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1.
Abstract— The Helmholtz‐Kohlrausch (H‐K) effect is the influence of color purity on the perceived brightness of a color object (or source). In addition to a review of the effect, a survey of color and brightness‐perception studies from 1825 to the present (including our own studies on disabling glare) is presented. Disabling glare is the blinding experience which results from a bright source in our field of view. There has been a great deal of work on the H‐K effect, and this paper is our personal view of the subject. The H‐K effect has lead to new color‐appearance models which help to describe the brightness/luminance discrepancies, and we will only touch on this subject. It will be shown how the H‐K effect affects many of the displays, mobile devices, and phones. Additionally, how the H‐K effect is involved with our perception at mesopic light levels encountered during night driving will be discussed.  相似文献   
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Argues that Senator G. McGovern (see record 1970-16481-001) has a distorted view both of the idealism of youth and the situation in Vietnam, and that this idealism is rebellious, irresponsible, morally delinquent, and uninformed by religious/ethical values. (0 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Abstract: Pseudomonas fluorescens ATCC 13525 is used as the challenge organism to evaluate the efficacy of the clean‐in‐place (CIP) process of food equipment (automatic ice‐maker) as per NSF/ANSI Standard 12. Traditional culturing methodology is presently used to determine the concentration of the challenge organism, which takes 48 h to confirm the cell density. Storage of the challenge preparation in the refrigerator might alter the cell density as P. fluorescens is capable of growing at 4 °C. Also, background organism can grow on the Pseudomonas F agar (PFA) used for the recovery of P. fluorescens thus affecting the results of the test. Real‐time TaqMan assay targeting the cpn60 gene was developed for the enumeration and the identification of P. fluorescens because of its specificity, accuracy, and shorter turnaround time. The TaqMan primer‐probe pair developed using the Allele ID® 7.0 probe design software was highly specific and sensitive for the target organism. The sensitivity of the assay was 10 colony forming units (CFU)/mL. The assay was also successful in determining the concentration of the challenge preparation within 2 h. Based on these observations, TaqMan assay targeting the cpn60 gene can be efficiently used for strain level identification and enumeration of bacteria. Practical Application: Pseudomonas fluorescens ATCC 13525 is used as a challenge organism in the efficacy testing of clean‐in‐place process of food equipments. Currently, culturing technique is used for its identification and estimation, which is not only time‐consuming but also prone to error. Real‐time TaqMan assay is more specific, sensitive, and accurate along with a shorter turnaround time compared to culturing techniques, thereby increasing the overall quality of the testing methodology to evaluate the clean‐in‐place process critical for the food industry to protect public health and safety.  相似文献   
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A monoclonal antibody (antik-B) against an oligopeptide of 23 AA corresponding to the region 131-153 of bovine κ-casein (κ-CN) B was generated using the Human Combinatorial Antibody Library (HuCAL) technology. Both AA substitutions distinguishing κ-CN A and B are located in that region (positions 136 and 148). In this study, the reactivity of antik-B to milk samples collected from cows previously genotyped as CSN3*AA, CSN3*AB, and CSN3*BB was tested. According to Western blot results, antik-B recognized κ-CN B and it showed no cross-reactivity toward κ-CN A and other milk proteins. Furthermore, a modified Western blot method, urea-PAGE Western blot, was set up to assess the reactivity of antik-B toward all isoforms of κ-CN B. In conclusion, antik-B was specific to κ-CN B in milk and it seemed to be reactive toward all its isoforms.  相似文献   
6.
Experimental infection with the gamma-herpesvirus bovine herpesvirus 4 (BoHV-4) rarely establishes disease, yet BoHV-4 is commonly associated with uterine disease in cattle. Uterine disease involves co-infection with bacteria such as Escherichia coli, which stimulate the production of prostaglandin E(2) (PGE(2)) by endometrial cells. BoHV-4 replication depends on immediate early 2 (IE2) gene transactivation and, in the present study, PGE(2), E. coli or its lipopolysaccharide upregulated the IE2 gene promoter in uterine cells. Bacterial co-infection is important for BoHV-4 uterine disease.  相似文献   
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We report herein on the first serological detection of antibodies to bovine immunodeficiency virus (BIV) in Italy. According to criteria of a stratified-random sampling of dairy cattle reared in the Parma area (a province in the Po Valley, Northern Italy), sera from 3166 cows belonging to 272 herds were collected. In addition, sera of 138 bulls from eight artificial-insemination (AI) centres were sampled. Seventy-eight cows (2.5%) from 16 herds (5.8%) and seven bulls (5.1%) from two AI centres were positive for BIV-R29 antibodies in the IFA-test. IFA-positive sera assayed by Western blot had reaction to different viral proteins: 81 out of 85 sera showed antibody to p26 (considered the BIV major internal core protein); four sera reacted to other viral proteins but not to p26. Peripheral blood leukocytes of 60 seropositive and 60 seronegative animals, belonging to eight BIV-infected herds, were enumerated to assess any effect of BIV infection on white-blood cells. No significant differences were detected between the two groups. These data indicate that BIV infection is present in Italian dairy cattle--but the role of BIV in inducing disease remains unclear.  相似文献   
8.
Bovine postpartum uterine disease, metritis, affects about 40% of animals and is widely considered to have a bacterial aetiology. Although the gamma-herpesvirus bovine herpesvirus 4 (BoHV-4) has been isolated from several outbreaks of metritis or abortion, the role of viruses in endometrial pathology and the mechanisms of viral infection of uterine cells are often ignored. The objectives of the present study were to explore the interaction, tropism and outcomes of BoHV-4 challenge of endometrial stromal and epithelial cells. Endometrial stromal and epithelial cells were purified and infected with a recombinant BoHV-4 carrying an enhanced green fluorescent protein (EGFP) expression cassette to monitor the establishment of infection. BoHV-4 efficiently infected both stromal and epithelial cells, causing a strong non-apoptotic cytopathic effect, associated with robust viral replication. The crucial step for the BoHV-4 endometriotropism appeared to be after viral entry as there was enhanced transactivation of the BoHV-4 immediate early 2 gene promoter following transient transfection into the endometrial cells. Infection with BoHV-4 increased cyclooxygenase 2 protein expression and prostaglandin estradiol secretion in endometrial stromal cells, but not epithelial cells. Bovine macrophages are persistently infected with BoHV-4, and co-culture with endometrial stromal cells reactivated BoHV-4 replication in the persistently infected macrophages, suggesting a symbiotic relationship between the cells and virus. In conclusion, the present study provides evidence of cellular and molecular mechanisms, supporting the concept that BoHV-4 is a pathogen associated with uterine disease.  相似文献   
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To prevent barotitis during descent in aviation, the ears have to be cleared several times by performing the Valsalva's manoeuvre. The manoeuvre is difficult for children to perform, and they are therefore at high risk of developing barotitis. The treatment of barotitis is either inflation by a Politzer balloon or myringotomy. An alternative treatment is autoinflation using the Otovent. This prophylaxis/treatment can be performed by the child with assistance from its parents as soon as or preferably before the descent has started. The prevalence of barotitis amongst 45 children and 49 adults in transit was found to be highest in children, 28%, compared with adults, 10%. Only 6% of the children with negative middle ear pressure after flight managed a successful Valsalva manoeuvre, whereas 33% could normalise the middle ear pressure by inflating the Otovent. In conclusion we recommend autoinflation using the Otovent set by children and adults who have problems clearing their ears during flight.  相似文献   
10.
BACKGROUND: Superior cavopulmonary connection reduces the volume work of the single ventricle. METHODS: To determine the effects of superior cavopulmonary connection on preload, wall stress (or afterload), and systolic ventricular function, we studied 9 patients before and after operation, and at hospital discharge. Using echocardiography, preload was estimated by the ventricular end-diastolic area, and wall stress was calculated at end-systole and peak-systole. Ventricular function was represented by rate-corrected velocity of circumferential fiber shortening and fractional area change divided by rate-corrected ejection time. RESULTS: End-diastolic area and wall stress decreased postoperatively. Ventricular wall thickness increased with a concomitant decrease in cavity area. There was no change in mean blood pressure or heart rate or in rate-corrected velocity of circumferential fiber shortening or fractional area change divided by rate-corrected ejection time. These findings persisted at hospital discharge. CONCLUSIONS: In single ventricles, superior cavopulmonary correction results in an immediate decrease in preload and afterload. The decrease in afterload results primarily from alterations in ventricular geometry. Although no improvement in systolic function was noted, diminished work related to the reduction in loading conditions may have beneficial long-term effects on preserving myocardial performance.  相似文献   
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