• Title/Summary/Keyword: 0/1 constraint

Search Result 170, Processing Time 0.023 seconds

Indigenous Fungivorous Nematodes Affect the Biocontrol Efficacy of Trichoderma harzianum through Reducing the Hyphal Density

  • Kim, Tae Gwan;Knudsen, Guy R.
    • Journal of Microbiology and Biotechnology
    • /
    • v.31 no.6
    • /
    • pp.815-822
    • /
    • 2021
  • Indigenous fungus-feeding nematodes may adversely affect the growth and activity of introduced biocontrol fungi. Alginate pellets of the biocontrol fungus Trichoderma harzianum ThzID1-M3 and sclerotia of the fungal plant pathogen Sclerotinia sclerotiorum were added to nonsterile soil at a soil water potential of -50 or -1,000 kPa. The biomass of ThzID1-M3, nematode populations, and extent of colonization of sclerotia by ThzID1-M3 were monitored over time. The presence of ThzID1-M3 increased the nematode population under both moisture regimes (p < 0.05), and fungivores comprised 69-75% of the nematode population. By day 5, the biomass of ThzID1-M3b and its colonization of sclerotia increased and were strongly correlated (R2 = 0.98), followed by a rapid reduction, under both regimes. At -50 kPa (the wetter of the two environments), fungal biomass and colonization by ThzID1-M3 were less, in the period from 5 to 20 days, while fungivores were more abundant. These results indicate that ThzID1-M3 stimulated the population growth of fungivorous nematodes, which in turn, reduced the biocontrol ability of the fungus to mycoparasitize sclerotia. However, colonization incidence reached 100% by day 5 and remained so for the experimental period under both regimes, although hyphal fragments disappeared by day 20. Our results suggest that indigenous fungivores are an important constraint for the biocontrol activity of introduced fungi, and sclerotia can provide spatial refuge for biocontrol fungi from the feeding activity of fungivorous nematodes.

Simulation of Dynamic Behavior of Glucose- and Tryptophan-Grown Escherichia coli Using Constraint-Based Metabolic Models with a Hierarchical Regulatory Network

  • Lee Sung-Gun;Kim Yu-Jin;Han Sang-Il;Oh You-Kwan;Park Sung-Hoon;Kim Young-Han;Hwang Kyu-Suk
    • Journal of Microbiology and Biotechnology
    • /
    • v.16 no.6
    • /
    • pp.993-998
    • /
    • 2006
  • We earlier suggested a hierarchical regulatory network using defined modeling symbols and weights in order to improve the flux balance analysis (FBA) with regulatory events that were represented by if-then rules and Boolean logic. In the present study, the simulation results of the models, which were developed and improved from the previou model by incorporating a hierarchical regulatory network into the FBA, were compared with the experimental outcome of an aerobic batch growth of E. coli on glucose and tryptophan. From the experimental result, a diauxic growth curve was observed, reflecting growth resumption, when tryptophan was used as an alternativee after the supply of glucose was exhausted. The model parameters, the initial concentration of substrates (0.92 mM glucose and 1 mM tryptophan), cell density (0.0086 g biomass/1), the maximal uptake rates of substrates (5.4 mmol glucose/g DCW h and 1.32 mmol tryptophan/g DCW h), and lag time (0.32 h) were derived from the experimental data for more accurate prediction. The simulation results agreed with the experimental outcome of the temporal profiles of cell density and glucose, and tryptophan concentrations.

Optimum Design of Composite Framed Structures Based Reliability Index (신뢰성지수를 고려한 합성 뼈대구조물의 최적설계에 관한 연구)

  • Jung, Young Chae;Kim, Jong Gil
    • Journal of Korean Society of Steel Construction
    • /
    • v.15 no.4 s.65
    • /
    • pp.389-401
    • /
    • 2003
  • The purpose of this study is to develop an algorithm, which can be designed the optimal sections of the composite framed structures constituted with the beams and the columns consisted of H type of steel section and concrete considering the reliability index. The optimized problem or the composite framed structures is formulated with the objective function and the constraints taking the section sizes as the design variables. The objective functions are constituted by the total costs of constructions. Also, the constraints are derived by considering the reliability index of section stress and allowable stress. The algorithm optimized the section of the composite framed structures utilizes the SUMT method using the modified Newton-Raphson direction method. The optimizing algorithm developed in this study is applied to the numerical examples with respecting a one-bay, one-story composite framed structure and a one-bay five-story one for the practical utilization of design on the composite framed structures using the reliability indices$({\beta})$ three and zero. In addition, their numerical results are compared and analyzed to examine the possibility of optimization the applicability, and the convergence this algorithm.

Differential Selection by Nematodes of an Introduced Biocontrol Fungus vs. Indigenous Fungi in Nonsterile Soil

  • Kim, Tae Gwan;Knudsen, Guy R.
    • Journal of Microbiology and Biotechnology
    • /
    • v.28 no.5
    • /
    • pp.831-838
    • /
    • 2018
  • Trophic interactions of introduced biocontrol fungi with soil animals can be a key determinant in the fungal proliferation and activity. This study investigated the trophic interaction of an introduced biocontrol fungus with soil nematodes. The biocontrol fungus Trichoderma harzianum ThzID1-M3 and the fungivorous nematode Aphelenchoides sp. (10 per gram of soil) were added to nonsterile soil, and microbial populations were monitored for 40 days. Similar results were obtained when the experiment was duplicated. ThzID1-M3 stimulated the population growth of indigenous nematodes (p < 0.05), regardless of whether Aphelenchoides sp. was added. Without ThzID1-M3, indigenous nematodes did not increase in number and the added Aphelenchoides sp. nematodes almost disappeared by day 10. With ThzID1-M3, population growth of nematodes was rapid between 5 and 10 days after treatment. ThzID1-M3 biomass peaked on day 5, dropped at day 10, and then almost disappeared at day 20, which was not influenced by the addition of nematodes. In contrast, a large quantity of ThzID1-M3 hyphae were present in a heat-treated soil in which nematodes were eliminated. Total fungal biomass in all treatments peaked on day 5 and subsequently decreased. Addition of nematodes increased the total fungal biomass (p < 0.05), but ThzID1-M3 addition did not affect the fungal biomass. Hyphae of total fungi when homogenously distributed did not support the nematode population growth; however, hyphae of the introduced fungus did when densely localized. The results suggest that soil fungivorous nematodes are an important constraint on the hyphal proliferation of fungal agents introduced into natural soils.

Design of Miniaturization Terminal Antenna for 2.4 GHz WiFi Band with MZR (MZR을 이용한 2.4 GHz WiFi 대역 소형 단말기 안테나 설계)

  • Lee, Young-Hun
    • Journal of IKEEE
    • /
    • v.23 no.1
    • /
    • pp.14-21
    • /
    • 2019
  • In this paper, we implemented an on-board miniaturization antenna operating 2.4 GHz using MZR(Mu Zero Resonator). It is must be operating under the constraint that the size of the small terminal PCB should be $78{\times}38{\times}0.8mm^3$ and the size of the system should be $63{\times}38{\times}0.8mm^3$ and the size of the radiating part should be $15{\times}38{\times}0.8mm^3$. The feeding structure uses a CPW structure for stable feeding and a feeding point at the upper left of the system board. A magnetic field coupling structure is used for coupling the feeding part and the antenna. The resonance frequency of the MZR is determined by the series inductance and capacitance of the cell, so the gap between the cells, the length of the cell, the length of the interdigital capacitor, and the spacing between the radiation part and the ground plane are analyzed. The antenna was designed and fabricated using the results. The total size of the antenna including the feed structure is $20.8{\times}9.0{\times}0.8mm^3$, and the electrical length is $0.1664{\lambda}_0{\times}0.072{\lambda}_0{\times}0.0064{\lambda}_0$. The measurement result for 10 dB bandwidth, gain and directivity are 440 MHz(18.3%), 0.4405 dB, and 2.722 dB respectively. It is confirmed that the radiation pattern has omnidirectional characteristics and it can be applied to ultra small terminal antenna.

The Effects of mCIMT using PNF on the Upper Extremity Function and Activities of Daily Living in Patients with Subacute Stroke (고유수용성촉진법을 이용한 수정된 강제유도 운동치료가 아급성 뇌졸중 환자의 상지 기능과 일상생활수행능력에 미치는 영향)

  • Bang, Dae-Hyouk;Song, Myung-Soo;Cho, Hyuk-Shin
    • PNF and Movement
    • /
    • v.16 no.3
    • /
    • pp.451-460
    • /
    • 2018
  • Purpose: The purpose of this study was to investigate the effects of a modified constraint induced movement therapy (mCIMT) using proprioceptive neuromuscular facilitation (PNF) on the upper extremity function and activities of daily living (ADLs) in patients with subacute stroke. Methods: Fourteen participants with subacute stroke were randomly assigned to a group using both mCIMT and PNF or a group using mCIMT alone. Each group underwent twenty sessions (1 h/d, 5 d/wk) for 4 weeks. Patients were assessed with the action research arm test (ARAT), the Fugl-Meyer assessment for the upper extremities (FMA-UE), the Modified Barthel Index (MBI), and motor activity logs (MALs; amount of use [AOU] and quality of movement [QOM]). Results: Both the experimental group and the control group showed significant intragroup improvement in the ARAT, FMA-UE, MBI, and MAL-AOU (p<0.05). The group using both mCIMT and PNF exhibited greater improvement in the ARAT, FMA-UE, MBI, and MAL-AOU than did the group using mCIMT alone. Statistical analyses showed significant differences in the ARAT (p=0.01), FMA-UE (p=0.01), MBI (p=0.00), and MAL-AOU (p=0.01) between the groups. Conclusion: This study applied mCIMT combined with PNF for subacute stroke patients, and the results showed significant improvements in the patients' upper extremity function and ADLs. Therefore, mCIMT using PNF may be more effective than mCIMT alone in improving upper limb function and ADLs in patients with subacute stroke.

Iterative Reduction of Blocking Artifact in Block Transform-Coded Images Using Wavelet Transform (웨이브렛 변환을 이용한 블록기반 변환 부호화 영상에서의 반복적 블록화 현상 제거)

  • 장익훈;김남철
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.24 no.12B
    • /
    • pp.2369-2381
    • /
    • 1999
  • In this paper, we propose an iterative algorithm for reducing the blocking artifact in block transform-coded images by using a wavelet transform. In the proposed method, an image is considered as a set of one-dimensional horizontal and vertical signals and one-dimensional wavelet transform is utilized in which the mother wavelet is the first order derivative of a Gaussian like function. The blocking artifact is reduced by removing the blocking component, that causes the variance at the block boundary position in the first scale wavelet domain to be abnormally higher than those at the other positions, using a minimum mean square error (MMSE) filter in the wavelet domain. This filter minimizes the MSE between the ideal blocking component-free signal and the restored signal in the neighborhood of block boundaries in the wavelet domain. It also uses local variance in the wavelet domain for pixel adaptive processing. The filtering and the projection onto a convex set of quantization constraint are iteratively performed in alternating fashion. Experimental results show that the proposed method yields not only a PSNR improvement of about 0.56-1.07 dB, but also subjective quality nearly free of the blocking artifact and edge blur.

  • PDF

A PCA-based MFDWC Feature Parameter for Speaker Verification System (화자 검증 시스템을 위한 PCA 기반 MFDWC 특징 파라미터)

  • Hahm Seong-Jun;Jung Ho-Youl;Chung Hyun-Yeol
    • The Journal of the Acoustical Society of Korea
    • /
    • v.25 no.1
    • /
    • pp.36-42
    • /
    • 2006
  • A Principal component analysis (PCA)-based Mel-Frequency Discrete Wavelet Coefficients (MFDWC) feature Parameters for speaker verification system is Presented in this Paper In this method, we used the 1st-eigenvector obtained from PCA to calculate the energy of each node of level that was approximated by. met-scale. This eigenvector satisfies the constraint of general weighting function that the squared sum of each component of weighting function is unity and is considered to represent speaker's characteristic closely because the 1st-eigenvector of each speaker is fairly different from the others. For verification. we used Universal Background Model (UBM) approach that compares claimed speaker s model with UBM on frame-level. We performed experiments to test the effectiveness of PCA-based parameter and found that our Proposed Parameters could obtain improved average Performance of $0.80\%$compared to MFCC. $5.14\%$ to LPCC and 6.69 to existing MFDWC.

Novel Approaches to Clubroot Management in Western Canada

  • Hwang, Sheau-Fang;Strelkov, Stephen E.
    • 한국균학회소식:학술대회논문집
    • /
    • 2015.05a
    • /
    • pp.49-49
    • /
    • 2015
  • Over the past decade, clubroot has emerged as a major constraint to canola (Brassica napus) production in central Alberta, Canada. The number of fields with confirmed P. brassicae infestations in Alberta has increased steadily from 12 in 2003 to nearly 2,000 in 2014. Management of clubroot on canola has focused on sanitization of field equipment, soil amendments to reduce viable pathogen populations, long rotations out of susceptible crops and cropping of resistant cultivars. Clubroot resistance is the most effective and economical method of disease mitigation, but the recent identification of isolated P. brassicae populations with novel virulence phenotypes capable of overcoming resistance in most canola cultivars highlights the variable nature and adaptability of the pathogen. Recent studies have shown slight reductions in pathogen populations through crop rotations, but much more substantial reductions in spore populations in heavily infested areas near field entrances using fumigants such as Vapam (metam-sodium) or Basamid (dazomet). Greenhouse trials showed that seedling emergence, plant height and root weight increased, while primary and secondary infection and disease severity decreased with increased Basamid dosage. However, field trials showed some phytotoxicity. Application of Vapam at rates of 0.4 to $1.6mL\;L^{-1}$ soil resulted in 12-16 fold reductions in clubroot severity and primary and secondary infection. Vapam also was effective in reducing clubroot severity and improving canola seed yield under field conditions. These studies underscore the need for good resistance stewardship and for the integration of multiple products and practices for successful management of clubroot on canola.

  • PDF

Model verification and assessment of shear-flexure interaction in pile foundations

  • Lemnitzer, Anne;Nunez, Eduardo;Massone, Leonardo M.
    • Earthquakes and Structures
    • /
    • v.11 no.1
    • /
    • pp.141-163
    • /
    • 2016
  • Fiber models have been developed and applied to various structural elements such as shear walls, beams and columns. Only scarcely have fiber models been applied to circular foundation systems such as cast in drilled holes shafts (CIDH). In pile foundations with constraint head boundary conditions, shear deformations can easily contribute to the lateral pile response. However, soil structure interaction formulations such as the p-y method, commonly used for lateral pile design, do not include structural shear deformations in its traditional derivation method. A fiber model that couples shear and axial-bending behavior, originally developed for wall elements was modified and validated on circular cross sections (columns) before being applied to a 0.61 m diameter reinforced concrete (RC) pile with fixed head boundary conditions. The analytical response was compared to measured test results of a fixed head test pile to investigate the possible impact of pile shear deformations on the displacement, shear, and moment profiles of the pile. Results showed that shear displacements and forces are not negligible and suggest that nonlinear shear deformations for RC piles should be considered for fixed-head or similar conditions. Appropriate sensor layout is recommended to capture shear deformation when deriving p-y curves from field measurements.