49 research outputs found

    Plasmonic Waveguide-Integrated Nanowire Laser

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    Next-generation optoelectronic devices and photonic circuitry will have to incorporate on-chip compatible nanolaser sources. Semiconductor nanowire lasers have emerged as strong candidates for integrated systems with applications ranging from ultrasensitive sensing to data communication technologies. Despite significant advances in their fundamental aspects, the integration within scalable photonic circuitry remains challenging. Here we report on the realization of hybrid photonic devices consisting of nanowire lasers integrated with wafer-scale lithographically designed V-groove plasmonic waveguides. We present experimental evidence of the lasing emission and coupling into the propagating modes of the V-grooves, enabling on-chip routing of coherent and sub diffraction confined light with room temperature operation. Theoretical considerations suggest that the observed lasing is enabled by a waveguide hybrid photonic-plasmonic mode. This work represents a major advance toward the realization of application-oriented photonic circuits with integrated nanolaser sources

    Bottom-up engineering of InAs at the nanoscale: From V-shaped nanomembranes to nanowires

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    The ability to rationally tune the morphology of nanostructures is a fundamental milestone in nanoscale engineering. In particular, the possibility to switch between different shapes within the same material system represents a further step in the development of complex nanoscale devices and it increases the potential of nanostructures in practical applications. We recently reported a new form of InAs nanostructures growing epitaxially on Si substrates as vertical V-shaped membranes. Here we demonstrate the possibility of modifying the shape of these nanomembranes and turning them into nanowires by modulating the surface roughness of the substrate by varying the surface treatment. We show that the growth of nanomembranes is favored on smooth surfaces. Conversely rough surfaces enhance the growth of nanowires. We also shove that the V/III ratio plays a key role in determining the absolute yield, i.e. how many nanostructures form during growth. These results envisage a new degree of freedom in the engineering of bottom up nanostructures and contribute to the achievement of nanostructure networks. (C) 2015 Elsevier B.V. All rights reserved

    Prevalence and correlates of inadequate glycaemic control: results from a nationwide survey in 6,671 adults with diabetes in Brazil

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    Diabetes is a significant public health burden on the basis of its increased incidence, morbidity, and mortality. This study aimed to estimate the prevalence of inadequate glycaemic control and its correlates in a large multicentre survey of Brazilian patients with diabetes. A cross-sectional study was conducted in a consecutive sample of patients aged 18 years or older with either type 1 or type 2 diabetes, attending health centres located in ten large cities in Brazil (response rate = 84%). Information about diabetes, current medications, complications, diet, and satisfaction with treatment were obtained by trained interviewers, using a standardized questionnaire. Glycated haemoglobin (HbA1c) was measured by high-performance liquid chromatography in a central laboratory. Patients with HbA1c ≄ 7 were considered to have inadequate glycaemic control. Overall 6,701 patients were surveyed, 979 (15%) with type 1 and 5,692 (85%) with type 2 diabetes. The prevalence of inadequate glycaemic control was 76%. Poor glycaemic control was more common in patients with type 1 diabetes (90%) than in those with type 2 (73%), P < 0.001. Characteristics significantly associated with improved glycaemic control included: fewer years of diabetes duration, multi professional care, participation in a diabetes health education program, and satisfaction with current diabetes treatment. Despite increased awareness of the benefits of tight glycaemic control, we found that few diabetic patients in Brazil met recommended glycaemic control targets. This may contribute to increased rates of diabetic complications, which may impact health care costs. Our data support the public health message of implementation of early, aggressive management of diabetes

    A SARS-CoV-2 protein interaction map reveals targets for drug repurposing

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    The novel coronavirus SARS-CoV-2, the causative agent of COVID-19 respiratory disease, has infected over 2.3 million people, killed over 160,000, and caused worldwide social and economic disruption1,2. There are currently no antiviral drugs with proven clinical efficacy, nor are there vaccines for its prevention, and these efforts are hampered by limited knowledge of the molecular details of SARS-CoV-2 infection. To address this, we cloned, tagged and expressed 26 of the 29 SARS-CoV-2 proteins in human cells and identified the human proteins physically associated with each using affinity-purification mass spectrometry (AP-MS), identifying 332 high-confidence SARS-CoV-2-human protein-protein interactions (PPIs). Among these, we identify 66 druggable human proteins or host factors targeted by 69 compounds (29 FDA-approved drugs, 12 drugs in clinical trials, and 28 preclinical compounds). Screening a subset of these in multiple viral assays identified two sets of pharmacological agents that displayed antiviral activity: inhibitors of mRNA translation and predicted regulators of the Sigma1 and Sigma2 receptors. Further studies of these host factor targeting agents, including their combination with drugs that directly target viral enzymes, could lead to a therapeutic regimen to treat COVID-19

    Infantile polymyositis with normal serum creatine kinase level

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    WOS: A1997WX81600012PubMed ID: 9071493A 30-month-old boy who has been suffering progressive proximal muscle weakness and severe atrophy in shoulder and hip muscles from 11 months of age had prominent perivascular inflammatory cellular infiltration in his muscle biopsy and myopathic EMG changes. But his serum creatine kinase (CK) levels were repeatedly found to be within normal ranges. Oral prednisolone therapy (2 mg/kg/d) brought a complete recovery of muscle power and normalization of EMG and muscle biopsy findings. This report provides an additional support that the cases of infantile polymyositis with normal serum CK levels may respond well to steroid therapy. (C) 1997 Elsevier Science B.V

    Oxcarbazepine in the treatment of childhood epilepsy

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    WOS: 000181959800006PubMed ID: 12657418In this study, oxcarbazepine was began as monotherapy to evaluate the efficacy and safety of the drug. Forty-two patients (19 females, 23 males) with partial or generalized epilepsy more than 4 years of age were included (mean age, 11.9 +/- 3.4 years). The mean age at epilepsy onset 8.9 4 years. Complete blood count, liver function tests, electrolytes, lipid levels, electrocardiography, electroencephalography, and magnetic resonance imaging were performed in all patients. Oxcarbazepine dose was begun at 10 mg/kg/day twice daily and increased to 30 mg/kg/day at the end of the second week. Patients with inadequate seizure control even with the dose of 45 mg/kg/day or intolerable side effects were excluded. Intolerable headache and leukopenia led to discontinuation of the drug in two patients. At the sixth month, 35 of the patients (87.5%) were seizure free (91.7% of the generalized epilepsy patients and 81.2% of the partial epilepsy patients). The most frequent tolerable side effect was drowsiness in 12 patients. As a result, we found oxcarbazepine safe and effective in children with either generalized or partial epilepsy. (C) 2003 by Elsevier Science Inc. All rights reserved

    Quantitative microfluidic fluorescence microscopy to study vaso-occlusion in sickle cell disease

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    Photograph of a scene at Turner Falls

    Glucose tolerance tests in the singleton and twin pregnancy

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    Objective. Gestational diabetes mellitus (GDM) is defined as glucose intolerance that is detected for the first time during pregnancy. Normal pregnancy induces insulin resistance through the diabetogenic effects of placental hormones. Glucose tolerance test results in twin and singleton pregnancies were compared in this study. Subjects and Methods. A total of 360 pregnant women were studied. 200 women (mean age 31.60±2.10 yr) had singleton pregnancies (Group I) and 160 women (mean age 28.20±2.70 yr) had twin pregnancies (Group II). 50- g, 1- hour glucose tolerance test was conducted on the first prenatal visit. An abnormal glucose screen defined as glucose &gt; 140 mg/dL was followed by a 100g, 3-hour glucose tolerance test. Gestational diabetes was defined as the presence of two or more abnormal values during the 3-hour test. Results. Gestational diabetes was found in 4 of the 200 (2%) singleton pregnant women and 8 of the 160 (5%) twin pregnant women. Group I (Singleton) was further divided into two subgroups according to whether the 1-hr plasma glucose level was &lt; 140 mg/dl (Group Ia) or &gt;140 mg/dL (Group Ib). Likewise, Group II pregnancies was also divided into two subgoups on the same basis. Mean screening test glucose levels were found to be 127.8±14.94 mg/dL in Group Ia and 150.8 ± 18.1 mg/dL in Group Ib women. Mean screening test glucose levels of Group IIa subjects was 92.80 ± 18.30 mg/dL while that of Group IIb subjects was 154.8 ± 27.0 mg/dL. Mean 1st h glucose levels of 100-g glucose tolerance test was found to be 131.4 ± 32.58 mg/dL in Group I, and 112.5 ± 39.6 mg/dL in Group II. Mean 2nd h glucose tolerance test values were 133.2 ± 28.8 mg/dL in Group I and 100.6±28.8 mg/dL in Group II. Mean 3rd h glucose tolerance test values were 107.6 ± 23.58 mg/dl in Group I and 72±16.9 mg/dL in Group II. Conclusion: Glucose screening results and 100-g, 3- hour glucose tolerance test values have been found to be lower in twin pregnancies than in singleton pregnancies. Therefore, we suggest that these findings be taken into account in developing diagnostic criteria for gestational diabetes in twin or more pregnancies
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