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The observation of neutrinoless double-beta (0νßß) decay would offer proof of lepton number violation, demonstrating that neutrinos are Majorana particles, while also helping us understand why there is more matter than antimatter in the Universe. If the decay is driven by the exchange of the three known light neutrinos, a discovery would, in addition, link the observed decay rate to the neutrino mass scale through a theoretical quantity known as the nuclear matrix element (NME). Accurate values of the NMEs for all nuclei considered for use in 0νßß experiments are therefore crucial for designing and interpreting those experiments. Here, we report the first comprehensive ab initio uncertainty quantification of the 0νßß-decay NME, in the key nucleus ^{76}Ge. Our method employs nuclear strong and weak interactions derived within chiral effective field theory and recently developed many-body emulators. Our result, with a conservative treatment of uncertainty, is an NME of 2.60_{-1.36}^{+1.28}, which, together with the best-existing half-life sensitivity and phase-space factor, sets an upper limit for effective neutrino mass of 187_{-62}^{+205} meV. The result is important for designing next-generation germanium detectors aiming to cover the entire inverted hierarchy region of neutrino masses.
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Monitored Dosage Systems (MDS) are an efficient, reliable and approved device for drug reconditioning in pharmacy. These systems imply a review on proper drug use and the collaboration between primary health care and pharmacists. The case study describes a female patient with a surgical intervention due to lumbosciatica in 2021 and 2022. Patient describes uncontrolled chronic pain and confusion related to improper drug use. During regular dispensing of her medication, these medicine-related problems (MRP) were detected and the patient was referred to the MDS service. After its implementation, the patient's confusion was eliminated and pain management was achieved, increasing her quality of life. As a conclusion, the different health services provided by the pharmacy can improve a patient's quality of life, treatment adherence and MRP detection.
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The nuclear shell model is one of the prime many-body methods to study the structure of atomic nuclei, but it is hampered by an exponential scaling on the basis size as the number of particles increases. We present a shell-model quantum circuit design strategy to find nuclear ground states by exploiting an adaptive variational quantum eigensolver algorithm. Our circuit implementation is in excellent agreement with classical shell-model simulations for a dozen of light and medium-mass nuclei, including neon and calcium isotopes. We quantify the circuit depth, width and number of gates to encode realistic shell-model wavefunctions. Our strategy also addresses explicitly energy measurements and the required number of circuits to perform them. Our simulated circuits approach the benchmark results exponentially with a polynomial scaling in quantum resources for each nucleus. This work paves the way for quantum computing shell-model studies across the nuclear chart and our quantum resource quantification may be used in configuration-interaction calculations of other fermionic systems.
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INTRODUCTION: The mothers of newborns who are discharged from a neonatal intensive care unit (NICU) experience stress and anxiety due to the specialized care their child requires at home, affecting their perception of maternal self-efficacy. OBJECTIVE: To evaluate the effect of the nursing intervention called Hospital Discharge Plan (HDP) on the promotion of self-efficacy in mothers of newborns discharged from the NICU. METHOD: Quantitative study, quasi-experimental design with pre-test/post-test in a single group, using the Parental Evaluation Scale applied to a convenience sample of 72 mothers of high-risk newborns from a NICU located in the city of Villavicencio (Colombia). The first measurement was taken between days 3 and 4 before discharge and at 15 days' post-discharge. Data processing was carried out using the statistical program SPSS, version 21. The intervention was based on the four concepts of self-efficacy by Barbara Resnick. RESULTS: The perception of maternal self-efficacy before the intervention showed a median of 8.9 points (RI 7.6-9.5); after the intervention it showed a median of 9.6 points (RI of 10-8.7); a statistically significant p-value<0.001 was obtained before and after the intervention with the Wilcoxon rank test. CONCLUSIONS: Education and follow-up promoted the development of knowledge and skills in mothers for the care of high-risk newborns. This contributed to the experience of mastery and vicarious experience from the teaching-learning process and contact with the experience of other mothers, which contributes to the effective development of motherhood.
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Individual monitoring of external radiation is an activity usually regulated by national regulatory bodies in most countries. Regulations generally contain technical requirements to be met by the individual monitoring services (IMS), in order to ensure that the measurements are correct and therefore the dosimetry results are reliable. In some countries, the requirements include or even consist of the accreditation of the service according to the standard ISO/IEC 17025: 'General requirements for the competence of testing and calibration laboratories.' It is a fact that accreditation is a growing trend among European IMS as a way to guarantee confidence in their technical competence. The acceptance of the dosimetry results between countries and their indentation in the respective National Dose Registries is facilitated if laboratories conform to the ISO/IEC 17025 standard. In the framework of the activities of EURADOS (European Radiation Dosimetry Group) working group 2 'Harmonization of Individual Monitoring in Europe' and attending to the concern of many European IMS in the process of accreditation, a guide has been prepared. The purpose was to assist and encourage IMS to apply for accreditation and to share the authors' own experience with the process. The guide intends to be a practical reference for IMS on how to interpret and implement the ISO/IEC 17025 requirements to the specific activity of a personal dosimetry service for external radiation, emphasizing those aspects of special interest. It includes examples from dosimetry laboratories already accredited. The major novelties from a new edition of ISO/IEC 17025: 2017 are also identified in the guide. Finally, the guide aims to assist the auditing process, giving examples of auditor's questions and how to show evidence of compliance. The main findings are presented.
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Laboratórios , Radiometria , Controle de Qualidade , Radiometria/métodos , Europa (Continente) , AcreditaçãoRESUMO
AIMS: The purification and biochemical properties of the 1,4-ß-xylosidase of an oenological yeast were investigated. METHODS AND RESULTS: An ethanol-tolerant 1,4-ß-xylosidase was purified from cultures of a strain of Pichia membranifaciens grown on xylan at 28°C. The enzyme was purified by sequential chromatography on DEAE cellulose and Sephadex G-100. The relative molecular mass of the enzyme was determined to be 50kDa by SDS-PAGE. The activity of 1,4-ß-xylosidase was optimum at pH 6·0 and at 35°C. The activity had a Km of 0·48±0·06mmol l(-1) and a Vmax of 7·4±0·1µmol min(-1)mg(-1) protein for p-nitrophenyl-ß-d-xylopyranoside. CONCLUSIONS: The enzyme characteristics (pH and thermal stability, low inhibition rate by glucose and ethanol tolerance) make this enzyme a good candidate to be used in enzymatic production of xylose and improvement of hemicellulose saccharification for production of bioethanol. SIGNIFICANCE AND IMPACT OF THE STUDY: This study may be useful for assessing the ability of the 1,4-ß-xylosidase from P. membranifaciens to be used in the bioethanol production process.
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Etanol/metabolismo , Glucose/metabolismo , Pichia/enzimologia , Xilose/biossíntese , Xilosidases/biossíntese , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Pichia/metabolismo , Especificidade por Substrato , Xilosidases/isolamento & purificação , Xilosidases/metabolismoRESUMO
OBJECTIVES: This study focuses on the mechanism of interaction of sitamaquine with Leishmania donovani membranes, and its accumulation within the parasites. METHODS: A biomimetic model of the outer layer of a Leishmania plasma membrane was used to examine the interactions of sitamaquine with lipids. The plasma membranes of L. donovani promastigotes were depleted of sterol using cholesterol oxidase, in order to assess the importance of sterols in drug-membrane interactions. Sterols were quantiï¬ed and sitamaquine susceptibility was assessed using the MTT test. Kinetics of sitamaquine accumulation and efflux were measured under different conditions. RESULTS: Sitamaquine interacts first with phospholipid anionic polar head groups and then with phospholipid acyl chains to insert within biological membranes and accumulates rapidly in the Leishmania cytosol according to a sterol-independent process. The rapid sitamaquine efflux observed was related to an energy-dependent mechanism since the intracellular amount of sitamaquine was enhanced three times in the absence of glucose and the efflux was inhibited in energy-depleted conditions. (1)H NMR analysis of motile lipid showed that sitamaquine did not affect lipid trafficking in Leishmania. CONCLUSIONS: We propose that sitamaquine rapidly accumulates in Leishmania by diffusion along an electrical gradient and is concentrated in the cytosol by an energy- and sterol-independent process. The affinity of sitamaquine for membranes was transitory and an energy-dependent efflux was demonstrated, suggesting the presence of an as yet uncharacterized transporter.
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Aminoquinolinas/metabolismo , Antiprotozoários/metabolismo , Membrana Celular/metabolismo , Leishmania donovani/efeitos dos fármacos , Aminoquinolinas/química , Aminoquinolinas/farmacologia , Animais , Antiprotozoários/química , Antiprotozoários/farmacologia , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Membrana Celular/química , Membrana Celular/efeitos dos fármacos , Difusão , Leishmania donovani/metabolismo , Lipídeos de Membrana/química , Lipídeos de Membrana/metabolismo , Fosfolipídeos/metabolismo , Esteróis/metabolismoRESUMO
Tropospheric ozone (O3 ) is considered a major air pollutant having negative effects on plant growth and productivity. Background concentrations are expected to rise in several regions of the world in the next 50 years, affecting plant responses to diseases, thus requiring new management strategies for food production. The effects of elevated O3 on the severity of a bacterial disease, and the effectiveness of a chemical defence inducer, were examined in two cultivars of tomato, Roma and Moneymaker, which present different tolerance to this pollutant. The two cultivars differ in their ability to produce and accumulate reactive oxygen species (ROS) in leaf tissues. Tomato plants were challenged with a strain of Xanthomonas vesicatoria, Xv9, which is pathogenic on tomato. Ozone consistently increased severity of the disease by over 40% in both cultivars. In the more tolerant cultivar, O3 pollution increased disease intensity, even after applying a commercially available product to enhance resistance (acibenzolar-S-methyl, BTH). In the more susceptible cultivar, level of disease attained depended on the oxidative balance that resulted from other stress factors. The antioxidant capacity of the plant at the time of infection was relevant for controlling development of the disease. Our results suggest that development of O3 tolerance in commercial crops might impose a penalty cost in terms of disease management under projected higher O3 concentrations.
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Interações Hospedeiro-Patógeno , Ozônio , Solanum lycopersicum , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/microbiologia , Ozônio/toxicidade , Doenças das Plantas/prevenção & controle , Folhas de Planta/microbiologiaRESUMO
Deconvolution analysis of the thermoluminiscent (TL) glow curves proved to be a good complementary method to characterize the individual glow peaks by fitting their kinetic parameters. In this work, new software has been developed for the automatic deconvolution of TL glow curves, assuming either discrete or continuous distribution of trapping centres. The guess estimation of the kinetic parameters is done automatically and can be manually modified, thus allowing the use of the software for routine, processing a large number of measurements, as well as for research purposes. The equations, the methods and the results of the first test are described in detail. The software has been developed by integrating Fortran code and Visual Studio tools to create a graphic easy-to-use environment and permits to obtain the fitted values for the parameters according to the considered model.
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During the fall of 2005, arugula (Eruca sativa Mill.) plants grown in experimental field plots in Buenos Aires, Argentina presented V-shaped necrotic lesions on leaf margins and blackened veins with broad yellow halos, followed by leaf necrosis. At flowering, 96% of the plants were affected with 27% of the leaves with symptoms. Yellow, round, mucoid, convex, bacterial colonies were isolated from several leaves on yeast dextrose chalk agar. Two strains were further studied. Xanthomonas campestris pv. campestris Xcc8004 was used as a control. Strains were gram negative, rod shaped, strictly aerobic, catalase-positive, oxidase and urease-negative, hydrolyzed starch, gelatine and aesculin, and did not reduce nitrate (2). Pathogenicity was tested by spraying 10 3-week-old arugula plants with either a bacterial suspension (107 CFU/ml) or sterile water. Plants were placed in plastic bags for 72 h after inoculation. All inoculated plants showed necrotic lesions enlarging from the margin of the leaves 7 days after inoculation. No lesions were observed on control plants. On the basis of biochemical characterization (2) and genomic fingerprints generated by BOX-PCR (1), the pathogen was identified as X. campestris pv. campestris. To our knowledge, this is the first report of X. campestris pv. campestris causing black rot on arugula in Argentina. References: (1) J. L. Rademaker et al. Int. J. Syst. Evol. Microbiol. 50:665, 2000. (2) N. W. Schaad et al. Laboratory Guide for Identification of Plant Pathogenic Bacteria. 3rd ed. The American Phytopathological Society, St. Paul, MN, 2001.
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Two different computer vision-based analytical chemistry (CVAC) methods were developed to quantify iron in the commercial pharmaceutical formulations Ferbisol® and Ferro sanol®. The methods involve using a digital camera or a desktop scanner to capture a digital image of a series of Fe2+ standard solutions and the unknown sample upon reaction with o-phenanthroline. The images are processed with appropriate software (e.g., the public domain programme ImageJ, from NIH) to obtain a numerical value (analytical signal) based on colour intensity. The fact that such a value is proportional to the analyte concentration allows one to construct a calibration graph from the standards and interpolate the value for the sample in order to determine its concentration. The results thus obtained were compared with those provided by a spectrophotometric method and the US Pharmacopoeia's recommended method. The differences never exceeded 2%. The two proposed methods are simple and inexpensive; also, they provide an effective instrumental alternative to spectrophotometric methods which can be especially beneficial in those cases where purchasing and maintaining a spectrophotometer is unaffordable.
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Colorimetria/métodos , Compostos Ferrosos/análise , Glicina/análogos & derivados , Ferro/análise , Calibragem , Compostos Ferrosos/química , Glicina/análise , Glicina/química , Ferro/química , Limite de Detecção , Fenantrolinas/química , Fotografação , SoftwareRESUMO
A composted material obtained from forestry wastes and solid phase of pig slurry was evaluated as a substrate component for the production of tomato and lettuce seedlings. Four different substrates were tested: compost (100C), a mixture of 75% compost and 25% peat substrate (75C), a mixture of 50% compost and 50% peat substrate (50C), and peat-based substrate (control). Compost increased the pH of the substrate from 6.3 (control) to 6.9 (100C) but did not affect the electrical conductivity (0.26 and 0.27 mScm(-1), respectively, for control and 100C). Germination and growth of lettuce seedlings were not affected by the substrate type, contrasting with tomato seedlings where the highest growth occurred at 100C substrate. Increasing compost percentage on substrate increased nitrogen, calcium and magnesium availability and, consequently, the concentration of these elements in plant tissues increased. On the contrary, potassium and manganese concentration decreased. Results from the study suggest that the compost studied is a good alternative to peat-based substrates for the production of vegetable seedlings.
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Agricultura Florestal , Eliminação de Resíduos , Plântula/crescimento & desenvolvimento , Solo , Suínos , Animais , Lactuca/química , Lactuca/crescimento & desenvolvimento , Solanum lycopersicum/química , Solanum lycopersicum/crescimento & desenvolvimento , Plântula/química , Eliminação de Resíduos LíquidosRESUMO
We present our initial experience in the treatment of fecal incontinence (FI) with sacral root neuromodulation (SRN) by reporting the results of a prospective study with 26 patients where baseline Wexner-Cleveland scale scores and ability to delay defecation were compared to results after one year with SRN. The initial study of patients included history taking, general examination, anal ultrasonography, and manometry, and a three-week diary of continence and quality of life specific for FI was used. Before SRN the mean baseline Wexner-Cleveland score was 15.00 +/- 1.81, and 62.50% of patients could only delay defecation for less than a minute. After a year with NRS the mean Wexner-Cleveland score was 4.87 +/- 2.54 (p = 0.0031), and 75.01% of patients could delay defecation above fifteen minutes (p = 0.0018). We also describe the surgical technique and its indications, and finally review the various therapeutical options for FI and show our algorithm for this condition. SRN is an effective technique for the treatment of FI in properly selected patients with no response to medical therapies (including biofeedback) or anatomic correction (sphincteroplasty), with efficacy, little morbidity, and a short hospital stay.
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Incontinência Fecal/terapia , Estimulação Elétrica Nervosa Transcutânea , Adulto , Idoso , Algoritmos , Estudos Transversais , Feminino , Humanos , Plexo Lombossacral , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
A new procedure allowing the separate estimation of neutron and gamma dose in mixed radiation fields has been developed in our laboratory. In this communication, a description of the main features of the discrimination procedure and some preliminary results obtained by its use are presented. The procedure is based on the significantly different structure of the glow curve of LiF TLD-600 produced by neutron and gamma radiation. The use of peak resolving numerical methods, sometimes called deconvolution, for the analysis of the glow curves from controlled irradiations at absorbed doses in the range 10-300 mGy with different neutron and gamma proportions, permits to quantify the differences peak by peak, also characterising the well-known neutron quasi-exclusive contribution to the high temperature region, above peak 5. From this study, it was possible to propose a n/gamma TL factor by which the respective doses can be estimated through a simplified analysis, not peak resolving, of the particular features of the glow curves obtained in field measurements. A first set of rather satisfactory results have been obtained by irradiating TLD-600 together with TLD-700 chips using Am-Be sources with different degree of moderation and using lead absorbers to change the gamma component. This component is directly measured by the TLD-700 detectors, allowing the testing of the gamma estimation reached by the discrimination procedure applied to the TLD-600 glow curve.
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Exposição Ambiental/análise , Fluoretos/química , Fluoretos/efeitos da radiação , Compostos de Lítio/química , Compostos de Lítio/efeitos da radiação , Monitoramento de Radiação/instrumentação , Proteção Radiológica/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Raios gama , Internacionalidade , Nêutrons , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
INTRODUCTION: performing anal endosonography in complex fistula-in-ano allows us to design a personalized surgical strategy in each case, thereby improving results. However, there are doubts in the literature as to its utility in recurrent complex fistulas. The aim of this study was to compare the utility of anal ultrasonography in the study of primary versus recurrent complex fistula-in-ano. PATIENTS AND METHOD: prospective study of patients diagnosed and treated for complex fistula-in-ano. Physical examination and anal ultrasonography provided data on primary track, internal opening, horseshoe extension and the presence of secondary tracks or cavities in a protocol designed specifically for the study. These assessments were subsequently contrasted with operative findings. RESULTS: we included 35 patients, 19 (54.3%) with primary complex anal fistulas and 16 (45.7%) with recurrent fistulas. According to the operative findings, fistulas were classified as high transsphincteric in 28 patients (80%), suprasphincteric in 6 (17.1%) and extrasphincteric in one patient (2.9%), with no differences between groups. Physical examination correctly classified 28 of the 35 fistulous tracks, in contrast to the 32 (91.4%) correctly described on ultrasonography (80%). We did not find any statistically significant differences between the primary and the recurrent fistula groups with regard to sensibility, positive predictive value and accuracy of the anal ultrasonography for any of the parameters studied. CONCLUSION: the accuracy of anal ultrasonography does not decrease in recurrent complex fistula-in-ano.
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Canal Anal/diagnóstico por imagem , Fístula Retal/diagnóstico por imagem , Endossonografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Recidiva , Sensibilidade e EspecificidadeRESUMO
In 2008 the European Radiation Dosimetry Group (EURADOS) started a new programme of intercomparisons for individual monitoring services (IMS). The aim was to provide the possibility to IMS in Europe to participate in dosimetry intercomparions with regular time intervals with all types of dosemeter systems that are used routinely to monitor workers for exposure to external radiation. A self-evaluation of the programme shows that, apart from a few problems encountered, the programme can be judged as fit for its purpose. The results of a questionnaire among the participants support this conclusion. The conclusions encourage EURADOS to continue this programme of self-sustained intercomparisons for IMS.
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Doses de Radiação , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Europa (Continente) , Humanos , Cooperação Internacional , Fótons , Controle de Qualidade , Dosímetros de Radiação , Valores de Referência , Inquéritos e QuestionáriosRESUMO
The European Dosimetry Group (EURADOS) first started performing international intercomparisons for whole-body dosemeters for individual monitoring services in 1998. Since 2008, these whole-body intercomparisons have been performed on a regular basis. In this latest intercomparison (IC2014), 96 monitoring services from 35 countries (mostly European) participated with 112 dosimetry systems. Unlike in the previous intercomparisons, the whole registration, communication and data exchange process was handled by a new on-line platform. All dosemeter irradiations were carried out in the Seibersdorf accredited dosimetry laboratory. The irradiation plan consisted of nine irradiation setups with five different photon radiation qualities (S-Cs, S-Co, RQR7, W-80 and W-150) and two different angles of radiation incidence (0° and 60°). The paper describes and analyses the individual results for the personal dose equivalent quantities Hp(10) and if requested, Hp(0.07), for all participating systems and compares these results with the ISO 14146 'trumpet curve' performance criteria. The results show that 100 systems (89 % of all systems) do fulfil the general ISO 14146 performance criteria. This paper gives an overview on the performance of the participating individual monitoring services and the influence of the dosemeter type on the observed response values.
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Doses de Radiação , Dosímetros de Radiação , Monitoramento de Radiação/instrumentação , Proteção Radiológica/métodos , Calibragem , Sistemas Computacionais , Europa (Continente) , Humanos , Luminescência , Fótons , Monitoramento de Radiação/métodos , Proteção Radiológica/instrumentação , Reprodutibilidade dos Testes , Dosimetria Termoluminescente/métodos , Contagem Corporal Total/instrumentaçãoRESUMO
In 2008, the CIEMAT Radiation Dosimetry Service decided to implement a quality management system, in accordance with established requirements, in order to achieve ISO/IEC 17025 accreditation. Although the Service comprises the approved individual monitoring services of both external and internal radiation, this paper is specific to the actions taken by the External Dosimetry Service, including personal and environmental dosimetry laboratories, to gain accreditation and the reflections of 3 y of operational experience as an accredited laboratory.
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Acreditação , Laboratórios/normas , Radiometria/instrumentação , Calibragem , Europa (Continente) , Humanos , Agências Internacionais , Laboratórios/organização & administração , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/normas , Controle de Qualidade , Dosímetros de Radiação , Proteção Radiológica/métodos , Proteção Radiológica/normas , Radiometria/normas , Espanha , Dosimetria Termoluminescente/instrumentação , Dosimetria Termoluminescente/normasRESUMO
BACKGROUND: Osteochondroma is the most common non-malignant tumour of bone, accounting for approximately one third of benign lesions in the skeleton. They often develop around the knee in the distal femur and in the proximal tibia and fibula. They present as a painless slow growing mass during adolescence and have been reported to cause damage to adjacent structures such as blood vessels; arterial damage is more common than venous injury and is usually a result of compression, stretching, and rubbing of the arterial wall. Such lesions include stenosis, thrombosis, and pseudoaneurysm formation possibly causing lower limb claudication or acute limb ischemia. METHODS: An 18 year old male patient with a 4 week history of pain, hematoma, and oedema of the left calf without previous trauma is reported. A computed tomography scan (CT) revealed a large popliteal artery pseudoaneurysm and its close relationship to a protrusion of the proximal tibia. RESULTS: The popliteal artery was repaired by an external saphenous patch and the exostosis was removed. The patient had palpable popliteal and distal pulses after surgery and during the first year follow-up. CONCLUSIONS: Tibial osteochondroma should be considered in the differential diagnosis in young patients, among the potential causes of pseudoaneurysm of the femoral or popliteal artery. Surgical repair should be performed to restore normal blood flow with resection of the exostosis to prevent recurrence.
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This communication describes a recently developed single-exposure neutron spectrometer, based on multiple active thermal neutron detectors located within a moderating sphere, which have been developed jointly by CIEMAT (Spain), INFN (Italy) and Politecnico di Milano (Italy) in the framework of Italian and Spanish collaboration projects. The fabricated prototypes permit to achieve spectrometric resolution with nearly isotropic response for neutron with energies from thermal to 100-200 MeV, thus being able to characterise the complete neutron spectrum in only one exposure by unfolding the measured responses of the detectors. This makes it especially advantageous for characterising neutron fields and workplace monitoring purposes in neutron-producing facilities.