Stem tilting in the inter-tropical cactusEchinocactus platyacanthus: an adaptive solution to the trade-off between radiation acquisition and temperature control

ABSTRACTInsertions and deletions (InDels) are frequently observed in natural protein evolution, yet their potential remains untapped in laboratory evolution. Here we introduce a transposon mutagenesis approach (TRIAD) to generate libraries of random variants with short in-frame InDels, and screen TRIAD libraries to evolve a promiscuous arylesterase activity in a phosphotriesterase. The evolution exhibits features that are distinct from previous point mutagenesis campaigns: while the average activity of TRIAD variants is more deleterious, a larger proportion has successfully adapted for the new activity, exhibiting different functional profiles: (i) both strong and weak trade-off in original vs promiscuous activity are observed; (ii) trade-off is more severe (10- to 20-fold increased kcat/KM in arylesterase with ∼100-fold decreases in the original phosphotriesterase activity) and (iii) improvements show up in kcat rather than KM, suggesting novel adaptive solution. These distinct features make TRIAD an alternative to widely used point mutagenesis, providing access to functional innovations and traversing unexplored fitness landscape regions.

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A High Angle, Double Tilting Cold Stage for the AEI EM7

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052262 ◽

1974 ◽

Vol 32 ◽

pp. 450-451

Author(s):

P.R. Swann ◽

A.E. Lloyd

Keyword(s):

Habit Plane ◽

Temperature Control ◽

Tilt Angle ◽

Cooling System ◽

Thermal Drift ◽

High Angle ◽

Cold Stage ◽

High Degree ◽

Better Than

Figure 1 shows the design of a specimen stage used for the in situ observation of phase transformations in the temperature range between ambient and −160°C. The design has the following features a high degree of specimen stability during tilting linear tilt actuation about two orthogonal axes for accurate control of tilt angle read-out high angle tilt range for stereo work and habit plane determination simple, robust construction temperature control of better than ±0.5°C minimum thermal drift and transmission of vibration from the cooling system.

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A Flow-Preserving Algorithm for the Time-Cost Trade-Off Problem

IIE Transactions ◽

10.1080/05695558208974589 ◽

1982 ◽

Vol 14 (2) ◽

pp. 109-113 ◽

Cited By ~ 4

Author(s):

Suleyman Tufekci

Keyword(s):

Time Cost ◽

Trade Off

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Review for "Dynamic and precise temperature control unit for PEMFC single‐cell testing"

10.1002/eng2.12345/v1/review1 ◽

2020 ◽

Keyword(s):

Single Cell ◽

Temperature Control ◽

Control Unit ◽

Temperature Control Unit ◽

Cell Testing

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Dual Goals for Speed and Accuracy on the Same Performance Task

Journal of Personnel Psychology ◽

10.1027/1866-5888/a000063 ◽

2012 ◽

Vol 11 (3) ◽

pp. 118-126 ◽

Cited By ~ 3

Author(s):

Olive Emil Wetter ◽

Jürgen Wegge ◽

Klaus Jonas ◽

Klaus-Helmut Schmidt

Keyword(s):

Memory Scanning ◽

Performance Task ◽

Performance Tasks ◽

Trade Off ◽

Test Experiment ◽

Trade Offs ◽

New Finding ◽

Sternberg Paradigm ◽

Speed Accuracy ◽

Speed And Accuracy

In most work contexts, several performance goals coexist, and conflicts between them and trade-offs can occur. Our paper is the first to contrast a dual goal for speed and accuracy with a single goal for speed on the same task. The Sternberg paradigm (Experiment 1, n = 57) and the d2 test (Experiment 2, n = 19) were used as performance tasks. Speed measures and errors revealed in both experiments that dual as well as single goals increase performance by enhancing memory scanning. However, the single speed goal triggered a speed-accuracy trade-off, favoring speed over accuracy, whereas this was not the case with the dual goal. In difficult trials, dual goals slowed down scanning processes again so that errors could be prevented. This new finding is particularly relevant for security domains, where both aspects have to be managed simultaneously.

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