History and Biography:

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Quantifying resilience of humans and other animals

All life requires the capacity to recover from challenges that are as inevitable as they are unpredictable. Understanding this resilience is essential for managing the health of humans and their livestock. It has long been difficult to quantify resilience directly, forcing practitioners to rely on indirect static indicators of health. However, measurements from wearable electronics and other sources now allow us to analyze the dynamics of physiology and behavior with unsurpassed resolution. The resulting flood of data coincides with the emergence of novel analytical tools for estimating resilience from the pattern of micro-recoveries observed in natural time series. Such dynamic indicators of resilience (DIORs) may be used to monitor the risk of systemic failure across systems ranging from organs to entire organisms. These tools invite a fundamental rethink of our approach to the adaptive management of health and resilience

Drawing Of Cityscape

ca. 1985Ink/board; 40" x 30"Part of the Archives' Visual Materials collectio

Changing And Controlling The "First Critical Speed" Of Overhung Centrifugal Fans.

LecturePg. 33-40Nine 150 hp centrifugal fans with overhung 40 inch diameter wheels pull hot air through the spray dryer bag houses (SDBH) in the finishing area of a titanium dioxide (TiO2) plant in New Johnsonville, Tennessee. The fans had operated for years at 900 rpm, but in 1998, with the fan manufacturer’s agreement, their operating speed was increased to 2080 rpm. Following this change, several of the fans experienced high vibration and became balance sensitive, and two fans wrecked catastrophically after bearings failed. Operation on or near the “first lateral critical speed” was suspected; however, before the speed was increased, the fan manufacturer had reported the “critical speed” of the fan as 3000 rpm. Through a combination of extensive testing and rotordynamics analysis by the end user, it was determined that the actual “first critical speed” of the nine fans varied from as low as 1700 rpm to no higher than 2405 rpm, straddling the 2080 rpm operating speed. This paper presents the results of the extensive analysis, explaining: *Why the large discrepancy between reported and actual first critical speeds, * How the actual first critical speeds were determined, *What factors contributed to such a large range of critical speeds, *What was changed to move the first critical speeds away from operating speed, *How much did each change accomplish, and *What control process was put in place to assure that when new fans are installed, the first critical speed will not be a problem. The program at the New Johnsonville plant has been a success and fans that once were the number one maintenance issue have since been removed from the “constant headache” list. In fact, one mechanic commented recently: “We just don’t work on those fans anymore.

Microsoft Word - 100909upd

Abstract: The ability to appropriately respond to proteotoxic stimuli is a major determinant of longevity and involves induction of various heat shock response (HSR) genes, which are essential to cope with cellular and organismal insults throughout lifespan. The activity of NAD+-dependent deacetylase Sir2, originally discovered in yeast, is known to be essential for effective HSR and longevity. Our previous work on HSR in Daphnia pulicaria indicated a drastic reduction of the HSR in older organisms. In this report we investigate the role of Sir2 in regulating HSR during the lifespan of D. pulicaria. We cloned Daphnia Sir2 open reading frame (ORF) to characterize the enzyme activity and confirmed that the overall function of Sir2 was conserved in Daphnia. The Sir2 mRNA levels increased while the enzyme activity declined with age and considering that Sir2 activity regulates HSR, this explains the previously observed age-dependent decline in HSR. Finally, we tested the effect of Sir2 knockdown throughout adult life by using our new RNA interference (RNAi) method by feeding. Sir2 knockdown severely reduced both the median lifespan as well as significantly increased mortality following heat shock. Our study provides the first characterization and functional study of Daphnia Sir2

Telomerase activity in Daphnia.

<p>A) Telomeric repeat amplification protocol (TRAP) assay of <i>D</i>. <i>pulex</i> extracts. The amount of cell extract used is indicated above each lane. HI: Heat Inactivated, CE: Cell Extract. TSR8 CT: positive control for PCR step. B) Quantification of the TRAP Assay in 1A. Student T-test was performed, p values are as follows: * = 6.15x10^-6, ** = 6.63x10^-6 (n = 3).</p

Telomerase from <i>Daphnia</i> embryos shows high processivity.

<p>A) TRAP assay from egg stage 1 embryos and 1 week old adults of <i>D</i>. <i>pulex</i> and <i>D</i>. <i>pulicaria</i>. 250 ng of <i>Daphnia</i> extract was used in each lane. B) Quantification of the TRAP assay displayed in 2 A. C) Quantification of the processivity of telomerase from each displayed sample. The p values calculated from student T-tests are as follows: * = 6.15x10^-6, ** = 5.56x10^-6, *** = 0.0005,**** = 1.5x10^-5; # = 0.0002, ## = 0.0002 (n = 4).</p

Comparison of telomerase activity at different ages in <i>D</i>. <i>pulex</i> and <i>D</i>. <i>pulicaria</i>.

<p>A) TRAP assay was performed using <i>Daphnia</i> extracts prepared at indicated ages. Lanes 1–3: <i>D</i>. <i>pulex</i>, lanes 4–6: <i>D</i>. <i>pulicaria</i>. B) Quantification of the TRAP assay displayed in 4 A. C) Quantification of the processivity of telomerase from each displayed sample. Student T-tests were performed, and p values are as follows * = 0.0005, ** = 0.0006, *** = 0.002, # = 0.001, ## = 0.034, ### = 0.0132, #### = 0.029 (n = 4).</p