6,844 research outputs found
Dynamic human resource selection for business process exceptions
A key capability of today's organizations is to flexibly and effectively react to unexpected events. A critical case of an unexpected event is sudden unavailability of human resources, which was not properly addressed by existing resource allocation approaches. This paper proposes a systematic approach that analyzes event logs to select suitable substitutes if the initial human resources become unavailable. The approach uses process mining and social network analysis to derive a metric called degree of substitution, which measures how much the work experiences of the human resources overlap, from the two perspectives: task execution and transfer of work. Along with the metric, suitable substitutes are also identified. A simulation demonstrates that the approach identifies suitable substitutes more effectively and accurately than existing allocation methods such as roleābased allocation or random allocation. The proposed approach will increase the effectiveness of dynamic allocation of human resources, especially in an exceptional situation.11Yscopu
Dominant Channel Estimation via MIPS for Large-Scale Antenna Systems with One-Bit ADCs
In large-scale antenna systems, using one-bit analog-to-digital converters
(ADCs) has recently become important since they offer significant reductions in
both power and cost. However, in contrast to high-resolution ADCs, the coarse
quantization of one-bit ADCs results in an irreversible loss of information. In
the context of channel estimation, studies have been developed extensively to
combat the performance loss incurred by one-bit ADCs. Furthermore, in the field
of array signal processing, direction-of-arrival (DOA) estimation combined with
one-bit ADCs has gained growing interests recently to minimize the estimation
error. In this paper, a channel estimator is proposed for one-bit ADCs where
the channels are characterized by their angular geometries, e.g., uniform
linear arrays (ULAs). The goal is to estimate the dominant channel among
multiple paths. The proposed channel estimator first finds the DOA estimate
using the maximum inner product search (MIPS). Then, the channel fading
coefficient is estimated using the concavity of the log-likelihood function.
The limit inherent in one-bit ADCs is also investigated, which results from the
loss of magnitude information.Comment: to appear in GLOBECOM 2018, Abu Dhabi, UA
Human Brain Astrocytes Mediate TRAIL-mediated Apoptosis after Treatment with IFN-Ī³
TNF-related apoptosis inducing ligand (TRAIL) expressions were studied in primary human brain astrocytes in response to pro-inflammatory cytokines. When astrocytes were treated with IL-1Ī², TNF-Ī± or IFN-Ī³, TRAIL was induced in cultured fetal astrocytes. In particular, IFN-Ī³ induced the highest levels of TRAIL in cultured astrocytes. When astrocytes were prereated with IFN-Ī³, they induced apoptosis in TRAIL-sensitive Peer cells. Our results suggest that IFN-Ī³ modulates the expression of TRAIL in astrocytes, which may enhance cytotoxic sensitivity of infiltrating immune cells or brain cells other than astrocytes during inflammation of brain
Superconducting transition of a two-dimensional Josephson junction array in weak magnetic fields
The superconducting transition of a two-dimensional (2D) Josephson junction
array exposed to weak magnetic fields has been studied experimentally.
Resistance measurements reveal a superconducting-resistive phase boundary in
serious disagreement with the theoretical and numerical expectations. Critical
scaling analyses of the characteristics indicate contrary to the
expectations that the superconducting-to-resistive transition in weak magnetic
fields is associated with a melting transition of magnetic-field-induced
vortices directly from a pinned-solid phase to a liquid phase. The expected
depinning transition of vortices from a pinned-solid phase to an intermediate
floating-solid phase was not observed. We discuss effects of the
disorder-induced random pinning potential on phase transitions of vortices in a
2D Josephson junction array.Comment: 9 pages, 7 figures (EPS+JPG format), RevTeX
Acupuncture for the treatment of tinnitus: a systematic review of randomized clinical trials
BACKGROUND: Complementary and alternative medicine (CAM) has frequently been used to treat tinnitus, and acupuncture is a particularly popular option. The objective of this review was to assess the evidence concerning the effectiveness of acupuncture as a treatment for tinnitus. METHODS: Fourteen databases were searched from the dates of their creation to July 4th, 2012. Randomized clinical trials (RCTs) were included if acupuncture was used as the sole treatment. The Cochrane risk of bias tool was used to assess the risk of bias. RESULTS: A total of 9 RCTs met all the inclusion criteria. Their methodological quality was mostly poor. Five RCTs compared the effectiveness of acupuncture or electroacupuncture with sham acupuncture for treating tinnitus. The results failed to show statistically significant improvements. Two RCTs compared a short one-time scalp acupuncture treatment with the use of penetrating sham acupuncture at non-acupoints in achieving subjective symptom relief on a visual analog scale; these RCTs demonstrated significant positive effects with scalp acupuncture. Two RCTs compared acupuncture with conventional drug treatments. One of these RCTs demonstrated that acupuncture had statistically significant effects on the response rate in patients with nervous tinnitus, but the other RCT did not demonstrate significant effects in patients with senile tinnitus. CONCLUSIONS: The number, size and quality of the RCTs on the effectiveness of acupuncture for the treatment of tinnitus are not sufficient for drawing definitive conclusions. Further rigorous RCTs that overcome the many limitations of the current evidence are warranted
Quantitative in vivo measurement of early axonal transport deficits in a triple transgenic mouse model of Alzheimerās disease using manganese-enhanced MRI
Impaired axonal transport has been linked to the pathogenic processes of Alzheimerās disease (AD) in which axonal swelling and degeneration are prevalent. The development of non-invasive neuroimaging methods to quantitatively assess in vivo axonal transport deficits would be enormously valuable to visualize early, yet subtle, changes in the AD brain, to monitor the disease progression and to quantify the effect of drug intervention. A triple transgenic mouse model of AD closely resembles human AD neuropathology. In this study, we investigated age-dependent alterations in the axonal transport rate in a longitudinal assessment of the triple transgenic mouse olfactory system, using fast multi-sliced T1 mapping with manganese-enhanced MRI. The data show that impairment in axonal transport is a very early event in AD pathology in these mice, preceding both deposition of AĪ² plaques and formation of Tau fibrils
Acinetobacter baumannii invades epithelial cells and outer membrane protein A mediates interactions with epithelial cells
<p>Abstract</p> <p>Background</p> <p><it>Acinetobacter baumannii </it>is a nosocomial pathogen of increasing importance, but the pathogenic mechanism of this microorganism has not been fully explored. This study investigated the potential of <it>A. baumannii </it>to invade epithelial cells and determined the role of <it>A. baumannii </it>outer membrane protein A (AbOmpA) in interactions with epithelial cells.</p> <p>Results</p> <p><it>A. baumannii </it>invaded epithelial cells by a zipper-like mechanism, which is associated with microfilament- and microtubule-dependent uptake mechanisms. Internalized bacteria were located in the membrane-bound vacuoles. Pretreatment of recombinant AbOmpA significantly inhibited the adherence to and invasion of <it>A. baumannii </it>in epithelial cells. Cell invasion of isogenic AbOmpA<sup>- </sup>mutant significantly decreased as compared with wild-type bacteria. In a murine pneumonia model, wild-type bacteria exhibited a severe lung pathology and induced a high bacterial burden in blood, whereas AbOmpA<sup>- </sup>mutant was rarely detected in blood.</p> <p>Conclusion</p> <p><it>A. baumannii </it>adheres to and invades epithelial cells. AbOmpA plays a major role in the interactions with epithelial cells. These findings contribute to the understanding of <it>A. baumannii </it>pathogenesis in the early stage of bacterial infection.</p
- ā¦