63 research outputs found
Orbital Characters Determined from Fermi Surface Intensity Patterns using Angle-Resolved Photoemission Spectroscopy
In order to determine the orbital characters on the various Fermi surface
pockets of the Fe-based superconductors BaKFeAs and
FeSeTe, we introduce a method to calculate photoemission
matrix elements. We compare our simulations to experimental data obtained with
various experimental configurations of beam orientation and light polarization.
We show that the photoemission intensity patterns revealed from angle-resolved
photoemission spectroscopy measurements of Fermi surface mappings and
energy-momentum plots along high-symmetry lines exhibit asymmetries carrying
precious information on the nature of the states probed, information that is
destroyed after the data symmetrization process often performed in the analysis
of angle-resolved photoemission spectroscopy data. Our simulations are
consistent with Fermi surfaces originating mainly from the ,
and orbitals in these materials.Comment: 16 pages, 9 figures. Figures modified, typos corrected, appendix
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The kinetics of polyethylenimine-mediated transfection in suspension cultures of Chinese hamster ovary cells
The kinetics of polyethylenimine (PEI)-mediated gene transfer at early times after transfection of Chinese hamster ovary (CHO) cell in suspension were investigated using a novel in vitro assay. Addition of an excess of competitor DNA to the culture medium at various times after the initiation of transfection inhibited further cellular uptake of PEI-DNA particles. Using this approach, a constant rate of particle uptake was observed during the first 60 min of transfection at a PEI:DNA ratio of 2:1 (w/w) and a cell density of 2 x 10(6) cells/ml under serum-free conditions. The uptake rate declined considerably during the next 2 h of transfection. Both the rate and the level of PEI-DNA uptake in serum-free minimal medium were found to be dependent on the PEI-DNA ratio, the cell density at the time of transfection, and the extent of particle aggregation. These studies of the early phase of PEI-mediated transfection are expected to lead to further opportunities for optimization of gene transfer to suspension cultures of mammalian cells for the purpose of large-scale transient recombinant protein production
An Organic D-pi-A Dye for Record Efficiency Solid-State Sensitized Heterojunction Solar Cells
The high molar absorption coefficient organic D-pi-A dye C220 exhibits more than 6% certified electric power conversion efficiency at AM 1.5G solar irradiation (100 mW cm(-2)) in a solid-state dye sensitized solar cell using 2,2',7,7'-tetrakis(N,N-dimethoxyphenylamine)-9,9'-spirobi-fluorene (Spiro-MeOTAD) as the organic hole transporting material. This contributes to a new record (6.08% by NREL) for this type of sensitized heterojunction photovoltaic device. Efficient charge generation is proved by incident photon-to-current conversion efficiency spectra. Transient photovoltage and photocurrent decay measurements showed that the enhanced performance achieved with C220 partially stems from the high charge collection efficiency over a wide potential range
Procalcitonin and C-Reactive Protein for Invasive Bacterial Pneumonia Diagnosis among Children in Mozambique, a Malaria-Endemic Area
Background: Pneumonia is the major cause of mortality and morbidity in children worldwide. Procalcitonin (PCT) and C-reactive protein (CRP) are used in developed countries to differentiate between viral and bacterial causes of pneumonia. Validity of these markers needs to be further explored in Africa. Methodology and Principal Findings: We assessed the utility of PCT and CRP to differentiate viral from invasive bacterial pneumonia in children <5 years hospitalized with clinical severe pneumonia (CSP) in rural Mozambique, a malaria-endemic area with high HIV prevalence. Prognostic capacity of these markers was also evaluated. Out of 835 children with CSP, 87 fulfilled definition of viral pneumonia and 89 of invasive bacterial pneumonia. In absence of malaria parasites, levels of PCT and CRP were lower in the viral group when compared to the invasive bacterial one (PCT: median = 0.21 versus 8.31 ng/ml, p<0.001; CRP: 18.3 vs. 185.35 mg/l, p<0.001). However, in presence of malaria parasites distribution between clinical groups overlapped (PCT: median = 23.1 vs. 21.75 ng/ml, p = 0.825; CRP: median = 96.8 vs. 217.4 mg/l, p = 0.052). None of the two markers could predict mortality. Conclusions: Presence of malaria parasites should be taken into consideration, either for clinical or epidemiological purposes, if using PCT or CRP to differentiate viral from invasive bacterial pneumonia in malaria-endemic areas
Bacterial Causes of Empyema in Children, Australia, 2007–2009
Most infections were caused by non–7-valent pneumococcal conjugate vaccine serotypes
An Organic D-π-A Dye for Record Efficiency Solid-State Sensitized Heterojunction Solar Cells
Neurodevelopment outcome of newborns with cerebral subependymal pseudocysts at 18 and 46 months: a prospective study
Neurodevelopment outcome of newborns with cerebral subependymal pseudocysts at 18 and 46 months: a prospective study.
OBJECTIVES: Subependymal pseudocysts (SEPC) are cerebral periventricular cysts located on the floor of the lateral ventricle and result from regression of the germinal matrix. They are increasingly diagnosed on neonatal cranial ultrasound. While associated pathologies are reported, information about long-term prognosis is missing, and we aimed to investigate long-term follow-up of these patients.
STUDY DESIGN: Newborns diagnosed with SEPC were enrolled for follow-up. Neurodevelopment outcome was assessed at 6, 18 and 46 months of age.
RESULTS: 74 newborns were recruited: we found a high rate of antenatal events (63%), premature infants (66% <37 weeks, 31% <32 weeks) and twins (30%). MRI was performed in 31 patients, and cystic periventricular leukomalacia (c-PVL) was primarily falsely diagnosed in 9 of them. Underlying disease was diagnosed in 17 patients, 8 with congenital cytomegalovirus (CMV) infection, 5 with genetic and 4 with metabolic disease. Neurological examination (NE) at birth was normal for patients with SEPCs and no underlying disease, except one. Mean Developmental Quotient and IQ of these patients was 98.2 (±9.6SD; range 77-121), 94.6 (±14.2SD; 71-120) and 99.6 (±12.3SD; 76-120) at 6, 18 and 46 months of age, respectively, with no differences between the subtypes of SEPC. A subset analysis showed no outcome differences between preterm infants with or without SEPC, or between preterm of <32 GA and ≥32 GA.
CONCLUSIONS: Neurodevelopment of newborns with SEPC was normal when no underlying disease was present. This study suggests that if NE is normal at birth and congenital CMV infection can be excluded, then no further investigations are needed. Moreover, it is crucial to differentiate SEPC from c-PVL which carries a poor prognosis
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