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1.
Filip Sroubek Gabriel Cristóbal Jan Flusser 《IEEE transactions on image processing》2007,16(9):2322-2332
This paper presents a new approach to the blind deconvolution and superresolution problem of multiple degraded low-resolution frames of the original scene. We do not assume any prior information about the shape of degradation blurs. The proposed approach consists of building a regularized energy function and minimizing it with respect to the original image and blurs, where regularization is carried out in both the image and blur domains. The image regularization based on variational principles maintains stable performance under severe noise corruption. The blur regularization guarantees consistency of the solution by exploiting differences among the acquired low-resolution images. Several experiments on synthetic and real data illustrate the robustness and utilization of the proposed technique in real applications. 相似文献
2.
Although reticulocyte counts can be reliably performed for up to 48 h after storage in EDTA, it is unclear whether this is applicable to the pediatric age group. In order to evaluate this, manual reticulocyte counts were performed on 20 specimens from pediatric patients stored at 4 degrees C for up to 24 h post collection. Samples were evaluated at 1-3, 6, 12, 18, and 24 h after storage in EDTA vacutainer tubes at 4 degrees C. The age of the subjects ranged from 1 day to 9 years with a median age of 3 years. Patients' reticulocyte counts ranged from 0 to 27% (5.89 +/- 7.21). No clinically significant changes were evident in the reticulocyte count over 24 h after specimen collection. The mean of the 20 specimens at 1-3 h was 5.50 and at 24 h was 5.40 (P > .05). The standard deviation of the mean values ranged from 7.03 to 7.26 (P > .05). The results indicate that reticulocyte counts may be performed on previously drawn blood held at 4 degrees C for up to 24 h post collection in a pediatric population without significant difference from baseline values. 相似文献
3.
Interactions of metals and protons with algae 总被引:2,自引:0,他引:2
Crist RH Oberholser K Schwartz D Marzoff J Ryder D Crist DR 《Environmental science & technology》1988,22(7):755-760
4.
Amelia Zafra Cristóbal Romero Sebastián Ventura 《Expert systems with applications》2011,38(12):15020-15031
In this paper, a new approach based on multiple instance learning is proposed to predict student’s performance and to improve the obtained results using a classical single instance learning. Multiple instance learning provides a more suitable and optimized representation that is adapted to available information of each student and course eliminating the missing values that make difficult to find efficient solutions when traditional supervised learning is used. To check the efficiency of the new proposed representation, the most popular techniques of traditional supervised learning based on single instances are compared to those based on multiple instance learning. Computational experiments show that when the problem is regarded as a multiple instance one, performance is significantly better and the weaknesses of single-instance representation are overcome. 相似文献
5.
GK Rivera D Pinkel JV Simone ML Hancock WM Crist 《Canadian Metallurgical Quarterly》1993,329(18):1289-1295
BACKGROUND: Therapy for childhood lymphoblastic leukemia has evolved during the past three decades, but key questions about what are the least toxic, most effective forms of treatment remain unanswered because of the lack of comprehensive follow-up information. METHODS: To assess long-term outcome in the series of clinical trials conducted at St. Jude Hospital, we compared the results of treatment typical of four eras: exploratory combination chemotherapy (era 1, 1962 to 1966; 91 patients), regimens for the control of meningeal leukemia (era 2, 1967 to 1979; 825 patients), limited intensification of therapy (era 3, 1979 to 1983; 428 patients), and extended intensification of therapy (era 4, 1984 to 1988; 358 patients). ("Intensification" refers to strategies of systemic chemotherapy that are more aggressive than conventional ones.) The major end points were survival and event-free survival; we also calculated the relative risk of treatment failure and the rate of relapse or death after treatment ended (post-treatment failure rate). RESULTS: The probability of event-free survival improved significantly in each successive era (P < 0.001 by the log-rank test), reaching 71 percent in era 4. There was a decrease of approximately 50 percent in the risk of treatment failure from one era to the next in each subgroup of patients defined according to different combinations of the leukocyte count, race, age, and sex. Leukemia appeared to be eradicated in patients who remained in complete remission for three years or more after treatment in era 4. The incidence of death due to nonleukemic causes remained 4 to 6 percent despite the trend toward more intensive treatment. An estimated 765 patients (45 percent) are long-term survivors; most of them (80 percent) have no health problems related to leukemia or its treatment. CONCLUSIONS: The development and successful application of preventive therapy for meningeal leukemia, followed by the intensification of systemic chemotherapy, has progressively improved the rate of cure of childhood lymphoblastic leukemia, with relatively few adverse sequelae. 相似文献
6.
Cristèle Delsart Céline Cholet Rémy Ghidossi Nabil Grimi Etienne Gontier Laurence Gény Eugène Vorobiev Martine Mietton-Peuchot 《Food and Bioprocess Technology》2014,7(2):424-436
The treatment of Cabernet Sauvignon red grapes by pulsed electric fields (PEFs) is performed prior to vinification in order to enhance the extraction of polyphenols. PEF treatments of the longest duration and of the highest energy (E?= 0.7 kV/cm, t PEF?=?200 ms, W?=?31 Wh/kg) changed the structure of grape skins and produced a wine that was richer in tannins (34 %), while treatment of the highest strength (E?=?4 kV/cm, t PEF?=?1 ms, W =?4 Wh/kg) altered the visual appearance of phenolic compounds in the skins and led to greater extraction of the anthocyanins (19 %). The PEF treatments caused the depolymerization of skin tannins, improving the diffusion of these decondensed tannins which are smaller. The PEF treatment of longest duration and of the highest energy had more impact on the parietal tannins and the cell walls of the skins while treatment of the highest strength modified more the vacuolar tannins. Changes in the operating parameters of the PEF treatment (E?=?0.7 to 4 kV/cm, t PEF?=?1 to 200 ms, W?=?4 to 31 Wh/kg) did not affect alcohol content, total acidity nor volatile acidity in finished wines compared to the values of the control wine, but seemed to cause a slight increase in pH (1–2 %). 相似文献
7.
MM Hudson CA Poquette J Lee CA Greenwald A Shah X Luo EI Thompson JA Wilimas LE Kun WM Crist 《Canadian Metallurgical Quarterly》1998,16(11):3592-3600
PURPOSE: To determine the impact of treatment toxicity on long-term survival in pediatric Hodgkin's disease. PATIENTS AND METHODS: We studied late events in 387 patients treated for pediatric Hodgkin's disease on four consecutive clinical trials at St Jude Children's Research Hospital from 1968 to 1990. Relative risks, actuarial risks, and absolute excess risks for cause-specific deaths were calculated. RESULTS: As of April 1997, 316 (82%) of patients were alive, with a median follow-up of 15.1 (range, 2.9 to 28.6) years. In this cohort, which represented 5,623 person-years of follow-up, 71 fatal events resulted from Hodgkin's disease (n=36), second malignancies (n=14), infections (n=7), accidents (n=7), cardiac disease (n=6), and asphyxiation (n=1). The 5-year estimated event-free survival (EFS) for the entire cohort was 79.6%+/-2.1 %, which declined to 63.1%+/-4.4% by 20 years. Cumulative incidences of cause-specific deaths at 25 years were 9.8%+/-1.6% for Hodgkin's disease, 8.1%+/-2.6% for second malignancy, 4.0%+/-1.8% for cardiac disease, 3.9%+/-1.5% for infection, and 2.1%+/-0.8% for accidents. Standardized incidence ratios showed excess risk for all second malignancies (12; 95% confidence interval [CI], 8 to 17), acute myeloid leukemia (81; 95% CI, 16 to 237), solid tumors (11; 95% CI, 7 to 16), and breast cancer (33; 95% CI, 12 to 72). Standardized mortality ratios also showed excess mortality from cardiac disease (22; 95% CI, 8 to 48) and infection (18; 95% CI, 7 to 38). CONCLUSION: Compared with age- and sex-matched control populations, survivors of pediatric Hodgkin's disease who were treated before 1990 face an increased risk of early mortality related to second cancers, cardiac disease, and infection. 相似文献
8.
We extend the notion of randomness (in the version introduced by Schnorr) to computable probability spaces and compare it
to a dynamical notion of randomness: typicality. Roughly, a point is typical for some dynamic, if it follows the statistical behavior of the system (Birkhoff’s pointwise ergodic theorem). We prove that
a point is Schnorr random if and only if it is typical for every mixing computable dynamics. To prove the result we develop some tools for the theory of computable probability spaces (for example,
morphisms) that are expected to have other applications. 相似文献
9.
A total of 156 dairy cows was randomly assigned to one of four groups at drying off over an 18-mo period: untreated control or intramammary treatment of each mammary quarter with either 400 mg novobiocin, 300 mg cephapirin, or 1 g dihydrostreptomycin with 1 million units penicillin. Quarter foremilk samples were aseptically collected from each cow within 1 mo of drying off and within 1 mo after parturition for bacteriological analysis. Prior to drying off, 28.7% of quarters were positive of which 46.7% were Corynebacterium bovis and 45.5% were coagulase-negative staphylococci. Reductions in infection prevalence from drying off to postpartum samplings for control, novobiocin, cephapirin, and streptomycin-penicillin groups were 13.6, 60.5, 74.4, and 35.3% of quarters. Recovery rates for C. bovis infections were 47.6, 100, 100, and 94.1%; for coagulase-negative staphylococci infections they were 72.7, 86.4, 80.0, and 100%. The cephapirin group showed the lowest new infection rate (1.3%) with coagulase-negative staphylococci compared with control (6.9%). There were no significant differences in lactation milk production among groups following dry period therapy. Results suggest that dry treatment reduces the prevalence of infections by the minor mastitis pathogens. 相似文献
10.
Assembly lines can be employed successfully in sheltered work centres to better include persons with disabilities in the labour market as well as to improve production efficiency. The optimal assignment of a heterogeneous workforce is known as the assembly line worker assignment and balancing problem (ALWABP). These assembly lines are characterised not only by a heterogeneous workforce, but also by high levels of absenteeism, which makes it more difficult to obtain stable and efficient line balancing solutions. In this paper, an extension of the ALWABP to minimise the expected cycle time under uncertain worker availability is proposed. We model this problem as a two-stage mixed integer program, and propose local search heuristics for solving it. Computational experiments show that stochastic modelling can help to improve the line’s efficiency and that the proposed heuristics produce good results for instances of practical size. 相似文献