of this study was to examine the effect of GdCl3 inhibition of Kupffer cells activation on lipid peroxidation after severe total hepatic ischemia/reperfusion. METHODOLOGY: Male Wistar rats (n = 40) were randomly divided into a sham-operation group, a control ischemia/reperfusion group, and two ischemia/reperfusion groups pretreated with GdCl3 (10 mg and 20 mg/kg bw intravenously, 48 and 24 h prior to operation). Following 60 min of total hepatic ischemia and 120 min of reperfusion, the rats were sacrificed, and liver samples were taken for determination of malondialdehyde and light microscopy examination. Blood samples were also taken for assay of aspartate and alanine transaminase. Additional animals (n = 60) were followed up for a 7-day survival rate determination. RESULTS: Ischemia/reperfusion decreased the survival rate to 13.3%, increased (p < 0.001) the levels of aspartate and alanine transaminase in serum to 2387 +/- 75 and 2157 +/- 87 IU/L, respectively, and increased (p < 0.001) malondialdehyde levels in liver to 1.609 +/- 0.096 nmoles/g compared with 1.164 +/- 0.060 in the sham operation group. Pretreatment with GdCl3 increased the survival rate to 60%, and decreased (p < 0.001) the levels of aspartate transaminase in serum to 1549 +/- 66 and 1496 +/- 55 IU/L, the levels of alanine transaminase in serum to 1302 +/- 48 and 1305 +/- 63 IU/L, and the levels of malondialdehyde in liver to 1.132 +/- 0.034 and 1.149 +/- 0.57 nmoles/g for the lower and the higher doses of GdCl3, respectively. Histological examination showed protection of liver parenchyma in the animals treated with GdCl3. CONCLUSIONS: Experimental data suggest that GdCl3 inhibition of Kupffer cells activation protects liver from ischemia/reperfusion injury by a mechanism that reduces lipid peroxidation.
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Gadolínio/farmacologia , Células de Kupffer/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Traumatismo por Reperfusão/fisiopatologia , Animais , Células de Kupffer/fisiologia , Peroxidação de Lipídeos/fisiologia , Masculino , Ratos , Ratos Wistar , Traumatismo por Reperfusão/prevenção & controleRESUMO
Clients who were high service users with serious mental disorders were randomly assigned to assertive community treatment (ACT) or to standard case management (SCM) at three sites and followed for 18 months. Clients in ACT spent more days in the community than did those in SCM, at no additional cost. For clients who were hospitalized at study entry, assertive community treatment was more cost-effective than standard case management.
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Serviços Comunitários de Saúde Mental/economia , Desinstitucionalização/economia , Equipe de Assistência ao Paciente/economia , Transtornos Psicóticos/economia , Adulto , Idoso , Administração de Caso/economia , Connecticut , Análise Custo-Benefício , Feminino , Mau Uso de Serviços de Saúde/economia , Humanos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente/economiaRESUMO
A new technique for the restoration of the continuity of the colon with preservation of an existing colostomy is described here. A 75-year-old male with a three-year history of abdominal-perineal resection and a well functioning end colostomy was admitted to our department for a second primary cancer of the descending colon. At operation the colon was divided close to the abdominal wall; the colostomy was left in situ while the descending colon and mesocolon were radically resected. The viability of the colostomy was being continuously inspected. An EEA stapler was then inserted through the colostomy and an anastomosis was created. Shortening the length of the operation and avoiding the possible complications that follow the creation of a new stoma are the major benefits of the technique. Still, the viability of the colostomy after its separation of the rest of the colon and mesocolon has to be ensured before proceeding.
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Colectomia/métodos , Neoplasias do Colo/cirurgia , Colostomia/métodos , Segunda Neoplasia Primária/cirurgia , Complicações Pós-Operatórias/cirurgia , Neoplasias Retais/cirurgia , Idoso , Anastomose Cirúrgica/métodos , Colonoscopia/métodos , Humanos , Masculino , Reoperação , Grampeadores CirúrgicosRESUMO
BACKGROUND: To find a safe and effective method of pelvic reconstruction after abdominoperineal resection in order to prevent small intestine from descending into the pelvis. This allows safe delivery of optimal doses of radiation therapy, which exceed radiation tolerance of the small intestine, in advanced stages of colorectal cancer. MATERIALS: Prospective, ongoing study examining patients who underwent abdominoperineal resection and pelvic reconstruction with full-thickness skin grafts. METHODS: Nine (9) patients underwent abdominoperineal resection of the rectum and pelvic reconstruction with full-thickness skin grafts for colorectal cancer stage C. Subsequently they were referred for adjuvant radiation therapy and followed up regularly for surgical complications and disease recurrence. RESULTS: All patients successfully completed postoperative radiation therapy and there were no serious surgical complications pertaining to the initial operation and the skin homeotransplantation. None of the patients needed reoperation, so the long-term outcome of the transplantation was not surgically evaluated. CONCLUSIONS: Reconstruction of the peritoneal gap after abdominoperineal resection of the rectum with full-thickness skin graft is a safe and effective method. The small intestine was effectively excluded from the pelvis allowing successful completion of adjuvant radiation therapy with minimal irradiation of the small intestine and effective prevention of radiation enteritis.
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Procedimentos de Cirurgia Plástica/métodos , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Transplante de Pele/métodos , Colectomia/métodos , Feminino , Seguimentos , Humanos , Laparotomia/métodos , Masculino , Pelve , Períneo/cirurgia , Cuidados Pós-Operatórios/métodos , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Radioterapia Adjuvante , Neoplasias Retais/mortalidade , Espaço Retroperitoneal , Medição de Risco , Transplante de Pele/efeitos adversos , Retalhos Cirúrgicos/irrigação sanguínea , Análise de Sobrevida , Coleta de Tecidos e Órgãos , Resultado do TratamentoRESUMO
We present our experience with the use of the intraluminal stapler device for the purpose of creating of a dermal permanent colostomy, in cases of acute emergency operations and of regular programmed operations. The advantages of this method for those surgeons who use stapling devices are: controlled safety of the colostomy, shorter operation time and the creation of a stable diameter of the colostomy. All patients of this category as well as those having been operated on for colon cancer have been placed on a protocol follow up for three years and are closely monitored. This has allowed us to closely follow these patients in cases of complications.