474 research outputs found
Classification of forefoot plantar pressure distribution in patients with diabetes: a novel perspective for the management of the diabetic foot
Integration of uniform porous shell layers in microfabricated pillar array columns by electrochemical anodization
A micropatterned multielectrode shell for 3D spatiotemporal recording from live cells
Microelectrode arrays (MEAs) have proved to be useful tools for characterizing electrically active cells such as cardiomyocytes and neurons. While there exist a number of integrated electronic chips for recording from small populations or even single cells, they rely primarily on the interface between the cells and 2D flat electrodes. Here, an approach that utilizes residual stressâbased selfâfolding to create individually addressable multielectrode interfaces that wrap around the cell in 3D and function as an electrical shellâlike recording device is described. These devices are optically transparent, allowing for simultaneous fluorescence imaging. Cell viability is maintained during and after electrode wrapping around the cel and chemicals can diffuse into and out of the selfâfolding devices. It is further shown that 3D spatiotemporal recordings are possible and that the action potentials recorded from cultured neonatal rat ventricular cardiomyocytes display significantly higher signalâtoânoise ratios in comparison with signals recorded with planar extracellular electrodes. It is anticipated that this device can provide the foundation for the development of newâgeneration MEAs where dynamic electrodeâcell interfacing and recording substitutes the traditional method using static electrodes
A CMOS Time to Digital Converter IC with 2 Level Analog CAM
A time to charge converter IC with an analog memory unit (TCCAMU) has been designed and fabricated in HP\u27s CMOS 1.2-”m n-well process. The TCCAMU is an event driven system designed for front end data acquisition in high energy physics experiments. The chip includes a time to charge converter, analog Level 1 and Level 2 associative memories for input pipelining and data filtering, and an A/D converter. The intervals measured and digitized range from 8-24 ns. Testing of the fabricated chip resulted in an LSB width of 107 ps, a typical differential nonlinearity of \u3c 35 ps, and a typical integral nonlinearity of \u3c 200 ps. The average power dissipation is 8.28 mW per channel. By counting the reference clock, a time resolution of 107 ps over ~ 1 s range could be realized
Positron surface state as a spectroscopic probe for characterizing surfaces of topological insulator materials
Topological insulators are attracting considerable interest due to their potential for technological applications and as platforms for exploring wide-ranging fundamental science questions. In order to exploit, fine-tune, control, and manipulate the topological surface states, spectroscopic tools which can effectively probe their properties are of key importance. Here, we demonstrate that positrons provide a sensitive probe for topological states and that the associated annihilation spectrum provides a technique for characterizing these states. Firm experimental evidence for the existence of a positron surface state near Bi2Te2Se with a binding energy of Eb=2.7±0.2eV is presented and is confirmed by first-principles calculations. Additionally, the simulations predict a significant signal originating from annihilation with the topological surface states and show the feasibility to detect their spin texture through the use of spin-polarized positron beams.Academy of Finland (Projects No. 285809)Academy of Finland (Projects No. 293932)United States. Department of Energy. Office of Basic Energy Sciences (Grant No. DE-FG02- 07ER4635)United States. Department of Energy (Grant No. DE-AC02-05CH11231)National Science Foundation (U.S.) (Grants No. DMR-MRI-1338130)National Science Foundation (U.S.) (Grants No. DMR-1508719)National Science Foundation (U.S.) (Grants No. DMR-1231319)National Science Foundation (U.S.) (DMR-1207469)United States. Office of Naval Research (Grant No. N00014-13-1-0301)Laboratoire de physique theÌorique. EÌcole Normale SupeÌrieule. International Centre for Fundamental Physics (Grant No. ANR-10-LABX-0010/ANR- 10-IDEX-0001-02 PSL
Sexually dimorphic tibia shape is linked to natural osteoarthritis in STR/Ort mice
Human osteoarthritis (OA) is detected only at late stages. Male STR/Ort mice develop knee OA spontaneously with known longitudinal trajectory, offering scope to identify OA predisposing factors. We exploit the lack of overt OA in female STR/Ort and in both sexes of parental, control CBA mice to explore whether early divergence in tibial bone mass or shape are linked to emergent OA
Nature of the positron state in CdSe quantum dots
Previous studies have shown that positron-annihilation spectroscopy is a
highly sensitive probe of the electronic structure and surface composition of
ligand-capped semiconductor Quantum Dots (QDs) embedded in thin films. Nature
of the associated positron state, however, whether the positron is confined
inside the QDs or localized at their surfaces, has so far remained unresolved.
Our positron-annihilation lifetime spectroscopy (PALS) studies of CdSe QDs
reveal the presence of a strong lifetime component in the narrow range of
358-371 ps, indicating abundant trapping and annihilation of positrons at the
surfaces of the QDs. Furthermore, our ab-initio calculations of the positron
wave function and lifetime employing a recent formulation of the Weighted
Density Approximation (WDA) demonstrate the presence of a positron surface
state and predict positron lifetimes close to experimental values. Our study
thus resolves the longstanding question regarding the nature of the positron
state in semiconductor QDs, and opens the way to extract quantitative
information on surface composition and ligand-surface interactions of colloidal
semiconductor QDs through highly sensitive positron-annihilation techniques.Comment: 14 pages, 3 figure
Diagnostic Value of the Hemopexin N-Glycan Profile in Hepatocellular Carcinoma Patients
What is new in surgical treatment of vesicoureteric reflux?
In addition to conventional open surgery and endoscopic techniques, laparoscopic correction of vesicoureteric reflux, sometimes even robot-assisted, is becoming an alternative surgical treatment modality for this condition in a number of centres around the world. At least for a subgroup of patients laparoscopists are trying to develop new techniques in an effort to combine the best of both worlds: the minimal invasiveness of the STING and the same lasting effectiveness as in open surgery. The efficacy and potential advantages or disadvantages of these techniques are still under investigation. The different laparoscopic techniques and available data are presented
IL-4R alpha blockade by dupilumab decreases Staphylococcus aureus colonization and increases microbial diversity in atopic dermatitis
Dupilumab is a fully human antibody to interleukin-4 receptor alpha that improves the signs and symptoms of moderate to severe atopic dermatitis (AD). To determine the effects of dupilumab on Staphylococcus aureus colonization and microbial diversity on the skin, bacterial DNA was analyzed from swabs collected from lesional and nonlesional skin in a double-blind, placebo-controlled study of 54 patients with moderate to severe AD randomized (1:1) and treated with either dupilumab (200 mg weekly) or placebo for 16 weeks. Microbial diversity and relative abundance of Staphylococcus were assessed by DNA sequencing of 16S ribosomal RNA, and absolute S. aureus abundance was measured by quantitative PCR. Before treatment, lesional skin had lower microbial diversity and higher overall abundance of S. aureus than nonlesional skin. During dupilumab treatment, microbial diversity increased and the abundance of S. aureus decreased. Pronounced changes were seen in nonlesional and lesional skin. Decreased S. aureus abundance during dupilumab treatment correlated with clinical improvement of AD and biomarkers of type 2 immunity. We conclude that clinical improvement of AD that is mediated by interleukin-4 receptor alpha inhibition and the subsequent suppression of type 2 inflammation is correlated with increased microbial diversity and reduced abundance of S. aureus
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