227 research outputs found
Robust Beamforming and Rate-Splitting Design for Next Generation Ultra-Reliable and Low-Latency Communications
The next generation ultra-reliable and low-latency communications (xURLLC)
need novel design to provide satisfactory services to the emerging
mission-critical applications. To improve the spectrum efficiency and enhance
the robustness of xURLLC, this paper proposes a robust beamforming and
rate-splitting design in the finite blocklength (FBL) regime for downlink
multi-user multi-antenna xURLLC systems. In the design, adaptive rate-splitting
is introduced to flexibly handle the complex inter-user interference and thus
improve the spectrum efficiency. Taking the imperfection of the channel state
information at the transmitter (CSIT) into consideration, a max-min user rate
problem is formulated to optimize the common and private beamforming vectors
and the rate-splitting vector under the premise of ensuring the requirements of
transmission latency and reliability of all the users. The optimization problem
is intractable due to the non-convexity of the constraint set and the infinite
constraints caused by CSIT uncertainties. To solve it, we convert the infinite
constraints into finite ones by the S-Procedure method and transform the
original problem into a difference of convex (DC) programming. A constrained
concave convex procedure (CCCP) and the Gaussian randomization based iterative
algorithm is proposed to obtain a local minimum. Simulation results confirm the
convergence, robustness and effectiveness of the proposed robust beamforming
and rate-splitting design in the FBL regime. It is also shown that the proposed
robust design achieves considerable performance gain in the worst user rate
compared with existing transmission schemes under various blocklength and block
error rate requirements.Comment: 12 pages, 9 figure
Clinical efficacy of apatinib as a second-line treatment for advanced pancreatic cancer in a Chinese tertiary cancer health facility
Purpose: To study the effectiveness and safety of apatinib as second-line treatment for advanced pancreatic cancer (APC) in a Chinese tertiary cancer hospital.
Methods: Two groups of APC patients who received treatment with single-agent or two-drug combination of gemcitabine-based first-line therapy (50 per group) in The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing were assessed. The study group received apatinib at or above the second line treatment, while the control group was treated with second-line chemotherapy, which was different from first-line single-drug chemotherapy. Patients received treatments until there was improvement in their conditions, or until adverse reactions became intolerable. Complete remission (CR), partial remission (PR), disease stabilization (SD), disease progression (PD), incidence of adverse reactions, and progression-free survival (PFS) of the patients were recorded.
Results: The number of PR cases in APC patients who received apatinib as second-line therapy, and the number of PD patients were higher than the corresponding populations in the control group (p < 0.05). Treatment effectiveness was significantly higher in study group patients than in control subjects (p < 0.05). However, the incidence of adverse reactions was lower in the study group than in control group. Median PFS in the study group (5 months) was significantly higher than that of the control group (4.1 months, p < 0.05).
Conclusion: The clinical efficacy of apatinib as second-line treatment for advanced pancreatic cancer is higher than that of the single drug. Apatinib is associated with low incidence of adverse reactions which prolongs PFS. Thus, apatinib has potentials for the clinical management of pancreatic cancer
Cooperative Beamforming Design for Multiple RIS-Assisted Communication Systems
Reconfigurable intelligent surface (RIS) provides a promising way to build
programmable wireless transmission environments. Owing to the massive number of
controllable reflecting elements on the surface, RIS is capable of providing
considerable passive beamforming gains. At present, most related works mainly
consider the modeling, design, performance analysis and optimization of
single-RIS-assisted systems. Although there are a few of works that investigate
multiple RISs individually serving their associated users, the cooperation
among multiple RISs is not well considered as yet. To fill the gap, this paper
studies a cooperative beamforming design for multi-RIS-assisted communication
systems, where multiple RISs are deployed to assist the downlink communications
from a base station to its users. To do so, we first model the general channel
from the base station to the users for arbitrary number of reflection links.
Then, we formulate an optimization problem to maximize the sum rate of all
users. Analysis shows that the formulated problem is difficult to solve due to
its non-convexity and the interactions among the decision variables. To solve
it effectively, we first decouple the problem into three disjoint subproblems.
Then, by introducing appropriate auxiliary variables, we derive the closed-form
expressions for the decision variables and propose a low-complexity cooperative
beamforming algorithm. Simulation results have verified the effectiveness of
the proposed algorithm through comparison with various baseline methods.
Furthermore, these results also unveil that, for the sum rate maximization,
distributing the reflecting elements among multiple RISs is superior to
deploying them at one single RIS
Speckle reducing bilateral filter for cattle follicle segmentation
<p>Abstract</p> <p>Background</p> <p>Ultrasound imaging technology has wide applications in cattle reproduction and has been used to monitor individual follicles and determine the patterns of follicular development. However, the speckles in ultrasound images affect the post-processing, such as follicle segmentation and finally affect the measurement of the follicles. In order to reduce the effect of speckles, a bilateral filter is developed in this paper.</p> <p>Results</p> <p>We develop a new bilateral filter for speckle reduction in ultrasound images for follicle segmentation and measurement. Different from the previous bilateral filters, the proposed bilateral filter uses normalized difference in the computation of the Gaussian intensity difference. We also present the results of follicle segmentation after speckle reduction. Experimental results on both synthetic images and real ultrasound images demonstrate the effectiveness of the proposed filter.</p> <p>Conclusions</p> <p>Compared with the previous bilateral filters, the proposed bilateral filter can reduce speckles in both high-intensity regions and low intensity regions in ultrasound images. The segmentation of the follicles in the speckle reduced images by the proposed method has higher performance than the segmentation in the original ultrasound image, and the images filtered by Gaussian filter, the conventional bilateral filter respectively.</p
The rice ERF transcription factor OsERF922 negatively regulates resistance to Magnaporthe oryzae and salt tolerance
Rice OsERF922, encoding an APETELA2/ethylene response factor (AP2/ERF) type transcription factor, is rapidly and strongly induced by abscisic acid (ABA) and salt treatments, as well as by both virulent and avirulent pathovars of Magnaporthe oryzae, the causal agent of rice blast disease. OsERF922 is localized to the nucleus, binds specifically to the GCC box sequence, and acts as a transcriptional activator in plant cells. Knockdown of OsERF922 by means of RNAi enhanced resistance against M. oryzae. The elevated disease resistance of the RNAi plants was associated with increased expression of PR, PAL, and the other genes encoding phytoalexin biosynthetic enzymes and without M. oryzae infection. In contrast, OsERF922-overexpressing plants showed reduced expression of these defence-related genes and enhanced susceptibility to M. oryzae. In addition, the OsERF922-overexpressing lines exhibited decreased tolerance to salt stress with an increased Na+/K+ ratio in the shoots. The ABA levels were found increased in the overexpressing lines and decreased in the RNAi plants. Expression of the ABA biosynthesis-related genes, 9-cis-epoxycarotenoid dioxygenase (NCED) 3 and 4, was upregulated in the OsERF922-overexpressing plants, and NCED4 was downregulated in the RNAi lines. These results suggest that OsERF922 is integrated into the cross-talk between biotic and abiotic stress-signalling networks perhaps through modulation of the ABA levels
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Comparison of T Helper Cell Patterns in Primary Open-Angle Glaucoma and Normal-Pressure Glaucoma
Background: HSP60-related immunological activities are found in normal-pressure glaucoma (NPG) patients, in whom an elevated intraocular pressure (IOP) found in primary open-angle glaucoma (POAG) is not observed. HSP60 was found in POAG and NPG patients, while anti-HSP60 level was mainly found to be higher in NPG patients. The purpose of this study was to compare the percentages of Th cells and levels of related cytokines, attempting to provide evidence to explain this discrepancy. Material/Methods Blood samples from POAG, NPG, and normal control (NC) groups were collected and peripheral blood monocytes were isolated and cultured with or without the stimulation of HSP60. Flow cytometry and enzyme-linked immunosorbent assay were used to assess the percentages of Th1, Th2, Th17, and Treg cells, as well as HSP60 antibody levels and related cytokine levels, before and after culture. Results: Significantly higher titers of anti-HSP60 were observed only in NPG patients. Comparable Th1 and Th2 cell frequencies, IL-4 level, and IFN-γ level were found in POAG and NPG patients, while higher Treg cell frequency was only found in POAG patients. After culturing with HSP60, increased Th2 frequencies and decreased Th1 frequencies were observed in the POAG, NPG, and NC groups, while increased Treg frequency was only identified in the POAG and NC groups. Conclusions: Different Th cell patterns were observed among POAG, NPG, and NC groups. Lack of induction of Treg cells and imbalance of the pro-inflammatory and anti-inflammatory response patterns of Th cells exist in some NPG patients
Lifor Solution: An Alternative Preservation Solution in Small Bowel Transplantation
Background and Objectives. The intestinal mucosa is extremely sensitive to ischemia. Better intestinal preservation is the first step to improve the results of intestinal transplantation. The aim of the study is to investigate the effect of cold Lifor solution on preservation of swine small bowel. Methods. Swine ileum segments (200 cm) were allotransplanted heterotopically after 9-hour cold storage with UW solution (group 1, n=6), with Lifor solution (group 2, n=6), or without storage (group 3, n=6), respectively. After cold storage, mucosal adenosine triphosphate (ATP) concentrations and histopathologic analysis after preservation were performed. At day 7 after the transplantation, intestinal absorptive function was also observed. Results. After 9 h cold preservation, pathological changes, the content of ATP in the intestinal mucosa, and the intestinal absorptive function after transplantation in group 2 were similar to those of group 1. Conclusion. The effect of cold storage of swine small bowel with Lifor solution is similar to that of UW solution. It may provide additional rationale for further exploration of Lifor as an alternative preservation solution in small bowel transplantation
OWL: A Large Language Model for IT Operations
With the rapid development of IT operations, it has become increasingly
crucial to efficiently manage and analyze large volumes of data for practical
applications. The techniques of Natural Language Processing (NLP) have shown
remarkable capabilities for various tasks, including named entity recognition,
machine translation and dialogue systems. Recently, Large Language Models
(LLMs) have achieved significant improvements across various NLP downstream
tasks. However, there is a lack of specialized LLMs for IT operations. In this
paper, we introduce the OWL, a large language model trained on our collected
OWL-Instruct dataset with a wide range of IT-related information, where the
mixture-of-adapter strategy is proposed to improve the parameter-efficient
tuning across different domains or tasks. Furthermore, we evaluate the
performance of our OWL on the OWL-Bench established by us and open IT-related
benchmarks. OWL demonstrates superior performance results on IT tasks, which
outperforms existing models by significant margins. Moreover, we hope that the
findings of our work will provide more insights to revolutionize the techniques
of IT operations with specialized LLMs.Comment: 31 page
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