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Many early stage human tumors display markers of a DNA-damage response (DDR), including ataxia telangiectasia mutated (ATM) kinase activation. This suggests that DNA damage accumulates during the process of carcinogenesis and that the ATM-dependent response to this damage may function to suppress cancer progression. The E2F3a transcription factor plays an important role in regulating cell proliferation and is amplified in a subset of human cancers. Similar to human premalignant lesions, we find activated ATM and other markers of the DDR in the hyperplastic epidermis of transgenic mice expressing E2F3a through a keratin 5 (K5) promoter. Primary keratinocytes from K5 E2F3a transgenic mice contain increased levels of DNA breaks compared to wild-type cells. E2F3a overexpression also induced DNA damage in primary human fibroblasts that was inhibited by blocking DNA replication. The absence of ATM impaired apoptosis induced by E2F3a and treating K5 E2F3a transgenic mice with caffeine, an inhibitor of ATM and Rad3-related (ATR), promoted skin tumor development. These findings demonstrate that the deregulated expression of E2F3a causes DNA damage under physiological conditions and indicate that the ATM-dependent response to this damage is important for the induction of apoptosis and tumor suppression.

Three corn hybrids (Pioneer 36F30, Mycogen TMF2450, and Mycogen TMF2404) were compared for yield and quality traits, and lactation performance and apparent digestibility by Holstein cows. The three corn silages were harvested at a target of 33 to 35% dry matter. Before harvest, six corn plants were randomly selected for plant fractionation. Grain-to-stover ratios were 0.92, 0.70, and 0.95 for the 36F30, TMF2450, and TMF2404 corn plants, respectively. Fifty-two multiparous Holstein cows were placed on a 120-d lactation trial after a 21-d covariate diet. Cows were blocked by calving date and randomly assigned within block to one of three dietary treatments, containing approximately 40% (dry matter basis) corn silage. Milk yield, milk components, and dry matter intake did not differ among dietary treatments. In vitro true and neutral detergent fiber digestibilities were numerically higher for TMF2404 than the other corn silage hybrids. Apparent total-tract crude protein and neutral detergent fiber digestibilities, as measured by acid insoluble ash, were higher for TMF2450 than the other two hybrids, but starch digestibility was not different between the corn silage dietary treatments. Although small differences in nutrient content and digestibility existed among corn silage hybrids, inclusion of these leafy hybrids in lactating cow diets at 40% of the dietary dry matter did not have a significant impact on lactation performance of dairy cattle.

Jersey×Holstein crossbreds (J×H; n=76) were compared with pure Holsteins (n=73) for 305-d milk, fat, and protein production; conception rate; days open; proportion of cows pregnant within fixed intervals postpartum; and body and udder measurements during first lactation. Cows were housed at 2 research locations of the University of Minnesota and calved from September 2003 to May 2005. The J×H were mated to Montbeliarde sires, and Holstein cows were mated to Holstein sires. Best Prediction was used to determine actual production (milk, fat, and protein) for 305-d lactations with adjustment for age at calving, and records less than 305 d were projected to 305 d. The J×H (274kg) and pure Holsteins (277kg) were not significantly different for fat production, but J×H had significantly less milk (7,147 vs. 7,705kg) and protein (223 vs. 238kg) production than pure Holsteins. The J×H had significantly fewer days open than pure Holsteins (127 vs. 150 d). Also, a significantly greater proportion of J×H were pregnant at 150 and 180 d postpartum than pure Holsteins (75 vs. 59% and 77 vs. 61%, respectively). The J×H had significantly less body weight (60kg) at calving, but significantly greater body condition (2.80 vs. 2.71). Furthermore, J×H had significantly less udder clearance from the ground to the bottom of the udder than pure Holsteins (47.7 vs. 54.6cm), and greater distance between front teats (15.8 vs. 14.0cm) than pure Holsteins during first lactation.

We have measured directly the rate of formation of the oxidized chlorophyll a electron donor (P680+) and the reduced electron acceptor pheophytin a- (Pheoa-) following excitation of isolated spinach photosystem II reaction centers at 4 degrees C. The reaction-center complex consists of D1, D2, and cytochrome b-559 proteins and was prepared by a procedure that stabilizes the protein complex. Transient absorption difference spectra were measured from 440 to 850 nm as a function of time with 500-fs resolution following 610-nm laser excitation. The formation of P680+-Pheoa- is indicated by the appearance of a band due to P680+ at 820 nm and corresponding absorbance changes at 505 and 540 nm due to formation of Pheoa-. The appearance of the 820-nm band is monoexponential with τ = 3.0 ± 0.6 ps. The time constant for decay of 1*P680, the lowest excited singlet state of P680, monitored at 650 nm, is τ = 2.6 ± 0.6 ps and agrees with that of the appearance of P680+ within experimental error. Treatment of the photosystem II reaction centers with sodium dithionite and methyl viologen followed by exposure to laser excitation, conditions known to result in accumulation of Pheoa-, results in formation of a transient absorption spectrum due to 1*P680. We find no evidence for an electron acceptor that precedes the formation of Pheoa-.

Jersey x Holstein crossbred (JxH) cows (n = 24) were compared with pure Holstein cows (n = 17) for body weight, body condition score, dry matter intake (DMI), and feed efficiency during the first 150 d of first lactation. Cows were housed in the University of Minnesota dairy facility at the St. Paul campus and calved from September 2004 to January 2005. The JxH cows were mated by artificial insemination with Montbeliarde bulls, and Holstein cows were mated by artificial insemination with Holstein bulls. Cows were weighed and body condition was scored every other week. Cows were individually fed a TMR twice daily, and feed refusals were measured once daily. The DMI of cows was measured daily and averaged across 7-d periods. Milk production and milk composition were from monthly Dairy Herd Improvement records. Best Prediction was used to calculate actual production (milk, fat, protein) for each cow from the 4th to 150th day of first lactation. The JxH cows had significantly less body weight (467 vs. 500 kg) and significantly higher body condition scores (2.90 vs. 2.76) than pure Holstein cows. The JxH cows had significantly less milk production (4,388 vs. 4,644 kg) during the 4th to 150th day of lactation than did pure Holstein cows. However, fat plus protein production during the first 150 d of lactation was not significantly different for JxH (302 kg) and Holstein (309 kg) cows. The JxH and pure Holstein cows did not differ significantly for daily DMI (22.0 vs. 22.7 kg, respectively), and the JxH (4.7%) and pure Holstein (4.5%) cows consumed similar DMI based on percentage of body weight. Consequently, feed efficiency for the 4th to 150th day of lactation did not differ for JxH and pure Holstein cows.

Business students and professionals need the ability to think statistically about how to deal with uncertainty and its effect on decision-making in management and commerce. Traditional statistics texts tend to focus on probability, mathematical detail, and heavy computation, and thus fail to meet the needs of future business managers. Statistical Thinking in Business provides an introductory course in business statistics for those with little mathematical background. This new edition removes the 'workbook' approach to make room for more material with greater emphasis on forecasting and time series. A supporting Web site provides a wealth of supplemental materials.

Variation. Problem Solving. Looking at Data. Modeling Data. Attribute Data. Sampling. Estimation. Regression Analysis. Multiple Regression. Forecasting. Statistical Process Control. Control Charts. Improvement Strategies. Postscript. Introduction to Excel