377 research outputs found

    Sol–gel synthesis, X-ray photoelectron spectroscopy and electrical conductivity of Co-doped (La, Sr)(Ga, Mg)O3−δ perovskites

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    La0.8Sr0.2Ga0.8Mg0.2−xCoxO3−δ (LSGMC) powders containing different amounts of Co (x = 0.05 and 0.085) were prepared by a citrate sol–gel method. The powders were used to prepare highly phase-pure LSGMC sintered pellets with controlled composition and fractional densities larger than 95%. For the first time, LSGMC materials were subjected to X-ray photoelectron spectroscopy (XPS) characterization. XPS data confirmed the presence of the dopants in the material and allowed to identify two different chemical states for Sr2+ and oxygen, both related to the oxygen-deficient perovskite structure of LSGMC. The conductivity of LSGMC sintered pellets containing different amounts of Co ions in the B sites of the perovskite lattice was assessed by electrochemical impedance spectroscopy (EIS) in the 250–750 °C temperature range. Conductivity values and apparent activation energies were in good agreement with previously published data referring to materials with same composition, but prepared by solid-state route. Therefore, the physicochemical and electrochemical characterization clearly demonstrated the ability of sol–gel methods to produce high-purity Co-doped LSGM perovskites, which represent promising solid electrolytes for intermediate-temperature SOFCs

    Results on pre-series production and QA/QC tests of the double-ends readout panels of the new layer of trigger chambers for the ATLAS muon spectrometer phase 2 upgrade

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    In view of High Luminosity LHC upgrade, the ATLAS experiment will add a new layer of Resistive Plate Chambers (RPC) trigger chambers into the barrel muon spectrometer. These next-generation RPC chambers will use a 1 mm gap and a single type of readout strips coupled to front-end electronics capable of providing both coordinates in the detector plane. The procedures for assembling the readout panels and the results of Quality Assurance and Quality Control (QA/QC) tests on the pre-series panels is reported here

    Personal, non-commercial use only

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    ABSTRACT. Objective. To investigate by high frequency grey-scale ultrasonography (US) and power Doppler sonography (PDS) the modality and frequency of involvement of the Achilles tendon and plantar fascia in chondrocalcinosis (CC), and to correlate these findings with clinical complaints and radiographic evidence. Methods. The heels of 57 consecutive patients with CC were evaluated by US, PDS, and radiography. One control group of 50 consecutive patients with osteoarthritis (OA) without signs of CC was studied in the same way. A second control group of 50 healthy subjects underwent only US/PDS examination. All subjects also underwent clinical assessment. Results. US revealed Achilles tendon calcifications in 57.9% of those with CC, but none in the control groups. Plantar fascia calcifications were observed in 15.8% of CC and in 2% of OA cases, but not in healthy controls. US showed no significant difference in postero-inferior and inferior calcaneal enthesophytosis between subjects with CC (59.6% and 61.4%, respectively) and those with OA (46% and 44%, respectively). Such alterations were also present, in lower percentages, in the healthy controls. Posterior and inferior calcaneal erosions were absent in all groups. Achilles enthesopathy was found in 22.8% of patients with CC (14.9% of heels, with vascular signals in 11.4% of heels on PDS). Deep retrocalcaneal bursitis was found in 10.5% of patients with CC (7% of heels, with vascular signals in 5.2% of heels on PDS). Plantar fasciitis was found in 40.3% of patients with CC (36% of heels, with vascular signals in 2.6% of heels on PDS) and in 14% of OA patients, but not in healthy controls. No significant correlation was found between talalgia or sex of patients and presence of calcifications. A significant correlation was observed between talalgia and Achilles enthesopathy (r = 0.78, p < 0.0001), deep retrocalcaneal bursitis (r = 0.7, p < 0.0001), and plantar fasciitis (r = 0.31, p < 0.001). A significant correlation between talalgia and vascular signals on PDS was observed in Achilles enthesopathy (r = 0.91, p < 0.0001) and deep retrocalcaneal bursitis (r = 0.65, p < 0.0001). The presence of vascular signals on PDS was significantly associated with the presence of tendinous and bursal grey-scale US alterations. Achilles tendon calcifications were 39% sensitive, 100% specific, and 77% accurate for the presence of CC, whereas plantar fascia calcifications were 15% sensitive, 98% specific, and 54% accurate. Excellent agreement was found between US and radiography in detecting Achilles tendon calcifications (k = 0.86), plantar fascia calcifications (k = 0.77), postero-inferior enthesophytosis (k = 0.90), and inferior enthesophytosis (k = 0.83). Chondrocalcinosis (CC) is an arthropathy generally caused by deposit of calcium pyrophosphate-dihydrate (CPPD) microcrystals in the joints and in the tendons 1,2 . In CPPD crystal deposition disease typical linear calcifications can be found in fibrocartilage, especially in the knee menisci, carpus triangular ligament, symphysis pubis, and in hyaline articular cartilage, especially in the knee 1,2 . Calcifications in tendons have been described in previous radiological reports 3-9 : Achilles tendon, gastrocnemius tendon, hip adductors, and quadriceps tendon were the sites primarily involved. Conclusio

    Uropathogenic Escherichia coli (UPEC) strains may carry virulence properties of diarrhoeagenic E-coli

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    To analyze whether Escherichia coli strains that cause urinary tract infections (UPEC) share virulence characteristics with the diarrheagenic E. coli (DEC) pathotypes and to recognize their genetic diversity, 225 UPEC strains were examined for the presence of various properties of DEC and UPEC (type of interaction with HeLa cells, serogroups and presence of 30 virulence genes). No correlation between adherence patterns and serogroups was observed. Forty-five serogroups were found, but 64% of the strains belonged to one of the 12 serogroups (O1, O2, O4, O6, O7, O14, O15, O18, O21, O25, O75, and O175) and carried UPEC virulence genes (pap, hly, aer, sfa, cnf). the DEC genes found were: aap, aatA, aggC, agg3C, aggR, astA, eae, ehly, iha, irp2, lpfA(O113), pet, pic, pilS, and shf. Sixteen strains presented aggregative adherence and/or the aatA sequence, which are characteristics of enteroaggregative E. coli (EAEC), one of the DEC pathotypes. in summary, certain UPEC strains may carry DEC virulence properties, mostly associated to the EAEC pathotype. This finding raises the possibility that at least some faecal EAEC strains might represent potential uropathogens. Alternatively, certain UPEC strains may have acquired EAEC properties, becoming a potential cause of diarrhoea.Universidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Immunol & Parasitol, BR-04023062 São Paulo, BrazilUniv Santiago de Compostela, Fac Vet, Dept Microbiol & Parasitol, Lab Referencia E Coli, Lugo, SpainUniversidade Federal de São Paulo, Lab Cent Hosp São Paulo, São Paulo, BrazilInst Butantan, Bacteriol Lab, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Immunol & Parasitol, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, Lab Cent Hosp São Paulo, São Paulo, BrazilWeb of Scienc

    Mystery Solved: The Identification of the Two Missing Romanov Children Using DNA Analysis

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    One of the greatest mysteries for most of the twentieth century was the fate of the Romanov family, the last Russian monarchy. Following the abdication of Tsar Nicholas II, he and his wife, Alexandra, and their five children were eventually exiled to the city of Yekaterinburg. The family, along with four loyal members of their staff, was held captive by members of the Ural Soviet. According to historical reports, in the early morning hours of July 17, 1918 the entire family along with four loyal members of their staff was executed by a firing squad. After a failed attempt to dispose of the remains in an abandoned mine shaft, the bodies were transported to an open field only a few kilometers from the mine shaft. Nine members of the group were buried in one mass grave while two of the children were buried in a separate grave. With the official discovery of the larger mass grave in 1991, and subsequent DNA testing to confirm the identities of the Tsar, the Tsarina, and three of their daughters – doubt persisted that these remains were in fact those of the Romanov family. In the summer of 2007, a group of amateur archeologists discovered a collection of remains from the second grave approximately 70 meters from the larger grave. We report forensic DNA testing on the remains discovered in 2007 using mitochondrial DNA (mtDNA), autosomal STR, and Y- STR testing. Combined with additional DNA testing of material from the 1991 grave, we have virtually irrefutable evidence that the two individuals recovered from the 2007 grave are the two missing children of the Romanov family: the Tsarevich Alexei and one of his sisters

    Stuttered swallowing: Electric stimulation of the right insula interferes with water swallowing. A case report

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    <p>Abstract</p> <p>Background</p> <p>Various functional resonance imaging, magnetoencephalographic and lesion studies suggest the involvement of the insular cortex in the control of swallowing. However, the exact location of insular activation during swallowing and its functional significance remain unclear.</p> <p>Case presentation</p> <p>Invasive electroencephalographic monitoring was performed in a 24-year-old man with medically intractable stereotyped nocturnal hypermotor seizures due to a ganglioglioma. During stimulation of the right inferior posterior insular cortex with depth electrodes the patient spontaneously reported a perception of a "stutter in swallowing". Stimulation of the inferior posterior insular cortex at highest intensity (4 mA) was also associated with irregular and delayed swallows. Swallowing was not impaired during stimulation of the superior posterior insular cortex, regardless of stimulation intensity.</p> <p>Conclusions</p> <p>These results indicate that the right inferior posterior insular cortex is involved in the neural circuitry underlying the control of swallowing.</p

    The real risks of steroid injection for plantar fasciitis, with a review of conservative therapies

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    This article presents a review of conservative therapies for plantar fasciitis pain reduction with a discussion of steroid therapy risks. The therapies reviewed include orthoses, stretching, extracorporeal shockwave, BTX-A, and corticosteroid injection/iontophoresis. These modes were included based on the availability of double blinded randomized controlled trials. We noted the following findings. Orthoses, regardless of type, can improve pain levels. Plantar stretching shows limited short-term benefit (1 month), but can reflect significant long-term improvement (10 months). Extracorporeal shockwave therapy shows equivocal benefit with some studies showing significant improvement and others showing none. Although BTX-A injections were the least studied, significant pain improvement was demonstrated in the short and long term. Steroid injection/iontophoresis showed significant improvement in the short term (1 month). Steroid therapy, when coupled with plantar stretching, can provide efficacious pain relief; however, steroid injections should be combined with ultrasound monitoring to reduce complications

    Disfagia orofaríngea neurogênica: análise de protocolos de videofluoroscopia brasileiros e norte-americanos

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    Resumo: Este artigo tem por objetivo analisar e comparar o uso de protocolos brasileiros e norte-americanos para videofluoroscopia da deglutição em pacientes com histórico de acidente vascular encefálico. Trata-se de uma revisão bibliográfica de artigos brasileiros e norte-americanos. Foram selecionados artigos com descrição de procedimentos para videofluoroscopia da deglutição em sujeitos que sofreram acidente vascular encefálico, publicados entre 2003 e 2013. Os procedimentos descritos para realização de videofluoroscopias foram analisados de forma quantitativa e qualitativa. Consideraram-se as variáveis: posicionamento para o exame, consistências e quantidades de oferta de bolo, tipos de utensílios e utilização de protocolos Foram encontrados 16 artigos que atenderam aos critérios supracitados, sendo nove (56,25%) norte-americanos e sete (43,75%) brasileiros. Observou-se que quatro dos estudos nacionais (57,14%) não relatam as quantidades oferecidas, enquanto todos os artigos norte-americanos detalharam as quantidades, que variaram entre 2 e 15 mL; os tipos de alimento e suas consistências foram detalhadas em todos os estudos nacionais e norte-americanos, porém os nacionais o fizeram de forma genérica, sem identificação dos alimentos. Quanto à posição do paciente durante o exame, 57,14% dos artigos nacionais não relataram e todos os artigos norte-americanos o fizeram. Os utensílios para oferta do bolo são citados em 55,55% dos artigos norte-americanos e em apenas 14,28 % dos nacionais. Quanto à utilização de protocolos para avaliação 33% dos estudos norte-americanos não os citam, comparados aos 71,42% dos nacionais. Observou-se a necessidade de padronização dos procedimentos e terminologias utilizadas na videofluoroscopia da deglutição, de modo a facilitar a intercompreensão e reprodutibilidade dos estudos
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