• Title/Summary/Keyword: Suboptimal

Search Result 459, Processing Time 0.029 seconds

Low-complexity Sampling Set Selection for Bandlimited Graph Signals (대역폭 제한 그래프신호를 위한 저 복잡도 샘플링 집합 선택 알고리즘)

  • Kim, Yoon Hak
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.24 no.12
    • /
    • pp.1682-1687
    • /
    • 2020
  • We study the problem of sampling a subset of nodes of graphs for bandlimited graph signals such that the signal values on the sampled nodes provide the most information in order to reconstruct the original graph signal. Instead of directly minimizing the reconstruction error, we focus on minimizing the upper bound of the reconstruction error to reduce the complexity of the selection process. We further simplify the upper bound by applying useful approximations to propose a low-weight greedy selection process that is iteratively conducted to find a suboptimal sampling set. Through the extensive experiments for various graphs, we inspect the performance of the proposed algorithm by comparing with different sampling set selection methods and show that the proposed technique runs fast while preserving a competitive reconstruction performance, yielding a practical solution to real-time applications.

In vitro maturation on a soft agarose matrix enhances the developmental ability of pig oocytes derived from small antral follicles

  • Park, Ji Eun;Lee, Seung Tae;Lee, Geun-Shik;Lee, Eunsong
    • Journal of Animal Reproduction and Biotechnology
    • /
    • v.37 no.1
    • /
    • pp.34-41
    • /
    • 2022
  • In vivo oocytes grow and mature in ovarian follicles whereas oocytes are matured in vitro in plastic culture dishes with a hard surface. In vivo oocytes show a superior developmental ability to in vitro counterparts, indicating suboptimal environments of in vitro culture. This study aimed to evaluate the influence of an agarose matrix as a culture substrate during in vitro maturation (IVM) on the development of pig oocytes derived from small antral follicles (SAFs). Cumulus-oocyte complexes (COCs) retrieved from SAFs were grown in a plastic culture dish without an agarose matrix and then cultured for maturation in a plastic dish coated without (control) or with a 1% or 2% (w/v) agarose hydrogel. Then, the effect of the soft agarose matrix on oocyte maturation and embryonic development was assessed by analyzing intra-oocyte contents of glutathione (GSH) and reactive oxygen species (ROS), expression of VEGFA, HIF1A, and PFKP genes, and blastocyst formation after parthenogenesis. IVM of pig COCs on a 1% (w/v) agarose matrix showed a significantly higher blastocyst formation, intra-oocyte GSH contents, and transcript abundance of VEGFA. Moreover, a significantly lower intra-oocyte ROS content was detected in oocytes matured on the 1% and 2% (w/v) agarose matrices than in control. Our results demonstrated that IVM of SAFs-derived pig oocytes on a soft agarose matrix enhanced developmental ability by improving the cytoplasmic maturation of oocytes through redox balancing and regulation of gene expression.

Spatial Correlation-based Resource Sharing in Cognitive Radio SWIPT Networks

  • Rong, Mei;Liang, Zhonghua
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.16 no.9
    • /
    • pp.3172-3193
    • /
    • 2022
  • Cognitive radio-simultaneous wireless information and power transfer (CR-SWIPT) has attracted much interest since it can improve both the spectrum and energy efficiency of wireless networks. This paper focuses on the resource sharing between a point-to-point primary system (PRS) and a multiuser multi-antenna cellular cognitive radio system (CRS) containing a large number of cognitive users (CUs). The resource sharing optimization problem is formulated by jointly scheduling CUs and adjusting the transmit power at the cognitive base station (CBS). The effect of accessing CUs' spatial channel correlation on the possible transmit power of the CBS is investigated. Accordingly, we provide a low-complexity suboptimal approach termed the semi-correlated semi-orthogonal user selection (SC-SOUS) algorithm to enhance the spectrum efficiency. In the proposed algorithm, CUs that are highly correlated to the information decoding primary receiver (IPR) and mutually near orthogonal are selected for simultaneous transmission to reduce the interference to the IPR and increase the sum rate of the CRS. We further develop a spatial correlation-based resource sharing (SC-RS) strategy to improve energy sharing performance. CUs nearly orthogonal to the energy harvesting primary receiver (EPR) are chosen as candidates for user selection. Therefore, the EPR can harvest more energy from the CBS so that the energy utilization of the network can improve. Besides, zero-forcing precoding and power control are adopted to eliminate interference within the CRS and meet the transmit power constraints. Simulation results and analysis show that, compared with the existing CU selection methods, the proposed low-complex strategy can enhance both the achievable sum rate of the CRS and the energy sharing capability of the network.

Analysis of the Physical and Mechanical Properties of Injected High-Density Polyurethane from Laboratory Experiments and Field Tests (실내실험 및 현장실험을 통한 고밀도 폴리 우레탄 공법의 물리·역학적 특성 분석)

  • Choi, Junyoung;Kim, Daehyeon
    • The Journal of Engineering Geology
    • /
    • v.31 no.1
    • /
    • pp.83-101
    • /
    • 2021
  • The high-density polyurethane method uses the instantaneous expansion pressure of injected material to stabilize soft ground, allowing reinforcement, restoration, and construction to be carried out in suboptimal ground conditions. Under normal and, even poor conditions, the method is easily applied because the working time is very short. The method is environmentally friendly and results have excellent durability. The purpose of this study was to verify the physical and mechanical properties of high-density polyurethane in the ground. Initial testing of strength, direct shear, and soil environment stability was followed by testing for permeability in order to address environmental concerns. The results of the experiments showed that the internal friction angle was about twice as high and the adhesion was about 2.5 to 3.5 times higher than for dense and hard clay, and that the permeability factor was significantly lower compared with the existing grouting method, within the range of 1.0 × 10-5.

New therapeutic approach with extracellular vesicles from stem cells for interstitial cystitis/bladder pain syndrome

  • Dayem, Ahmed Abdal;Song, Kwonwoo;Lee, Soobin;Kim, Aram;Cho, Ssang-Goo
    • BMB Reports
    • /
    • v.55 no.5
    • /
    • pp.205-212
    • /
    • 2022
  • Interstitial cystitis/bladder pain syndrome (IC/BPS) is a debilitating chronic disorder characterized by suprapubic pain and urinary symptoms such as urgency, nocturia, and frequency. The prevalence of IC/BPS is increasing as diagnostic criteria become more comprehensive. Conventional pharmacotherapy against IC/BPS has shown suboptimal effects, and consequently, patients with end-stage IC/BPS are subjected to surgery. The novel treatment strategies should have two main functions, anti-inflammatory action and the regeneration of glycosaminoglycan and urothelium layers. Stem cell therapy has been shown to have dual functions. Mesenchymal stem cells (MSCs) are a promising therapeutic option for IC/BPS, but they come with several shortcomings, such as immune activation and tumorigenicity. MSC-derived extracellular vesicles (MSC-EVs) hold numerous therapeutic cargos and are thus a viable cell-free therapeutic option. In this review, we provide a brief overview of IC/BPS pathophysiology and limitations of the MSC-based therapies. Then we provide a detailed explanation and discussion of therapeutic applications of EVs in IC/BPS as well as the possible mechanisms. We believe our review will give an insight into the strengths and drawbacks of EV-mediated IC/BPS therapy and will provide a basis for further development.

Reinforced concrete structures with damped seismic buckling-restrained bracing optimization using multi-objective evolutionary niching ChOA

  • Shouhua Liu;Jianfeng Li;Hamidreza Aghajanirefah;Mohammad Khishe;Abbas Khishe;Arsalan Mahmoodzadeh;Banar Fareed Ibrahim
    • Steel and Composite Structures
    • /
    • v.47 no.2
    • /
    • pp.147-165
    • /
    • 2023
  • The paper contrasts conventional seismic design with a design that incorporates buckling-restrained bracing in three-dimensional reinforced concrete buildings (BRBs). The suboptimal structures may be found using the multi-objective chimp optimization algorithm (MEN-ChOA). Given the constraints and dimensions, ChOA suffers from a slow convergence rate and tends to become stuck in local minima. Therefore, the ChOA is improved by niching and evolutionary operators to overcome the aforementioned problems. In addition, a new technique is presented to compute seismic and dead loads that include all of a structure's parts in an algorithm for three-dimensional frame design rather than only using structural elements. The performance of the constructed multi-objective model is evaluated using 12 standard multi-objective benchmarks proposed in IEEE congress on evolutionary computation. Second, MEN-ChOA is employed in constructing several reinforced concrete structures by the Mexico City building code. The variety of Pareto optimum fronts of these criteria enables a thorough performance examination of the MEN-ChOA. The results also reveal that BRB frames with comparable structural performance to conventional moment-resistant reinforced concrete framed buildings are more cost-effective when reinforced concrete building height rises. Structural performance and building cost may improve by using a nature-inspired strategy based on MEN-ChOA in structural design work.

Anatomic coracoclavicular ligament reconstruction with triple flip-buttons leads to good functional outcomes and low reduction loss: a case series

  • Raul Aguila;Gonzalo Gana;J Tomas Munoz;Diego Garcia de la Pastora;Andres Oyarzun;Gabriel Mansilla;Sebastian Coda;J Tomas Rojas
    • Clinics in Shoulder and Elbow
    • /
    • v.26 no.2
    • /
    • pp.140-147
    • /
    • 2023
  • Background: The management of acromioclavicular (AC) joint dislocation remains controversial. Recently, anatomic coracoclavicular (CC) fixation with a double clavicular tunnel and three flip-buttons has shown promising results. This study aimed to evaluate functional and radiological outcomes in patients with high-grade AC joint dislocation treated with anatomic CC fixation using double clavicular tunnels and three flip-buttons. Methods: A retrospective, unicentric study was performed. The study included patients with high-grade AC joint dislocation who underwent surgery with anatomic CC fixation using double clavicular tunnels and three flip-buttons. Demographic data were obtained from medical records. A functional evaluation using subjective shoulder value (SSV), visual analog scale (VAS), and disabilities of the arm, shoulder, and hand (DASH) questionnaires was performed, and an evaluation of preoperative and postoperative comparative Zanca view images was performed. Factors associated with functional outcomes and radiological AC reduction were analyzed. Results: A total of 83 patients completed follow-up and were included in the analysis. The mean SSV, VAS, and DASH scores were 92.8, 0.8, and 6.4, respectively. Patients who had complications experienced significantly worse functional outcomes (DASH: P=0.037). Suboptimal final AC reduction was observed in nine patients (11.1%), and significantly more frequently in patients older than 40 years (P=0.031) and in surgeries performed more than 7 days after injury (P=0.034). There were two reoperations (2.4%). Conclusions: Anatomic CC fixation with a double clavicular tunnel and three flip-buttons leads to good functional outcomes, low complication rates, and high rates of optimal AC reduction.

In Vitro Development and Apoptosis in Haploid, Diploid Parthenotes and Fertilized Embryos

  • Y. J Chung;Lee, H. Y.;S. H. Jun;X. S. Cui;Kim, N. H.
    • Proceedings of the KSAR Conference
    • /
    • 2003.06a
    • /
    • pp.28-28
    • /
    • 2003
  • Haploid parthenotes have been shown to be developmentally delayed compared with diploid parthenogenetic embryos in the mouse and pig. These developmental defects have been hypothesized to rusult from insufficient parthenogenetic activation, suboptimal in vitro culture conditions, or genemic imprinting. In the present study we compared the incidence of apoptosis and apoptosis related gene expression in pig haploid, diploid parthenotes and fertilized embryos. In vitro matured porcine oocytes were activated by electrical stimulation. Haploid activated oocytes with two polar bodies under stereomicroscopy were defined haploid parthenotes, oocytes with one polar body were defined as diploid parthenotes after 3h cycloheximide teatment. The morphological analysis of apoptosis in embryos was carried out using propidium iodide staining and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling. The expression of Bcl-xL, Bak and P53 in haploid, diploid and in vivo fertilized blastocysts was determined using RT-PCR. Lower number of the haploid pig parthenotes developed to the morulae and blastocysts compared to the diploid parthnotes. Number of cells significantly lower in the haploid-derived blastocysts than diploid-derived it. Developmentally retarded haploid parthenotes exibited apoptosis at a significantly higher frequency than did diploid parthenotes and fertilized embryos. Level of Bcl-xL expression, diploid parthenotes similar to in vivo-derived it was higher than haploid parthenotes. However, Bak and P53 mRNA expression were not different among haploid, diploid, and fertilized embryos. This result suggested that parthenogenetic activation and parthenogenesis themselves do not cause apoptosis, but haploid increases the incidence of apoptosis in preimplantation embryos. Apoptosis may be due to decrease expression of Bcl-xL in haploid parthenotes developing in vitro.

  • PDF

Mitochondrial oxidative damage by co-exposure to bisphenol A and acetaminophen in rat testes and its amelioration by melatonin

  • Hina Rashid;Mohammad Suhail Akhter;Saeed Alshahrani;Marwa Qadri;Yousra Nomier;Maryam Sageer;Andleeb Khan;Mohammad F. Alam;Tarique Anwer;Razan Ayoub;Rana J. H. Bahkali
    • Clinical and Experimental Reproductive Medicine
    • /
    • v.50 no.1
    • /
    • pp.26-33
    • /
    • 2023
  • Objective: Human exposure to multiple xenobiotics, over various developmental windows, results in adverse health effects arising from these concomitant exposures. Humans are widely exposed to bisphenol A, and acetaminophen is the most commonly used over-the-counter drug worldwide. Bisphenol A is a well-recognized male reproductive toxicant, and increasing evidence suggests that acetaminophen is also detrimental to the male reproductive system. The recent recognition of male reproductive system dysfunction in conditions of suboptimal reproductive outcomes makes it crucial to investigate the contributions of toxicant exposures to infertility and sub-fertility. We aimed to identify toxicity in the male reproductive system at the mitochondrial level in response to co-exposure to bisphenol A and acetaminophen, and we investigated whether melatonin ameliorated this toxicity. Methods: Male Wistar rats were divided into six groups (n=10 each): a control group and groups that received melatonin, bisphenol A, acetaminophen, bisphenol A and acetaminophen, and bisphenol A and acetaminophen with melatonin treatment. Results: Significantly higher lipid peroxidation was observed in the testicular mitochondria and sperm in the treatment groups than in the control group. Levels of glutathione and the activities of catalase, glutathione peroxidase, glutathione reductase, and manganese superoxide dismutase decreased significantly in response to the toxicant treatments. Likewise, the toxicant treatments significantly decreased the sperm count and motility, while significantly increasing sperm mortality. Melatonin mitigated the adverse effects of bisphenol A and acetaminophen. Conclusion: Co-exposure to bisphenol A and acetaminophen elevated oxidative stress in the testicular mitochondria, and this effect was alleviated by melatonin.

Impact of nonphysician, technology-guided alert level selection on rates of appropriate trauma triage in the United States: a before and after study

  • Megan E. Harrigan;Pamela A. Boremski;Bryan R. Collier;Allison N. Tegge;Jacob R. Gillen
    • Journal of Trauma and Injury
    • /
    • v.36 no.3
    • /
    • pp.231-241
    • /
    • 2023
  • Purpose: Overtriage and undertriage rates are critical metrics in trauma, influenced by both trauma team activation (TTA) criteria and compliance with these criteria. Analysis of undertriaged patients at a level I trauma center revealed suboptimal compliance with existing criteria. This study assessed triage patterns after implementing compliance-focused process interventions. Methods: A physician-driven, free-text alert system was modified to a nonphysician, hospital dispatcher-guided system. The latter employed dropdown menus to maximize compliance with criteria. The preintervention period included patients who presented between May 12, 2020, and December 31, 2020. The postintervention period incorporated patients who presented from May 12, 2021, through December 31, 2021. We evaluated appropriate triage, overtriage, and undertriage using the Standardized Trauma Assessment Tool. Statistical analyses were conducted with an α level of 0.05. Results: The new system was associated with improved compliance with existing TTA criteria (from 70.3% to 79.3%, P=0.023) and decreased undertriage (from 6.0% to 3.2%, P=0.002) at the expense of increasing overtriage (from 46.6% to 57.4%, P<0.001), ultimately decreasing the appropriate triage rate (from 78.4% to 74.6%, P=0.007). Conclusions: This study assessed a workflow change designed to improve compliance with TTA criteria. Improved compliance decreased undertriage to below the target threshold of 5%, albeit at the expense of increased overtriage. The decrease in appropriate triage despite compliance improvements suggests that the current criteria at this institution are not adequately tailored to optimally balance the minimization of undertriage and overtriage. This finding underscores the importance of improved compliance in evaluating the efficacy of TTA criteria.