438 research outputs found
Electromagnetic Property Sensing: A New Paradigm of Integrated Sensing and Communication
Integrated sensing and communication (ISAC) has opened up numerous
game-changing opportunities for future wireless systems. In this paper, we
develop a novel scheme that utilizes orthogonal frequency division multiplexing
(OFDM) pilot signals in ISAC systems to sense the electromagnetic (EM) property
of the target and thus also identify the material of the target. Specifically,
we first establish an end-to-end EM propagation model by means of Maxwell
equations, where the EM property of the target is captured by a closed-form
expression of the ISAC channel, incorporating the Lippmann-Schwinger equation
and the method of moments (MOM) for discretization. We then model the relative
permittivity and conductivity distribution (RPCD) within a specified detection
region. Based on the sensing model, we introduce a multi-frequency-based EM
property sensing method by which the RPCD can be reconstructed from compressive
sensing techniques that exploits the joint sparsity structure of the EM
property vector. To improve the sensing accuracy, we design a beamforming
strategy from the communications transmitter based on the Born approximation
that can minimize the mutual coherence of the sensing matrix. The optimization
problem is cast in terms of the Gram matrix and is solved iteratively to obtain
the optimal beamforming matrix. Simulation results demonstrate the efficacy of
the proposed method in achieving high-quality RPCD reconstruction and accurate
material classification. Furthermore, improvements in RPCD reconstruction
quality and material classification accuracy are observed with increased
signal-to-noise ratio (SNR) or reduced target-transmitter distance
Exploring virus relationships based on virus-host protein-protein interaction network
<p>Abstract</p> <p>Background</p> <p>Currently, several systems have been proposed to classify viruses and indicate the relationships between different ones, though each system has its limitations because of the complexity of viral origins and their rapid evolution rate. We hereby propose a new method to explore the relationships between different viruses.</p> <p>Method</p> <p>A new method, which is based on the virus-host protein-protein interaction network, is proposed in this paper to categorize viruses. The distances between 114 human viruses, including 48 HIV-1 and HIV-2 viruses, are estimated according to the protein-protein interaction network between these viruses and humans.</p> <p>Conclusions/significance</p> <p>The results demonstrated that our method can disclose not only relationships consistent with the taxonomic results of currently used systems of classification but also the potential relationships that the current virus classification systems have not revealed. Moreover, the method points to a new direction where the functional relationships between viruses and hosts can be used to explore the virus relationships on a systematic level.</p
Family association study between INSR gene polymorphisms and PCOS in Han Chinese
<p>Abstract</p> <p>Background</p> <p>Polycystic ovary syndrome (PCOS) is a complex disease having both genetic and environmental components. Candidate genes with insulin metabolism have been hypothesized to be involved in the etiology of this syndrome. In the present study, we investigated the genetic association between polymorphisms in the insulin receptor (INSR) gene and PCOS.</p> <p>Methods</p> <p>A total of 260 family trios were recruited and performed a family-based analysis to assess linkage and association between four single nucleotide polymorphisms (SNPs) (rs1799817, rs2059807, rs8108622 and rs10500204) of INSR gene and PCOS.</p> <p>Results</p> <p>Using the transmission disequilibrium test (TDT), we failed to find that rs1799817 (p = 0.486), rs2059807 (p = 0.195), rs8108622 (p = 0.866) and rs10500204 (p = 1.0) were significantly overtransmitted to PCOS offspring from their parents.</p> <p>Conclusion</p> <p>No significant evidence of association or linkage was found in the four tested markers, indicating that our family samples did not support susceptibility of the INSR gene to PCOS.</p
S3E: A Large-scale Multimodal Dataset for Collaborative SLAM
With the advanced request to employ a team of robots to perform a task
collaboratively, the research community has become increasingly interested in
collaborative simultaneous localization and mapping. Unfortunately, existing
datasets are limited in the scale and variation of the collaborative
trajectories, even though generalization between inter-trajectories among
different agents is crucial to the overall viability of collaborative tasks. To
help align the research community's contributions with realistic multiagent
ordinated SLAM problems, we propose S3E, a large-scale multimodal dataset
captured by a fleet of unmanned ground vehicles along four designed
collaborative trajectory paradigms. S3E consists of 7 outdoor and 5 indoor
sequences that each exceed 200 seconds, consisting of well temporal
synchronized and spatial calibrated high-frequency IMU, high-quality stereo
camera, and 360 degree LiDAR data. Crucially, our effort exceeds previous
attempts regarding dataset size, scene variability, and complexity. It has 4x
as much average recording time as the pioneering EuRoC dataset. We also provide
careful dataset analysis as well as baselines for collaborative SLAM and single
counterparts. Data and more up-to-date details are found at
https://github.com/PengYu-Team/S3E
CRAI Biblioteca del Campus de Mundet. Memòria d'activitats 2016
Memòria que recull les activitats realitzades al CRAI Biblioteca del Campus de Mundet durant l'any 2016
P21cip-Overexpression in the Mouse β Cells Leads to the Improved Recovery from Streptozotocin-Induced Diabetes
Under normal conditions, the regeneration of mouse β cells is mainly dependent on their own duplication. Although there is evidence that pancreatic progenitor cells exist around duct, whether non-β cells in the islet could also potentially contribute to β cell regeneration in vivo is still controversial. Here, we developed a novel transgenic mouse model to study the pancreatic β cell regeneration, which could specifically inhibit β cell proliferation by overexpressing p21cip in β cells via regulation of the Tet-on system. We discovered that p21 overexpression could inhibit β-cell duplication in the transgenic mice and these mice would gradually suffer from hyperglycemia. Importantly, the recovery efficiency of the p21-overexpressing mice from streptozotocin-induced diabetes was significantly higher than control mice, which is embodied by better physiological quality and earlier emergence of insulin expressing cells. Furthermore, in the islets of these streptozotocin-treated transgenic mice, we found a large population of proliferating cells which expressed pancreatic duodenal homeobox 1 (PDX1) but not markers of terminally differentiated cells. Transcription factors characteristic of early pancreatic development, such as Nkx2.2 and NeuroD1, and pancreatic progenitor markers, such as Ngn3 and c-Met, could also be detected in these islets. Thus, our work showed for the first time that when β cell self-duplication is repressed by p21 overexpression, the markers for embryonic pancreatic progenitor cells could be detected in islets, which might contribute to the recovery of these transgenic mice from streptozotocin-induced diabetes. These discoveries could be important for exploring new diabetes therapies that directly promote the regeneration of pancreatic progenitors to differentiate into islet β cells in vivo
Prevalence of inappropriateness of elemene injection for hospitalized cancer patients: a multicenter retrospective study
Background: Elemene injection could provide clinical benefit for the treatment of various cancers, but the clinical evidence is weak. Thus, its wide use in China has raised concerns about the appropriateness of its use.Methods: This was a multicenter retrospective study to evaluate the prevalence of inappropriateness of elemene injection for hospitalized cancer patients. Patients who met the inclusion criteria were retrospectively included, and demographic characteristics were extracted from the hospital information systems. The inappropriateness of elemene injection use was assessed using the preset criteria, and the prevalence was calculated. Multivariate logistic analysis was applied to identify any factors associated with inappropriate use.Results: A total of 275 patients were included in the analysis. The median age was 62Â years, and 30.9% were females. The most common cancer was lung cancer (24.0%), and 68.2% of the patients were receiving chemotherapy. The overall prevalence of inappropriateness was 61.8%. The most common reason for inappropriateness was inappropriate indications, and the second was inappropriate doses. Age and oncological department were significant risk factors associated with inappropriate use, while lung cancer, liver cancer and admission to cardiothoracic surgery were associated with a low risk of inappropriate use.Conclusion: The prevalence of inappropriateness among hospitalized elemene injection users was high. More efforts, especially those to improve the appropriateness of indications, should be made to improve the rational use of elemene, as well as other complementary medicines. Physicians should take caution to avoid inappropriate use when prescribing drugs with limited clinical evidence
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