Analysis of particle motion in a micro-fluidic dielectrophoretic device

Interdigitated microelectrodes have found wide applications in manipulating and/or separating biological particles due to their simple structure and easy implementation. Particle behaviors in such interdigitated microelectrode devices are affected by a number of factors, including particle size, electrical potential, chamber geometry and dielectric properties. This paper presents systematical simulation study of particle behaviors in these devices by considering all these influencing factors. A case study is presented to separate different particles using both positive and negative DEP

Plasmon-phonon coupling in large-area graphene dot and antidot arrays

Nanostructured graphene on SiO2 substrates pave the way for enhanced light-matter interactions and explorations of strong plasmon-phonon hybridization in the mid-infrared regime. Unprecedented large-area graphene nanodot and antidot optical arrays are fabricated by nanosphere lithography, with structural control down to the sub-100 nanometer regime. The interaction between graphene plasmon modes and the substrate phonons is experimentally demonstrated and structural control is used to map out the hybridization of plasmons and phonons, showing coupling energies of the order 20 meV. Our findings are further supported by theoretical calculations and numerical simulations.Comment: 7 pages including 6 figures. Supporting information is available upon request to author

Treatment of primary autoimmune cerebellar ataxia with mycophenolate

Immune-mediated ataxias account for a substantial number of sporadic otherwise idiopathic ataxias. Despite some well-characterised entities such as paraneoplastic cerebellar degeneration where diagnostic markers exist, the majority of immune ataxias remained undiagnosed and untreated. We present here our experience in the treatment of suspected primary autoimmune cerebellar ataxia (PACA) using mycophenolate. All patients reported attend the Sheffield Ataxia Centre on a regular basis and had undergone extensive investigations, including genetic testing using next-generation sequencing, with other causes of ataxia excluded. The diagnosis of PACA was strongly suspected based on investigations, pattern of disease progression, and cerebellar involvement. Patients were treated with mycophenolate and monitored using MR spectroscopy of the cerebellar vermis. Thirty patients with PACA are reported here. Of these, 22 received mycophenolate (group 1). The remaining 8 were not on treatment (group 2-control group). Out of the 22 treated patients, 4 underwent serial MR spectroscopy prior to starting treatment and thus were used as controls making the total number of patients in the control group 12. The mean change of the MRS within the vermis (NAA/Cr area ratio) in the treatment group was + 0.144 ± 0.09 (improved) and in the untreated group − 0.155 ± 0.06 (deteriorated). The difference was significant. We also demonstrated a strong correlation between the spectroscopy and the SARA score. We have demonstrated the effectiveness of mycophenolate in the treatment of PACA. The results suggest that immune-mediated ataxias are potentially treatable, and that there is a need for early diagnosis to prevent permanent neurological deficit. The recently published diagnostic criteria for PACA would hopefully aid the diagnosis and treatment of this entity

The existence of solutions for -Laplacian boundary value problems at resonance on the half-line

The concept of collective efficacy, defined as the combination of mutual trust and willingness to act for the common good, has received widespread attention in the field of criminology. Collective efficacy is linked to, among other outcomes, violent crime, disorder, and fear of crime. The concept has been applied to geographical units ranging from below one hundred up to several thousand residents on average. In this paper key informant- and focus group interview transcripts from four Swedish neighborhoods are examined to explore whether different sizes of geographical units of analysis are equally important for collective efficacy. The four studied neighborhoods are divided into micro-neighborhoods (N=12) and micro-places (N=59) for analysis. The results show that neighborhoods appear to be too large to capture the social mechanism of collective efficacy which rather takes place at smaller units of geography. The findings are compared to survey responses on collective efficacy (N=597) which yield an indication in the same direction through comparison of ICC-values and AIC model fit employing unconditional two-level models in HLM 6

A Toy Model for Magnetized Neutrino-Dominated Accretion Flows

In this paper, we present a simplified model for magnetized neutrino-dominated accretion flow (NDAF) in which effect of black hole (BH) spin is taken into account by adopting a set of relativistic correction factor, and the magnetic field is parameterized as \beta, the ratio of the magnetic pressure to the total pressure. It is found that the disc properties are sensitive to the values of the BH spin and \beta, and more energy can be extracted from NDAF for the faster spin and lower \beta.Comment: 4 pages, 3 figures, accepted for publication in Science in China Series

Quantitative Analysis and Comparison Study of [18F]AlF-NOTA-PRGD2, [18F]FPPRGD2 and [68Ga]Ga-NOTA-PRGD2 Using a Reference Tissue Model

With favorable pharmacokinetics and binding affinity for αvβ3 integrin, 18F-labeled dimeric cyclic RGD peptide ([18F]FPPRGD2) has been intensively used as a PET imaging probe for lesion detection and therapy response monitoring. A recently introduced kit formulation method, which uses an 18F-fluoride-aluminum complex labeled RGD tracer ([18F]AlF-NOTA-PRGD2), provides a strategy for simplifying the labeling procedure to facilitate clinical translation. Meanwhile, an easy-to-prepare 68Ga-labeled NOTA-PRGD2 has also been reported to have promising properties for imaging integrin αvβ3. The purpose of this study is to quantitatively compare the pharmacokinetic parameters of [18F]FPPRGD2, [18F]AlF-NOTA-PRGD2, and [68Ga]Ga-NOTA-PRGD2. U87MG tumor-bearing mice underwent 60-min dynamic PET scans following the injection of three tracers. Kinetic parameters were calculated using Logan graphical analysis with reference tissue. Parametric maps were generated using voxel-level modeling. All three compounds showed high binding potential (BpND = k3/k4) in tumor voxels. [18F]AlF-NOTA-PRGD2 showed comparable BpND value (3.75±0.65) with those of [18F]FPPRGD2 (3.39±0.84) and [68Ga]Ga-NOTA-PRGD2 (3.09±0.21) (p>0.05). Little difference was found in volume of distribution (VT) among these three RGD tracers in tumor, liver and muscle. Parametric maps showed similar kinetic parameters for all three tracers. We also demonstrated that the impact of non-specific binding could be eliminated in the kinetic analysis. Consequently, kinetic parameter estimation showed more comparable results among groups than static image analysis. In conclusion, [18F]AlF-NOTA-PRGD2 and [68Ga]Ga-NOTA-PRGD2 have comparable pharmacokinetics and quantitative parameters compared to those of [18F]FPPRGD2. Despite the apparent difference in tumor uptake (%ID/g determined from static images) and clearance pattern, the actual specific binding component extrapolated from kinetic modeling appears to be comparable for all three dimeric RGD tracers

Exploring the Midgut Transcriptome and Brush Border Membrane Vesicle Proteome of the Rice Stem Borer, Chilo suppressalis (Walker)

The rice stem borer, Chilo suppressalis (Walker) (Lepidoptera: Pyralidae), is one of the most detrimental pests affecting rice crops. The use of Bacillus thuringiensis (Bt) toxins has been explored as a means to control this pest, but the potential for C. suppressalis to develop resistance to Bt toxins makes this approach problematic. Few C. suppressalis gene sequences are known, which makes in-depth study of gene function difficult. Herein, we sequenced the midgut transcriptome of the rice stem borer. In total, 37,040 contigs were obtained, with a mean size of 497 bp. As expected, the transcripts of C. suppressalis shared high similarity with arthropod genes. Gene ontology and KEGG analysis were used to classify the gene functions in C. suppressalis. Using the midgut transcriptome data, we conducted a proteome analysis to identify proteins expressed abundantly in the brush border membrane vesicles (BBMV). Of the 100 top abundant proteins that were excised and subjected to mass spectrometry analysis, 74 share high similarity with known proteins. Among these proteins, Western blot analysis showed that Aminopeptidase N and EH domain-containing protein have the binding activities with Bt-toxin Cry1Ac. These data provide invaluable information about the gene sequences of C. suppressalis and the proteins that bind with Cry1Ac