800 research outputs found
A Joint Model and Data Driven Method for Distributed Estimation
This paper considers the problem of distributed estimation in wireless sensor
networks (WSN), which is anticipated to support a wide range of applications
such as the environmental monitoring, weather forecasting, and location
estimation. To this end, we propose a joint model and data driven distributed
estimation method by designing the optimal quantizers and fusion center (FC)
based on the Bayesian and minimum mean square error (MMSE) criterions. First,
universal mean square error (MSE) lower bound for the quantization-based
distributed estimation is derived and adopted as the design metric for the
quantizers. Then, the optimality of the mean-fusion operation for the FC with
MMSE criterion is proved. Next, by exploiting different levels of the statistic
information of the desired parameter and observation noise, a joint model and
data driven method is proposed to train parts of the quantizer and FC modules
as deep neural networks (DNNs), and two loss functions derived from the MMSE
criterion are adopted for the sequential training scheme. Furthermore, we
extend the above results to the case with multi-bit quantizers, considering
both the parallel and one-hot quantization schemes. Finally, simulation results
reveal that the proposed method outperforms the state-of-the-art schemes in
typical scenarios.Comment: in IEEE Internet of Things Journa
Assessing The Helpfulness Of Online Product Review: A Progressive Experimental Approach
The online product review has been advocated as an important determinant of a consumer’s purchase decision. Although prior research has been instrumental in articulating the benefits of the online product review, there remains a dearth of investigation on what kind of product review will be perceived to be helpful to a consumer. Through two sequential experiments, we investigate the endogenous features of a product review that influence the helpfulness of the perceived product review. Product review helpfulness is manifested by the review’s source credibility and the review’s diagnosticity. Results from the first experiment reveal that a consumer review is more credible than the expert review. Leading from this, we conduct the second experiment and focus on examining the influence of the type of consumer review (reflected the level of review abstractness). The results indicate that subjects perceive the concrete consumer review (i.e., of low abstractness) as more diagnostic than the abstract consumer review. Examining the two experimental results holistically, we deduce that consumer reviews with low levels of abstractness (i.e., are highly concrete) could yield higher degrees of perceived helpfulness compared with highly abstract consumer reviews and expert reviews. The theoretical and practical implications are discussed
KINETIC AND KINEMATIC DIFFERENCES OF TWO VOLLEYBALL-SPIKING JUMPS
The purpose of this study was to investigate the net muscle moments and work on the lower limbs in two different volleyball-spiking jumps by inverse dynamics. A Kistler force
platform (600 Hz) was synchronized with a Peak high speed camera (120Hz) to collect the volleyball jumping action. Sixteen volleyball players (8 males and 8 females) were the
subjects of the study. The results revealed that the work done in knee joints during eccentric contraction were greater than ankle and hip joints in both two volleyball jumps. In addition, the hip has a greater work contribution on both hop and step-close jump
Circulating tissue factor-positive procoagulant microparticles in patients with type 1 diabetes
Aim: To investigate the count of circulating tissue factor-positive (TF+) procoagulant microparticles (MPs) in patients with type 1 diabetes mellitus (T1DM). Methods: This case-control study included patients with T1DM and age and sex-matched healthy volunteers. The counts of phosphatidylserine-positive (PS+) MPs and TF(+)PS(+)MPs and the subgroups derived from different cell types were measured in the peripheral blood sample of the two groups using multicolor flow cytometric assay. We compared the counts of each MP between groups as well as the ratio of the TF(+)PS(+)MPs and PS(+)MPs (TF(+)PS(+)MPs/PS(+)MPs). Results: We recruited 36 patients with T1DM and 36 matched healthy controls. Compared with healthy volunteers, PS(+)MPs, TF(+)PS(+)MPs and TF(+)PS(+)MPs/PS(+)MPs were elevated in patients with T1DM (PS(+)MPs: 1078.5 +/- 158.08 vs 686.84 +/- 122.04/mu L, P <0.001; TF(+)PS(+)MPs: 202.10 +/- 47.47 vs 108.33 +/- 29.42/mu L, P <0.001; and TF(+)PS(+)MPs/PS(+)MPs: 0.16 +/- 0.04 vs 0.19 +/- 0.05, P = 0.004), mostly derived from platelet, lymphocytes and endothelial cells. In the subgroup analysis, the counts of total and platelet TF(+)PS(+)MPs were increased in patients with diabetic retinopathy (DR) and with higher HbA1c, respectively. Conclusion: Circulating TF(+)PS(+)MPs and those derived from platelet, lymphocytes and endothelial cells were elevated in patients with T1DM.De tre första författarna delar förstaförfattarskapet.</p
Discordant associations of lipid parameters with albuminuria and chronic kidney disease: a population-based study
Antioxidant Activities of the Methanol Extracts of Various Parts of Phalaenopsis Orchids with White, Yellow, and Purple Flowers
Phalaenopsis (Phal.) orchids including white, yellow, and purple flowers are some of the most important commercial orchids worldwide. These flowering plants can be considered to be promising sources of antioxidants since several medicinal orchids were shown to have potential antioxidant activities. The antioxidant activities and several secondary metabolite compounds of the methanolic extracts of four parts (the root, pedicel, leaf, and flower) of three hybrids of white (Phal. ‘City More’), yellow (Phal. ‘Sogo Meili’), and purple (Phal. ‘Queen Beer’) flowering orchids were investigated. Results showed that the highest levels of chlorophyll a and chlorophyll b were respectively obtained in leaf extracts of white and purple orchids, whereas carotenoid showed the highest content in the flower extract of the yellow orchid. Among all tested extracts, flavonoids and anthocyanin demonstrated the highest levels in the flower extract of the purple orchid, whereas the highest level of polyphenols was observed in the flower extract of the yellow orchid. The leaf extract of the white orchid was the most effective extract with a 50% inhibitory concentration in the DPPH-scavenging activity assay, while the highest ferrous iron-chelating effect was observed in flower extracts of the yellow orchid and purple orchid, and the pedicel extract of the purple orchid. In the reducing power assay, the flower extract of the white orchid showed the most potent extract, followed by the leaf extract of the yellow orchid and the flower extract of the purple orchid. Relationships between flower colors and antioxidant activities of these orchids showed them to be potential sources of antioxidants for both medicinal use and stress-tolerance in these orchids
Effects of Herb-Partitioned Moxibustion on the miRNA Expression Profiles in Colon from Rats with DSS-Induced Ulcerative Colitis
Objective. This study explored the mechanism of herb-partitioned moxibustion (HM) on dextran sulfate sodium- (DSS-) induced ulcerative colitis (UC) from the miRNA perspective. Methods. Rats were randomly divided into 3 groups [normal control (NC) group, UC model (UC) group, and herb-partitioned moxibustion (UCHM) group]. The UC and UCHM groups were administered 4% DSS for 7 days. The UCHM group received HM at the Tianshu (bilateral, ST25). The effect of HM on UC was observed and the miRNA expression profile in the colon tissues was analyzed. Results. Compared with the UC group, the body weights were significantly higher in the UCHM group on day 14 (P<0.001); the macroscopic colon injury scores and microscopic histopathology scores in the UCHM group decreased (P<0.05); and there were 15 differentially expressed miRNAs in the UCHM group. The changes in miR-184 and miR-490-5p expression levels on the UC were reversed by HM intervention. Validation using qRT-PCR showed that two miRNAs expression trend was consistent with the sequencing results. Conclusion. HM at ST25 might regulate miR-184 and miR-490-5p expression, act on the transcription of their target genes to regulate inflammatory signaling pathways, and attenuate inflammation and tissue injury in the colons of rats with DSS-induced UC
- …