2,103 research outputs found
Investigating the Impact of IT Ambidexterity on Digital Innovation Capability
Digital innovation is characterized by generativity, in which digital technologies act upon other technologies, products, services, or processes to generate innovations. Because of generativity, digital innovation should be understood as involving multiple events that could be associated with changes in the process and outcome of IS and business activities. Drawing upon Swanson’s (1994) tri-core model of IS innovation, this study argues that digital innovation could entail innovative IS activities in the functional IS, business administration, and business technology areas. Since these areas rely differently upon innovative digital technologies, this study suggests that organizations should pursue IT exploitation and IT exploration simultaneously in order to improve digital innovation capability
Parallel identification of O-GlcNAc-modified proteins from cell lysates
We report a new strategy for the parallel identification of O-GlcNAc-glycosylated proteins from cell lysates. The approach permits specific proteins of interest to be rapidly interrogated for the modification in any tissue or cell type and can be extended to peptides to facilitate the mapping of glycosylation sites. As an illustration of the approach, we identified four new O-GlcNAc-glycosylated proteins of low cellular abundance (c-Fos, c-Jun, ATF-1, and CBP) and two short regions of glycosylation in the enzyme O-GlcNAc transferase (OGT). The ability to target specific proteins across various tissue or cell types complements emerging proteomic technologies and should advance our understanding of this important posttranslational modification
Quantum Simulation of Antiferromagnetic Spin Chains in an Optical Lattice
Understanding exotic forms of magnetism in quantum mechanical systems is a
central goal of modern condensed matter physics, with implications from high
temperature superconductors to spintronic devices. Simulating magnetic
materials in the vicinity of a quantum phase transition is computationally
intractable on classical computers due to the extreme complexity arising from
quantum entanglement between the constituent magnetic spins. Here we employ a
degenerate Bose gas confined in an optical lattice to simulate a chain of
interacting quantum Ising spins as they undergo a phase transition. Strong spin
interactions are achieved through a site-occupation to pseudo-spin mapping. As
we vary an applied field, quantum fluctuations drive a phase transition from a
paramagnetic phase into an antiferromagnetic phase. In the paramagnetic phase
the interaction between the spins is overwhelmed by the applied field which
aligns the spins. In the antiferromagnetic phase the interaction dominates and
produces staggered magnetic ordering. Magnetic domain formation is observed
through both in-situ site-resolved imaging and noise correlation measurements.
By demonstrating a route to quantum magnetism in an optical lattice, this work
should facilitate further investigations of magnetic models using ultracold
atoms, improving our understanding of real magnetic materials.Comment: 12 pages, 9 figure
Atorvastatin reduces the ability of clopidogrel to inhibit platelet aggregation: A new drug-drug interaction
Background— We observed that the prodrug clopidogrel was less effective in inhibiting platelet aggregation with coadministration of atorvastatin during point-of-care platelet function testing. Because atorvastatin is metabolized by cytochrome P450 (CYP) 3A4, we hypothesized that clopidogrel might be activated by CYP3A4. Methods and Results— Platelet aggregation was measured in 44 patients undergoing coronary artery stent implantation treated with clopidogrel or clopidogrel plus pravastatin or atorvastatin, and in 27 volunteers treated with clopidogrel and either erythromycin or troleandomycin, CYP3A4 inhibitors, or rifampin, a CYP3A4 inducer. Atorvastatin, but not pravastatin, attenuated the antiplatelet activity of clopidogrel in a dose-dependent manner. Percent platelet aggregation was 34±23, 58±15 (P=0.027), 74±10 (P=0.002), and 89±7 (P=0.001) in the presence of clopidogrel and 0, 10, 20, and 40 mg of atorvastatin, respectively. Erythromycin attenuated platelet aggregation inhibition (55±12 versus 42±12% platelet aggregation; P=0.002), as did troleandomycin (78±18 versus 45±18% platelet aggregation; P less than 0.0003), whereas rifampin enhanced platelet aggregation inhibition (33±18 versus 56±20% platelet aggregation, P=0.001). Conclusions— CYP3A4 activates clopidogrel. Atorvastatin, another CYP3A4 substrate, competitively inhibits this activation. Use of a statin not metabolized by CYP3A4 and point-of-care platelet function testing may be warranted in patients treated with clopidogrel
Orbital excitation blockade and algorithmic cooling in quantum gases
Interaction blockade occurs when strong interactions in a confined few-body
system prevent a particle from occupying an otherwise accessible quantum state.
Blockade phenomena reveal the underlying granular nature of quantum systems and
allow the detection and manipulation of the constituent particles, whether they
are electrons, spins, atoms, or photons. The diverse applications range from
single-electron transistors based on electronic Coulomb blockade to quantum
logic gates in Rydberg atoms. We have observed a new kind of interaction
blockade in transferring ultracold atoms between orbitals in an optical
lattice. In this system, atoms on the same lattice site undergo coherent
collisions described by a contact interaction whose strength depends strongly
on the orbital wavefunctions of the atoms. We induce coherent orbital
excitations by modulating the lattice depth and observe a staircase-type
excitation behavior as we cross the interaction-split resonances by tuning the
modulation frequency. As an application of orbital excitation blockade (OEB),
we demonstrate a novel algorithmic route for cooling quantum gases. Our
realization of algorithmic cooling utilizes a sequence of reversible OEB-based
quantum operations that isolate the entropy in one part of the system, followed
by an irreversible step that removes the entropy from the gas. This work opens
the door to cooling quantum gases down to ultralow entropies, with implications
for developing a microscopic understanding of strongly correlated electron
systems that can be simulated in optical lattices. In addition, the close
analogy between OEB and dipole blockade in Rydberg atoms provides a roadmap for
the implementation of two-qubit gates in a quantum computing architecture with
natural scalability.Comment: 6 pages, 4 figure
Industry/University Collaboration at the University of Michigan-Dearborn: A Focus on Relevant Technology
https://deepblue.lib.umich.edu/bitstream/2027.42/154106/1/kampfner1998.pd
PPARα L162V underlies variation in serum triglycerides and subcutaneous fat volume in young males
<p>Abstract</p> <p>Background</p> <p>Of the five sub-phenotypes defining metabolic syndrome, all are known to have strong genetic components (typically 50–80% of population variation). Studies defining genetic predispositions have typically focused on older populations with metabolic syndrome and/or type 2 diabetes. We hypothesized that the study of younger populations would mitigate many confounding variables, and allow us to better define genetic predisposition loci for metabolic syndrome.</p> <p>Methods</p> <p>We studied 610 young adult volunteers (average age 24 yrs) for metabolic syndrome markers, and volumetric MRI of upper arm muscle, bone, and fat pre- and post-unilateral resistance training.</p> <p>Results</p> <p>We found the PPARα L162V polymorphism to be a strong determinant of serum triglyceride levels in young White males, where carriers of the V allele showed 78% increase in triglycerides relative to L homozygotes (LL = 116 ± 11 mg/dL, LV = 208 ± 30 mg/dL; p = 0.004). Men with the V allele showed lower HDL (LL = 42 ± 1 mg/dL, LV = 34 ± 2 mg/dL; p = 0.001), but women did not. Subcutaneous fat volume was higher in males carrying the V allele, however, exercise training increased fat volume of the untrained arm in V carriers, while LL genotypes significantly decreased in fat volume (LL = -1,707 ± 21 mm<sup>3</sup>, LV = 17,617 ± 58 mm<sup>3 </sup>; p = 0.002), indicating a systemic effect of the V allele on adiposity after unilateral training. Our study suggests that the primary effect of PPARα L162V is on serum triglycerides, with downstream effects on adiposity and response to training.</p> <p>Conclusion</p> <p>Our results on association of PPARα and triglycerides in males showed a much larger effect of the V allele than previously reported in older and less healthy populations. Specifically, we showed the V allele to increase triglycerides by 78% (p = 0.004), and this single polymorphism accounted for 3.8% of all variation in serum triglycerides in males (p = 0.0037).</p
A community-integrated home based depression intervention for older African Americans: descripton of the Beat the Blues randomized trial and intervention costs
ABSTRACT: BACKGROUND: Primary care is the principle setting for depression treatment; yet many older African Americans in the United States fail to report depressive symptoms or receive the recommended standard of care. Older African Americans are at high risk for depression due to elevated rates of chronic illness, disability and socioeconomic distress. There is an urgent need to develop and test new depression treatments that resonate with minority populations that are hard-to-reach and underserved and to evaluate their cost and cost-effectiveness. METHODS/DESIGN: Beat the Blues (BTB) is a single-blind parallel randomized trial to assess efficacy of a non-pharmacological intervention to reduce depressive symptoms and improve quality of life in 208 African Americans 55+ years old. It involves a collaboration with a senior center whose care management staff screen for depressive symptoms (telephone or in-person) using the Patient Health Questionnaire (PHQ-9). Individuals screened positive (PHQ-9 ≥ 5) on two separate occasions over 2 weeks are referred to local mental health resources and BTB. Interested and eligible participants who consent receive a baseline home interview and then are randomly assigned to receive BTB immediately or 4 months later (wait-list control). All participants are interviewed at 4 (main study endpoint) and 8 months at home by assessors masked to study assignment. Licensed senior center social workers trained in BTB meet with participants at home for up to 10 sessions over 4 months to assess care needs, make referrals/linkages, provide depression education, instruct in stress reduction techniques, and use behavioral activation to identify goals and steps to achieve them. Key outcomes include reduced depressive symptoms (primary), reduced anxiety and functional disability, improved quality of life, and enhanced depression knowledge and behavioral activation (secondary). Fidelity is enhanced through procedure manuals and staff training and monitored by face-to-face supervision and review of taped sessions. Cost and cost effectiveness is being evaluated. DISCUSSION: BTB is designed to bridge gaps in mental health service access and treatments for older African Americans. Treatment components are tailored to specific care needs, depression knowledge, preference for stress reduction techniques, and personal activity goals. Total costs are 146.16 per participant/per month. TRIAL REGISTRATION: ClinicalTrials.gov #NCT00511680
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