5,408 research outputs found
Preclinical correction of human Fanconi anemia complementation group A bone marrow cells using a safety-modified lentiviral vector.
One of the major hurdles for the development of gene therapy for Fanconi anemia (FA) is the increased sensitivity of FA stem cells to free radical-induced DNA damage during ex vivo culture and manipulation. To minimize this damage, we have developed a brief transduction procedure for lentivirus vector-mediated transduction of hematopoietic progenitor cells from patients with Fanconi anemia complementation group A (FANCA). The lentiviral vector FancA-sW contains the phosphoglycerate kinase promoter, the FANCA cDNA, and a synthetic, safety-modified woodchuck post transcriptional regulatory element (sW). Bone marrow mononuclear cells or purified CD34(+) cells from patients with FANCA were transduced in an overnight culture on recombinant fibronectin peptide CH-296, in low (5%) oxygen, with the reducing agent, N-acetyl-L-cysteine (NAC), and a combination of growth factors, granulocyte colony-stimulating factor (G-CSF), Flt3 ligand, stem cell factor, and thrombopoietin. Transduced cells plated in methylcellulose in hypoxia with NAC showed increased colony formation compared with 21% oxygen without NAC (P<0.03), showed increased resistance to mitomycin C compared with green fluorescent protein (GFP) vector-transduced controls (P<0.007), and increased survival. Thus, combining short transduction and reducing oxidative stress may enhance the viability and engraftment of gene-corrected cells in patients with FANCA
Stable ferromagnetism in p-type carbon-doped ZnO nanoneedles
Author name used in this publication: C. S. Wei2009-2010 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Super-resolving phase measurements with a multi-photon entangled state
Using a linear optical elements and post-selection, we construct an entangled
polarization state of three photons in the same spatial mode. This state is
analogous to a ``photon-number path entangled state'' and can be used for
super-resolving interferometry. Measuring a birefringent phase shift, we
demonstrate two- and three-fold improvements in phase resolution.Comment: 4 pages, 3 figure
Day-ahead allocation of operation reserve in composite power systems with large-scale centralized wind farms
This paper focuses on the day-ahead allocation of operation reserve considering wind power prediction error and network transmission constraints in a composite power system. A two-level model that solves the allocation problem is presented. The upper model allocates operation reserve among subsystems from the economic point of view. In the upper model, transmission constraints of tielines are formulated to represent limited reserve support from the neighboring system due to wind power fluctuation. The lower model evaluates the system on the reserve schedule from the reliability point of view. In the lower model, the reliability evaluation of composite power system is performed by using Monte Carlo simulation in a multi-area system. Wind power prediction errors and tieline constraints are incorporated. The reserve requirements in the upper model are iteratively adjusted by the resulting reliability indices from the lower model. Thus, the reserve allocation is gradually optimized until the system achieves the balance between reliability and economy. A modified two-area reliability test system (RTS) is analyzed to demonstrate the validity of the method.This work was supported by National Natural Science Foundation of China (No. 51277141) and National High Technology Research and Development Program of China (863 Program) (No. 2011AA05A103)
Experimental Quantum Teleportation of a Two-Qubit Composite System
Quantum teleportation, a way to transfer the state of a quantum system from
one location to another, is central to quantum communication and plays an
important role in a number of quantum computation protocols. Previous
experimental demonstrations have been implemented with photonic or ionic
qubits. Very recently long-distance teleportation and open-destination
teleportation have also been realized. Until now, previous experiments have
only been able to teleport single qubits. However, since teleportation of
single qubits is insufficient for a large-scale realization of quantum
communication and computation2-5, teleportation of a composite system
containing two or more qubits has been seen as a long-standing goal in quantum
information science. Here, we present the experimental realization of quantum
teleportation of a two-qubit composite system. In the experiment, we develop
and exploit a six-photon interferometer to teleport an arbitrary polarization
state of two photons. The observed teleportation fidelities for different
initial states are all well beyond the state estimation limit of 0.40 for a
two-qubit system. Not only does our six-photon interferometer provide an
important step towards teleportation of a complex system, it will also enable
future experimental investigations on a number of fundamental quantum
communication and computation protocols such as multi-stage realization of
quantum-relay, fault-tolerant quantum computation, universal quantum
error-correction and one-way quantum computation.Comment: 16pages, 4 figure
Using Technology to Overcome Interprofessional Education Barriers
Common barriers cited for implementing interprofessional education (IPE) and practices are space constraints, scheduling and time conflicts, full curricula, lack of knowledge and skills related to collaborative practice, and accessibility to other disciplines. Due to these significant barriers, IPE necessitates the development of innovative technological teaching modalities, which provide both didactic and experiential approaches.
Using Quality Matters™ standards for designing and evaluating online courses, five interprofessional (IP) online learning activities were developed at a large Midwest academic medical center. The Interprofessional Education Collaborative Expert Panel (IPEC, 2011) rationale for IPE and their four domains for collaborative practice were the framework for the learning activities (LA). Using Blackboard™ as the online platform, LA were inserted in selected courses across programs/disciplines in a timed yet asynchronous event for a period of one week. Each LA time commitment was approximately two hours over a five-day week. Students (n = 187) from six professions (advanced practice nurses, physician assistants, medicine, nutrition, medical lab science, and pharmacy) in nine courses participated. There were 32 interprofessional teams facilitated by six faculty members. Team engagement included viewing videos and short narrated Power Points, and completion of quizzes, case studies, self-reflections or other team assignments and discussions. Feedback from students (n=134) was positive with 70% of students either choosing “agree” or “strongly agree. Participation in the LA increased both their interest (M=2.79/4.0) and knowledge (M=2.78/4.0) of IPE and practice. Twenty-eight students specifically noted strengths of the online format in additional comments.
The online learning activities provide foundational knowledge and skill development for interprofessional collaborative practice in a virtual environment. In conclusion, preliminary data supports that these online LAs are a novel approach to teaching IPE. Utilizing existing university resources, LAs are a cost effect method to teach and overcome barriers to IPE.
Objective 1:
By the end of this presentation, the participants will be able to identify at least three barriers or challenges to interprofessional education and collaborative practice.
Objective 2:
By the end of this presentation, the participants will be able to describe why online learning activities are an effective strategy to overcome barriers to interprofessional education
Microstructural evolution and mechanical properties in Cu48Zr48Al4 bulk metallic glass composites induced by He+ ion irradiation
The irradiation-induced phase transformation and mechanical property stability of the Cu48Zr48Al4 bulk metallic glass composites (BMGCs) were investigated. An obvious structural transformation occurred from the B2-CuZr phase to the B19′-CuZr and the B33-CuZr phases following irradiation, when the dose increased from 2.5 × 1017 ions/cm2 to 1.0 × 1018 ions/cm2. This change was accompanied by the changes of the maximum displacement per atomic (DPA) increasing from 21.5 dpa to 86 dpa. The mean surface roughness increased as the incident dose increased. The local exfoliation occurred at the maximal dose. The changes of mechanical properties were characterized via nanoindentation. The hardness and Young's modulus in the amorphous regions decreased as the dose increased. In contrast, the crystalline regions presented a distinct hardening effect, due to the appearance of the martensitic phases. The macroscopic hardness of the BMGCs obtained by the Vickers indentation instrument was basically unchanged after irradiation. The results suggested that these materials maintained a stable performance, because of the combined effects of hardening and softening. This study could aid the design of novel materials that are subjected to irradiation circumstance.</p
The antitumour activity of 5,6-dimethylxanthenone-4-acetic acid (DMXAA) in TNF receptor-1 knockout mice
5,6-dimethylxanthenone-4-acetic acid, a novel antivascular anticancer drug, has completed Phase I clinical trial. Its actions in mice include tumour necrosis factor induction, serotonin release, tumour blood flow inhibition, and the induction of tumour haemorrhagic necrosis and regression. We have used mice with a targeted disruption of the tumour necrosis factor receptor-1 gene as recipients for the colon 38 carcinoma to determine the role of tumour necrosis factor signalling in the action of 5,6-dimethylxanthenone-4-acetic acid. The pharmacokinetics of 5,6-dimethylxanthenone-4-acetic acid, as well as the degree of induced plasma and tissue tumour necrosis factor, were similar in tumour necrosis factor receptor-1−/− and wild-type mice. However, the maximum tolerated dose of 5,6-dimethylxanthenone-4-acetic acid was considerably higher in tumour necrosis factor receptor-1−/− mice (>100 mg kg−1) than in wild-type mice (27.5 mg kg−1). The antitumour activity of 5,6-dimethylxanthenone-4-acetic acid (25 mg kg−1) was strongly attenuated in tumour necrosis factor receptor-1−/− mice. However, the reduced toxicity in tumour necrosis factor receptor-1−/− mice allowed the demonstration that at a higher dose (50 mg kg−1), 5,6-dimethylxanthenone-4-acetic acid was curative and comparable in effect to that of a lower dose (25 mg kg−1) in wild-type mice. The 5,6-dimethylxanthenone-4-acetic acid -induced rise in plasma 5-hydroxyindoleacetic acid, used to reflect serotonin production in a vascular response, was larger in colon 38 tumour bearing than in non-tumour bearing tumour necrosis factor receptor-1−/− mice, but in each case the response was smaller than the corresponding response in wild-type mice. The results suggest an important role for tumour necrosis factor in mediating both the host toxicity and antitumour activity of 5,6-dimethylxanthenone-4-acetic acid, but also suggest that tumour necrosis factor can be replaced by other vasoactive factors in its antitumour action, an observation of relevance to current clinical studies
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