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1.
In this research, the three‐dimensional structural and colorimetric modeling of three‐dimensional woven fabrics was conducted for accurate color predictions. One‐hundred forty single‐ and double‐layered woven samples in a wide range of colors were produced. With the consideration of their three‐dimensional structural parameters, three‐dimensional color prediction models, K/S‐, R‐, and L*a*b*‐based models, were developed through the optimization of previous two‐dimensional models which have been reported to be the three most accurate models for single‐layered woven structures. The accuracy of the new three‐dimensional models was evaluated by calculating the color differences ΔL*, ΔC*, Δh°, and ΔECMC(2:1) between the measured and the predicted colors of the samples, and then the error values were compared to those of the two‐dimensional models. As a result, there has been an overall improvement in color predictions of all models with a decrease in ΔECMC(2:1) from 10.30 to 5.25 units on average after the three‐dimensional modeling. 相似文献
2.
PE Sipila VJ Wiebe GB Hubbard SK Koester VD Emshoff JU Maenpaa GT Wurz RC Seymour MW DeGregorio 《Canadian Metallurgical Quarterly》1993,(15):2138-2144
The effects of long-term tamoxifen exposure on cell growth and cell cycle kinetics were compared between oestrogen receptor (ER)-positive (MCF-7) and ER-negative (MDA-MB-231) cell lines. In the MCF-7 cell line, prolonged tamoxifen exposure (0.5 mumol/l for > 100 days) blocked cells in G0-G1 of the cell cycle, and slowed the doubling time of cells from 30 to 59 h. These effects corresponded to an increase in the cellular accumulation of tamoxifen over time [mean area under concentration curve (AUC) = 77.92 mumoles/10(6)/cells/day]. In contrast, in the MDA-MB-231 cell line, long-term tamoxifen exposure had no obvious effect on the doubling time, and reduced cellular tamoxifen accumulation (mean AUC = 50.50 mumoles/10(6)/cells/day) compared to the MCF-7 cells. Flow cytometric analysis of MDA-MB-231 cells demonstrated that a new tetraploid clone emerged following 56 days of tamoxifen exposure. Inoculation of the MDA-MB-231 tetraploid clone and MDA-MB-231 wildtype cells into the opposite flanks of athymic nude mice resulted in the rapid growth of tetraploid tumours. The tetraploid tumours maintained their ploidy following tamoxifen treatment for nine consecutive serial transplantations. Histological examination of the fifth transplant generation xenografts revealed that the tetraploid tumour had a 25-30 times greater mass, area of haemorrhage and necrosis, a slightly higher mitotic index and was more anaplastic than the control neoplasm. The control wildtype MDA-MB-231 tumours maintained a stable ploidy following tamoxifen treatment until the eighth and ninth transplantation, when a tetraploid population appeared, suggesting that tamoxifen treatment may select for this clone in vivo. These studies suggest that prolonged tamoxifen exposure may select for new, stable, fast growing cell clones in vitro as well as in vivo. 相似文献
3.
4.
Eunseok Song Yido Koo Yeon-Jae Jung Deok-Hee Lee Sangyoung Chu Soo-Ik Chae 《Solid-State Circuits, IEEE Journal of》2005,40(5):1094-1106
This paper describes a single-chip CMOS quad-band (850/900/1800/1900 MHz) RF transceiver for GSM/GPRS applications. It is the most important design issue to maximize resource sharing and reuse in designing the multiband transceivers. In particular, reducing the number of voltage-controlled oscillators (VCOs) required for local oscillator (LO) frequency generation is very important because the VCO and phase-locked loop (PLL) circuits occupy a relatively large area. We propose a quad-band GSM transceiver architecture that employs a direct conversion receiver and an offset PLL transmitter, which requires only one VCO/PLL to generate LO signals by using an efficient LO frequency plan. In the receive path, four separate LNAs are used for each band, and two down-conversion mixers are used, one for the low bands (850/900 MHz) and the other for the high bands (1800/1900 MHz). A receiver baseband circuit is shared for all four bands because all of their channel spaces are the same. In the transmit path, most of the building blocks of the offset PLL, including a TX VCO and IF filters, are integrated. The quad-band GSM transceiver that was implemented in 0.25-/spl mu/m CMOS technology has a size of 3.3/spl times/3.2 mm/sup 2/, including its pad area. From the experimental results, we found that the receiver provides a maximum noise figure of 2.9 dB and a minimum IIP3 of -13.2dBm for the EGSM 900 band. The transmitter shows an rms phase error of 1.4/spl deg/ and meets the GSM spectral mask specification. The prototype chip consumes 56 and 58 mA at 2.8 V in the RX and TX modes, respectively. 相似文献
5.
JM Bach H Otto GT Nepom G Jung H Cohen J Timsit C Boitard PM van Endert 《Canadian Metallurgical Quarterly》1997,10(4):375-386
Tissue composition and the distribution of body mass are described for four genera of East African Bovidae (Madoqua, Gazella, Damaliscus, Hippotragus) with supporting data from four others (Neotragus, Oryx, Tragelaphus, Connochaetes). These species are high in muscle mass, an adaptation convergent with other high-speed terrestrial cursors, bounders, and saltators. The segments below the elbow/cubitus and knee/stifle/genu joints in small bovids are both lighter in percent of total body mass (8.6% TBM) and less heavily muscled (10-15% of total limb musculature) than those segments in macaques (13.6% TBM, 20-25% of the limb musculature). Bovid species differ from one another in the regional distribution of muscle mass. Madoqua kirkii (4-5 kg) concentrates muscle in the lumbar extensors and hindlimbs; large species such as Damaliscus doreas (50-60 kg) and Hippotragus niger (160-220 kg) distribute it more evenly between the lumbar and cervical regions and between the hindlimbs and forelimbs. Gazella dorcas (10-20 kg) is quantitatively intermediate in those characteristics. The redistribution of muscle mass with increasing size correlates with the loss of axial bending of the vertebral column: in small, hindlimb dominant, 'dorsomobile' species such as Madoqua sagittal mobility increases stride length through 'extended' suspension; in large 'dorsostable' species such as Damaliscus and Hippotragus the vertebral column resists bending, consequently abbreviating or omitting this non-contact phase of the gait cycle. Locomotor adaptation as it is reflected in size, shape, and musculoskeletal structure is the key to habitat choice, dietary specialization, social structure, and male agonistic behavior and, therefore, central to the fabric of behavioral ecology. 相似文献
6.
Joonho Lim Kipaek Kwon Soo-Ik Chae 《Electronics letters》1998,34(4):344-346
The authors propose a reversible energy recovery logic (RERL) circuit for ultra-low-energy consumption, which consumes only adiabatic energy loss and leakage current loss by completely eliminating non-adiabatic energy loss. It is a dual-rail adiabatic circuit using the concept of reversible logic with a new eight-phase clocking scheme. Simulation results show that at low-speed operation, the RERL consumes much less energy than the complementary static CMOS circuit and other adiabatic logic circuits 相似文献
7.
ST O'Sullivan GT McGreal A Lyons L Burke JG Geoghegan MP Brady 《Canadian Metallurgical Quarterly》1994,47(9):851-852
A case of histologically confirmed Paget's disease of the breast in a 72 year old man, without underlying breast carcinoma, is reported. This report raises questions about the pathogenesis of this condition and suggests that Paget's disease is an independent, intraepidermal carcinoma rather than a direct extension of intraductal carcinoma of the breast to the nipple and areola. 相似文献
8.
We report two cases of successful pregnancy in women with chronic, infantile onset, or type II spinal muscular atrophy, both of whom delivered healthy, unaffected babies. The patients required concurrent management by a physiatrist, pulmonologist, and perinatologist throughout the pregnancy. Complications included recurrent urinary tract infections, dyspnea and worsening of pulmonary function, wheelchair seating and positioning problems, and musculoskeletal and low back pain. These problems resolved postpartum. One woman had vaginal delivery, the other had caesarean section, both of which were well-tolerated. Because of severe musculoskeletal deformity, pelvic assessment is necessary to determine the mode of delivery. The uterus has normal contractility and effective labor patterns can be established. Spinal/epidural anesthesia may be contraindicated because of spine deformity. The pregnancies had no deleterious effect on the progression of the disease in our patients, both of whom reported a positive experience with great personal fulfillment. 相似文献
9.
The pharmacological profile of a novel dual inhibitor, tepoxalin and of its carboxylic acid metabolite on cyclooxygenase and lipoxygenase pathways was evaluated by in vitro incubation with synovial tissue. Tissue specimens obtained at surgery in rheumatoid arthritis (RA, n = 10) or osteoarthritis (OA, n = 11) patients were incubated. Tepoxalin (10(-7), 10(-6), 10(-5) M) decreased eicosanoid release calculated in % of tyrode control for OA: LTC4 to 71-33%, 6-keto-PGF1a to 37-20%, PGE2 to 29-6%. For RA: LTC4 to 56-22%, 6-keto-PGF1a to 43-22%, PGE2 to 57-32%. Similarly, its metabolite (10(-7), 10(-5)M) decreased release in OA: LTC4 to 99 and 60%, PGE2 to 42 and 20%, 6-keto-PGF1a to 54 and 25%. In RA:LTC4 to 81 and 45%, PGE2 to 61 and 30%, 6-keto-PGF1a to 46 and 18%. Significance (P < 0.05) was achieved for all but 1 group (LTC4 metabolite at 10(-7)M vs tyrode). In summary a marked and dose dependent decrease of LT and PG release was obtained when incubating the dual inhibitor tepoxalin and its active carboxylic acid metabolite with synovial tissue at doses expected to be reached in the joint during therapy. 相似文献
10.
A technique for rebroadcasting of multiple broadband services in a clustered community served by a passive optical network is introduced. The scheme uses a common regenerator and utilises the existing fibre plant and customer units, reducing the infrastructure cost. 相似文献