We present a photonpair source at 2 µm with more than 45 THz bandwidth and a generation rate of 122 GHz/mW in lithium niobate nanophotonics, opening up many opportunities in midinfrared quantum information processing.
more » « less Award ID(s):
 1846273
 NSFPAR ID:
 10544735
 Publisher / Repository:
 Optica Publishing Group
 Date Published:
 ISBN:
 9781957171258
 Page Range / eLocation ID:
 FF2L.2
 Format(s):
 Medium: X
 Location:
 San Jose, CA
 Sponsoring Org:
 National Science Foundation
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We tested this prediction in crab spiders (
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A brief report on the effects of vasoactive agents on peripheral venous waveforms in a porcine model
Objectives Noninvasive venous waveform analysis (NIVA) is a recently described, novel technique to assess intravascular volume status. Waveforms are captured with a piezoelectric sensor; analysis in the frequency domain allows for calculation of a “NIVA value” that represents volume status. The aim of this report was to determine the effects of vasoactive agents on the venous waveform and calculated NIVA values.
Design Porcine experimental model.
Setting Operating theatre.
Participants A piezoelectric sensor was secured over the surgically exposed saphenous vein in eight anesthetized pigs.
Main outcome measures NIVA value, pulmonary capillary wedge pressure (PCWP), and mean arterial pressure prior to and post intravenous administration of 150–180 µg of phenylephrine or 100 µg of sodium nitroprusside.
Results Phenylephrine led to a decrease in NIVA value (mean 9.2 vs. 4.6, p < 0.05), while sodium nitroprusside led to an increase in NIVA value (mean 9.5 vs. 11.9, p < 0.05). Mean arterial pressure increased after phenylephrine ( p < 0.05) and decreased after sodium nitroprusside ( p < 0.05). PCWP did not change significantly after phenylephrine ( p = 0.25) or sodium nitroprusside ( p = 0.06).
Conclusions Vasoactive agents lead to changes in noninvasively obtained venous waveforms in euvolemic pigs, highlighting a potential limitation in the ability to NIVA to estimate static volume in this setting. Further studies are indicated to understand the effects of vasoactive agents in the setting of hypovolemia and hypervolemia.

Abstract Catalytic enantioselective 1,2dicarbofunctionalization (1,2DCF) of alkenes is a powerful transformation of growing importance in organic synthesis for constructing chiral building blocks, bioactive molecules, and agrochemicals. Both in a two and threecomponent context, this family of reactions generates densely functionalized, structurally complex products in a single step. Across several distinct mechanistic pathways at play in these transformations with nickel or palladium catalysts, stereocontrol can be obtained through tailored chiral ligands. In this Review we discuss the various strategies, mechanisms, and catalysts that have been applied to achieve enantioinduction in alkene 1,2DCF.
1 Introduction
2 TwoComponent Enantioselective 1,2DCF via Migratory Insertion
3 TwoComponent Enantioselective 1,2DCF via Radical Capture
4 ThreeComponent Enantioselective 1,2DCF via Radical Capture
5 ThreeComponent Enantioselective 1,2DCF via Migratory Insertion
6 Miscellaneous Mechanisms
7 Conclusion