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David G Welkie

from Carlsbad, CA
Age ~38
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Related to:
Alonso I Zuniga, 71Gonzala Perez, 72Maria Socorro Perez, 61
Connected to:
Regina Welkie, 44Krista A Welko, 54James T Welkos, 60Arthur Welkowitz, 88Chris W Welky, 68Linda J Welky, 70Audrey L Well, 83Betsy L Well, 43Billy J Well, 89Doris E Well, 97

David Welkie Phones & Addresses

  • Carlsbad, CA
  • Lafayette, IN
  • Trumbull, CT
  • Madison, WI

Work

Company: University of california, san diego Sep 2015 to Nov 2019 Position: Postdoctoral research scholar, center for circadian biology

Education

School / High School: Uc San Diego Extension 2018 to 2018 Specialities: Leadership, Project Management

Skills

Microbiology • Molecular Biology • Molecular Cloning • Pcr • Cell Culture • Research • Statistics • Laboratory • Microscopy • Fluorescence Microscopy • Teaching • Flow Cytometry • Protein Purification • Western Blotting • Protein Expression • Gas Chromatography • Spectrophotometry • Cell Sorting • Rna Isolation • Mentoring • Polymerase Chain Reaction • Laboratory Skills • R • R Programming

Languages

English

Ranks

Certificate: Introduction To Genomic Technologies

Industries

Biotechnology

Resumes

Resumes

David Welkie Photo 1

Scientist I

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Location:
San Diego, CA
Industry:
Biotechnology
Work:
University of California, San Diego Sep 2015 - Nov 2019
Postdoctoral Research Scholar, Center For Circadian Biology
Synthorx Inc Sep 2015 - Nov 2019
Scientist I
Purdue University Aug 2009 - May 2015
Doctoral Research Scientist, Department of Biological Sciences
University of Wisconsin-Madison 2008 - 2009
Undergraduate Research Fellow
Education:
Uc San Diego Extension 2018 - 2018
University of California, San Diego - Rady School of Management 2017 - 2017
Master of Business Administration, Masters, Business Administration, Management, Business Administration and Management Purdue University 2009 - 2015
Doctorates, Doctor of Philosophy, Philosophy University of Wisconsin - Madison 2005 - 2009
Bachelors, Bachelor of Science, Microbiology
Skills:
Microbiology
Molecular Biology
Molecular Cloning
Pcr
Cell Culture
Research
Statistics
Laboratory
Microscopy
Fluorescence Microscopy
Teaching
Flow Cytometry
Protein Purification
Western Blotting
Protein Expression
Gas Chromatography
Spectrophotometry
Cell Sorting
Rna Isolation
Mentoring
Polymerase Chain Reaction
Laboratory Skills
R
R Programming
Languages:
English
Certifications:
Introduction To Genomic Technologies
The Data Scientist’s Toolbox
R Programming
Introduction To R
Intermediate R

Publications

Us Patents

Charged Particle Trapping In Near-Surface Potential Wells

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US Patent:
6683301, Jan 27, 2004
Filed:
Jan 25, 2002
Appl. No.:
10/056671
Inventors:
Craig Whitehouse - Branford CT
David G. Welkie - Branford CT
Assignee:
Analytica of Branford, Inc. - Branford CT
International Classification:
H01J 4916
US Classification:
250288, 250287
Abstract:
A Time-Of-Flight mass spectrometer is configured with a pulsing region and electronic controls that generate a potential well for ions in the pulsing region, due to the repelling effect of a high-frequency electric field that is created in the space immediately proximate to a surface, and an additional static electric field that accelerates ions toward the surface. Ions can be constrained and accumulated over time in the potential well prior to acceleration into the Time-Of-Flight tube for mass analysis. Ions can also be directed to collide with the surface with high energy to cause Surface Induced Dissociation (SID) fragmentation, or with low energy to effect collisional cooling, hence, better spatial focusing, prior to mass analysis. The apparatus and methods described in the invention result in refined control of ion fragmentation energy and improved Time-Of-Flight mass analysis performance.

Charged Particle Trapping In Near-Surface Potential Wells

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US Patent:
6872941, Mar 29, 2005
Filed:
Nov 20, 2003
Appl. No.:
10/719330
Inventors:
Craig M. Whitehouse - Branford CT, US
David G. Welkie - Branford CT, US
Assignee:
Analytica of Branford, Inc. - Branford CT
International Classification:
H01J049/16
US Classification:
250288, 250287
Abstract:
A Time-Of-Flight mass spectrometer is configured with a pulsing region and electronic controls that generate a potential well for ions in the pulsing region, due to the repelling effect of a high-frequency electric field that is created in the space immediately proximate to a surface, and an additional static electric field that accelerates ions toward the surface. Ions can be constrained and accumulated over time in the potential well prior to acceleration into the Time-Of-Flight tube for mass analysis. Ions can also be directed to collide with the surface with high energy to cause Surface Induced Dissociation (SID) fragmentation, or with low energy to effect collisional cooling, hence, better spatial focusing, prior to mass analysis. The apparatus and method described in the invention result in refined control of ion fragmentation energy and improved Time-Of-Flight mass analysis performance.

Fragmentation Methods For Mass Spectrometry

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US Patent:
6919562, Jul 19, 2005
Filed:
May 30, 2003
Appl. No.:
10/448477
Inventors:
Craig M. Whitehouse - Branford CT, US
David G. Welkie - Branford CT, US
Gholamreza Javahery - Branford CT, US
Lisa Cousins - Branford CT, US
Sergey Rakov - Branford CT, US
Assignee:
Analytica of Branford, Inc. - Branford CT
International Classification:
H01J049/26
US Classification:
250288
Abstract:
Apparatus and methods are provided that enable the interaction of low-energy electrons and positrons with sample ions to facilitate electron capture dissociation (ECD) and positron capture dissociation (PCD), respectively, within multipole ion guide structures. It has recently been discovered that fragmentation of protonated ions of many biomolecules via ECD often proceeds along fragmentation pathways not accessed by other dissociation methods, leading to molecular structure information not otherwise easily obtainable. However, such analyses have been limited to expensive Fourier transform ion cyclotron resonance (FTICR) mass spectrometers; the implementation of ECD within commonly-used multipole ion guide structures is problematic due to the disturbing effects of RF fields within such devices. The apparatus and methods described herein successfully overcome such difficulties, and allow ECD (and PCD) to be performed within multipole ion guides, either alone, or in combination with conventional ion fragmentation methods. Therefore, improved analytical performance and functionality of mass spectrometers that utilize multipole ion guides are provided.

Mass Spectrometry With Segmented Rf Multiple Ion Guides In Various Pressure Regions

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US Patent:
7034292, Apr 25, 2006
Filed:
May 30, 2003
Appl. No.:
10/448495
Inventors:
Craig M. Whitehouse - Branford CT, US
David G. Welkie - Branford CT, US
Gholamreza Javahery - Branford CT, US
Lisa Cousins - Branford CT, US
Assignee:
Analytica of Branford, Inc. - Branford CT
International Classification:
H01J 49/00
B01D 59/44
US Classification:
250289, 250281
Abstract:
A mass spectrometer is configured with individual multipole ion guides, configured in an assembly in alignment along a common centerline wherein at least a portion of at least one multipole ion guide mounted in the assembly resides in a vacuum region with higher background pressure, and the other portion resides in a vacuum region with lower background pressure. Said multipole ion guides are operated in mass to charge selection and ion fragmentation modes, in either a high or low pressure region, said region being selected according to the optimum pressure or pressure gradient for the function performed. The diameter, lengths and applied frequencies and phases on these contiguous ion guides may be the same or may differ. A variety of MS and MS/MSanalysis functions can be achieved using a series of contiguous multipole ion guides operating in either higher background vacuum pressures, or along pressure gradients in the region where the pressure drops from high to low pressure, or in low pressure regions. Individual sets of RF, +/−DC and resonant frequency waveform voltage supplies provide potentials to the rods of each multipole ion guide allowing the operation of ion transmission, ion trapping, mass to charge selection and ion fragmentation functions independently in each ion guide.

Apparatus And Methods For Reduction Of Coherent Noise In A Digital Signal Averager

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US Patent:
7043406, May 9, 2006
Filed:
Apr 23, 2003
Appl. No.:
10/421590
Inventors:
David G. Welkie - Branford CT, US
Craig M. Whitehouse - Branford CT, US
Assignee:
Analytica of Branford, Inc. - Branford CT
International Classification:
H04B 15/00
US Classification:
702194, 25030808, 25030809
Abstract:
Apparatus and methods are provided for reducing coherent noise in measurements of repetitive analog signal waveforms by digital signal averagers. Coherent noise is repetitive and synchronous with the signal waveform and is therefore undiminished by conventional signal averaging techniques. A major source of coherent noise is the repetitive voltage transitions that occur within the digital signal averager itself. The apparatus and methods of the present invention introduce a known and variable phase offset during the signal averaging process between the signal waveform being measured and the internally generated coherent noise, thereby allowing such coherent noise to be averaged, and therefore reduced, during the signal averaging process. Consequently, the apparatus and methods of the present invention allow greater signal-to-noise ratio and signal dynamic range than with the prior art.

Fragmentation Methods For Mass Spectrometry

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US Patent:
7049584, May 23, 2006
Filed:
Jul 19, 2005
Appl. No.:
11/184387
Inventors:
Craig M. Whitehouse - Branford CT, US
David G. Welkie - Branford CT, US
Gholamreza Javahery - Branford CT, US
Lisa Cousins - Branford CT, US
Sergey Rakov - Branford CT, US
Assignee:
Analytica of Branford, Inc. - Branford CT
International Classification:
H01J 49/26
US Classification:
250288
Abstract:
Apparatus and methods are provided that enable the interaction of low-energy electrons and positrons with sample ions to facilitate electron capture dissociation (ECD) and positron capture dissociation (PCD), respectively, within multipole ion guide structures. It has recently been discovered that fragmentation of protonated ions of many biomolecules via ECD often proceeds along fragmentation pathways not accessed by other dissociation methods, leading to molecular structure information not otherwise easily obtainable. However, such analyses have been limited to expensive Fourier transform ion cyclotron resonance (FTICR) mass spectrometers; the implementation of ECD within commonly-used multipole ion guide structures is problematic due to the disturbing effects of RF fields within such devices. The apparatus and methods described herein successfully overcome such difficulties, and allow ECD (and PCD) to be performed within multipole ion guides, either alone, or in combination with conventional ion fragmentation methods. Therefore, improved analytical performance and functionality of mass spectrometers that utilize multipole ion guides are provided.

Multiple Detection Systems

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US Patent:
7265346, Sep 4, 2007
Filed:
May 24, 2002
Appl. No.:
10/155191
Inventors:
Craig M. Whitehouse - Branford CT, US
David G. Welkie - Branford CT, US
Assignee:
Analytica of Brandford, Inc. - Branford CT
International Classification:
H01J 49/40
US Classification:
250287, 250281, 250305, 250394
Abstract:
A particle detection system is configured and operated as two or more separate and completely independent detection systems. The detection systems may be of the same or different design, may be operated in the same or different modes, and may be operated with the same or different operating parameters. Each detection system may record signals simultaneously, or alternately; the measurements obtained from each of the detection systems may either be combined into a single unified data set, or recorded separately. Means are provided to direct particles to impinge on one of the detectors or any of the other detectors. Alternatively, a population of particles can be dispersed in a manner that allows a population of particles to be distributed among two or more detectors simultaneously. The implementation of completely independent detection systems, for example, in a Time-of-Flight mass spectrometer, allows the design and operation of each detection system to be optimized independently, while being employed simultaneously. The flexibility afforded by the apparatus and methods in the invention allows signals to be recorded with enhanced signal dynamic range, signal-to-noise, and/or temporal resolution, relative to other presently available detection systems.

Apparatus And Methods For Reduction Of Coherent Noise In A Digital Signal Averager

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US Patent:
7321847, Jan 22, 2008
Filed:
May 5, 2006
Appl. No.:
11/429094
Inventors:
David G. Welkie - Branford CT, US
Craig M. Whitehouse - Branford CT, US
Assignee:
Analytica of Branford, Inc. - Branford CT
International Classification:
G06F 15/00
G06F 7/38
US Classification:
702199, 702189, 708445
Abstract:
Apparatus and methods are provided for reducing coherent noise in measurements of repetitive analog signal waveforms by digital signal averagers. Coherent noise is repetitive and synchronous with the signal waveform and is therefore undiminished by conventional signal averaging techniques. A major source of coherent noise is the repetitive voltage transitions that occur within the digital signal averager itself. The apparatus and methods of the present invention introduce a known and variable phase offset during the signal averaging process between the signal waveform being measured and the internally generated coherent noise, thereby allowing such coherent noise to be averaged, and therefore reduced, during the signal averaging process. Consequently, the apparatus and methods of the present invention allow greater signal-to-noise ratio and signal dynamic range than with the prior art.
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David G Welkie from Carlsbad, CA, age ~38 Get Report